0001558370-25-001773 | 10-K | XBRL Viewer | Ribbon Communications INC

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ACCOUNTS RECEIVABLE, NET (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
ACCOUNTS RECEIVABLE, NET
Accounts receivable	$ 256,174	$ 269,933
Allowance for doubtful accounts	(1,456)	(1,512)	$ (1,427)	$ (1,270)
Accounts receivable, net	$ 254,718	$ 268,421

ACCRUED EXPENSES AND OTHER (Tables)

12 Months Ended

Dec. 31, 2024

ACCRUED EXPENSES AND OTHER

Schedule of accrued expenses

Accrued expenses and other consisted of the following (in thousands):


	December 31,		December 31,
	2024		2023
Employee compensation and related costs	$	44,948	$	33,682
Professional fees		16,339		19,702
Taxes payable		6,364		8,383
Other		38,600		29,920
	$	106,251	$	91,687

INTANGIBLE ASSETS AND GOODWILL (Tables)

12 Months Ended

Dec. 31, 2024

INTANGIBLE ASSETS AND GOODWILL

Schedule of intangible assets

The Company’s intangible assets at December 31, 2024 and 2023 consisted of the following (in thousands):


	Weighted
	average
	amortization					Net
	period			Accumulated		carrying
December 31, 2024	(years)	Cost		amortization		value
Developed technology	7.84	$	340,380	$	262,085	$	78,295
Customer relationships	11.86		268,140		160,635		107,505
Trade names	3.88		5,000		4,978		22
Software licenses	3.00		5,748		4,033		1,715
	9.50	$	619,268	$	431,731	$	187,537


	Weighted
	average
	amortization					Net
	period			Accumulated		carrying
December 31, 2023	(years)	Cost		amortization		value
Developed technology	7.84	$	340,380	$	239,066	$	101,314
Customer relationships	11.86		268,140		134,743		133,397
Trade names	3.88		5,000		4,901		99
Software licenses	3.00		5,436		2,159		3,277
	9.51	$	618,956	$	380,869	$	238,087

Schedule of estimated future amortization expense for intangible assets

Estimated future amortization expense for the Company’s intangible assets at December 31, 2024 was as follows (in thousands):


Years ending December 31,
2025	$	44,192
2026		39,143
2027		33,979
2028		23,400
2029		18,379
Thereafter		28,444
	$	187,537

Schedule of goodwill

The components of goodwill at December 31, 2024 and 2023 were as follows (in thousands):


	Cloud and		IP Optical
	Edge		Networks		Total
Goodwill	$	392,302	$	191,996	$	584,298
Accumulated impairment losses		(167,406)		(116,000)		(283,406)
	$	224,896	$	75,996	$	300,892

- Definition

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
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-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-2

+ Details

EARNINGS (LOSS) PER SHARE

12 Months Ended

Dec. 31, 2024

EARNINGS (LOSS) PER SHARE

EARNINGS (LOSS) PER SHARE

(5) EARNINGS (LOSS) PER SHARE

Basic earnings (loss) per share is computed by dividing net income (loss) by the weighted average number of shares outstanding during the period. For periods in which the Company reports net income, diluted net earnings per share is determined by using the weighted average number of common and dilutive common equivalent shares outstanding during the period, unless the effect is antidilutive.

The shares used to compute loss per share were as follows (in thousands):


	Year ended December 31,
	2024	2023	2022
Weighted average shares outstanding—basic	174,044	170,408	156,668
Potential dilutive common shares	—	—	—
Weighted average shares outstanding—diluted	174,044	170,408	156,668

Options to purchase the Company’s common stock and unvested restricted and performance-based stock units aggregating 7.6 million shares, 13.5 million shares, and 14.5 million shares were excluded from the computation of diluted loss per share for the years ended December 31, 2024, 2023 and 2022, respectively, because their effect would have been antidilutive.

As of December 31, 2024 and 2023, the potential number of dilutive shares from the Warrants totaled 4.9 million shares. However, there was no impact on weighted average shares outstanding from these Warrants for the years ended December 31, 2024 and 2023 as the average share price of the Company’s common stock was below the exercise price of $3.77 per share and their effect would have been antidilutive.

Dividends accrued on the Preferred Stock were not an adjustment to net income (loss) used for the calculation of diluted earnings (loss) per share as these dividends are included in the fair value adjustment of the Preferred Stock which was reflected in Other expense, net until the redemption of the Preferred Stock on June 25, 2024.

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Consolidated Balance Sheets
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	55,000
Preferred stock, shares outstanding (in shares)	0	55,000
Preferred stock, liquidation preference, value		$ 56,650
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	240,000,000	240,000,000
Common stock, shares issued (in shares)	175,599,250	172,083,667
Common stock, shares outstanding (in shares)	175,599,250	172,083,667

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net loss	$ (54,235)	$ (66,206)	$ (98,083)
Adjustments to reconcile net loss to cash flows provided by (used in) operating activities:
Depreciation and amortization of property and equipment	13,539	14,105	15,295
Amortization of intangible assets	50,862	56,891	61,188
Amortization of debt issuance costs and original issue discount	4,847	3,241	2,308
Amortization of accumulated other comprehensive gain related to interest rate swap	(8,196)	(5,575)
Stock-based compensation	16,086	21,806	18,707
Deferred income taxes	(16,887)	(9,196)	(18,251)
Gain on sale of business			(62)
Decrease in fair value of investments			41,291
Gain on sale of swap		(7,301)
Change in fair value of warrant liability	2,769	(201)
Change in fair value of preferred stock liability	8,091	1,548
Dividends accrued on preferred stock liability	2,743	3,935
Payment of dividends accrued on preferred stock liability	(6,686)
Foreign currency exchange losses (gains)	5,741	(44)	1,576
Changes in operating assets and liabilities:
Accounts receivable	12,420	5,726	14,285
Inventory	(3,616)	(10,701)	(32,099)
Other operating assets	30,459	34,834	2,109
Accounts payable	(6,016)	(10,498)	(448)
Accrued expenses and other long-term liabilities	(9,367)	(14,684)	(37,635)
Deferred revenue	7,686	(593)	3,455
Net cash provided by (used in) operating activities	50,240	17,087	(26,364)
Cash flows from investing activities:
Purchases of property and equipment	(22,406)	(9,381)	(10,254)
Purchases of software licenses	(462)	(100)	(3,300)
Proceeds from sale of business			1,418
Net cash used in investing activities	(22,868)	(9,481)	(12,136)
Cash flows from financing activities:
Borrowings under revolving line of credit	44,106	97,000	73,625
Principal payments on revolving line of credit	(44,106)	(97,000)	(73,625)
Proceeds from issuance of term debt	342,300
Principal payments of term debt	(237,145)	(95,058)	(45,058)
Principal payments of finance leases			(595)
Payment of debt issuance costs	(6,312)	(1,685)	(1,046)
Proceeds from equity offering			52,067
Payment of equity offering issuance costs			(1,654)
Proceeds from issuance of preferred stock and warrant liabilities		53,350
Payment of preferred stock liability	(56,850)
Proceeds from the exercise of stock options	21	15	1
Payment of tax obligations related to vested stock awards and units	(4,308)	(4,481)	(2,784)
Net cash provided by (used in) financing activities	37,706	(47,859)	931
Effect of exchange rate changes on cash and cash equivalents	(1,229)	(379)	(1,654)
Net increase (decrease) in cash and cash equivalents	63,849	(40,632)	(39,223)
Cash, cash equivalents and restricted cash, beginning of year	26,630	67,262	106,485
Cash, cash equivalents and restricted cash, end of year	90,479	26,630	67,262
Supplemental disclosure of cash flow information:
Interest paid	32,969	25,573	19,336
Income taxes paid	29,280	18,876	16,988
Income tax refunds received	1,545	1,611	1,251
Supplemental disclosure of non-cash investing activities:
Capital expenditures incurred, but not yet paid	10,090	2,578	2,559
Inventory transfers to property and equipment	2,165	1,693	2,896
Software license acquired through investment disposal			1,886
Supplemental disclosure of non-cash financing activities:
Fair value of vested restricted and performance-based stock grants	$ 14,822	$ 15,571	$ 9,858

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS

12 Months Ended

Dec. 31, 2024

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS

(23) NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS

The Company has defined benefit retirement plans that cover certain employees at various international locations. The Company’s policy is to contribute amounts at least sufficient to satisfy the minimum amount required by applicable law and regulations or to directly pay benefits where appropriate. Benefits under the defined benefit plans are typically based either on years of service and the employee’s compensation (generally during a fixed number of years immediately before retirement) or on annual credits. The range of assumptions that are used for these non-U.S. defined benefit plans reflect the different economic environments within the various countries.

A reconciliation of the changes in the benefit obligations and fair value of the assets of the defined benefit plans for the years ended December 31, 2024 and 2023, the funded status of the plans, and the amounts recognized in the consolidated balance sheets as of December 31, 2024 and 2023 were as follows (in thousands):


	Year ended December 31,
	2024		2023
Changes in projected benefit obligations:
Projected benefit obligation, beginning of year	$	20,769	$	21,257
Service cost		1,325		1,193
Interest cost		926		938
Participant contributions		—		—
Net actuarial loss (gain) on obligation		343		(402)
Settlement		(945)		(1,773)
Benefits paid		(281)		(444)
Projected benefit obligation, end of year	$	22,137	$	20,769

Changes in plan assets:
Fair value of plan assets, beginning of year	$	13,609	$	14,629
Actual return on plan assets		1,367		183
Employer contributions		707		975
Participant contributions		29		39
Benefits paid		(1,226)		(2,217)
Fair value of plan assets, end of year	$	14,486	$	13,609

Funded status at end of year	$	(7,651)	$	(7,160)

Amounts recognized in accumulated other comprehensive income consist of:
Prior service (credit) cost	$	(2,841)	$	(3,161)
Net actuarial (gain) loss		(1,148)		(1,100)
	$	(3,989)	$	(4,261)

Amounts recognized in the consolidated balance sheets consist of:
Other assets (non-current pension asset)	$	1,567	$	1,013
Accrued expenses and other (current pension liability)		(848)		(764)
Other long-term liabilities (non-current pension liability)		(8,370)		(7,409)
Net amount recognized	$	(7,651)	$	(7,160)

The increase in the underfunded status of the Company’s defined benefit plans at December 31, 2024 compared to December 31, 2023 was primarily due to normal benefit accruals combined with significant lump sum payments in Israel of $0.9 million.

Plans with underfunded or non-funded accumulated benefit obligations at December 31, 2024 and 2023 were as follows (in thousands):


	December 31,
	2024		2023
Aggregate projected benefit obligation	$	11,997	$	10,811
Aggregate accumulated benefit obligation	$	9,586	$	8,547
Aggregate fair value of plan assets	$	2,779	$	2,638

Plans with overfunded accumulated benefit obligations at December 31, 2024 and 2023 were as follows (in thousands):


	December 31,
	2024		2023
Aggregate projected benefit obligation	$	10,140	$	9,958
Aggregate accumulated benefit obligation	$	8,160	$	7,958
Aggregate fair value of plan assets	$	11,707	$	10,971

Net periodic benefit costs for the years ended December 31, 2024, 2023 and 2022 were as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Service cost	$	1,325	$	1,193	$	1,355
Interest cost		926		938		563
Expected return on plan assets		(592)		(607)		(266)
Settlement (credit) charge		(234)		(417)		808
Amortization of prior service cost		(320)		(320)		(320)
Amortization of net (gain) loss		(150)		(165)		275
Net periodic benefit costs	$	955	$	622	$	2,415

Expected benefit payments for the next ten years are as follows (in thousands):


Years ending December 31,
2025	$	1,347
2026		1,301
2027		1,825
2028		2,482
2029		2,369
2030 to 2034		10,998
	$	20,322

The changes in plan assets and benefit obligations recognized in other comprehensive income (loss) before tax for the years ended December 31, 2024, 2023 and 2022 were as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Net (gain) loss	$	(432)	$	22	$	(4,666)
Amortization of net gain (loss)		150		165		(275)
Amortization of prior service credit (cost)		320		320		320
Settlement credit (charge)		234		417		(808)
Total recognized in other comprehensive income (loss)	$	272	$	924	$	(5,429)

The Company defers all actuarial gains and losses resulting from variances between actual results and economic estimates or actuarial assumptions. The unrecognized actuarial gains and losses are recorded as unrealized pension actuarial gains (losses) in the Company’s consolidated balance sheets as a component of Accumulated other comprehensive income. These unrecognized gains and losses are amortized as a component of net periodic benefit cost when the net gains and losses exceed 10% of the greater of the market value of plan assets or the projected benefit obligation at the beginning of the year.

The principal weighted average assumptions used to determine the benefit obligation at December 31, 2024 and 2023 were as follows:


	December 31,
	2024		2023
Discount rate	4.33	%	4.65	%
Rate of compensation increase	4.06	%	3.95	%
Interest crediting rate	1.25	%	1.25	%

The principal weighted average assumptions used to determine net period benefit cost for the years ended December 31, 2024, 2023 and 2022 were as follows:


	Year ended December 31,
	2024		2023		2022
Discount rate	4.65	%	4.74	%	2.24	%
Expected long-term return on plan assets	4.19	%	4.34	%	1.79	%
Rate of compensation increase	4.08	%	4.02	%	3.90	%
Interest crediting rate	1.25	%	1.25	%	1.25	%

Assumed discount rates are used in the measurement of the projected and accumulated benefit obligations, as well as the service and interest cost components of net periodic pension cost. Estimated discount rates reflect the rates at which the pension benefits could be effectively settled. For each defined benefit plan, the Company chooses an estimated discount rate from a readily available market index rate, based upon high-quality fixed income investments, specific to the country or economic zone in which the benefits are paid and taking into account the duration of the plan and the number of participants.

The Company’s plans in both the Netherlands and Switzerland are funded through insurance contracts, which have historically provided guaranteed interest credit. The fair value of these contracts is derived from the insurance companies’ assessment of the minimum value of the benefits provided by the insurance contracts. Due to the plan amendment in 2020 that changed the benefit structure of the Netherlands plan, the Company no longer has any obligation related to this plan beyond the payment of insurance premiums. Therefore, there is no projected benefit obligation and no plan assets in the Netherlands. The methodology used to value the Switzerland plan assets assumes that the value of the plan assets equals the guaranteed insured benefits. For consistency, the same discount rate used in the valuation of the benefit obligations is used to place a value on the plan assets. The assets are assumed to grow each year in line with the discount rate, and therefore, the expected return on the assets is set equal to the discount rate. The fair value of the plan assets in Switzerland was $2.8 million at December 31, 2024 and $2.6 million at December 31, 2023. The Company classifies the fair value of its plan assets as Level 2 in the fair value hierarchy as discussed in Note 6.

During the years ended December 31, 2024 and 2023, employees in Switzerland made contributions aggregating $29,000 and $39,000 each year, respectively. Employee contributions to this plan are based on a fixed 5% of the relevant pensionable earnings. The Company funds this plan by contributing at least the minimum amount required by applicable regulations and as recommended by an independent actuary.

During the years ended December 31, 2024, 2023 and 2022, the Company contributed $0.7 million, $1.0 million and $2.0 million, respectively, in total to its defined benefit plans. The Company expects to contribute $1.5 million in total to its defined benefit plans in 2025.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480794/715-70-50-1

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+ Details

INTANGIBLE ASSETS AND GOODWILL - Schedule of Intangible Assets and Amortization (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
INTANGIBLE ASSETS AND GOODWILL
Weighted average amortization period (years)	9 years 6 months	9 years 6 months 3 days
Cost	$ 619,268	$ 618,956
Accumulated amortization	431,731	380,869
Net carrying value	187,537	$ 238,087
Estimated future amortization expense for intangible assets
2025	44,192
2026	39,143
2027	33,979
2028	23,400
2029	18,379
Thereafter	28,444
Total	$ 187,537
Developed technology
INTANGIBLE ASSETS AND GOODWILL
Weighted average amortization period (years)	7 years 10 months 2 days	7 years 10 months 2 days
Cost	$ 340,380	$ 340,380
Accumulated amortization	262,085	239,066
Net carrying value	$ 78,295	$ 101,314
Customer relationships
INTANGIBLE ASSETS AND GOODWILL
Weighted average amortization period (years)	11 years 10 months 9 days	11 years 10 months 9 days
Cost	$ 268,140	$ 268,140
Accumulated amortization	160,635	134,743
Net carrying value	$ 107,505	$ 133,397
Trade names
INTANGIBLE ASSETS AND GOODWILL
Weighted average amortization period (years)	3 years 10 months 17 days	3 years 10 months 17 days
Cost	$ 5,000	$ 5,000
Accumulated amortization	4,978	4,901
Net carrying value	$ 22	$ 99
Software licenses
INTANGIBLE ASSETS AND GOODWILL
Weighted average amortization period (years)	3 years	3 years
Cost	$ 5,748	$ 5,436
Accumulated amortization	4,033	2,159
Net carrying value	$ 1,715	$ 3,277

INCOME TAXES - Reconciliation of company's unrecognized tax benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
INCOME TAXES
Unrecognized tax benefits at January 1	$ 10,932	$ 12,001	$ 17,813
Increases related to current year tax positions	607		156
Increases related to prior period tax positions	53	52	40
Decreases related to the lapse of the applicable statute of limitations	(1,268)	(821)	(560)
Decreases related to prior period tax positions	(4,458)	(300)	(5,448)
Unrecognized tax benefits at December 31,	$ 5,866	$ 10,932	$ 12,001

WARRANTY

12 Months Ended

Dec. 31, 2024

WARRANTY

WARRANTY

(12) WARRANTY

The changes in the Company’s warranty accrual balance in the years ended December 31, 2024 and 2023 were as follows (in thousands):


	Balance at						Balance at
	beginning						end of
Year ended December 31,	of year		Provision		Settlements		year
2024	$	12,243	$	5,423	$	(5,366)	$	12,300
2023	$	11,857	$	5,875	$	(5,489)	$	12,243

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS - Expected future benefit payments (Details) $ in Thousands	Dec. 31, 2024 USD ($)
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
2025	$ 1,347
2026	1,301
2027	1,825
2028	2,482
2029	2,369
2030 to 2034	10,998
Expected future benefit payments	$ 20,322

LEASES (Tables)

12 Months Ended

Dec. 31, 2024

LEASES

Schedule of right-of-use lease assets and lease liabilities

The Company’s right-of-use lease assets and lease liabilities at December 31, 2024 and 2023 were as follows (in thousands):


		December 31,
	Classification	2024		2023
Assets:
Operating lease assets	Operating lease right-of-use assets	$	34,544	$	39,783

Liabilities:
Current Operating	Operating lease liabilities	$	9,443	$	15,739
Non-Current Operating	Operating lease liabilities, net of current		37,376		38,711
Total Operating lease liabilities		$	46,819	$	54,450

Schedule of components of lease expense

The components of lease expense for the years ended December 31, 2024, 2023 and 2022 were as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Operating lease cost*	$	16,637	$	18,767	$	21,121
Finance lease cost:
Amortization of leased assets		—		—		287
Interest on lease liabilities		—		—		13
Short-term lease cost		13,616		13,978		14,209
Variable lease costs (costs excluded from minimum fixed lease payments)**		3,308		3,364		4,007
Sublease income		(788)		(1,376)		(1,647)
Net lease cost	$	32,773	$	34,733	$	37,990

No accelerated amortization was recorded in the year ended December 31, 2024. Operating lease costs for the years ended December 31, 2023 and 2022 include $1.0 million, and $1.6 million, respectively, of accelerated amortization for certain assets partially or fully vacated with no intent or ability to sublease.

No variable costs were accrued in the years ended December 31, 2024 or 2023.Variable lease costs for the year ended December 31, 2022 included accruals of $1.0 million for all future estimated variable expenses related to certain assets partially or fully vacated with no intent or ability to sublease.

Cash flow information related to the Company’s leases for the years ended December 31, 2024, 2023 and 2022 was as follows (in thousands):


	Year ended December 31,
	2024		2023			2022
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	18,619	$	19,021	$	20,363
Operating cash flows from finance leases	$	—	$	—	$	13
Financing cash flows from finance leases	$	—	$	—	$	595

Other information related to the Company’s leases as of December 31, 2024 and 2023 was as follows (in thousands):


	December 31,		December 31,
	2024		2023
Weighted average remaining lease term (years):
Operating leases	5.35		5.50
Weighted average discount rate:
Operating leases	7.73	%	6.34	%

Schedule of Future Minimum Fixed Operating Lease Payments

Future minimum fixed lease payments under noncancelable leases at December 31, 2024 were as follows (in thousands):


	Operating
	leases
2025	$	12,654
2026		11,549
2027		10,221
2028		7,905
2029		5,620
2030 and beyond		9,037
Total lease payments		56,986
Less: interest		(10,167)
Present value of lease liabilities	$	46,819

MAJOR CUSTOMERS (Details)	12 Months Ended
MAJOR CUSTOMERS (Details)	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Verizon Communications Inc. \| Revenue \| Customer
MAJOR CUSTOMERS
Concentration risk, percentage	14.00%	11.00%	15.00%

INCOME TAXES - Reconciliation of effective income tax rate (Details)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
INCOME TAXES
U.S. statutory income tax rate	21.00%	21.00%	21.00%
State income taxes, net of federal benefit	(0.80%)	(2.10%)	1.80%
Foreign income taxes	2.60%	(9.90%)	(1.40%)
Stock-based compensation	(4.20%)	(5.40%)	(2.40%)
Tax credits	2.20%	7.70%	2.20%
Uncertain tax positions	15.20%	2.00%	1.30%
Valuation allowance	(37.20%)	(27.00%)	(3.80%)
Other permanent adjustments	(14.20%)	(1.30%)	(2.60%)
Permanent foreign exchange adjustments	(3.90%)	(2.30%)	(1.40%)
Other, net	1.50%	(2.30%)	(1.80%)
Effective income tax rate	(17.80%)	(19.60%)	12.90%

DEBT - Letters of Credit and Other Guarantees (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
DEBT
Letters of credit outstanding		$ 7,900
Restricted cash	$ 2,709	136
Letters of Credit \| 2020 Credit Facility
DEBT
Letters of credit outstanding		2,700
Letters of Credit \| 2024 Credit Agreement
DEBT
Letters of credit outstanding	0
Various Uncommitted Facilities
DEBT
Letters of credit outstanding	$ 10,900	$ 5,200

EMPLOYEE DEFINED CONTRIBUTION PLANS

12 Months Ended

Dec. 31, 2024

EMPLOYEE DEFINED CONTRIBUTION PLANS

EMPLOYEE DEFINED CONTRIBUTION PLANS

(22) EMPLOYEE DEFINED CONTRIBUTION PLANS

The Company offers 401(k) savings plans to eligible employees. The Company matches 50% of each employee’s contributions to the 401(k) program up to 4% of the employee’s eligible earnings, for a maximum match of 2% of eligible earnings.

The Company recorded expense related to its employee defined contribution plans aggregating $3.0 million, $3.0 million and $3.3 million in the years ended December 31, 2024, 2023 and 2022, respectively.

COMMITMENTS AND CONTINGENCIES (Details) $ in Millions			84 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) $ in Millions	Oct. 14, 2024 USD ($)	Sep. 19, 2022 subsidiary complaint	Dec. 31, 2023	Dec. 31, 2024 USD ($)	Apr. 24, 2024 USD ($)	Nov. 08, 2018 item	Dec. 31, 2016
COMMITMENTS AND CONTINGENCIES
Sale of stock grant interest (as a percent)							100.00%
Unpaid loyalties accrued				$ 1.5
Maximum future royalty commitment				14.0
Maximum future royalty commitment, interest				$ 0.8
Litigation liability amount					$ 4.5
Miller Complaint
COMMITMENTS AND CONTINGENCIES
Number of former officers \| item						3
Charter Complaints
COMMITMENTS AND CONTINGENCIES
Loss contingency, claims filed, number \| complaint		2
Loss contingency, number of defendants \| subsidiary		2
Charter Complaint Filed With Supreme Court Of The State Of New York
COMMITMENTS AND CONTINGENCIES
Loss contingency, claims filed, number \| complaint		1
WideOpenWest Complaint.
COMMITMENTS AND CONTINGENCIES
Litigation liability amount	$ 3.0
Total litigation settlement, amount awarded to WOW	5.0
Total litigation settlement, amount paid to WOW	$ 2.0
Litigation settlement, number of quarterly installments	18 months
Minimum
COMMITMENTS AND CONTINGENCIES
Royalties rates							1.30%
Basis spread on variable rate			1.50%
Maximum
COMMITMENTS AND CONTINGENCIES
Royalties rates							5.00%
Basis spread on variable rate			2.75%

RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES - Components of Restructuring Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES
Severance and related costs	$ 4,036	$ 9,875	$ 5,230
Variable and other facilities-related costs	6,124	5,326	3,992
Accelerated amortization of lease assets due to cease-use		1,008	1,611
Restructuring and related expense	$ 10,160	$ 16,209	$ 10,833

LEASES - Narrative (Details) - USD ($)	12 Months Ended
LEASES - Narrative (Details) - USD ($)	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
LEASES
Operating lease impairment	$ 0	$ 0
Finance lease impairment	0	0
Additional amortization expense		1,008,000	$ 1,611,000
Variable lease cost accrued	0	0	1,000,000
2022 Restructuring Plan
LEASES
Accrual for future anticipated variable lease costs		468,000	2,054,000
Facility Closing
LEASES
Accrual for future anticipated variable lease costs	1,100,000	1,500,000
Facility Closing \| 2022 Restructuring Plan
LEASES
Additional amortization expense	$ 0	$ 1,000,000	1,600,000
Expense recorded for estimated future variable lease costs			$ 1,000,000

INTANGIBLE ASSETS AND GOODWILL - Narratives (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($) segment	Dec. 31, 2023 USD ($)	Oct. 01, 2024 USD ($)
INTANGIBLE ASSETS AND GOODWILL
Number of reporting units \| segment	2
Number of operating segments \| segment	2
Goodwill	$ 300,892	$ 300,892
Goodwill impairment loss	0	0
Goodwill period change in carrying value	0	$ 0
IP Optical Networks
INTANGIBLE ASSETS AND GOODWILL
Goodwill	$ 75,996		$ 76,000

- Definition

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

WARRANTY (Tables)

12 Months Ended

Dec. 31, 2024

WARRANTY

Schedule of changes in accrual balance

The changes in the Company’s warranty accrual balance in the years ended December 31, 2024 and 2023 were as follows (in thousands):


	Balance at						Balance at
	beginning						end of
Year ended December 31,	of year		Provision		Settlements		year
2024	$	12,243	$	5,423	$	(5,366)	$	12,300
2023	$	11,857	$	5,875	$	(5,489)	$	12,243

INVENTORY (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
INVENTORY
On-hand assemblies and finished goods inventories	$ 95,366	$ 93,077
Deferred cost of goods sold	2,430	3,269
Gross inventory	97,796	96,346
Less noncurrent portion (included in Other assets)	(18,617)	(18,825)
Current portion	$ 79,179	$ 77,521

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Factoring of Accounts Receivable and Associated Fees (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Accounts receivable sold	$ 107,874	$ 106,705
Less factoring fees	(2,228)	(2,736)
Net cash proceeds	$ 105,646	$ 103,969

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS - Changes in benefit obligations and fair value of plan (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Changes in projected benefit obligations:
Projected benefit obligation, beginning of year	$ 20,769,000	$ 21,257,000
Service cost	1,325,000	1,193,000	$ 1,355,000
Interest cost	926,000	938,000	563,000
Net actuarial loss (gain) on obligation	343,000	(402,000)
Settlement	(945,000)	(1,773,000)
Benefits and expenses paid	(281,000)	(444,000)
Projected benefit obligation, end of year	22,137,000	20,769,000	21,257,000
Changes in plan assets:
Fair value of plan assets, beginning of year	13,609,000	14,629,000
Actual return on plan assets	1,367,000	183,000
Employer contributions	707,000	975,000	2,000,000
Participant contributions	29,000	39,000
Benefits paid	(1,226,000)	(2,217,000)
Fair value of plan assets, end of year	14,486,000	13,609,000	$ 14,629,000
Funded status at end of year	(7,651,000)	(7,160,000)
Prior service (credit) cost	(2,841,000)	(3,161,000)
Net actuarial (gain) loss	(1,148,000)	(1,100,000)
Accumulated other comprehensive income	(3,989,000)	(4,261,000)
Amounts recognized in the consolidated balance sheets consist of:
Other assets (non-current pension asset)	1,567,000	1,013,000
Accrued expenses and other (current pension liability)	(848,000)	(764,000)
Other long-term liabilities (non-current pension liability)	(8,370,000)	(7,409,000)
Net amount recognized	$ (7,651,000)	$ (7,160,000)

MAJOR CUSTOMERS (Tables)

12 Months Ended

Dec. 31, 2024

MAJOR CUSTOMERS

Schedule of customer contributing 10% or more of the revenue


	Year ended December 31,
	2024		2023		2022
Verizon Communications Inc.	14	%	11	%	15	%

NATURE OF THE BUSINESS (Details)	Dec. 31, 2024 country
NATURE OF THE BUSINESS
Number of countries (over)	30

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS - Principal weighted average assumptions used to determine the benefit obligation (Details)	Dec. 31, 2024	Dec. 31, 2023
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
Discount rate	4.33%	4.65%
Rate of compensation increase	4.06%	3.95%
Interest crediting rate	1.25%	1.25%

BUSINESS ACQUISITIONS

12 Months Ended

Dec. 31, 2024

BUSINESS ACQUISITIONS

BUSINESS ACQUISITIONS

(3) BUSINESS ACQUISITIONS

On March 3, 2020, Ribbon completed its merger transaction with ECI Telecom Group Ltd (“ECI”) in accordance with the terms of the Agreement and Plan of Merger, dated as of November 14, 2019 (the “ECI Acquisition”). Prior to the ECI Acquisition, ECI was a privately-held global provider of end-to-end packet optical transport and software-defined networking (“SDN”) and network function virtualization solutions for service providers, enterprises and data center operators.

The ECI Acquisition was accounted for as a business combination and the financial results of ECI are included in the Company’s consolidated financial statements. Costs related to the integration of the Company and ECI are included in the Acquisition-, disposal- and integration-related expenses in the table below.

Acquisition-, Disposal- and Integration-Related Expenses

Acquisition-related expenses include those expenses related to acquisitions that would otherwise not have been incurred by the Company, including professional and services fees, such as legal, audit, consulting, paying agent and other fees, and expenses related to cash payments to certain former executives of the acquired businesses in connection with their employment agreements. Disposal-related expenses are professional and services fees related to disposals of subsidiaries or portions of the business. Integration-related expenses represent incremental costs related to combining the Company and its business acquisitions, such as third-party consulting and other third-party services related to merging the previously separate companies’ systems and processes.

The integration-related expenses in the years ended December 31, 2023 and 2022 relate to the ECI Acquisition. The disposal-related expenses in the year ended December 31, 2022 primarily related to costs incurred from the sale of one of our foreign subsidiaries.

The components of Acquisition-, disposal- and integration-related expenses incurred in the years ended December 31, 2024, 2023 and 2022 were as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Professional and services fees (disposal-related)	$	—	$	—	$	414
Integration-related expenses		—		4,476		5,872
	$	—	$	4,476	$	6,286

BUSINESS ACQUISITIONS (Details)	12 Months Ended
BUSINESS ACQUISITIONS (Details)	Dec. 31, 2022 subsidiary
BUSINESS ACQUISITIONS
Number of businesses divested	1

RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES

12 Months Ended

Dec. 31, 2024

RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES

RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES

(13) RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES

The Company recorded restructuring and related expense aggregating $10.2 million, $16.2 million and $10.8 million in the years ended December 31, 2024, 2023 and 2022, respectively. Restructuring and related expense includes restructuring expense (primarily severance and related costs), estimated future variable and other lease costs for vacated properties with no intent or ability of sublease, and accelerated rent amortization expense.

For restructuring events that involve lease assets and liabilities, the Company applies lease reassessment and modification guidance and evaluates the right-of-use assets for potential impairment. If the Company plans to exit all or distinct portions of a facility and does not have the ability or intent to sublease, the Company will accelerate the amortization of each of those lease components through the vacate date. The accelerated amortization is recorded as a component of Restructuring and related expense in the Company’s consolidated statements of operations. Related variable lease expenses will continue to be expensed as incurred through the vacate date, at which time the Company will reassess the liability balance to ensure it appropriately reflects the remaining liability associated with the premises and record a liability for the estimated future variable lease costs.

Accelerated amortization of lease assets is recognized from the date that the Company commences the plan to fully or partially vacate a facility, for which there is no intent or ability to enter into a sublease, through the final vacate date. Amounts of accelerated rent amortization that are included as a component of restructuring and related expense are not included in the tables below, as the liability for the total lease payments for each respective facility is included as a component of Operating lease liabilities in the Company’s consolidated balance sheets at December 31, 2024 and 2023, both current and noncurrent (see Note 21). The Company may incur additional future expense if it is unable to sublease other locations included in the Facilities Initiative.

The components of restructuring and related expense for the years ended December 31, 2024, 2023 and 2022 were as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Severance and related costs	$	4,036	$	9,875	$	5,230
Variable and other facilities-related costs		6,124		5,326		3,992
Accelerated amortization of lease assets due to cease-use		—		1,008		1,611
	$	10,160	$	16,209	$	10,833

The Company’s President and CEO approved workforce reductions in 2024 for certain of the Company’s operating locations to correspond with the current sales levels in those areas. The Company recorded $2.1 million in the year ended December 31, 2024 related to these actions.

2023 Restructuring Plan

On February 22, 2023, the Company’s Board of Directors approved a strategic restructuring program (the “2023 Restructuring Plan”) to streamline the Company’s operations in order to support the Company’s investment in critical growth areas. The 2023 Restructuring Plan includes, among other things, charges related to a workforce reduction. Any potential positions eliminated in countries outside the United States are subject to local law and consultation requirements.

In connection with the 2023 Restructuring Plan, the Company recorded restructuring and related expense of $2.0 million and $9.9 million in the years ended December 31, 2024 and 2023, respectively, consisting entirely for severance related costs. A summary of the 2023 Restructuring Plan accrual activity for the years ended December 31, 2024 and 2023 were as follows (in thousands):


	Balance at		Initiatives				Balance at
	January 1,		charged to		Cash		December 31,
	2024		expense		payments		2024
Severance	$	671	$	2,003	$	(2,589)	$	85


	Balance at		Initiatives				Balance at
	January 1,		charged to		Cash		December 31,
	2023		expense		payments		2023
Severance	$	—	$	9,875	$	(9,204)	$	671

The Company estimates that it will record nominal future expense under the 2023 Restructuring Plan.

2022 Restructuring Plan

On February 14, 2022, the Company’s Board of Directors approved a strategic restructuring program (the “2022 Restructuring Plan”) to streamline the Company’s operations in order to support the Company’s investment in critical growth areas. The 2022 Restructuring Plan includes, among other things, charges related to a consolidation of facilities and a workforce reduction. Any positions eliminated in countries outside the United States are subject to local law and consultation requirements.

The Company recorded restructuring and related expense of $6.1 million and $6.3 million in connection with the 2022 Restructuring Initiative in the years ended December 31, 2024 and 2023, respectively. The amount for the year ended December 31, 2023 was comprised of $5.3 million for variable and other facilities-related costs and $1.0 million for accelerated amortization of lease assets no longer being used with no ability or intent to sublease. The Company estimates that it will record approximately $5 million of expense in 2025 under the 2022 Restructuring Plan. A

summary of the 2022 Restructuring Plan accrual activity for the years ended December 31, 2024 and 2023 were as follows (in thousands):


	Balance at		Initiatives				Balance at
	January 1,		charged to		Cash		December 31,
	2024		expense		payments		2024
Variable and other facilities-related costs	$	468	$	6,123	$	(6,244)	$	347


	Balance at		Initiatives				Net transfer to		Balance at
	January 1,		charged to		Cash		operating lease		December 31,
	2023		expense		payments		accounts		2023
Severance	$	1,164	$	—	$	(1,164)	$	—	$	—
Variable and other facilities-related costs		890		5,326		(5,748)		—		468
Accelerated amortization of lease assets due to cease-use		—		1,008		—		(1,008)		—
	$	2,054	$	6,334	$	(6,912)	$	(1,008)	$	468

Balance Sheet Classification

The current portions of accrued restructuring were $1.4 million and $1.1 million at December 31, 2024 and 2023, respectively, and are included as components of Accrued expenses in the consolidated balance sheets. The long-term portions of accrued restructuring are included as components of Other long-term liabilities in the consolidated balance sheets. The long-term portions of accrued restructuring were $0.8 million and $1.1 million at December 31, 2024 and 2023, respectively.

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common stock	Additional paid-in capital	Accumulated deficit	Accumulated other comprehensive (loss) income	Total
Beginning balance (in shares) at Dec. 31, 2021	148,895,308
Beginning balance at Dec. 31, 2021	$ 15	$ 1,875,234	$ (1,355,661)	$ 7,578	$ 527,166
Increase (Decrease) in Stockholders' Equity
Exercise of stock options (in shares)	708
Exercise of stock options		1			1
Vesting of restricted stock awards and units (in shares)	3,075,543
Vesting of performance-based stock units (in shares)	179,184
Shares of restricted stock returned to the Company under net share settlements to satisfy tax withholding obligations (in shares)	(897,059)
Shares of restricted stock returned to the Company under net share settlements to satisfy tax withholding obligations		(2,784)			(2,784)
Common stock issued in equity offering	$ 2	52,065			52,067
Common stock issued in equity offering (in shares)	17,071,311
Issuance costs related to equity offering		(1,654)			(1,654)
Stock-based compensation expense		18,707			18,707
Other comprehensive income (loss)				23,007	23,007
Net loss			(98,083)		(98,083)
Ending balance (in shares) at Dec. 31, 2022	168,324,995
Ending balance at Dec. 31, 2022	$ 17	1,941,569	(1,453,744)	30,585	518,427
Increase (Decrease) in Stockholders' Equity
Exercise of stock options (in shares)	7,816
Exercise of stock options		15			15
Vesting of restricted stock awards and units (in shares)	4,840,738
Vesting of performance-based stock units (in shares)	381,071
Shares of restricted stock returned to the Company under net share settlements to satisfy tax withholding obligations (in shares)	(1,470,953)
Shares of restricted stock returned to the Company under net share settlements to satisfy tax withholding obligations		(4,481)			(4,481)
Stock-based compensation expense		21,806			21,806
Other comprehensive income (loss)				(16,798)	(16,798)
Net loss			(66,206)		$ (66,206)
Ending balance (in shares) at Dec. 31, 2023	172,083,667				172,083,667
Ending balance at Dec. 31, 2023	$ 17	1,958,909	(1,519,950)	13,787	$ 452,763
Increase (Decrease) in Stockholders' Equity
Exercise of stock options (in shares)	11,285
Exercise of stock options		21			21
Vesting of restricted stock awards and units	$ 1				1
Vesting of restricted stock awards and units (in shares)	4,653,037
Vesting of performance-based stock units (in shares)	298,586
Shares of restricted stock returned to the Company under net share settlements to satisfy tax withholding obligations (in shares)	(1,447,325)
Shares of restricted stock returned to the Company under net share settlements to satisfy tax withholding obligations		(4,308)			(4,308)
Stock-based compensation expense		16,086			16,086
Other comprehensive income (loss)				(5,707)	(5,707)
Net loss			(54,235)		$ (54,235)
Ending balance (in shares) at Dec. 31, 2024	175,599,250				175,599,250
Ending balance at Dec. 31, 2024	$ 18	$ 1,970,708	$ (1,574,185)	$ 8,080	$ 404,621

RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES - Restructuring Accrual Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Restructuring plan accrual activity
Initiatives charged to expense	$ 10,160	$ 16,209	$ 10,833
2023 Restructuring Initiative
Restructuring plan accrual activity
Initiatives charged to expense	2,000	9,900
2022 Restructuring Plan
Restructuring plan accrual activity
Balance at the beginning of the period	468	2,054
Initiatives charged to expense	6,100	6,334
Cash payments		(6,912)
Net transfer to operating lease accounts		(1,008)
Balance at the end of the period		468	2,054
Severance \| 2023 Restructuring Initiative
Restructuring plan accrual activity
Balance at the beginning of the period	671
Initiatives charged to expense	2,003	9,875
Cash payments	(2,589)	(9,204)
Balance at the end of the period	85	671
Severance \| 2022 Restructuring Plan
Restructuring plan accrual activity
Balance at the beginning of the period		1,164
Cash payments		(1,164)
Balance at the end of the period			1,164
Variable and other facilities-related costs \| 2022 Restructuring Plan
Restructuring plan accrual activity
Balance at the beginning of the period	468	890
Initiatives charged to expense	6,123	5,326
Cash payments	(6,244)	(5,748)
Balance at the end of the period	347	468	$ 890
Accelerated amortization of lease assets \| 2022 Restructuring Plan
Restructuring plan accrual activity
Initiatives charged to expense	$ 1,000	1,008
Net transfer to operating lease accounts		$ (1,008)

INCOME TAXES - Components of deferred income tax assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Assets:
Net operating loss carryforwards	$ 399,412	$ 398,050
Capital loss carryforwards	100,069	100,061
Tax credit carryforwards	25,405	29,541
Capitalized research and development expenses	71,587	58,959
Deferred revenue	7,687	2,042
Accrued expenses	12,106	10,901
Inventory	1,899	4,108
Stock-based compensation	1,299	1,506
Fixed assets	624	159
Lease liabilities	11,993	12,009
Other temporary differences	1,551	440
Deferred tax assets, gross	633,632	617,776
Valuation allowance	(493,855)	(488,799)
Total deferred tax assets	139,777	128,977
Liabilities:
Intangible assets	(37,488)	(45,448)
Operating lease right-of-use assets	(8,712)	(8,817)
Unremitted foreign income	(10,536)	(10,567)
Total deferred tax liabilities	(56,736)	(64,832)
Deferred income taxes - net noncurrent assets	88,982	69,761
Deferred income taxes - net noncurrent liabilities	(5,941)	(5,616)
Total net deferred tax assets	$ 83,041	$ 64,145

REVENUE RECOGNITION

12 Months Ended

Dec. 31, 2024

REVENUE RECOGNITION

REVENUE RECOGNITION

(17) REVENUE RECOGNITION

The Company’s typical performance obligations include the following:


	When Performance Obligation is Typically
Performance Obligation	Satisfied	When Payment is Typically Due
Software and Product Revenue
Software licenses (perpetual or term)	For perpetual licenses, typically when made available for download (point in time); for term-based licenses, at the beginning of the specified term (point in time)	Generally, within 30-60 days of invoicing, except for term licenses which may be paid for over time
Software licenses (subscription)	Upon activation of hosted site (over time)	Generally, within 30-60 days of invoicing
Hardware	When control of the hardware passes to the customer; typically, upon delivery (point in time)	Generally, within 30-60 days of invoicing
Software upgrades	Upon transfer of control; typically, when made available for download (point in time)	Generally, within 30-60 days of invoicing
Customer Support Revenue
Customer support	Ratably over the course of the support contract (over time)	Generally, within 30-60 days of invoicing
Professional Services
Other professional services (excluding training services)	As work is performed (over time), typically on the input method based on hours incurred	Generally, within 30-60 days of invoicing (upon completion of services)
Training	As the training is delivered (over time), typically one to five days	Generally, within 30-60 days of services being performed

Significant Judgments

The Company’s contracts with customers often include promises to transfer multiple products and services to the customer. Determining whether products and services are considered distinct performance obligations that should be accounted for separately versus together may require significant judgment.

Judgment is required to determine the SSP for each distinct performance obligation. The Company typically has more than one SSP for individual products and services due to the stratification of those products and services by customers and circumstances. In these instances, the Company may use information such as the size of the customer and geographic region in determining the SSP.

Deferred Revenue

Deferred revenue is a contract liability representing amounts collected from or invoiced to customers in excess of revenue recognized. This results primarily from the billing of annual customer support agreements where the revenue is recognized over the term of the agreement. The value of deferred revenue will increase or decrease based on the timing of invoices and recognition of revenue.

Disaggregation of Revenue

The Company disaggregates its revenue from contracts with customers based on the nature of the products and services and the geographic regions in which each customer is domiciled. The Company’s total revenue for the years ended December 31, 2024, 2023 and 2022 was disaggregated geographically as follows:


					Service
			Service		revenue
	Product		revenue		(professional
Year ended December 31, 2024	revenue		(maintenance)		services)		Total revenue
United States	$	201,340	$	133,182	$	61,462	$	395,984
Europe, Middle East and Africa		129,824		71,856		32,999		234,679
Asia Pacific		100,766		39,863		10,941		151,570
Other		15,299		29,681		6,668		51,648
	$	447,229	$	274,582	$	112,070	$	833,881


					Service
			Service		revenue
	Product		revenue		(professional
Year ended December 31, 2023	revenue		(maintenance)		services)		Total revenue
United States	$	161,945	$	133,737	$	48,733	$	344,415
Europe, Middle East and Africa		151,938		75,478		34,485		261,901
Asia Pacific		115,923		39,891		11,269		167,083
Other		15,344		30,546		7,050		52,940
	$	445,150	$	279,652	$	101,537	$	826,339


					Service
			Service		revenue
	Product		revenue		(professional
Year ended December 31, 2022	revenue		(maintenance)		services)		Total revenue
United States	$	175,189	$	132,655	$	44,819	$	352,663
Europe, Middle East and Africa		147,523		75,948		29,310		252,781
Asia Pacific		95,828		41,677		13,594		151,099
Other		24,140		31,815		7,262		63,217
	$	442,680	$	282,095	$	94,985	$	819,760

The Company’s product revenue from its direct sales program and from indirect sales through its channel partner program for the years ended December 31, 2024, 2023 and 2022 was as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Indirect sales through channel partner program	$	170,426	$	157,495	$	131,998
Direct sales		276,803		287,655		310,682
	$	447,229	$	445,150	$	442,680

The Company’s product revenue from sales to enterprise customers and from sales to service provider customers for the years ended December 31, 2024, 2023 and 2022 was as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Sales to enterprise customers	$	176,064	$	143,853	$	125,664
Sales to service provider customers		271,165		301,297		317,016
	$	447,229	$	445,150	$	442,680

The Company’s product revenue and service revenue components by segment for the years ended December 31, 2024, 2023 and 2022 was as follows (in thousands):


	Year ended December 31,
	2024	2023	2022
Product revenue:
Cloud and Edge	211,001	184,730	215,770
IP Optical Networks	236,228	260,420	226,910
Total product revenue	447,229	445,150	442,680

Service revenue:
Maintenance:
Cloud and Edge	212,988	219,939	222,238
IP Optical Networks	61,594	59,713	59,857
Total maintenance revenue	274,582	279,652	282,095
Professional services:
Cloud and Edge	81,168	72,979	70,130
IP Optical Networks	30,902	28,558	24,855
Total professional services revenue	112,070	101,537	94,985
Total service revenue	386,652	381,189	377,080

Revenue Contract Balances

The timing of revenue recognition, billings and cash collections results in billed accounts receivable, unbilled receivables, which are contract assets, and customer advances and deposits, which are contract liabilities, in the Company’s consolidated balance sheets. Amounts are billed as work progresses in accordance with agreed-upon contractual terms, either at periodic intervals or upon achievement of contractual milestones. Billing may occur subsequent to revenue recognition, resulting in contract assets. The Company may receive advances or deposits from its customers before revenue is recognized, resulting in contract liabilities which are classified as deferred revenue. These assets and liabilities are reported in the Company’s consolidated balance sheets on a contract-by-contract basis as of the end of each reporting period. Changes in the contract asset and liability balances during the years ended December 31, 2024 and 2023 were not materially impacted by any factors other than billing and revenue recognition. Nearly all of the Company’s deferred revenue balance is related to services revenue, primarily customer support contracts. Unbilled receivables stem primarily from engagements where services have been performed; however, billing cannot occur until services are completed.

In some arrangements, the Company allows customers to pay for term-based software licenses and products over the term of the software license. The Company also sells SaaS-based software under subscription arrangements, with payment terms over the term of the SaaS agreement. Amounts recognized as revenue in excess of amounts billed are recorded as unbilled receivables. Unbilled receivables that are anticipated to be invoiced in the next twelve months are included in Accounts receivable on the Company’s consolidated balance sheets. The changes in the Company’s accounts receivable, unbilled receivables and deferred revenue balances for the years ended December 31, 2024 and 2023 were as follows (in thousands):


			Unbilled		Deferred		Deferred
	Accounts		accounts		revenue		revenue
	receivable		receivable		(current)		(long-term)
Balance at January 1, 2024	$	186,938	$	81,483	$	113,381	$	19,218
Increase (decrease), net		(10,363)		(3,340)		5,914		1,773
Balance at December 31, 2024	$	176,575	$	78,143	$	119,295	$	20,991


			Unbilled		Deferred		Deferred
	Accounts		accounts		revenue		revenue
	receivable		receivable		(current)		(long-term)
Balance at January 1, 2023	$	170,969	$	96,275	$	113,939	$	19,254
Increase (decrease), net		15,969		(14,792)		(558)		(36)
Balance at December 31, 2023	$	186,938	$	81,483	$	113,381	$	19,218

The Company recognized approximately $110 million of revenue in the year ended December 31, 2024 that was recorded as deferred revenue at December 31, 2023 and approximately $108 million of revenue in the year ended December 31, 2023 that was recorded as deferred revenue at December 31, 2022. Of the Company’s deferred revenue reported as long-term in its consolidated balance sheet at December 31, 2024, the Company expects that approximately $10 million will be recognized as revenue in 2026, approximately $5 million will be recognized as revenue in 2027 and approximately $6 million will be recognized as revenue in 2028 and beyond.

The Company applies the optional exemption of not disclosing the transaction price allocated to the remaining performance obligation for its contracts with an original duration of less than one year. In 2024, the Company entered into a contract with an existing customer that has revenue allocated to remaining performance obligations, which includes unearned revenue and amounts that will be invoiced and recognized as revenue in future periods of $285 million as of December 31, 2024. The Company expects to recognize the remaining revenue over the next three years.

All freight-related customer invoicing is recorded as revenue, while the shipping and handling costs that occur after control of the promised goods or services transfer to the customer are reported as fulfillment costs, a component of Cost of revenue - product in the Company’s consolidated statements of operations.

Deferred Commissions Cost

Sales commissions earned by the Company’s employees are considered incremental and recoverable costs of obtaining a contract with a customer. The payments related to these costs have been deferred on our consolidated balance sheet and are being amortized over the expected life of the customer contract, which is generally five years. At December 31, 2024 and 2023, the Company had $2.8 million and $3.0 million, respectively, of deferred sales commissions capitalized.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-10

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 12
-Subparagraph (a)
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/606/tableOfContent

+ Details

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Consolidated Statements of Comprehensive Loss
Net loss	$ (54,235)	$ (66,206)	$ (98,083)
Other comprehensive (loss) income, net of tax:
Unrealized (loss) gain on interest rate swap, net of reclassifications and amortization into earnings	(6,019)	(10,015)	19,321
Reclassification of gain to other income (expense), net upon sale of interest rate swap		(5,099)
Foreign currency translation adjustments	472	(506)	(792)
Employee retirement benefits	(160)	(1,178)	4,478
Other comprehensive (loss) income, net of tax	(5,707)	(16,798)	23,007
Comprehensive loss, net of tax	$ (59,942)	$ (83,004)	$ (75,076)

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

PROPERTY AND EQUIPMENT

12 Months Ended

Dec. 31, 2024

PROPERTY AND EQUIPMENT

PROPERTY AND EQUIPMENT

(9) PROPERTY AND EQUIPMENT

Property and equipment consisted of the following (in thousands):


		December 31,
	Useful Life	2024		2023
Equipment	2-5 years	$	84,409	$	77,205
Software	2-5 years		36,859		34,802
Furniture and fixtures	3-5 years		3,309		3,301
Leasehold improvements	Shorter of the estimated lease term or useful life		54,849		36,383
			179,426		151,691
Less accumulated depreciation and amortization			(119,062)		(109,871)
Property and equipment, net		$	60,364	$	41,820

As of December 31, 2024 and 2023, property and equipment included $23.2 million and $3.4 million, respectively, of assets that had not yet commenced depreciation. These assets primarily consisted of leasehold improvements and equipment, with the most significant portion related to construction in progress at our new main campus in Petah Tikva, Israel that is expected to be completed and occupied in the 1^st half of 2025, totaling $18.9 million and $0.5 million as of December 31, 2024 and 2023, respectively.

The Company recorded depreciation and amortization expense related to property and equipment of $13.5 million for the year ended December 31, 2024, $14.1 million for the year ended December 31, 2023 and $15.3 million for the year ended December 31, 2022. During each of these years, the Company disposed of certain property and equipment that was fully depreciated at the time of disposal, which resulted in reductions in both Cost and Accumulated depreciation.

The net book values of the Company’s property and equipment by geographic area were as follows (in thousands):


	December 31,
	2024		2023
Israel	$	27,657	$	8,309
United States		20,445		20,807
Asia/Pacific		7,941		8,314
Canada		3,071		3,175
Europe		1,034		957
Other		216		258
	$	60,364	$	41,820

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS (Tables)

12 Months Ended

Dec. 31, 2024

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS

Schedule of changes in projected benefit obligations, fair value of plan assets, and funded status of plan


	Year ended December 31,
	2024		2023
Changes in projected benefit obligations:
Projected benefit obligation, beginning of year	$	20,769	$	21,257
Service cost		1,325		1,193
Interest cost		926		938
Participant contributions		—		—
Net actuarial loss (gain) on obligation		343		(402)
Settlement		(945)		(1,773)
Benefits paid		(281)		(444)
Projected benefit obligation, end of year	$	22,137	$	20,769

Changes in plan assets:
Fair value of plan assets, beginning of year	$	13,609	$	14,629
Actual return on plan assets		1,367		183
Employer contributions		707		975
Participant contributions		29		39
Benefits paid		(1,226)		(2,217)
Fair value of plan assets, end of year	$	14,486	$	13,609

Funded status at end of year	$	(7,651)	$	(7,160)

Amounts recognized in accumulated other comprehensive income consist of:
Prior service (credit) cost	$	(2,841)	$	(3,161)
Net actuarial (gain) loss		(1,148)		(1,100)
	$	(3,989)	$	(4,261)

Amounts recognized in the consolidated balance sheets consist of:
Other assets (non-current pension asset)	$	1,567	$	1,013
Accrued expenses and other (current pension liability)		(848)		(764)
Other long-term liabilities (non-current pension liability)		(8,370)		(7,409)
Net amount recognized	$	(7,651)	$	(7,160)

Schedule of accumulated benefit obligations

Plans with underfunded or non-funded accumulated benefit obligations at December 31, 2024 and 2023 were as follows (in thousands):


	December 31,
	2024		2023
Aggregate projected benefit obligation	$	11,997	$	10,811
Aggregate accumulated benefit obligation	$	9,586	$	8,547
Aggregate fair value of plan assets	$	2,779	$	2,638

Plans with overfunded accumulated benefit obligations at December 31, 2024 and 2023 were as follows (in thousands):


	December 31,
	2024		2023
Aggregate projected benefit obligation	$	10,140	$	9,958
Aggregate accumulated benefit obligation	$	8,160	$	7,958
Aggregate fair value of plan assets	$	11,707	$	10,971

Schedule of net periodic benefit costs

Net periodic benefit costs for the years ended December 31, 2024, 2023 and 2022 were as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Service cost	$	1,325	$	1,193	$	1,355
Interest cost		926		938		563
Expected return on plan assets		(592)		(607)		(266)
Settlement (credit) charge		(234)		(417)		808
Amortization of prior service cost		(320)		(320)		(320)
Amortization of net (gain) loss		(150)		(165)		275
Net periodic benefit costs	$	955	$	622	$	2,415

Schedule of expected benefit payments

Expected benefit payments for the next ten years are as follows (in thousands):


Years ending December 31,
2025	$	1,347
2026		1,301
2027		1,825
2028		2,482
2029		2,369
2030 to 2034		10,998
	$	20,322

Schedule of defined benefit plan amounts recognized in other comprehensive income (loss)

The changes in plan assets and benefit obligations recognized in other comprehensive income (loss) before tax for the years ended December 31, 2024, 2023 and 2022 were as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Net (gain) loss	$	(432)	$	22	$	(4,666)
Amortization of net gain (loss)		150		165		(275)
Amortization of prior service credit (cost)		320		320		320
Settlement credit (charge)		234		417		(808)
Total recognized in other comprehensive income (loss)	$	272	$	924	$	(5,429)

Schedule of assumptions used


	December 31,
	2024		2023
Discount rate	4.33	%	4.65	%
Rate of compensation increase	4.06	%	3.95	%
Interest crediting rate	1.25	%	1.25	%


	Year ended December 31,
	2024		2023		2022
Discount rate	4.65	%	4.74	%	2.24	%
Expected long-term return on plan assets	4.19	%	4.34	%	1.79	%
Rate of compensation increase	4.08	%	4.02	%	3.90	%
Interest crediting rate	1.25	%	1.25	%	1.25	%

BUSINESS ACQUISITIONS - Components of Acquisition, Disposal and Integration-Related Expenses Incurred (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
BUSINESS ACQUISITIONS
Professional and services fees (disposal-related)		$ 414
Integration-related expenses	$ 4,476	5,872
Acquisition- and integration-related	$ 4,476	$ 6,286

INVENTORY (Tables)

12 Months Ended

Dec. 31, 2024

INVENTORY

Schedule of inventory

Inventory consisted of the following (in thousands):


	December 31,		December 31,
	2024		2023
On-hand assemblies and finished goods inventories	$	95,366	$	93,077
Deferred cost of goods sold		2,430		3,269
		97,796		96,346
Less noncurrent portion (included in Other assets)		(18,617)		(18,825)
Current portion	$	79,179	$	77,521

STOCK-BASED COMPENSATION PLANS - Restricted Stock Awards and Units and Performance-Based Stock Units (Details)	12 Months Ended
	Dec. 31, 2024 $ / shares shares
RSUs
Shares
Unvested balance at the beginning of the period (in shares) \| shares	7,091,368
Granted (in shares) \| shares	1,943,760
Vested (in shares) \| shares	(4,653,037)
Forfeited (in shares) \| shares	(384,983)
Unvested balance at the end of the period (in shares) \| shares	3,997,108
Weighted Average Grant Date Fair Value
Unvested balance at the end of the period (in dollars per share) \| $ / shares	$ 3.18
Granted (in dollars per share) \| $ / shares	3.24
Vested (in dollars per share) \| $ / shares	3.33
Forfeited (in dollars per share) \| $ / shares	3.16
Unvested balance at end of the period (in dollars per share) \| $ / shares	$ 3.04
PSUs
Shares
Unvested balance at the beginning of the period (in shares) \| shares	6,297,931
Granted (in shares) \| shares	1,884,337
Vested (in shares) \| shares	(298,586)
Forfeited (in shares) \| shares	(4,277,790)
Unvested balance at the end of the period (in shares) \| shares	3,605,892
Weighted Average Grant Date Fair Value
Unvested balance at the end of the period (in dollars per share) \| $ / shares	$ 2.07
Granted (in dollars per share) \| $ / shares	4.03
Vested (in dollars per share) \| $ / shares	3.12
Forfeited (in dollars per share) \| $ / shares	1.44
Unvested balance at end of the period (in dollars per share) \| $ / shares	$ 3.75

OPERATING SEGMENT INFORMATION (Details) $ in Thousands	12 Months Ended
OPERATING SEGMENT INFORMATION (Details) $ in Thousands	Dec. 31, 2024 USD ($) segment	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
OPERATING SEGMENT INFORMATION
Number of operating segments \| segment	2
Number of reportable segments \| segment	2
Revenue	$ 833,881	$ 826,339	$ 819,760
Gross profit	439,512	408,083	400,936
Research and development	179,941	190,660	203,676
Sales and marketing	137,830	137,460	147,766
General and administrative	68,740	54,962	51,053
Amortization of acquired intangible assets	25,969	28,601	29,646
Acquisition-, disposal- and integration-related		4,476	6,286
Restructuring and related	10,160	16,209	10,833
Interest expense, net	33,821	27,320	19,780
Other expense, net	29,119	3,768	44,495
Loss before income taxes	(46,068)	(55,373)	(112,599)
Segment depreciation expense:
Depreciation expense	13,539	14,105	15,295
Operating segment
OPERATING SEGMENT INFORMATION
Revenue	833,881	826,339	819,760
Cost of revenue	394,369	418,256	418,824
Total segment adjusted gross profit	466,030	439,030	435,106
Reconciling items
OPERATING SEGMENT INFORMATION
Stock-based compensation expense	(1,625)	(2,657)	(2,628)
Amortization of acquired technology	(24,893)	(28,290)	(31,542)
Cloud and Edge
Segment depreciation expense:
Depreciation expense	9,337	9,798	10,758
Cloud and Edge \| Operating segment
OPERATING SEGMENT INFORMATION
Revenue	505,157	477,647	508,137
Cost of revenue	175,940	177,629	197,840
Total segment adjusted gross profit	338,194	314,594	330,395
IP Optical Networks
Segment depreciation expense:
Depreciation expense	4,202	4,307	4,537
IP Optical Networks \| Operating segment
OPERATING SEGMENT INFORMATION
Revenue	328,724	348,692	311,623
Cost of revenue	218,429	240,627	220,984
Total segment adjusted gross profit	$ 127,836	$ 124,436	$ 104,711

EARNINGS (LOSS) PER SHARE - Calculations of Shares Used to Compute Loss Per Share (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Reconciliation of weighted average shares outstanding from basic to diluted
Weighted average shares outstanding-basic	174,044	170,408	156,668
Weighted average shares outstanding-diluted	174,044	170,408	156,668

PROPERTY AND EQUIPMENT (Tables)

12 Months Ended

Dec. 31, 2024

PROPERTY AND EQUIPMENT

Schedule of property and equipment

Property and equipment consisted of the following (in thousands):


		December 31,
	Useful Life	2024		2023
Equipment	2-5 years	$	84,409	$	77,205
Software	2-5 years		36,859		34,802
Furniture and fixtures	3-5 years		3,309		3,301
Leasehold improvements	Shorter of the estimated lease term or useful life		54,849		36,383
			179,426		151,691
Less accumulated depreciation and amortization			(119,062)		(109,871)
Property and equipment, net		$	60,364	$	41,820

The net book values of the Company’s property and equipment by geographic area were as follows (in thousands):


	December 31,
	2024		2023
Israel	$	27,657	$	8,309
United States		20,445		20,807
Asia/Pacific		7,941		8,314
Canada		3,071		3,175
Europe		1,034		957
Other		216		258
	$	60,364	$	41,820

Cover - USD ($)	12 Months Ended
Cover - USD ($)	Dec. 31, 2024	Feb. 24, 2025	Jun. 28, 2024
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2024
Document Transition Report	false
Entity File Number	001-38267
Entity Registrant Name	RIBBON COMMUNICATIONS INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-1669692
Entity Address, Address Line One	6500 Chase Oaks Boulevard, Suite 100
Entity Address, City or Town	Plano
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75023
City Area Code	978
Local Phone Number	614-8100
Title of 12(b) Security	Common Stock, par value $0.0001
Trading Symbol	RBBN
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 240,611,000
Entity Common Stock, Shares Outstanding		175,724,084
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE Portions of the definitive Proxy Statement to be delivered to stockholders in connection with the registrant’s 2025 Annual Meeting of Stockholders are incorporated by reference into Part III of this report.
Entity Central Index Key	0001708055
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	FY
Amendment Flag	false
Auditor Firm ID	34
Auditor Name	Deloitte & Touche LLP
Auditor Location	Dallas, Texas

PREFERRED STOCK AND WARRANTS

12 Months Ended

Dec. 31, 2024

PREFERRED STOCK AND WARRANTS

PREFERRED STOCK AND WARRANTS

(16) PREFERRED STOCK AND WARRANTS

On March 28, 2023, the Company issued 55,000 shares of Preferred Stock to investors in the Private Placement at a price of $970 per share, along with 4,858,090 Warrants with an exercise price of $3.77 per share.

On June 25, 2024, the Company redeemed the Preferred Stock with a portion of the proceeds from the refinancing of the 2020 Credit Facility at a rate of 103% for a total of approximately $63.5 million. The Warrants remain outstanding and without modification. See Note 14 for a description of the refinancing of the 2020 Credit Facility.

The Company accounted for the Preferred Stock until it was redeemed and continues to account for the Warrants as liability-classified instruments based on an assessment of their specific terms in accordance with ASC Topic 480, Distinguishing Liabilities from Equity. The fair value option was elected for the Preferred Stock, as the Company considered fair value to best reflect its expected future economic value. These liabilities are remeasured to fair value at each reporting date using the same valuation methodology applied upon issuance using current input assumptions.

The value of the Preferred Stock was calculated quarterly through March 31, 2024 using the Black-Derman-Toy (BDT) stochastic yield lattice model to capture the optimal timing of repayment, increasing dividend rate and other features and the value of the Warrants is calculated using the Black-Scholes Pricing Model.

Changes in the fair value of the Preferred Stock and Warrants are reported as Other expense, net in the Company’s consolidated statements of operations.

The Company determined the fair value of the Warrants using Level 3 input. The key assumptions input into the models utilized were as follows as of December 31, 2024 and 2023:


	December 31,
	2024			2023
Stock price	$	4.16		$	2.90
Strike price	$	3.77		$	3.77
Risk-free rate		4.21	%		3.95	%
Volatility		57.5	%		60.5	%
Dividend yield		0.0	%		0.0	%
Time to expiration (years)		2.2			3.2
Fair value of Warrant per share	$	1.66		$	1.09

The changes in the Company’s Preferred Stock for the year ended December 31, 2024 and 2023 were as follows (in thousands):


	Year ended December 31,
	2024			2023
Balance at beginning of year	$	53,337	$	—
Issued		—		47,854
Payable in-kind dividends		2,743		3,935
Fair value adjustments		5,605		1,548
Call premium (3%)		1,851		—
Redemption (June 25, 2024)		(63,536)		—
Balance at end of year	$	—	$	53,337

The changes in the Company’s Warrant liabilities for the years ended December 31, 2024 and 2023 were as follows (in thousands):


	Year ended December 31,
	2024		2023
Balance at beginning of year	$	5,295	$	—
Issued		—		5,496
Fair value change		2,769		(201)
Balance at end of year	$	8,064	$	5,295

The Preferred Stock, redeemed on June 25, 2024, was subordinate to the Company’s indebtedness and senior to the Company’s common stock or other equity. Holders of the Preferred Stock were entitled to cumulative dividends that accrued quarterly. Dividends were payable in-kind during the first year at a rate of 9.25%. At the Company’s option, the dividends were payable in-kind or in cash during the second year at a rate of 9.75%. Dividends thereafter were to be payable in cash at a rate of 12.00%. The proceeds from the Preferred Stock issuance were approximately $53.4 million, including $10.0 million from existing related party stockholders. Offering costs paid by the Company of approximately $3.5 million were recorded in Other expense, net in the year ended December 31, 2023. The net proceeds from the Private Placement were used for the repayment of debt. The Preferred Stock was redeemable on or after the first and second anniversaries of the closing date at a rate of 103% and 102%, respectively.

The Warrants are immediately exercisable and upon an event such as a merger, consolidation, asset sale or similar change of control, the Warrants may be exercised and the holders may vote the underlying shares of common stock. In connection with the Private Placement, the Company provided the investors with certain registration rights relating to the Preferred Stock, the Warrants and the shares of the Company’s common stock underlying the Warrants, that required the Company to file a registration statement on Form S-3 with the SEC within 30 days following the closing date of the Private Placement. The registration requirement was completed on May 19, 2023.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478448/946-505-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-16

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

+ Details

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2024

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Schedule of information regarding factoring of accounts receivable and associated fees

Factoring of accounts receivable and associated fees for the years ended December 31, 2024 and 2023 were as follows (in thousands):


	December 31,

	2024		2023
Accounts receivable sold	$	107,874	$	106,705
Less factoring fees		(2,228)		(2,736)
Net cash proceeds	$	105,646	$	103,969

INCOME TAXES (Tables)

12 Months Ended

Dec. 31, 2024

INCOME TAXES

Schedule of income (loss) before taxes

The components of loss from continuing operations before income taxes consisted of the following (in thousands):


	Year ended December 31,
	2024		2023		2022
Income (loss) before income taxes:
United States	$	22,685	$	(5,363)	$	(84,784)
Foreign		(68,753)		(50,010)		(27,815)
	$	(46,068)	$	(55,373)	$	(112,599)

Schedule of income tax expense (benefit)

The provision (benefit) for income taxes from continuing operations consisted of the following (in thousands):


	Year ended December 31,
	2024		2023		2022
Provision (benefit) for income taxes:
Current:
Federal	$	21,619	$	9,927	$	(3,582)
State		3,313		2,790		2,573
Foreign		122		7,312		4,744
Total current		25,054		20,029		3,735
Deferred:
Federal		(13,822)		(10,417)		(10,333)
State		(2,266)		(1,059)		(4,045)
Foreign		(799)		2,280		(3,873)
Total deferred		(16,887)		(9,196)		(18,251)
Total	$	8,167	$	10,833	$	(14,516)

Schedule of effective income tax rate reconciliation


	Year ended December 31,
	2024		2023		2022
U.S. statutory income tax rate	21.0	%	21.0	%	21.0	%
State income taxes, net of federal benefit	(0.8)		(2.1)		1.8
Foreign income taxes	2.6		(9.9)		(1.4)
Stock-based compensation	(4.2)		(5.4)		(2.4)
Tax credits	2.2		7.7		2.2
Uncertain tax positions	15.2		2.0		1.3
Valuation allowance	(37.2)		(27.0)		(3.8)
Other permanent adjustments	(14.2)		(1.3)		(2.6)
Permanent foreign exchange adjustments	(3.9)		(2.3)		(1.4)
Other, net	1.5		(2.3)		(1.8)
Effective income tax rate	(17.8)	%	(19.6)	%	12.9	%

Summary of deferred tax assets and liabilities

The following is a summary of the significant components of deferred income tax assets and liabilities (in thousands):


	December 31,
	2024		2023
Assets:
Net operating loss carryforwards	$	399,412	$	398,050
Capital loss carryforwards		100,069		100,061
Tax credit carryforwards		25,405		29,541
Capitalized research and development expenses		71,587		58,959
Deferred revenue		7,687		2,042
Accrued expenses		12,106		10,901
Inventory		1,899		4,108
Stock-based compensation		1,299		1,506
Fixed assets		624		159
Lease liabilities		11,993		12,009
Other temporary differences		1,551		440
		633,632		617,776
Valuation allowance		(493,855)		(488,799)
Total deferred tax assets		139,777		128,977
Liabilities:
Intangible assets		(37,488)		(45,448)
Operating lease right-of-use assets		(8,712)		(8,817)
Unremitted foreign income		(10,536)		(10,567)
Total deferred tax liabilities		(56,736)		(64,832)
Total net deferred tax assets	$	83,041	$	64,145


	December 31,
	2024		2023
Deferred income taxes - net noncurrent assets	$	88,982	$	69,761
Deferred income taxes - net noncurrent liabilities		(5,941)		(5,616)
	$	83,041	$	64,145

Schedule of unrecognized tax benefits

A reconciliation of the Company’s unrecognized tax benefits is as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Unrecognized tax benefits at January 1	$	10,932	$	12,001	$	17,813
Increases related to current year tax positions		607		—		156
Increases related to prior period tax positions		53		52		40
Decreases related to the lapse of the applicable statute of limitations		(1,268)		(821)		(560)
Decreases related to prior period tax positions		(4,458)		(300)		(5,448)
Unrecognized tax benefits at December 31,	$	5,866	$	10,932	$	12,001

DEBT (Tables)

12 Months Ended

Dec. 31, 2024

DEBT

Schedule of long term debt


	December 31,
	2024			2023
Current portion of Term Debt	$	6,125		$	35,102

Long-term Debt, net of Current:
Long-term Debt, net of Current (Face Amount)	$	342,125		$	200,293
Original Issue Discount		(6,261)			—
Unamortized Debt Issuance Costs - Contra-Liability		(5,138)			(2,811)
Long-term Debt, net of Current	$	330,726		$	197,482

Total Face Amount of Borrowings	$	348,250		$	235,395

Unamortized Original Issue Discount and Debt Issuance Costs:
Other Assets	$	1,134		$	557
Long-Term Debt - Contra Liability		11,399			2,811
Total Unamortized Original Issue Discount and Debt Issuance Costs	$	12,533		$	3,368

Letters of Credit Outstanding	$	—		$	2,711

Remaining Borrowing Capacity	$	35,000		$	72,289

Average Interest Rates:
Term Loan		10.6	%		10.0	%
Letters of Credit		—	%		4.5	%

Schedule of debt maturities


Years ending December 31,
2025	$	6,125
2026		8,750
2027		13,125
2028		17,500
2029		302,750
	$	348,250

LEASES

12 Months Ended

Dec. 31, 2024

LEASES

LEASES

(21) LEASES

The Company has operating leases for corporate offices and research and development facilities and has historically had finance leases for certain equipment. Operating leases are reported separately in the Company’s consolidated balance sheets. Assets acquired under finance leases, if any, are included in Property and equipment, net, in the consolidated balance sheets.

The Company determines if an arrangement is a lease at inception. A contract is determined to contain a lease component if the arrangement provides the Company with a right to control the use of an identified asset. Lease agreements may include lease and non-lease components. In such instances for all classes of underlying assets, the Company does not separate lease and non-lease components but rather, accounts for the entire arrangement under leasing guidance. Leases with an initial term of 12 months or less are not recorded on the balance sheet and lease expense for these leases is recognized on a straight-line basis over the lease term.

Right-of-use assets and lease liabilities are initially measured based on the present value of the future minimum fixed lease payments (i.e., fixed payments in the lease contract) over the lease term at the commencement date. As the Company’s existing leases do not have a readily determinable implicit rate, the Company uses its incremental borrowing rate based on the information available at the commencement date in determining the present value of future minimum fixed lease payments. The Company calculates its incremental borrowing rate to reflect the interest rate that it would have to pay to borrow on a collateralized basis an amount equal to the lease payments in a similar economic environment over a similar term and considers its historical borrowing activities and market data from entities with comparable credit ratings in this determination. The measurement of the right-of-use asset also includes any lease payments made prior to the commencement date (excluding any lease incentives) and initial direct costs incurred. The Company assessed its right-of-use assets for impairment as of December 31, 2024 and 2023 and determined no impairment has occurred.

Lease terms may include options to extend or terminate the lease and the Company incorporates such options in the lease term when it has the unilateral right to make such an election and it is reasonably certain that the Company will exercise that option. In making this determination, the Company considers its prior renewal and termination history and planned usage of the assets under lease, incorporating expected market conditions.

For operating leases, lease expense for minimum fixed lease payments is recognized on a straight-line basis over the lease term. The expense for finance leases includes both interest and amortization expense components, with the interest component calculated based on the effective interest method and the amortization component calculated based on straight-line amortization of the right-of-use asset over the lease term. Lease contracts may contain variable lease costs, such as common area maintenance, utilities and tax reimbursements that vary over the term of the contract. Variable lease costs are not included in minimum fixed lease payments and as a result, are excluded from the measurement of the right-of-use assets and lease liabilities. The Company expenses all variable lease costs as incurred.

Certain leased facilities are being partially or fully vacated as part of the 2022 Restructuring Plan and for some of those facilities, the Company has no plans to enter into sublease agreements. Accordingly, the Company accelerated the amortization of those lease assets through the planned cease-use date of each facility, resulting in additional amortization expense of $1.0 million and $1.6 million in the years ended December 31, 2023 and 2022, respectively. No additional amortization was recorded in the year ended December 31, 2024. No variable lease costs were accrued in the years ended December 31, 2024 or 2023 for future estimated variable expenses related to assets partially or fully vacated with no intent or ability to sublease. Variable lease costs for the year ended December 31, 2022 included accruals of $1.0 million for all estimated future variable lease costs related to those facilities.

All incremental accelerated amortization and accrual for all estimated future variable lease costs are included in Restructuring and related expense in the Company’s consolidated statements of operations for the years ended December 31, 2024, 2023 and 2022. At December 31, 2024 and 2023, the Company had accruals of $1.1 million and $1.5 million, respectively, for all future anticipated variable lease costs related to these facilities. The Company may incur additional future expense if it is unable to sublease other locations included in the Facilities Initiative.

The Company leases its corporate offices and other facilities under operating leases, which expire at various times through 2033.

The Company’s right-of-use lease assets and lease liabilities at December 31, 2024 and 2023 were as follows (in thousands):


		December 31,
	Classification	2024		2023
Assets:
Operating lease assets	Operating lease right-of-use assets	$	34,544	$	39,783

Liabilities:
Current Operating	Operating lease liabilities	$	9,443	$	15,739
Non-Current Operating	Operating lease liabilities, net of current		37,376		38,711
Total Operating lease liabilities		$	46,819	$	54,450

The components of lease expense for the years ended December 31, 2024, 2023 and 2022 were as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Operating lease cost*	$	16,637	$	18,767	$	21,121
Finance lease cost:
Amortization of leased assets		—		—		287
Interest on lease liabilities		—		—		13
Short-term lease cost		13,616		13,978		14,209
Variable lease costs (costs excluded from minimum fixed lease payments)**		3,308		3,364		4,007
Sublease income		(788)		(1,376)		(1,647)
Net lease cost	$	32,773	$	34,733	$	37,990

Cash flow information related to the Company’s leases for the years ended December 31, 2024, 2023 and 2022 was as follows (in thousands):


	Year ended December 31,
	2024		2023			2022
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	18,619	$	19,021	$	20,363
Operating cash flows from finance leases	$	—	$	—	$	13
Financing cash flows from finance leases	$	—	$	—	$	595

Other information related to the Company’s leases as of December 31, 2024 and 2023 was as follows (in thousands):


	December 31,		December 31,
	2024		2023
Weighted average remaining lease term (years):
Operating leases	5.35		5.50
Weighted average discount rate:
Operating leases	7.73	%	6.34	%

Future minimum fixed lease payments under noncancelable leases at December 31, 2024 were as follows (in thousands):


	Operating
	leases
2025	$	12,654
2026		11,549
2027		10,221
2028		7,905
2029		5,620
2030 and beyond		9,037
Total lease payments		56,986
Less: interest		(10,167)
Present value of lease liabilities	$	46,819

LEASES - Components of Lease Expense (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
LEASES
Operating lease cost	$ 16,637,000	$ 18,767,000	$ 21,121,000
Finance lease cost:
Amortization of leased assets			287,000
Interest on lease liabilities			13,000
Short-term lease cost	13,616,000	13,978,000	14,209,000
Variable lease costs (costs excluded from minimum fixed lease payments)	3,308,000	3,364,000	4,007,000
Sublease income	(788,000)	(1,376,000)	(1,647,000)
Net lease cost	32,773,000	34,733,000	37,990,000
Accelerated amortization	0	1,000,000	1,600,000
Variable lease cost accrued	$ 0	$ 0	$ 1,000,000

REVENUE RECOGNITION - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
REVENUE RECOGNITION
Revenue recognized	$ 110.0	$ 108.0
Unearned revenue to be recognized	$ 285.0
Expected revenue, remaining performance obligation, period	3 years
Customer contract expected life (in years)	5 years
Deferred sales commissions capitalized	$ 2.8	$ 3.0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
REVENUE RECOGNITION
Revenue to be recognized	$ 10.0
Revenue, remaining performance obligation, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
REVENUE RECOGNITION
Revenue to be recognized	$ 5.0
Revenue, remaining performance obligation, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
REVENUE RECOGNITION
Revenue to be recognized	$ 6.0
Revenue, remaining performance obligation, period	1 year

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (54,235)	$ (66,206)	$ (98,083)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Impact of Derivative Financial Instrument on Condensed Consolidated Statement of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Gain (loss) recognized in other comprehensive income (loss) on swap, net of tax		$ (2,715)
Unrealized gain (loss) on interest rate swap, net of reclassifications and amortization	$ (6,019)	(15,114)
Other Income
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Amount reclassified from accumulated other comprehensive income to interest expense		(5,099)
Interest Expense
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Amount reclassified from accumulated other comprehensive income to interest expense	$ (6,019)	$ (7,300)

NATURE OF THE BUSINESS

12 Months Ended

Dec. 31, 2024

NATURE OF THE BUSINESS

NATURE OF THE BUSINESS

(1) NATURE OF THE BUSINESS

Ribbon Communications Inc. (“Ribbon” or the “Company”) is a leading global provider of communications technology to service providers and enterprises. The Company provides a broad range of software and high-performance hardware products, network solutions, and services that enable the secure delivery of data and voice communications, and high-bandwidth networking and connectivity for residential consumers and for small, medium, and large enterprises and industry verticals such as finance, education, government, utilities, and transportation. Ribbon’s mission is to create a recognized global technology leader providing cloud-centric solutions that enable the secure exchange of information, with unparalleled scale, performance, and elasticity. The Company is headquartered in Plano, Texas, and has a global presence with research and development, or sales and support locations in over thirty countries around the world.

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS - Changes in plan assets and benefit obligations recognized in other comprehensive income (loss) before tax (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
Net (gain) loss	$ (432)	$ 22	$ (4,666)
Amortization of net gain (loss)	150	165	(275)
Amortization of prior service credit (cost)	320	320	320
Settlement credit (charge)	234	417	(808)
Total recognized in other comprehensive income (loss)	$ 272	$ 924	$ (5,429)

DEBT - Debt maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
DEBT
2025	$ 6,125
2026	8,750
2027	13,125
2028	17,500
2029	302,750
Total Debt	$ 348,250	$ 235,395

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

RELATED PARTIES

12 Months Ended

Dec. 31, 2024

RELATED PARTIES

RELATED PARTIES

(25) RELATED PARTIES

The Company recognized revenue from its largest stockholder of $11.3 million, $12.8 million and $6.6 million in the years ended December 31, 2024, 2023 and 2022, respectively. The Company’s accounts receivable from its largest shareholder totaled $5.5 million and $3.9 million as of December 31, 2024 and 2023, respectively. Additionally, as discussed in Note 16, certain related party stockholders participated in the Private Placement.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-6

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(e))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-6

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

+ Details

INTANGIBLE ASSETS AND GOODWILL

12 Months Ended

Dec. 31, 2024

INTANGIBLE ASSETS AND GOODWILL

INTANGIBLE ASSETS AND GOODWILL

(10) INTANGIBLE ASSETS AND GOODWILL

The Company’s intangible assets at December 31, 2024 and 2023 consisted of the following (in thousands):


	Weighted
	average
	amortization					Net
	period			Accumulated		carrying
December 31, 2024	(years)	Cost		amortization		value
Developed technology	7.84	$	340,380	$	262,085	$	78,295
Customer relationships	11.86		268,140		160,635		107,505
Trade names	3.88		5,000		4,978		22
Software licenses	3.00		5,748		4,033		1,715
	9.50	$	619,268	$	431,731	$	187,537


	Weighted
	average
	amortization					Net
	period			Accumulated		carrying
December 31, 2023	(years)	Cost		amortization		value
Developed technology	7.84	$	340,380	$	239,066	$	101,314
Customer relationships	11.86		268,140		134,743		133,397
Trade names	3.88		5,000		4,901		99
Software licenses	3.00		5,436		2,159		3,277
	9.51	$	618,956	$	380,869	$	238,087

Estimated future amortization expense for the Company’s intangible assets at December 31, 2024 was as follows (in thousands):


Years ending December 31,
2025	$	44,192
2026		39,143
2027		33,979
2028		23,400
2029		18,379
Thereafter		28,444
	$	187,537

Goodwill is recorded when the consideration for an acquisition exceeds the fair value of net tangible and identifiable intangible assets acquired. For the purpose of testing goodwill for impairment, all goodwill is assigned to a reporting unit, which may be either an operating segment or a portion of an operating segment. The Company’s reporting units are its two operating segments, Cloud and Edge and IP Optical Networks. Testing for impairment of goodwill is completed annually as of October 1^st. The Company’s IP Optical Networks operating segment, with $76.0 million of associated goodwill, had a negative carrying value and a positive fair value as of October 1, 2024.

Upon completion of the 2024 and 2023 annual tests for goodwill impairment, the Company determined that there was no impairment of goodwill in either of its reporting units. There was no change in the carrying value of the Company’s goodwill in the years ended December 31, 2024 and 2023.

The components of goodwill at December 31, 2024 and 2023 were as follows (in thousands):


	Cloud and		IP Optical
	Edge		Networks		Total
Goodwill	$	392,302	$	191,996	$	584,298
Accumulated impairment losses		(167,406)		(116,000)		(283,406)
	$	224,896	$	75,996	$	300,892

ACCRUED EXPENSES AND OTHER

12 Months Ended

Dec. 31, 2024

ACCRUED EXPENSES AND OTHER

ACCRUED EXPENSES AND OTHER

(11) ACCRUED EXPENSES AND OTHER

Accrued expenses and other consisted of the following (in thousands):


	December 31,		December 31,
	2024		2023
Employee compensation and related costs	$	44,948	$	33,682
Professional fees		16,339		19,702
Taxes payable		6,364		8,383
Other		38,600		29,920
	$	106,251	$	91,687

PROPERTY AND EQUIPMENT - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
PROPERTY AND EQUIPMENT
Property and equipment, assets not yet commenced depreciation	$ 23,200	$ 3,400
Depreciation and amortization of property and equipment	13,539	14,105	$ 15,295
Leasehold improvements and equipment
PROPERTY AND EQUIPMENT
Property and equipment, assets not yet commenced depreciation	$ 18,900	$ 500

ACCOUNTS RECEIVABLE, NET - Allowance for doubtful accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
ACCOUNTS RECEIVABLE, NET
Balance at beginning of year	$ 1,512	$ 1,427	$ 1,270
Charges to expense	152	428	100
Charges (credits) to other accounts	(75)	143	159
Write-offs	(133)	(486)	(102)
Balance at end of year	$ 1,456	$ 1,512	$ 1,427

INCOME TAXES - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
INCOME TAXES - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
INCOME TAXES
Tax credit carryforwards	$ 25,400
Significant change in shareholder ownership (in years)	3 years
Significant change in shareholder ownership (in percentage)	50.00%
Deferred tax assets, valuation allowance	$ 493,855	$ 488,799
Deferred tax assets	6,700	14,000	$ 14,900
Unrecognized tax benefits that would impact effective tax rate	3,600	10,500	11,200
Unrecognized tax benefits including penalties and interest expense	(2,200)	200	$ (300)
Decrease in unrecognized tax benefits is reasonably possible	400
Accrued expenses and other
INCOME TAXES
Deferred tax assets	900	3,200
Edgewater
INCOME TAXES
U.S federal net operating losses carryforwards	92,800
Annual limitation	9,700
ECI
INCOME TAXES
U.S federal net operating losses carryforwards	9,600
Annual limitation	1,100
Domestic tax authority
INCOME TAXES
U.S federal net operating losses	100,200
Deferred tax assets, valuation allowance	18,600	23,400
State and local jurisdiction
INCOME TAXES
U.S federal net operating losses	51,000
Israel
INCOME TAXES
U.S federal net operating losses	1,600,000
Foreign tax authority
INCOME TAXES
Deferred tax assets, valuation allowance	$ 475,000	$ 465,000

PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
PROPERTY AND EQUIPMENT
Property and equipment, gross	$ 179,426	$ 151,691
Less accumulated depreciation and amortization	(119,062)	(109,871)
Property and equipment, net	$ 60,364	41,820
Minimum
PROPERTY AND EQUIPMENT
Property and equipment, useful life (in years)	2 years
Maximum
PROPERTY AND EQUIPMENT
Property and equipment, useful life (in years)	5 years
Equipment
PROPERTY AND EQUIPMENT
Property and equipment, gross	$ 84,409	77,205
Equipment \| Minimum
PROPERTY AND EQUIPMENT
Property and equipment, useful life (in years)	2 years
Equipment \| Maximum
PROPERTY AND EQUIPMENT
Property and equipment, useful life (in years)	5 years
Software
PROPERTY AND EQUIPMENT
Property and equipment, useful life (in years)	3 years
Property and equipment, gross	$ 36,859	34,802
Software \| Minimum
PROPERTY AND EQUIPMENT
Property and equipment, useful life (in years)	2 years
Software \| Maximum
PROPERTY AND EQUIPMENT
Property and equipment, useful life (in years)	5 years
Furniture and fixtures
PROPERTY AND EQUIPMENT
Property and equipment, gross	$ 3,309	3,301
Furniture and fixtures \| Minimum
PROPERTY AND EQUIPMENT
Property and equipment, useful life (in years)	3 years
Furniture and fixtures \| Maximum
PROPERTY AND EQUIPMENT
Property and equipment, useful life (in years)	5 years
Leasehold improvements
PROPERTY AND EQUIPMENT
Property and equipment, useful life (in years)	5 years
Property and equipment, gross	$ 54,849	$ 36,383

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
Defined benefit plans	$ 22,137,000	$ 20,769,000	$ 21,257,000
Net gains and losses amortization threshold (in percent)	10.00%
Fair value of combined plan assets	$ 14,486,000	13,609,000	14,629,000
Participant contributions	$ 29,000	39,000
Fixed contributions per employee (in percent)	5.00%
Employer pension plan contributions	$ 707,000	975,000	2,000,000
Employer contributions to pension plans	1,500,000
Israel
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
Defined benefit plans	900,000
Switzerland
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
Fair value of combined plan assets	2,800,000	2,600,000
Netherlands
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
Fair value of combined plan assets	$ 0	$ 0	$ 0

DEBT

12 Months Ended

Dec. 31, 2024

DEBT

DEBT

(14) DEBT

2024 Credit Facility

On June 21, 2024, the Company entered into a Senior Secured Credit Facilities Credit Agreement (the “2024 Credit Facility” or “Credit Agreement”) as guarantor, with the Company’s wholly-owned subsidiary, Ribbon Communications Operating Company, Inc., as the borrower (the “Borrower”), HPS Investment Partners, LLC ("HPS"), as administrative agent, and HPS and WhiteHorse Capital Management, LLC ("WhiteHorse" and, together with HPS, the "Lenders"), pursuant to which the Lenders provided the Company with a $385 million Credit Agreement comprised of (i) a $350 million term loan (the “2024 Term Loan”) and (ii) a $35 million revolving credit facility (the “2024 Revolver”), including a $20 million sublimit for letters of credit. The proceeds received from the 2024 Term Loan were used to (a) repay 100% of the amounts outstanding under the 2020 Credit Facility, (b) redeem in full the Preferred Stock and (c) pay fees and expenses related to the 2024 Credit Facility. The excess proceeds are being used by the Company for working capital and other general corporate purposes.

The 2024 Term Loan and the 2024 Revolver bear interest, at the Borrower’s option, at either the Alternate Base Rate (“ABR”) or Term Secured Overnight Financing Rate ("SOFR") with an Applicable Margin for each (all as defined in the 2024 Credit Facility). Margins for the first six months are 5.25% per annum for ABR Loans and 6.25% per annum for SOFR Loans. Thereafter, margins vary based on the Company’s Consolidated Net Leverage Ratio, ranging from 4.75% to 5.25% per annum for ABR Loans and 5.75% to 6.25% per annum for SOFR Loans. The 2024 Term Loan and the 2024 Revolver will both mature on June 21, 2029. The 2024 Term Loan is being repaid in equal quarterly installments: approximately $0.9 million beginning with the third quarter of 2024 through the second quarter of 2025; approximately $2.2 million beginning with the third quarter of 2025 and ending with the second quarter of 2027; and approximately $4.4 million quarterly thereafter, with the remaining principal balance of approximately $298.4 million due on the maturity date of June 21, 2029. In connection with the establishment of the 2024 Credit Facility, $7.7 million of original issue discount was withheld by the Lenders and the Company incurred $6.3 million of debt issuance costs for a total of $14.0 million that is being amortized to Interest expense, net over the term of the 2024 Credit Facility.

The 2024 Credit Facility requires compliance with a Maximum Consolidated Net Leverage Ratio (the "Financial Covenant"), as defined in the 2024 Credit Facility, which is tested on a quarterly basis. The Company was in compliance with the Financial Covenant as of December 31, 2024.

The indebtedness and other obligations under the 2024 Credit Facility are irrevocably and unconditionally guaranteed on a joint and several basis by the Company and its subsidiaries (together, the "Guarantors"). The 2024 Credit Facility is secured on a first-priority basis by liens on substantially all assets of the Borrower and the Guarantors.

2020 Credit Facility

On June 21, 2024, the Company used the proceeds from the 2024 Credit Facility to, among other things, repay all amounts outstanding under its Senior Secured Credit Facilities Credit Agreement, dated March 3, 2020 (as amended, the "2020 Credit Facility"), by and among the Company, as a guarantor, Ribbon Communications Operating Company, Inc., as the borrower (the "Borrower"), Citizens Bank, N.A., Santander Bank, N.A., and others as lenders ("2020 Credit Facility Lenders"). The Company wrote off $2.0 million of debt issuance costs in conjunction with the early extinguishment of the 2020 Credit Facility.

On March 3, 2020, the Company entered into a Senior Secured Credit Facilities Credit Agreement (as amended, the “2020 Credit Facility”), by and among the Company, as a guarantor, Ribbon Communications Operating Company, Inc., as the borrower (“Borrower”), Citizens Bank, N.A. (“Citizens”), Santander Bank, N.A., and others as lenders, (“Lenders”). The proceeds of the Credit Agreement were used, in part, to pay off in full all obligations of the Company under the 2019 Credit Facility.

The 2020 Credit Facility had a maturity date of March 2025 and originally provided for $500 million of commitments from the 2020 Credit Facility Lenders to the Borrower, comprised of $400 million in term loans (the “2020 Term Loan Facility”) and a $100 million facility available for revolving loans (the “2020 Revolving Credit Facility”). Under the 2020 Revolving Credit Facility, a $30 million sublimit was originally available for letters of credit and a $20 million sublimit was available for swingline loans.

The indebtedness and other obligations under the 2020 Credit Facility were unconditionally guaranteed on a senior secured basis by the Company, Edgewater Networks, Inc., a wholly-owned subsidiary of the Company, and GENBAND Inc., wholly-owned subsidiary of the Company (together, the “2020 Credit Facility Guarantors”). The 2020 Credit Facility was secured by first-priority liens on substantially all of the assets of the Borrower and the 2020 Credit Facility Guarantors, including substantially all of the assets of the Company.

The 2020 Credit Facility required compliance with certain financial covenants, including a minimum Consolidated Fixed Charge Coverage Ratio and a maximum Consolidated Net Leverage Ratio (each as defined in the 2020 Credit Facility, and each tested on a quarterly basis).

On March 10, 2022, the Company entered into the Fourth Amendment to the 2020 Credit Facility to increase the Maximum Consolidated Net Leverage Ratio (as defined in the 2020 Credit Facility) and in conjunction, the Company made a $15.0 million prepayment that was applied to the final payment due on the maturity date.

On June 30, 2022, the Company entered into the Fifth Amendment to the 2020 Credit Facility (the “Fifth Amendment”) to increase the Maximum Consolidated Net Leverage Ratio (as defined in the 2020 Credit Facility) for 2022, with the fourth quarter of 2022 increased to 4.75:1.00, the first and second quarters of 2023 declining to 3.25:1.00, and in all subsequent quarters the ratio was to be fixed at 3.00:1.00. Also, the Fifth Amendment reduced the minimum Consolidated Fixed Charge Coverage Ratio (as defined in the 2020 Credit Facility) in 2022, with the fourth quarter of 2022 reduced to 1.10:1.00 and in all subsequent quarters the ratio was to be fixed at 1.25:1.00. In addition, the Fifth Amendment increased the maximum rate at which loans were to bear interest if the Company’s Consolidated Net Leverage Ratio for any quarter was greater than 4.50:1.00. Specifically, loans incurred were to bear interest, at the Borrower’s option, at either LIBOR plus a margin ranging from 1.50% to 4.50% per year, or the base rate plus 0.50%, or the prime rate plus a margin ranging from 0.50% to 3.50% per year. The Fifth Amendment also allowed the Company to incur junior secured or unsecured debt in an amount no less than $50 million, subject to certain conditions, including the requirement that 50% of the aggregate amount of such incurred debt (net of certain costs, fees and other amounts) must be applied to prepay the 2020 Credit Facility, and compliance with certain leverage ratio-based covenant exceptions. In connection with the Fifth Amendment, the Company made a $10.0 million voluntary prepayment that was applied to the final payment due on the maturity date. Subsequent to the Fifth Amendment, the Company was required to make

quarterly principal payments on the 2020 Term Loan aggregating approximately $5.0 million per quarter through March 31, 2024 and $10.0 million in each of the three quarters thereafter, with the remaining and final payment due on the maturity date in March 2025.

On March 24, 2023, the Company entered into the Sixth Amendment to the 2020 Credit Facility (the “Sixth Amendment”) effective March 30, 2023. The Sixth Amendment, among other things, increased the Maximum Consolidated Net Leverage Ratio (as defined in the 2020 Credit Facility), for the first, second and third quarters of 2023 to 4.50:1.00. In the fourth quarter of 2023 and the first quarter of 2024, the Maximum Consolidated Net Leverage Ratio declined to 4.25:1.00 and 4.00:1.00, respectively. Also, the Sixth Amendment reduced the minimum Consolidated Fixed Charge Coverage Ratio (as defined in the 2020 Credit Facility) to 1.10:1.00 through the first quarter of 2024. The Sixth Amendment reduced the maximum borrowings allowed under the 2020 Revolving Credit Facility from $100 million to $75 million and the sublimit available for letters of credit was reduced from $30 million to $20 million. In addition, the Sixth Amendment replaced LIBOR with SOFR as the alternative rate available to the Company for calculating interest owed under the 2020 Credit Facility with the margin fixed at 4.5%. In conjunction with the Sixth Amendment, the Company made a $75 million prepayment that was applied to the final payment due upon maturity in March 2025. The $75 million prepayment was almost entirely funded with the net proceeds from the Private Placement and the sales of the Company’s interest rate swap. Debt issuance costs associated with the Sixth Amendment totaled $1.7 million and were being amortized on a straight-line basis over the remaining life of the 2020 Credit Facility and were written off in conjunction with the early extinguishment of the 2020 Credit Facility on June 21, 2024.

The Company’s interest rates under the 2020 Term Loan benefited from a hedge instrument that was in place, specifically a fixed rate swap, until it was sold in March 2023 (see Note 15). Following the sale of the fixed rate swap in March 2023, the Company’s interest rate was based upon U.S. dollar SOFR plus a fixed margin of 4.5%. The Company

was in compliance with all covenants of the 2020 Credit Facility at December 31, 2023, including the Consolidated Net Leverage Ratio calculation that considered the Company’s debt to include Preferred Stock.

The Company had the following outstanding borrowings, unamortized debt issuance costs and original issue discount, letters of credit, interest rates, and remaining borrowing capacity under the 2024 Credit Facility and the 2020 Credit Facility as of December 31, 2024 and 2023, respectively:


	December 31,
	2024			2023
Current portion of Term Debt	$	6,125		$	35,102

Long-term Debt, net of Current:
Long-term Debt, net of Current (Face Amount)	$	342,125		$	200,293
Original Issue Discount		(6,261)			—
Unamortized Debt Issuance Costs - Contra-Liability		(5,138)			(2,811)
Long-term Debt, net of Current	$	330,726		$	197,482

Total Face Amount of Borrowings	$	348,250		$	235,395

Unamortized Original Issue Discount and Debt Issuance Costs:
Other Assets	$	1,134		$	557
Long-Term Debt - Contra Liability		11,399			2,811
Total Unamortized Original Issue Discount and Debt Issuance Costs	$	12,533		$	3,368

Letters of Credit Outstanding	$	—		$	2,711

Remaining Borrowing Capacity	$	35,000		$	72,289

Average Interest Rates:
Term Loan		10.6	%		10.0	%
Letters of Credit		—	%		4.5	%

The Company’s debt maturities as of December 31, 2024 were as follows:


Years ending December 31,
2025	$	6,125
2026		8,750
2027		13,125
2028		17,500
2029		302,750
	$	348,250

Letters of Credit and Other Guarantees

The Company uses letters of credit, bank guarantees, and surety bonds in the course of its business. At December 31, 2024, the Company had $10.9 million of letters of credit, bank guarantees, and surety bonds outstanding (collectively, "Guarantees") under various uncommitted facilities and no letters of credit outstanding under the 2024 Credit Facility. At December 31, 2023, the Company had Guarantees aggregating $7.9 million, comprised of the $2.7 million of letters of credit under the 2020 Credit Facility described above and $5.2 million of Other Guarantees. At December 31, 2024 and 2023, the Company had cash collateral of $2.7 million and $0.1 million, respectively, supporting the Guarantees, which are reported in Restricted cash in the Company’s consolidated balance sheets.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/470/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1C

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1C

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1C

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

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-Publisher FASB
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Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

+ Details

ACCOUNTS RECEIVABLE, NET

12 Months Ended

Dec. 31, 2024

ACCOUNTS RECEIVABLE, NET

ACCOUNTS RECEIVABLE, NET

(7) ACCOUNTS RECEIVABLE, NET

Accounts receivable, net, consisted of the following (in thousands):


	December 31,
	2024		2023
Accounts receivable	$	256,174	$	269,933
Allowance for doubtful accounts		(1,456)		(1,512)
Accounts receivable, net	$	254,718	$	268,421

The Company’s allowance for doubtful accounts activity was as follows (in thousands):


					Charges
	Balance at				(credits) to				Balance at
	beginning		Charges		other				end of
Year ended December 31,	of year		to expense		accounts		Write-offs		year
2024	$	1,512	$	152	$	(75)	$	(133)	$	1,456
2023	$	1,427	$	428	$	143	$	(486)	$	1,512
2022	$	1,270	$	100	$	159	$	(102)	$	1,427

DEBT - Credit facilities (Details) $ in Thousands					12 Months Ended
DEBT - Credit facilities (Details) $ in Thousands	Jun. 21, 2024 USD ($)	Mar. 24, 2023 USD ($)	Jun. 30, 2022 USD ($)	Mar. 10, 2022 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
DEBT
Amortization of debt issuance costs and original issue discount					$ 4,847	$ 3,241	$ 2,308
Repayment of principal					$ 44,106	$ 97,000	$ 73,625
2020 credit facility
DEBT
Commitments from lender	$ 500,000
Percentage of debt repaid or redeemed	100.00%
Write off of capitalized debt issuance costs	$ 2,000
Repayment of principal			$ 10,000	$ 15,000
Consolidated net leverage ratio		1.1
Accordion feature			$ 50,000
Percent of aggregate amount applied for repayment			50.00%
2020 credit facility \| Debt Instrument, Period Five
DEBT
Consolidated net leverage ratio			1.25
2020 credit facility \| Debt Instrument, Period Four
DEBT
Consolidated net leverage ratio			1.1
2020 credit facility \| Maximum \| Debt Instrument, Period Five
DEBT
Consolidated net leverage ratio			4.5
2020 credit facility \| Maximum \| Debt Instrument, Period One
DEBT
Consolidated net leverage ratio		4.5	4.75
2020 credit facility \| Maximum \| Debt Instrument, Period Two
DEBT
Consolidated net leverage ratio		4.25	3.25
2020 credit facility \| Maximum \| Debt Instrument, Period Three
DEBT
Consolidated net leverage ratio		4	3
2024 Credit Agreement
DEBT
Commitments from lender	385,000
Revolving Credit Facility \| 2020 credit facility
DEBT
Commitments from lender	100,000
Debt issuance costs, gross		$ 1,700
Repayments of debt		75,000
Revolving Credit Facility \| 2020 credit facility \| Minimum
DEBT
Commitments from lender		75,000
Revolving Credit Facility \| 2020 credit facility \| Maximum
DEBT
Commitments from lender		$ 100,000
Revolving Credit Facility \| 2024 Credit Agreement
DEBT
Commitments from lender	$ 35,000
Revolving Credit Facility \| 2024 Credit Agreement \| SOFR
DEBT
Basis spread on variable rate	6.25%
Revolving Credit Facility \| 2024 Credit Agreement \| Minimum \| SOFR \| Line of credit
DEBT
Basis spread on variable rate	5.75%
Revolving Credit Facility \| 2024 Credit Agreement \| Maximum \| SOFR \| Line of credit
DEBT
Basis spread on variable rate	6.25%
Term loan facility \| 2020 credit facility
DEBT
Commitments from lender	$ 400,000
Term loan facility \| 2024 Credit Agreement
DEBT
Commitments from lender	350,000
Remaining principal payable at maturity	298,400
Unamortized Discount	7,700
Debt issuance costs, gross	6,300
Amortization of debt issuance costs and original issue discount	14,000
Term loan facility \| 2024 Credit Agreement \| Debt Instrument, Period One
DEBT
Quarterly principal payment amount	900
Term loan facility \| 2024 Credit Agreement \| Debt Instrument, Period Two
DEBT
Quarterly principal payment amount	2,200
Term loan facility \| 2024 Credit Agreement \| Debt Instrument, Period Three
DEBT
Quarterly principal payment amount	$ 4,400
Term loan facility \| 2024 Credit Agreement \| Alternate Base Rate
DEBT
Basis spread on variable rate	5.25%
Term loan facility \| 2024 Credit Agreement \| Minimum \| Alternate Base Rate
DEBT
Basis spread on variable rate	4.75%
Term loan facility \| 2024 Credit Agreement \| Maximum \| Alternate Base Rate
DEBT
Basis spread on variable rate	5.25%
Letters of Credit
DEBT
Debt interest rate						4.50%
Letters of Credit \| 2020 credit facility
DEBT
Commitments from lender	$ 30,000
Debt interest rate		4.50%
Letters of Credit \| 2020 credit facility \| SOFR
DEBT
Basis spread on variable rate					4.50%
Letters of Credit \| 2020 credit facility \| Minimum
DEBT
Commitments from lender		$ 20,000
Letters of Credit \| 2020 credit facility \| Maximum
DEBT
Commitments from lender		$ 30,000
Letters of Credit \| 2024 Credit Agreement
DEBT
Commitments from lender	20,000
Swingline Loan \| 2020 credit facility
DEBT
Commitments from lender	$ 20,000
Term Loan Facility, Term B Loan \| Minimum \| Prime Rate
DEBT
Basis spread on variable rate			0.50%
Term Loan Facility, Term B Loan \| Maximum \| Prime Rate
DEBT
Basis spread on variable rate			3.50%
Term Loan Facility, Term B Loan \| 2020 credit facility \| Minimum \| LIBOR
DEBT
Basis spread on variable rate			1.50%
Term Loan Facility, Term B Loan \| 2020 credit facility \| Maximum \| Prime Rate
DEBT
Basis spread on variable rate			0.50%
Term Loan Facility, Term B Loan \| 2020 credit facility \| Maximum \| LIBOR
DEBT
Basis spread on variable rate			4.50%
2020 Term Loan
DEBT
Repayment of debt per quarter through March 31, 2024			$ 5,000
Repayment of debt for three quarters, thereafter			$ 10,000

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Tables)

12 Months Ended

Dec. 31, 2024

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES

Schedule of impact of derivative financial instrument on condensed consolidated statement of operations

The impact of the Company’s derivative financial instrument on its consolidated statements of comprehensive loss for the years ended December 31, 2024 and 2023 was as follows, net of tax (in thousands):


	Year ended December 31,
	2024		2023
Gain (loss) recognized in other comprehensive income (loss) on swap, net of tax	$	—	$	(2,715)
Amount reclassified from accumulated other comprehensive income to other expense, net upon sale of swap, net of tax		—		(5,099)
Amount reclassified from accumulated other comprehensive income to interest expense		(6,019)		(7,300)
Unrealized gain (loss) on interest rate swap, net of reclassifications and amortization	$	(6,019)	$	(15,114)

WARRANTY - Changes in Accrual Balance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Changes in the company's accrual balance
Balance at beginning of year	$ 12,243	$ 11,857
Provision	5,423	5,875
Settlements	(5,366)	(5,489)
Balance at end of year	$ 12,300	$ 12,243

OPERATING SEGMENT INFORMATION (Tables)

12 Months Ended

Dec. 31, 2024

OPERATING SEGMENT INFORMATION

Schedule of segment reporting information

The tables below present significant segment expenses regularly reviewed by the CODM for the years ended December 31, 2024, 2023 and 2022 (in thousands):


	Year ended December 31,
	2024		2023		2022
Segment revenue:
Cloud and Edge	$	505,157	$	477,647	$	508,137
IP Optical Networks		328,724		348,692		311,623
Revenue	$	833,881	$	826,339	$	819,760


	Year ended December 31,
	2024		2023		2022
Segment cost of revenue:
Cloud and Edge	$	175,940	$	177,629	$	197,840
IP Optical Networks		218,429		240,627		220,984
Cost of revenue	$	394,369	$	418,256	$	418,824


	Year ended December 31,
	2024		2023		2022
Segment adjusted gross profit:
Cloud and Edge	$	338,194	$	314,594	$	330,395
IP Optical Networks		127,836		124,436		104,711
Total segment adjusted gross profit		466,030		439,030		435,106

Reconciliation of segment adjusted gross profit to gross profit and loss before income taxes
Stock-based compensation expense		(1,625)		(2,657)		(2,628)
Amortization of acquired technology		(24,893)		(28,290)		(31,542)
Gross profit		439,512		408,083		400,936

Research and development expense		179,941		190,660		203,676
Sales and marketing expense		137,830		137,460		147,766
General and administrative expense		68,740		54,962		51,053
Amortization of acquired intangible assets		25,969		28,601		29,646
Acquisition-, disposal- and integration-related expense		—		4,476		6,286
Restructuring and related expense		10,160		16,209		10,833
Interest expense, net		33,821		27,320		19,780
Other expense, net		29,119		3,768		44,495
Loss before income taxes	$	(46,068)	$	(55,373)	$	(112,599)


	Year ended December 31,
	2024		2023		2022
Segment depreciation expense:
Cloud and Edge	$	9,337	$	9,798	$	10,758
IP Optical Networks		4,202		4,307		4,537
Depreciation expense	$	13,539	$	14,105	$	15,295

FAIR VALUE HIERARCHY

12 Months Ended

Dec. 31, 2024

FAIR VALUE HIERARCHY

FAIR VALUE HIERARCHY

(6) FAIR VALUE HIERARCHY

Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. The three-tier fair value hierarchy is based on the level of independent, objective evidence surrounding the inputs used to measure fair value. A financial instrument’s categorization within the fair value hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The fair value hierarchy is as follows:

●

Level 1 applies to assets or liabilities for which there are quoted prices in active markets for identical assets or liabilities. The Company had no assets or liabilities fair valued using Level 1 input at December 31, 2024 or 2023.

●

Level 2 applies to assets or liabilities for which there are inputs that are directly or indirectly observable in the marketplace, such as quoted prices for similar assets or liabilities in active markets or quoted prices for identical assets or liabilities in markets with insufficient volume or infrequent transactions (less active markets). At December 31, 2024 and 2023, the Company determined the fair value of its defined benefit plans’ assets using Level 2 input.

●

Level 3 applies to assets or liabilities for which there are unobservable inputs to the valuation methodology that are significant to the measurement of the fair value of the assets or liabilities. At December 31, 2024, the fair value of the Company’s Warrants was determined using Level 3 input. At December 31, 2023, the fair value of the Company’s Preferred Stock and Warrants were determined using Level 3 input.

The Company did not have any transfers between Level 2 and Level 3 fair value measurements during the years ended December 31, 2024 and 2023.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
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-Name Accounting Standards Codification
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-Paragraph 100
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-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

SALE OF KANDY COMMUNICATIONS BUSINESS (Details) $ / shares in Units, $ in Thousands				12 Months Ended
	Sep. 08, 2021 shares	Feb. 19, 2021 D $ / shares	Dec. 01, 2020 USD ($) D $ / shares shares	Dec. 31, 2022 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Aug. 29, 2022 USD ($)
SALE OF KANDY COMMUNICATIONS BUSINESS
Intangible assets, net					$ 187,537	$ 238,087
Decrease in fair value of investments				$ 41,291
Software licenses
SALE OF KANDY COMMUNICATIONS BUSINESS
Intangible assets, net					1,715	3,277
Disposal Group, Disposed of by Sale, Not Discontinued Operations
SALE OF KANDY COMMUNICATIONS BUSINESS
Fair value of AVCT units					0	0	$ 2,600
Payments for settlement agreement							$ 2,500
Decrease in fair value of investments				$ 41,300
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Software licenses
SALE OF KANDY COMMUNICATIONS BUSINESS
Intangible assets, net					$ 1,000	$ 2,400
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Kandy Communications Business
SALE OF KANDY COMMUNICATIONS BUSINESS
Consideration from sale			$ 45,000
Number of AVCT Units acquired (in shares) \| shares			43,778
Promissory note interest rate			10.00%
Debenture, stock price trigger (in dollars per share) \| $ / shares		$ 6	$ 6
Debenture, number of trading days \| D		40	40
Debenture, number of consecutive trading days \| D		60	60
Debt conversion, converted instrument, shares issued (in shares) \| shares	13,700,421
Number of shares of common stock entitled from warrants (in shares) \| shares			4,377,800
Exercise price of warrants (in dollars per share) \| $ / shares			$ 0.01

LEASES - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Operating leases
2025	$ 12,654
2026	11,549
2027	10,221
2028	7,905
2029	5,620
2030 and beyond	9,037
Total lease payments	56,986
Less: interest	(10,167)
Present value of lease liabilities	$ 46,819	$ 54,450

OPERATING SEGMENT INFORMATION

12 Months Ended

Dec. 31, 2024

OPERATING SEGMENT INFORMATION

OPERATING SEGMENT INFORMATION

(18) OPERATING SEGMENT INFORMATION

The Company has two operating and reportable segments, Cloud and Edge and IP Optical Networks, that align with the way the business is managed. The Company’s CODM, its President and Chief Executive Officer, makes key operating decisions and assesses performance based upon these reportable segments.

The Cloud and Edge segment provides secure and reliable software and hardware products, solutions and services for enabling Voice over Internet Protocol ("VoIP") communications, Voice over Long-Term Evolution ("VoLTE") and Voice Over 5G ("VoNR") communications, and Unified Communications and Collaboration ("UC&C") within service provider and enterprise networks and from the cloud. The Cloud and Edge products are increasingly software-centric and cloud-native for deployment on private, public or hybrid cloud infrastructures, in data centers, on enterprise premises and within service provider networks. Ribbon's Cloud and Edge product portfolio consists primarily of its Session Border Controller ("SBC") products and its Network Transformation products.

The IP Optical Networks segment provides high-performance, secure solutions for IP networking and optical

transport, supporting wireless networks including 5G, metro and edge aggregation, core networking, data center interconnect, legacy transformation and transport solutions for wholesale carriers. This portfolio is offered to service provider, enterprise and industry verticals with critical transport network infrastructures including utilities, government, defense, transportation, and education and research.

The Company does not provide segment asset information as such information is not provided to the CODM and accordingly, asset information is not used in assessing segment performance. Segment revenue and expenses included in the tables below represent direct revenue and expense attributable to each segment. Please see Note 10 for information regarding the allocation of goodwill between segments.

The CODM utilizes adjusted gross profit to evaluate each segment's performance. The Company calculates adjusted gross profit by excluding from cost of revenue both amortization of acquired technology and stock-based compensation and may also exclude other items in future periods that the Company believes are not part of the Company's core business. The Company uses adjusted gross profit to develop its annual budget and quarterly forecasts. The CODM analyzes adjusted gross profit compared to the annual budget and quarterly forecasts to allocate resources. Ribbon’s calculation of adjusted gross profit may not be comparable to similarly titled measures used by other companies. See below for a reconciliation of segment adjusted gross profit to gross profit and loss before income taxes.

The tables below present significant segment expenses regularly reviewed by the CODM for the years ended December 31, 2024, 2023 and 2022 (in thousands):


	Year ended December 31,
	2024		2023		2022
Segment revenue:
Cloud and Edge	$	505,157	$	477,647	$	508,137
IP Optical Networks		328,724		348,692		311,623
Revenue	$	833,881	$	826,339	$	819,760


	Year ended December 31,
	2024		2023		2022
Segment cost of revenue:
Cloud and Edge	$	175,940	$	177,629	$	197,840
IP Optical Networks		218,429		240,627		220,984
Cost of revenue	$	394,369	$	418,256	$	418,824


	Year ended December 31,
	2024		2023		2022
Segment adjusted gross profit:
Cloud and Edge	$	338,194	$	314,594	$	330,395
IP Optical Networks		127,836		124,436		104,711
Total segment adjusted gross profit		466,030		439,030		435,106

Reconciliation of segment adjusted gross profit to gross profit and loss before income taxes
Stock-based compensation expense		(1,625)		(2,657)		(2,628)
Amortization of acquired technology		(24,893)		(28,290)		(31,542)
Gross profit		439,512		408,083		400,936

Research and development expense		179,941		190,660		203,676
Sales and marketing expense		137,830		137,460		147,766
General and administrative expense		68,740		54,962		51,053
Amortization of acquired intangible assets		25,969		28,601		29,646
Acquisition-, disposal- and integration-related expense		—		4,476		6,286
Restructuring and related expense		10,160		16,209		10,833
Interest expense, net		33,821		27,320		19,780
Other expense, net		29,119		3,768		44,495
Loss before income taxes	$	(46,068)	$	(55,373)	$	(112,599)


	Year ended December 31,
	2024		2023		2022
Segment depreciation expense:
Cloud and Edge	$	9,337	$	9,798	$	10,758
IP Optical Networks		4,202		4,307		4,537
Depreciation expense	$	13,539	$	14,105	$	15,295

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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-Topic 280
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+ Details

INCOME TAXES - Components of loss from continuing operations before income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income (loss) before income taxes:
United States	$ 22,685	$ (5,363)	$ (84,784)
Foreign	(68,753)	(50,010)	(27,815)
Loss before income taxes	$ (46,068)	$ (55,373)	$ (112,599)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

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+ Details

RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES
Restructuring and related	$ 10,160	$ 16,209	$ 10,833
Severance and related costs	4,036	9,875	$ 5,230
Restructuring reserve current	1,400	1,100
Restructuring reserve noncurrent	800	1,100
2024 Workforce Reductions
RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES
Severance and related costs	2,100
2023 Restructuring Initiative
RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES
Restructuring and related	2,000	9,900
2022 Restructuring Plan
RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES
Restructuring and related	6,100	6,334
Restructuring costs	5,000
Severance and related costs \| 2023 Restructuring Initiative
RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES
Restructuring and related	2,003	9,875
Variable and other facilities-related costs \| 2022 Restructuring Plan
RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES
Restructuring and related	6,123	5,326
Accelerated amortization of lease assets \| 2022 Restructuring Plan
RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES
Restructuring and related	$ 1,000	$ 1,008

REVENUE RECOGNITION - Schedule of Customer Assets & Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Accounts receivable
Beginning balance	$ 186,938	$ 170,969
Increase (decrease), net	(10,363)	15,969
Ending balance	176,575	186,938
Unbilled accounts receivable
Beginning balance	81,483	96,275
Increase (decrease), net	(3,340)	(14,792)
Ending balance	78,143	81,483
Deferred revenue (current)
Beginning balance	113,381	113,939
Increase (decrease), net	5,914	(558)
Ending balance	119,295	113,381
Deferred revenue (long-term)
Beginning balance	19,218	19,254
Increase (decrease), net	1,773	(36)
Ending balance	$ 20,991	$ 19,218

EARNINGS (LOSS) PER SHARE - Narrative (Details) - $ / shares shares in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Employee Stock Option
EARNINGS (LOSS) PER SHARE
Antidilutive securities not included in computation of diluted loss per share (in shares)	7.6	13.5	14.5
Warrant
EARNINGS (LOSS) PER SHARE
Antidilutive securities not included in computation of diluted loss per share (in shares)	4.9	4.9
Exercise price of warrants (in dollars per share)	$ 3.77	$ 3.77

MAJOR CUSTOMERS

12 Months Ended

Dec. 31, 2024

MAJOR CUSTOMERS

MAJOR CUSTOMERS

(19) MAJOR CUSTOMERS

The following customers contributed 10% or more of the Company’s revenue in at least one of the years ended December 31, 2024, 2023 and 2022:


	Year ended December 31,
	2024		2023		2022
Verizon Communications Inc.	14	%	11	%	15	%

At December 31, 2024 and 2023, no customer accounted for 10% or more of the Company’s accounts receivable balance. The Company performs ongoing credit evaluations of its customers and generally does not require collateral on accounts receivable. The Company maintains an allowance for doubtful accounts and such losses have historically been within management’s expectations.

ACCOUNTS RECEIVABLE, NET (Tables)

12 Months Ended

Dec. 31, 2024

ACCOUNTS RECEIVABLE, NET

Schedule of accounts receivable, net

Accounts receivable, net, consisted of the following (in thousands):


	December 31,
	2024		2023
Accounts receivable	$	256,174	$	269,933
Allowance for doubtful accounts		(1,456)		(1,512)
Accounts receivable, net	$	254,718	$	268,421

Schedule of allowance for doubtful accounts

The Company’s allowance for doubtful accounts activity was as follows (in thousands):


					Charges
	Balance at				(credits) to				Balance at
	beginning		Charges		other				end of
Year ended December 31,	of year		to expense		accounts		Write-offs		year
2024	$	1,512	$	152	$	(75)	$	(133)	$	1,456
2023	$	1,427	$	428	$	143	$	(486)	$	1,512
2022	$	1,270	$	100	$	159	$	(102)	$	1,427

EARNINGS (LOSS) PER SHARE (Tables)

12 Months Ended

Dec. 31, 2024

EARNINGS (LOSS) PER SHARE

Schedule of calculations of shares used to compute loss per share

The shares used to compute loss per share were as follows (in thousands):


	Year ended December 31,
	2024	2023	2022
Weighted average shares outstanding—basic	174,044	170,408	156,668
Potential dilutive common shares	—	—	—
Weighted average shares outstanding—diluted	174,044	170,408	156,668

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 87,770	$ 26,494
Restricted cash	2,709	136
Accounts receivable, net	254,718	268,421
Inventory	79,179	77,521
Other current assets	39,286	46,146
Total current assets	463,662	418,718
Property and equipment, net	60,364	41,820
Intangible assets, net	187,537	238,087
Goodwill	300,892	300,892
Deferred income taxes	88,982	69,761
Operating lease right-of-use assets	34,544	39,783
Other assets	26,573	35,092
Total assets	1,162,554	1,144,153
Current liabilities:
Current portion of term debt	6,125	35,102
Accounts payable	87,759	85,164
Accrued expenses and other	106,251	91,687
Operating lease liabilities	9,443	15,739
Deferred revenue	119,295	113,381
Total current liabilities	328,873	341,073
Long-term debt, net of current	330,726	197,482
Warrant liability	8,064	5,295
Preferred stock liability, $0.01 par value per share; 10,000,000 shares authorized, none issued and outstanding at December 31, 2024; 55,000 shares issued and outstanding at December 31, 2023 ($56,650 liquidation preference)		53,337
Operating lease liabilities, net of current	37,376	38,711
Deferred revenue, net of current	20,991	19,218
Deferred income taxes	5,941	5,616
Other long-term liabilities	25,962	30,658
Total liabilities	757,933	691,390
Commitments and contingencies (Note 26)
Stockholders' equity:
Common stock, $0.0001 par value per share; 240,000,000 shares authorized; 175,599,250 shares issued and outstanding at December 31, 2024; 172,083,667 shares issued and outstanding at December 31, 2023	18	17
Additional paid-in capital	1,970,708	1,958,909
Accumulated deficit	(1,574,185)	(1,519,950)
Accumulated other comprehensive income	8,080	13,787
Total stockholders' equity	404,621	452,763
Total liabilities and stockholders' equity	$ 1,162,554	$ 1,144,153

STOCK-BASED COMPENSATION PLANS (Tables)

12 Months Ended

Dec. 31, 2024

STOCK-BASED COMPENSATION PLANS

Schedule of activity related to unvested restricted stock units


		Weighted
		Average
		Grant Date
	Shares	Fair Value
Unvested balance at January 1, 2024	7,091,368	$	3.18
Granted	1,943,760	$	3.24
Vested	(4,653,037)	$	3.33
Forfeited	(384,983)	$	3.16
Unvested balance at December 31, 2024	3,997,108	$	3.04

Schedule of activity related to performance based stock units


		Weighted
		Average
		Grant Date
	Shares	Fair Value
Unvested balance at January 1, 2024	6,297,931	$	2.07
Granted	1,884,337	$	4.03
Vested	(298,586)	$	3.12
Forfeited	(4,277,790)	$	1.44
Unvested balance at December 31, 2024	3,605,892	$	3.75

Schedule of stock-based compensation expenses which are Included in consolidated statement of operations

The consolidated statements of operations included stock-based compensation for the years ended December 31, 2024, 2023 and 2022 as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Product cost of revenue	$	300	$	510	$	471
Service cost of revenue		1,325		2,147		2,157
Research and development		3,166		4,933		5,108
Sales and marketing		4,397		7,111		6,074
General and administrative		6,898		7,105		4,897
	$	16,086	$	21,806	$	18,707

PREFERRED STOCK AND WARRANTS - Warrant and Preferred Stock Liability (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Preferred stock liability
Issued		$ 58,600
Fair value adjustments	$ 8,091	$ 1,548
Call premium	(3.00%)	(3.00%)
Warrant liability
Issued		$ 58,600
Fair value change	$ 2,769	(201)
Preferred Stock
Preferred stock liability
Balance at beginning of year	53,337
Issued		47,854
Payable in-kind dividends	2,743	3,935
Fair value adjustments	5,605	1,548
Call premium (3%)	1,851
Redemption (June 25, 2024)	(63,536)
Balance at end of year		53,337
Warrant liability
Issued		47,854
Warrant
Preferred stock liability
Issued		5,496
Warrant liability
Balance at beginning of year	5,295
Issued		5,496
Fair value change	2,769	(201)
Balance at end of year	$ 8,064	$ 5,295

LEASES - Other Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 18,619	$ 19,021	$ 20,363
Operating cash flows from finance leases			13
Financing cash flows from finance leases			$ 595
Weighted average remaining lease term (years):
Operating leases	5 years 4 months 6 days	5 years 6 months
Weighted average discount rate:
Operating leases	7.73%	6.34%

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS - Plans with overfunded or underfunded or non-funded accumulated benefit obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
Aggregate fair value of plan assets	$ 14,486	$ 13,609	$ 14,629
Defined Benefit Plan, Underfunded or Non-funded Plan
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
Aggregate projected benefit obligation	11,997	10,811
Aggregate accumulated benefit obligation	9,586	8,547
Aggregate fair value of plan assets	2,779	2,638
Defined Benefit Plan, Overfunded Plan
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
Aggregate projected benefit obligation	10,140	9,958
Aggregate accumulated benefit obligation	8,160	7,958
Aggregate fair value of plan assets	$ 11,707	$ 10,971

- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References + Details

PROPERTY AND EQUIPMENT - Property and equipment by geographic area (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
PROPERTY AND EQUIPMENT
Property and equipment, net	$ 60,364	$ 41,820
Israel
PROPERTY AND EQUIPMENT
Property and equipment, net	27,657	8,309
United States
PROPERTY AND EQUIPMENT
Property and equipment, net	20,445	20,807
Asia/Pacific
PROPERTY AND EQUIPMENT
Property and equipment, net	7,941	8,314
Canada
PROPERTY AND EQUIPMENT
Property and equipment, net	3,071	3,175
Europe
PROPERTY AND EQUIPMENT
Property and equipment, net	1,034	957
Other
PROPERTY AND EQUIPMENT
Property and equipment, net	$ 216	$ 258

STOCK-BASED COMPENSATION PLANS

12 Months Ended

Dec. 31, 2024

STOCK-BASED COMPENSATION PLANS

STOCK-BASED COMPENSATION PLANS

(20) STOCK-BASED COMPENSATION PLANS

The Company grants stock-based compensation to employees, officers and non-employee directors, as well as consultants and advisors of the Company and its subsidiaries under its Amended and Restated 2019 Incentive Award Plan which provides for the award of stock options, stock appreciation rights, restricted stock awards (“RSAs”), performance-based stock awards, restricted stock units (“RSUs”), performance-based stock units (“PSUs”) and other stock- or cash-based awards.

Executive Equity Arrangements

Inducement Awards

In connection with his appointment as President and Chief Executive Officer of Ribbon on March 16, 2020, the Company awarded Bruce McClelland sign-on equity grants, comprised of RSUs and a PSU grant with both market and service conditions. The market conditions surrounding the PSUs granted were not met by the expiration date of September 1, 2024 and therefore, the associated shares have been cancelled.

Performance-Based Stock Grants

In addition to granting RSAs and RSUs to its executives and certain of its employees, the Company also grants PSUs to certain of its executives and certain other employees. Vesting periods for RSAs, RSUs, and PSUs granted range from one to three years. PSUs granted consist of 60% that have both performance and service conditions (the “Performance PSUs”) and 40% that have both market and service conditions (the “Market PSUs”). Each Performance PSU is comprised of three consecutive fiscal year performance periods beginning in the year of grant, with one-third of the Performance PSUs attributable to each fiscal year performance period. The Market PSUs have one three-year performance period, beginning January 1 in the year of grant and ending on December 31, three years thereafter. The number of shares of common stock underlying the PSUs that can be earned will not exceed 200% of the Performance or Market PSUs. Shares subject to PSUs that fail to be earned will be forfeited.

Restricted Stock Units

The activity related to the Company’s RSUs for the year ended December 31, 2024 was as follows:


		Weighted
		Average
		Grant Date
	Shares	Fair Value
Unvested balance at January 1, 2024	7,091,368	$	3.18
Granted	1,943,760	$	3.24
Vested	(4,653,037)	$	3.33
Forfeited	(384,983)	$	3.16
Unvested balance at December 31, 2024	3,997,108	$	3.04

The total grant date fair value of restricted stock underlying RSUs that vested was $15.5 million in the year ended December 31, 2024, $19.3 million in the year ended December 31, 2023 and $18.1 million in the year ended December 31, 2022.

Performance-Based Stock Units

The activity related to the Company’s PSUs for the year ended December 31, 2024 was as follows:


		Weighted
		Average
		Grant Date
	Shares	Fair Value
Unvested balance at January 1, 2024	6,297,931	$	2.07
Granted	1,884,337	$	4.03
Vested	(298,586)	$	3.12
Forfeited	(4,277,790)	$	1.44
Unvested balance at December 31, 2024	3,605,892	$	3.75

The total grant date fair value of restricted stock underlying PSUs that vested was $0.9 million in the year ended December 31, 2024, $2.6 million in the year ended December 31, 2023 and $0.9 million in the year ended December 31, 2022.

Stock-Based Compensation

The consolidated statements of operations included stock-based compensation for the years ended December 31, 2024, 2023 and 2022 as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Product cost of revenue	$	300	$	510	$	471
Service cost of revenue		1,325		2,147		2,157
Research and development		3,166		4,933		5,108
Sales and marketing		4,397		7,111		6,074
General and administrative		6,898		7,105		4,897
	$	16,086	$	21,806	$	18,707

At December 31, 2024, there was $14.1 million, net of expected forfeitures, of unrecognized stock-based compensation expense related to unvested RSUs and PSUs. This expense is expected to be recognized over a weighted average period of approximately 1.2 years. The Company issues authorized and unissued shares under its equity plans and at December 31, 2024, there were approximately 2.0 million total shares of common stock reserved for that purpose with 0.1 million of those shares authorized only for issuance of shares upon exercise of stock options.

INVENTORY

12 Months Ended

Dec. 31, 2024

INVENTORY

INVENTORY

(8) INVENTORY

Inventory consisted of the following (in thousands):


	December 31,		December 31,
	2024		2023
On-hand assemblies and finished goods inventories	$	95,366	$	93,077
Deferred cost of goods sold		2,430		3,269
		97,796		96,346
Less noncurrent portion (included in Other assets)		(18,617)		(18,825)
Current portion	$	79,179	$	77,521

PREFERRED STOCK AND WARRANTS - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands				12 Months Ended
	Jun. 25, 2024	Mar. 28, 2023	Aug. 12, 2022	Dec. 31, 2023	Dec. 31, 2022
PREFERRED STOCK AND WARRANTS
Offering expenses paid					$ 1,654
Series A Preferred Stock
PREFERRED STOCK AND WARRANTS
Dividends Payable in Kind Year One		9.25%
Dividends Payable in Kind Year Two		9.75%
Dividends Payable In Cash Thereafter		12.00%
Proceeds from issuance of preferred stock		$ 53,400
Offering expenses paid				$ 3,500
Preferred stock, redemption, percentage year one		103.00%
Preferred stock, redemption, percentage year two		102.00%
Series A Preferred Stock \| Beneficial Owner
PREFERRED STOCK AND WARRANTS
Proceeds from issuance of preferred stock		$ 10,000
Private Placement
PREFERRED STOCK AND WARRANTS
Offering expenses paid			$ 1,700
Preferred Stock
PREFERRED STOCK AND WARRANTS
Preferred Stock, redemption rate (in percent)	103.00%
Redeemed of Preferred Stock	$ 63,500
Preferred Stock \| Private Placement
PREFERRED STOCK AND WARRANTS
Stock issued in equity offering (in shares)		55,000
Share price (in dollars per share)		$ 970
Warrant \| Series A Preferred Stock
PREFERRED STOCK AND WARRANTS
Number of shares of common stock entitled from warrants (in shares)		4,900,000
Warrant \| Private Placement
PREFERRED STOCK AND WARRANTS
Share price (in dollars per share)		$ 3.77
Number of shares of common stock entitled from warrants (in shares)		4,858,090

DEBT - Long term debt (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Mar. 24, 2023
DEBT
Current portion of Term Debt	$ 6,125	$ 35,102
Long-term Debt, net of Current (Face Amount)	342,125	200,293
Original Issue Discount	(6,261)
Unamortized Debt Issuance Costs - Contra-Liability	(5,138)	(2,811)
Long-term Debt, net of Current	330,726	197,482
Total Face Amount of Borrowings	348,250	235,395
Other Assets	1,134	557
Long-Term Debt - Contra Liability	11,399	2,811
Total Unamortized Original Issue Discount and Debt Issuance Costs	12,533	3,368
2020 Credit Facility
DEBT
Remaining Borrowing Capacity	$ 35,000	$ 72,289
Term Loan
DEBT
Average Interest Rates:	10.60%	10.00%
Letters of Credit
DEBT
Letters of Credit Outstanding		$ 2,711
Average Interest Rates:		4.50%
Letters of Credit \| 2020 Credit Facility
DEBT
Average Interest Rates:			4.50%

SALE OF KANDY COMMUNICATIONS BUSINESS

12 Months Ended

Dec. 31, 2024

SALE OF KANDY COMMUNICATIONS BUSINESS

SALE OF KANDY COMMUNICATIONS BUSINESS

(4) SALE OF KANDY COMMUNICATIONS BUSINESS

The Company completed the Kandy Sale on December 1, 2020 (the “Kandy Sale Date”). As consideration, AVCT paid Ribbon $45.0 million, subject to certain adjustments, in the form of Debentures and AVCT Warrants (collectively the “AVCT Units”). The Company received 43,778 AVCT Units as sale consideration.

The Debentures bore interest at a rate of 10% per annum, which was added to the principal amount of the Debentures. The Debentures were subject to mandatory conversion if the AVCT stock price was at or above $6.00 per share for 40 trading days in any 60 consecutive trading day period, subject to the satisfaction of certain other conditions. As of February 19, 2021, the stock price had traded above $6.00 for 40 days within a 60 consecutive trading day period, and accordingly, on September 8, 2021 (the “Debenture Conversion Date”), upon the completion of customary regulatory filings by AVCT, the Debentures were converted into 13,700,421 shares of AVCT common stock (the “Debenture Shares”).

The AVCT Warrants were independent of the Debentures and entitled the Company to purchase 4,377,800 shares of AVCT common stock at an exercise price of $0.01 per share.

The Company calculated the fair value of the Debentures at each measurement date using a Lattice-based valuation approach, which utilizes a binomial tree to model the different paths the price of AVCT’s common stock might take over

the Debentures’ life by using assumptions regarding the stock price volatility and risk-free interest rate. The Company used the Black-Scholes valuation model for estimating the fair value of the AVCT Warrants at each measurement date. The fair value of the AVCT Warrants was affected by AVCT’s stock price as well as valuation assumptions, including the volatility of AVCT’s stock price, expected term of the option, risk-free interest rate and expected dividends. Both the Lattice and Black-Scholes valuation models are based on available market data, giving consideration to all of the rights and obligations of each instrument and precluding the use of “blockage” discounts or premiums in determining the fair value of a large block of financial instruments.

On August 29, 2022, the Company and AVCT entered into a settlement agreement which provided for, amongst other things, the cancellation of the Company’s investment in the Debenture Shares and the AVCT Warrants with an aggregate fair value of $2.6 million. Pursuant to the settlement agreement, the Company and AVCT also entered into a Wind Down Agreement, pursuant to which a Reseller Agreement between the parties, as previously amended, was terminated, and the Company was granted a non-exclusive perpetual license to use and modify certain intellectual property owned by AVCT comprising WebRTC gateway technology that is integrated with Ribbon’s SBCs and Application Servers. As consideration, the Company paid AVCT $2.5 million in cash, the Debenture Shares were redeemed and canceled, and the AVCT Warrants were terminated and canceled. The perpetual license granted by AVCT is classified as Intangible assets, net in the Company’s consolidated balance sheet as of December 31, 2024 and 2023 in the amount of $1.0 million and $2.4 million, respectively.

The Company had no investment in AVCT as of December 31, 2024 or 2023 due to the settlement agreement entered into on August 29, 2022. The Company recorded losses of $41.3 million in the year ended December 31, 2022, representing the change in the fair value of the AVCT Investment.

The results of the Kandy Communications Business are excluded from the Company’s consolidated results for all periods subsequent to the Kandy Sale Date.

INCOME TAXES - Components of provision (benefit) for income taxes from continuing operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Current:
Federal	$ 21,619	$ 9,927	$ (3,582)
State	3,313	2,790	2,573
Foreign	122	7,312	4,744
Total current	25,054	20,029	3,735
Deferred:
Federal	(13,822)	(10,417)	(10,333)
State	(2,266)	(1,059)	(4,045)
Foreign	(799)	2,280	(3,873)
Total deferred	(16,887)	(9,196)	(18,251)
Total	$ 8,167	$ 10,833	$ (14,516)

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES

12 Months Ended

Dec. 31, 2024

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES

(15) DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES

The Company is exposed to financial market risk related to foreign currency fluctuations and changes in interest rates. These exposures are actively monitored by management. To manage the volatility related to the exposure to changes in interest rates, the Company may enter into derivative financial instruments. Management’s objective has been to reduce, where it is deemed appropriate to do so, fluctuations in earnings and cash flows associated with changes in interest rates. Ribbon’s policies and practices are to use derivative financial instruments only to the extent necessary to manage exposures. Ribbon does not hold or issue derivative financial instruments for trading or speculative purposes.

The Company records derivatives on the balance sheet at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative, whether the Company has elected to designate a derivative in a hedging relationship and apply hedge accounting and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. Derivatives designated and qualifying as a hedge of the exposure to changes in the fair value of an asset, liability, or firm commitment attributable to a specific risk, such as interest rate risk, are considered fair value hedges. Derivatives designated and qualifying as a hedge of the exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Derivatives may also be designated as hedges of the foreign currency exposure of a net investment in a foreign operation. Hedge accounting generally provides for the matching of the timing of gain or loss recognition on the hedging instrument with the recognition of the changes in the fair value of the hedged asset or liability that are attributable to the hedged risk in a fair value hedge, or the earnings effect of the hedged forecasted transactions in a cash flow hedge. The Company may enter into derivative contracts that are intended to economically hedge certain of its risk even though hedge accounting does not apply or the Company elects not to apply hedge accounting.

Cash Flow Hedge of Interest Rate Risk

As of December 31, 2023, the 2020 Term Loan Facility had an outstanding balance of $235.4 million and the Revolving Credit Facility was undrawn. Borrowings under the 2020 Credit Facility had variable interest rates based on SOFR (see Note 14). As a result of exposure to interest rate movements, during March 2020, the Company entered into an interest rate swap arrangement, which effectively converted its $400 million term loan with its variable interest rate based upon one-month LIBOR to an aggregate fixed rate of 0.904%, plus a leverage-based margin as defined in the 2020 Credit Facility.

On July 22, 2022, the Company sold $30 million of the notional amount of its interest rate swap back to its counterparty for $1.5 million, reducing the notional amount of this swap to $370 million. On August 16, 2022, the Company sold another $30 million of the notional amount of its interest rate swap back to its counterparty for $1.6 million, reducing the notional amount to $340 million, which approximated the current level of our term loan debt then outstanding. The gain in accumulated other comprehensive (loss) income related to the $60 million notional amount sold of $3.1 million was being released into earnings on a straight line basis over the remaining term of the 2020 Credit Facility as a decrease to interest expense until it was refinanced on June 21, 2024, the amortization of which totaled $0.4 million and $0.9 million for the years ended December 31, 2024 and 2023, respectively. The remaining unamortized gain in accumulated other comprehensive (loss) income of approximately $0.5 million was written off to interest expense in conjunction with the refinancing of the 2020 Credit Facility on June 21, 2024. See Note 14 for a description of the refinancing.

On March 24, 2023, the Company received $9.4 million, consisting of $0.4 million of interest and $9.0 million for the sale of $170 million of its $340 million notional amount interest rate swap back to its counterparty, reducing the notional amount to $170 million. On March 27, 2023, the Company received $9.8 million, consisting of $0.4 million of interest and $9.4 million for the sale of the remaining $170 million of its interest rate swap back to its counterparty. The portion of the gain in accumulated other comprehensive (loss) income related to the term loan debt prepaid on the date of the final sale of our swap totaled $7.3 million and was released into earnings immediately as Other expense, net. The portion of the gain in accumulated other comprehensive (loss) income related to our remaining term loan debt balance was $12.0 million and was being released into earnings on a straight line basis over the remaining term of the 2020 Credit Facility as a decrease to interest expense until it was refinanced on June 21, 2024, the amortization of which totaled $3.0 million and $4.7 million for the years ended December 31, 2024 and 2023, respectively. The remaining

unamortized gain in accumulated other comprehensive (loss) income of $4.4 million was written off to interest expense in conjunction with the refinancing of the 2020 Credit Facility on June 21, 2024. See Note 14 for a description of the refinancing.

The Company’s objectives in using interest rate derivatives have been to add stability to interest expense and to manage its exposure to interest rate movements. To accomplish this objective, the Company has used an interest rate swap as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount.

The effective portion of changes in the fair value of designated derivatives that qualify as cash flow hedges is recorded in Accumulated other comprehensive income in the consolidated balance sheet and is subsequently reclassified into earnings in the period that the hedged forecasted transactions affect earnings. During the year ended December 31, 2023, such a derivative was used to hedge the variable cash flows associated with the outstanding borrowings under the 2020 Credit Facility and the Company accounted for this derivative as an effective hedge until the final portion of the swap was sold on March 27, 2023. Any ineffective portion of the change in the fair value of the derivative would have been recognized directly in earnings. However, there was no hedge ineffectiveness recorded over the life of the swap.

Amounts reported in Accumulated other comprehensive income related to the Company’s derivative were reclassified to interest expense as interest was accrued on the Company’s variable-rate debt. The impact of the Company’s derivative financial instrument on its consolidated statements of comprehensive loss for the years ended December 31, 2024 and 2023 was as follows, net of tax (in thousands):


	Year ended December 31,
	2024		2023
Gain (loss) recognized in other comprehensive income (loss) on swap, net of tax	$	—	$	(2,715)
Amount reclassified from accumulated other comprehensive income to other expense, net upon sale of swap, net of tax		—		(5,099)
Amount reclassified from accumulated other comprehensive income to interest expense		(6,019)		(7,300)
Unrealized gain (loss) on interest rate swap, net of reclassifications and amortization	$	(6,019)	$	(15,114)

The Company had no derivative assets or liabilities at December 31, 2024 or 2023.

COMMITMENTS AND CONTINGENCIES

12 Months Ended

Dec. 31, 2024

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES

(26) COMMITMENTS AND CONTINGENCIES

Contingencies

Liabilities for Royalty Payments to the IIA

Prior to the ECI Acquisition, ECI had received research and development grants from the IIA. The Company assumed ECI’s contract with the IIA, which requires the Company to pay royalties to the IIA on proceeds from the sale of products which the Israeli government has supported by way of research and development grants. The royalties for grants prior to 2017 were calculated at the rates of 1.3% to 5.0% of the aggregated proceeds from the sale of such products developed at certain of the Company’s R&D centers, up to an amount not exceeding 100% of such grants plus interest at LIBOR. Effective for grants approved in 2017 and effective through 2023, interest was calculated at the higher of LIBOR plus 1.5% to 2.75%. For grants approved in 2024 and thereafter, interest is calculated based on SOFR. At December 31, 2024, the Company had $1.5 million of unpaid royalties accrued. The Company’s maximum possible future royalties commitment at December 31, 2024 of $14.0 million, including interest of $0.8 million, was based upon estimates of future sales of products and services and the grants received from the IIA not yet repaid.

Litigation

The Company is often a party to disputes and legal proceedings that it considers routine and incidental to its business, including those described below. The Company believes that it has meritorious defenses to the allegations made in the pending cases and intends to vigorously defend these lawsuits; however, the Company is currently unable to forecast the ultimate outcome of these or similar matters. Since it is difficult to predict the outcome of legal proceedings, it is possible that the ultimate outcomes could materially and adversely affect the Company’s business, financial position, results of operations or cash flows. Accordingly, with respect to these proceedings, the Company is currently unable to reasonably estimate the possible loss or range of possible loss.

Miller Complaint. On November 8, 2018, Ron Miller, a purported stockholder of the Company, filed a Class Action Complaint (the “Miller Complaint”) in the United States District Court for the District of Massachusetts (the “Massachusetts District Court”) against the Company and three of its former officers (collectively, the “Defendants”), claiming to represent a class of purchasers of Sonus common stock during the period from January 8, 2015 through March 24, 2015 and alleging violations of the federal securities laws. Similar to a previous complaint entitled Sousa et al. vs. Sonus Networks, Inc. et al., which was dismissed with prejudice by an order dated June 6, 2017, the Miller Complaint claims that the Defendants made misleading forward-looking statements concerning Sonus’ expected fiscal first quarter of 2015 financial performance, which statements were also the subject of an August 7, 2018 Securities and Exchange Commission Cease and Desist Order, whose findings the Company neither admitted nor denied. The Miller plaintiffs were seeking monetary damages.

After the Miller Complaint was filed, several parties filed and briefed motions seeking to be selected by the Massachusetts District Court to serve as a Lead Plaintiff in the action. On June 21, 2019, the Massachusetts District Court appointed a group as Lead Plaintiffs and the Lead Plaintiffs filed an amended complaint on July 19, 2019. On August 30, 2019, the Defendants filed a motion to dismiss the Miller Complaint and, on October 4, 2019, the Lead Plaintiffs filed an opposition to the motion to dismiss. In June 2023, the Defendants agreed to a settlement in principle with the named plaintiffs, and final approval of the settlement was provided by the court on April 24, 2024. The settlement provided a release of all claims asserted in the litigation to all Defendants, who continue to deny liability. The

$4.5 million settlement amount was funded by the provider of the Company’s Directors and Officers liability insurance policy.

Charter Complaint. On September 19, 2022, Charter Communications Operating, LLC (“Charter”) filed two complaints against two of our subsidiaries (Sonus Networks, Inc. and Ribbon Communications Operating Company, Inc.) alleging breach of contract with respect to indemnification obligations purportedly owed to Charter in connection with Charter’s legal dispute with Sprint Communications Company L.P., which was settled by Charter in March 2022. One complaint was filed in the Supreme Court of the State of New York, in New York County; the second complaint was filed by Charter as well as co-plaintiffs Charter Communications Holding Company, LLC and Bright House Networks, LLC, in the Superior Court of the State of Delaware in and for New Castle County. In both complaints, Charter is seeking monetary damages. The Company filed its answer to the first complaint file in New York on December 7, 2022 and to the second complaint filed in Delaware on January 9, 2023. Discovery is on-going and the court in the Delaware complaint has set a trial date of June 2025. No trial date has been set for the case in New York.

WideOpenWest Complaint. On August 9, 2023, WideOpenWest, Inc. and WideOpenWest Finance, LLC (collectively, “WOW”) filed a complaint against Ribbon alleging breach of contract with respect to indemnification obligations purportedly owed to WOW in connection with WOW’s legal dispute with Sprint Communications Company L.P., which was settled by WOW in the second quarter of 2023. The complaint was filed in the 429th Judicial District of the District Court of the State of Texas, in Collin County, Texas and has since been transferred to the 493rd Judicial District Court in Collin County. In the complaint, WOW is seeking monetary damages. The Company filed its answer to the complaint on October 5, 2023. On October 14, 2024, the Company and WOW agreed to settle this matter. In connection with the settlement, the Company will pay WOW a total of $5.0 million, with $2.0 million paid at the time of settlement and the remaining $3.0 million paid over the next 18-months in equal quarterly installments.

STOCK-BASED COMPENSATION PLANS - Stock-Based Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Stock-based compensation
Stock-based compensation	$ 16,086	$ 21,806	$ 18,707
Product cost of revenue
Stock-based compensation
Stock-based compensation	300	510	471
Service cost of revenue
Stock-based compensation
Stock-based compensation	1,325	2,147	2,157
Research and development
Stock-based compensation
Stock-based compensation	3,166	4,933	5,108
Sales and marketing
Stock-based compensation
Stock-based compensation	4,397	7,111	6,074
General and administrative
Stock-based compensation
Stock-based compensation	$ 6,898	$ 7,105	$ 4,897

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Section 35
-Paragraph 1D
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-Subparagraph (f)(2)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(v)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ / shares in Units, $ in Thousands				12 Months Ended
	Mar. 28, 2023 USD ($) $ / shares shares	Aug. 12, 2022 USD ($) $ / shares shares	Sep. 08, 2021 shares	Dec. 31, 2024 USD ($) segment item $ / shares	Dec. 31, 2023 USD ($) $ / shares	Dec. 31, 2022 USD ($)	Aug. 29, 2022 USD ($)	Dec. 01, 2020 $ / shares shares
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Common stock, par value (in dollars per share) \| $ / shares				$ 0.0001	$ 0.0001
Offering expenses paid						$ 1,654
Number of operating segments \| segment				2
Maximum measurement period from the acquisition date within which company records adjustments to the assets acquired and liabilities assumed (in years)				1 year
Number of primary revenue sources \| item				2
Revenue agreement term				1 year
Total Face Amount of Borrowings				$ 348,250	$ 235,395
Fair value of debt				350,400	235,100
Warrants liabilities				8,064	5,295
Issued					58,600
Cumulative dividends on preferred stock					3,900
Foreign currency exchange losses				5,741	(44)	1,576
Advertising expense				1,700	1,200	1,500
Accrued expenses and other				5,200	5,400
Other long-term liabilities				7,100	6,800
Warranty				$ 12,300	12,243	11,857
Percent threshold (as a percent)				50.00%
Term loan facility \| 2020 credit facility
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Total Face Amount of Borrowings				$ 348,300	235,400
General and administrative
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Foreign currency exchange losses				$ 5,700	(100)	$ 1,600
Leasehold improvements
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Property and equipment, useful life (in years)				5 years
Software licenses
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Property and equipment, useful life (in years)				3 years
Minimum
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Revenue recognition, duration of training service				1 day
Contract with customer, payments term				30 days
Property and equipment, useful life (in years)				2 years
Standard product warranty period (in years)				1 year
Minimum \| Software licenses
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Property and equipment, useful life (in years)				2 years
Maximum
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Revenue recognition, duration of training service				5 days
Contract with customer, payments term				60 days
Property and equipment, useful life (in years)				5 years
Standard product warranty period (in years)				3 years
Maximum \| Software licenses
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Property and equipment, useful life (in years)				5 years
Disposal Group, Disposed of by Sale, Not Discontinued Operations
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Fair value of AVCT units				$ 0	0		$ 2,600
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Kandy Communications Business
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Number of shares of common stock entitled from warrants (in shares) \| shares								4,377,800
Exercise price of warrants (in dollars per share) \| $ / shares								$ 0.01
Debt conversion, converted instrument, shares issued (in shares) \| shares			13,700,421
Series A Preferred Stock
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Offering expenses paid					3,500
Private Placement
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Common stock, par value (in dollars per share) \| $ / shares		$ 0.0001
Sale of stock, number of shares issued in transaction (in shares) \| shares		17,071,311
Sale of stock (in dollars per share) \| $ / shares		$ 3.05
Sale of stock, consideration received on transaction		$ 52,100
Offering expenses paid		1,700
Private Placement \| Majority Shareholder
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Sale of stock, consideration received on transaction		$ 10,000
Preferred Stock
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Issued					47,854
Preferred Stock \| Private Placement
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Common stock issued in equity offering (in shares) \| shares	55,000
Share price (in dollars per share) \| $ / shares	$ 970
Warrant
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Issued					$ 5,496
Warrant \| Series A Preferred Stock
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Number of shares of common stock entitled from warrants (in shares) \| shares	4,900,000
Warrant \| Private Placement
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Share price (in dollars per share) \| $ / shares	$ 3.77
Number of shares of common stock entitled from warrants (in shares) \| shares	4,858,090
Warrant \| Private Placement \| Common stock
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Common stock, par value (in dollars per share) \| $ / shares	$ 0.0001
Exercise price of warrants (in dollars per share) \| $ / shares	$ 3.77
Warrant \| Private Placement \| Series A Preferred Stock
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Proceeds from issuance of common stock	$ 53,400
Warrant \| Private Placement \| Series A Preferred Stock \| Beneficial Owner
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Proceeds from issuance of common stock	$ 10,000

RELATED PARTIES (Details) - USD ($) $ in Thousands	12 Months Ended
RELATED PARTIES (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
RELATED PARTIES
Total revenue	$ 833,881	$ 826,339	$ 819,760
Accounts receivable from shareholder	254,718	268,421
Related party
RELATED PARTIES
Total revenue	11,300	12,800	$ 6,600
Accounts receivable from shareholder	$ 5,500	$ 3,900

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-41

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 270
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482964/270-10-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (ee)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 4: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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-Subparagraph (b)
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 924
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479941/924-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-5

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-URI https://asc.fasb.org/1943274/2147482810/280-10-50-30

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-42

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 22
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-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147482810/280-10-50-40

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Subparagraph (a)
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-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-4

+ Details

PREFERRED STOCK AND WARRANTS (Tables)

12 Months Ended

Dec. 31, 2024

PREFERRED STOCK AND WARRANTS

Schedule of fair value of preferred stock and warrants


	December 31,
	2024			2023
Stock price	$	4.16		$	2.90
Strike price	$	3.77		$	3.77
Risk-free rate		4.21	%		3.95	%
Volatility		57.5	%		60.5	%
Dividend yield		0.0	%		0.0	%
Time to expiration (years)		2.2			3.2
Fair value of Warrant per share	$	1.66		$	1.09

The changes in the Company’s Preferred Stock for the year ended December 31, 2024 and 2023 were as follows (in thousands):


	Year ended December 31,
	2024			2023
Balance at beginning of year	$	53,337	$	—
Issued		—		47,854
Payable in-kind dividends		2,743		3,935
Fair value adjustments		5,605		1,548
Call premium (3%)		1,851		—
Redemption (June 25, 2024)		(63,536)		—
Balance at end of year	$	—	$	53,337

The changes in the Company’s Warrant liabilities for the years ended December 31, 2024 and 2023 were as follows (in thousands):


	Year ended December 31,
	2024		2023
Balance at beginning of year	$	5,295	$	—
Issued		—		5,496
Fair value change		2,769		(201)
Balance at end of year	$	8,064	$	5,295

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS - Net periodic benefit costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
Service cost	$ 1,325	$ 1,193	$ 1,355
Interest cost	926	938	563
Expected return on plan assets	(592)	(607)	(266)
Settlement (credit) charge	(234)	(417)	808
Amortization of prior service cost	$ (320)	$ (320)	$ (320)
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent
Amortization of net (gain) loss	$ (150)	$ (165)	$ 275
Net periodic benefit costs	$ 955	$ 622	$ 2,415
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent

EMPLOYEE DEFINED CONTRIBUTION PLANS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
EMPLOYEE DEFINED CONTRIBUTION PLANS
Employees' contribution	50.00%
Employees' eligibility earnings	4.00%
Maximum eligible earnings	2.00%
Defined contribution expense	$ 3.0	$ 3.0	$ 3.3

NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS - Assumptions used to determine net period benefit cost (Details)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS
Discount rate	4.65%	4.74%	2.24%
Expected long-term return on plan assets	4.19%	4.34%	1.79%
Rate of compensation increase	4.08%	4.02%	3.90%
Interest crediting rate	1.25%	1.25%	1.25%

INCOME TAXES

12 Months Ended

Dec. 31, 2024

INCOME TAXES

INCOME TAXES

(24) INCOME TAXES

The components of loss from continuing operations before income taxes consisted of the following (in thousands):


	Year ended December 31,
	2024		2023		2022
Income (loss) before income taxes:
United States	$	22,685	$	(5,363)	$	(84,784)
Foreign		(68,753)		(50,010)		(27,815)
	$	(46,068)	$	(55,373)	$	(112,599)

The provision (benefit) for income taxes from continuing operations consisted of the following (in thousands):


	Year ended December 31,
	2024		2023		2022
Provision (benefit) for income taxes:
Current:
Federal	$	21,619	$	9,927	$	(3,582)
State		3,313		2,790		2,573
Foreign		122		7,312		4,744
Total current		25,054		20,029		3,735
Deferred:
Federal		(13,822)		(10,417)		(10,333)
State		(2,266)		(1,059)		(4,045)
Foreign		(799)		2,280		(3,873)
Total deferred		(16,887)		(9,196)		(18,251)
Total	$	8,167	$	10,833	$	(14,516)

A reconciliation of the Company’s effective tax rate for continuing operations to the U.S. statutory federal rate is as follows:


	Year ended December 31,
	2024		2023		2022
U.S. statutory income tax rate	21.0	%	21.0	%	21.0	%
State income taxes, net of federal benefit	(0.8)		(2.1)		1.8
Foreign income taxes	2.6		(9.9)		(1.4)
Stock-based compensation	(4.2)		(5.4)		(2.4)
Tax credits	2.2		7.7		2.2
Uncertain tax positions	15.2		2.0		1.3
Valuation allowance	(37.2)		(27.0)		(3.8)
Other permanent adjustments	(14.2)		(1.3)		(2.6)
Permanent foreign exchange adjustments	(3.9)		(2.3)		(1.4)
Other, net	1.5		(2.3)		(1.8)
Effective income tax rate	(17.8)	%	(19.6)	%	12.9	%

The following is a summary of the significant components of deferred income tax assets and liabilities (in thousands):


	December 31,
	2024		2023
Assets:
Net operating loss carryforwards	$	399,412	$	398,050
Capital loss carryforwards		100,069		100,061
Tax credit carryforwards		25,405		29,541
Capitalized research and development expenses		71,587		58,959
Deferred revenue		7,687		2,042
Accrued expenses		12,106		10,901
Inventory		1,899		4,108
Stock-based compensation		1,299		1,506
Fixed assets		624		159
Lease liabilities		11,993		12,009
Other temporary differences		1,551		440
		633,632		617,776
Valuation allowance		(493,855)		(488,799)
Total deferred tax assets		139,777		128,977
Liabilities:
Intangible assets		(37,488)		(45,448)
Operating lease right-of-use assets		(8,712)		(8,817)
Unremitted foreign income		(10,536)		(10,567)
Total deferred tax liabilities		(56,736)		(64,832)
Total net deferred tax assets	$	83,041	$	64,145

The deferred tax assets and liabilities based on tax jurisdictions are presented in the Company’s consolidated balance sheets as follows:


	December 31,
	2024		2023
Deferred income taxes - net noncurrent assets	$	88,982	$	69,761
Deferred income taxes - net noncurrent liabilities		(5,941)		(5,616)
	$	83,041	$	64,145

At December 31, 2024, the Company had U.S. federal net operating losses (“NOLs”) of $100.2 million. The Company also had U.S. state NOLs of $51.0 million. In addition, the Company had $1.6 billion of Israel NOLs. The U.S. federal NOL carryforwards expire between 2025 and 2037. The U.S. state NOLs begin to expire in 2025, and the Company also has indefinite-lived state NOLs. The Israel NOLs do not expire.

The Company also has available federal, state and foreign income tax credit carryforwards of $25.4 million. The federal foreign tax credit carryforwards expire between 2030 and 2032. The state tax credits, which are primarily research and development credits, begin to expire in 2025, while others can be carried forward until exhausted. The foreign income tax credits expire in various periods.

The Company has provided for income taxes on the undistributed earnings of its non-U.S. subsidiaries as of December 31, 2024, excluding Ireland and Israel. These subsidiaries, excluding Ireland and Israel, are cost-plus or limited risk distributors that are not anticipated to need to use excess funds locally. Accordingly, the Company is required to recognize and record deferred taxes in 2024. The deferred taxes, which are primarily future withholding taxes, are recorded on the entire outside basis differences related to the foreign subsidiaries, the largest of these differences being undistributed earnings. Undistributed profits of Ireland and Israel, as well as other outside basis differences in foreign subsidiaries, were indefinitely reinvested in foreign operations. Quantification of the deferred tax liability, if any, associated with indefinitely reinvested earnings and outside basis differences was not practicable.

Under the provisions of the Internal Revenue Code, the net operating losses and tax credit carryforwards are subject to review and possible adjustment by the Internal Revenue Service. Net operating losses and tax credit carryforwards may become subject to an annual limitation in the event of certain cumulative changes in the ownership of significant shareholders over a three-year period in excess of 50%, as defined under sections 382 and 383 of the Internal Revenue Code, as well as similar state provisions. As a result of the Sonus and GENBAND merger in 2017, the Company has $92.8 million of U.S. federal net operating loss carryforwards remaining as of December 31, 2024 with an annual section 382 limitation of $9.7 million. The Company believes these NOLs are fully realizable. As a result of the ECI Acquisition in 2020, the Company has $9.6 million of U.S. federal NOLs remaining as of December 31, 2024 with an annual section 382 limitation of $1.1 million. The Company does not believe all of these NOLs are realizable and, therefore, have recorded a partial valuation allowance against these NOLs.

The Company performed an analysis to determine if, based on all available evidence, it considered it more likely than not that some portion or all of the recorded deferred tax assets will not be realized in a future period. Accordingly, the Company has recorded a valuation allowance against its U.S. deferred tax assets of $18.6 million at December 31, 2024 and $23.4 million at December 31, 2023. The Company also maintains a valuation allowance against certain of its foreign deferred tax assets, predominantly Israel, amounting to approximately $475 million at December 31, 2024 and $465 million at December 31, 2023. The deferred tax assets recognized with no valuation allowance at December 31, 2024 and 2023 primarily relate to other foreign subsidiaries where recoverability is concluded to be more likely than not based on the Company’s cost-plus compensation policy, as well as NOLs and tax credits in the U.S. that are expected to be utilized prior to expiration.

A reconciliation of the Company’s unrecognized tax benefits is as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Unrecognized tax benefits at January 1	$	10,932	$	12,001	$	17,813
Increases related to current year tax positions		607		—		156
Increases related to prior period tax positions		53		52		40
Decreases related to the lapse of the applicable statute of limitations		(1,268)		(821)		(560)
Decreases related to prior period tax positions		(4,458)		(300)		(5,448)
Unrecognized tax benefits at December 31,	$	5,866	$	10,932	$	12,001

The Company accounts for interest and penalties related to uncertain tax positions as part of its provision for income taxes. The Company had $6.7 million, $14.0 million and $14.9 million of unrecognized tax benefits, including penalties and interest, at December 31, 2024, 2023 and 2022, respectively. Of these amounts, $3.6 million, $10.5 million and $11.2 million represent the amount of unrecognized tax benefits that, if recognized, would impact the effective income tax rate for the years ended December 31, 2024, 2023 and 2022, respectively. The Company recorded income tax expense (benefit) for potential penalties and interest of $(2.2) million, $0.2 million and $(0.3) million for the years ended December 31, 2024, 2023 and 2022, respectively. The Company had $0.9 million and $3.2 million accrued in Other long-term liabilities for penalties and interest at December 31, 2024 and 2023, respectively. The Company believes that it is reasonably possible that $0.4 million in tax positions related to its unrecognized tax benefits will be recognized within the next twelve months.

The Company and its subsidiaries file income tax returns in the U.S. federal jurisdiction as well as various state and foreign jurisdictions. Generally, the tax years 2021 through 2024 remain open to examination by the major taxing jurisdictions in which the Company operates. The Company’s federal and state NOLs generated prior to 2020 could be adjusted on examination even though the year in which the loss was generated is otherwise closed by the statute of limitations.

As of December 31, 2024, the Company had ongoing income tax audits in certain foreign countries. Management believes that an adequate provision has been recorded for any adjustments that may result from tax examinations.

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 2: http://www.xbrl.org/2003/role/exampleRef
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-Publisher FASB
-URI https://asc.fasb.org/740/tableOfContent

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-Paragraph 14
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-Paragraph 17
-Subparagraph (b)
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482603/740-30-50-2

+ Details

ACCRUED EXPENSES AND OTHER (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
ACCRUED EXPENSES AND OTHER
Employee compensation and related costs	$ 44,948	$ 33,682
Professional fees	16,339	19,702
Taxes payable	6,364	8,383
Other	38,600	29,920
Total accrued expenses	$ 106,251	$ 91,687

STOCK-BASED COMPENSATION PLANS - Narrative (Details) $ in Thousands, shares in Millions	12 Months Ended
	Dec. 31, 2024 USD ($) item shares	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Stock-based compensation
Fair value of vested restricted and performance-based stock grants	$ 14,822	$ 15,571	$ 9,858
Fair value of the assumed awards attributable to future stock-based compensation expense	$ 14,100
Expected period for unrecognized expense	1 year 2 months 12 days
Shares available for future issuance (in shares) \| shares	2.0
Performance Shares, Performance Based
Stock-based compensation
Granted percentage	60.00%
Number of performance periods \| item	3
Performance Shares, Market Based
Stock-based compensation
Performance period (in years)	3 years
Granted percentage	40.00%
Number of performance periods \| item	1
Percent of performance metrics achieved	200.00%
RSAs and RSUs
Stock-based compensation
Fair value of vested restricted and performance-based stock grants	$ 15,500	19,300	18,100
PSUs
Stock-based compensation
Fair value of vested restricted and performance-based stock grants	$ 900	$ 2,600	$ 900
Employee Stock Option
Stock-based compensation
Shares available for future issuance (in shares) \| shares	0.1
Minimum \| RSAs, RSUs and PSUs
Stock-based compensation
Performance period (in years)	1 year
Maximum \| RSAs, RSUs and PSUs
Stock-based compensation
Performance period (in years)	3 years

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

12 Months Ended

Dec. 31, 2024

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

(2) BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The consolidated financial statements have been prepared in United States dollars, in accordance with accounting principles generally accepted in the United States (“GAAP”).

Private Placement Offering

On March 28, 2023, the Company issued 55,000 shares of newly designated Series A Preferred Stock (the “Preferred Stock”) to investors in a private placement offering at a price of $970 per share, along with 4.9 million warrants (the “Warrants”) to purchase shares of the Company’s common stock, par value $0.0001 per share (the “Private Placement”), at the exercise price of $3.77 per share. The proceeds from the Private Placement were approximately $53.4 million, including approximately $10 million from existing related party stockholders (See Note 16).

Equity Offering

On August 12, 2022, the Company entered into a Securities Purchase Agreement with certain investors for the sale (the “Equity Offering”) in a private placement by the Company of 17,071,311 shares (the “Shares”) of the Company’s common stock, par value $0.0001 per share, at a price of $3.05 per share. The aggregate gross proceeds from the Equity Offering were approximately $52.1 million, including $10.0 million from existing related party shareholders, before deducting offering expenses paid by the Company of approximately $1.7 million.

The original issuance of the Shares in the Equity Offering was exempt from the registration requirements of the Securities Act of 1933, as amended (the “Securities Act”). The Company subsequently filed a registration statement on Form S-3 (the “Registration Statement”) with the SEC registering the Shares, which Registration Statement was declared effective by the SEC on September 23, 2022.

Operating Segments

The Company’s chief operating decision maker (the “CODM”) is its president and chief executive officer. The CODM assesses the Company’s performance based on the performance of two separate organizations within Ribbon: the Cloud and Edge segment (“Cloud and Edge”) and the IP Optical Networks segment (“IP Optical Networks”).

Significant Accounting Policies

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of Ribbon and its wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation.

Use of Estimates and Judgments

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and judgments relied upon in preparing these consolidated financial statements include accounting for business combinations, revenue recognition for arrangements that contain multiple performance obligations, inventory valuations, assumptions used to determine the fair value of stock-based compensation and the Preferred Stock and Warrants, intangible asset and goodwill valuations, including impairments, debentures and warrants, warranty accruals, legal contingencies and recoverability of Ribbon’s net deferred tax assets and the related valuation allowances. Ribbon regularly assesses these estimates and records changes in estimates in the period in which they become known. Ribbon bases its estimates on historical experience and various other assumptions that it believes to be reasonable under the circumstances. Actual results could differ from those estimates.

Reclassifications

Certain reclassifications, not affecting previously reported net income (loss), have been made to the previously issued financial statements to conform to the current year presentation.

Business Combinations

The Company recognizes identifiable assets acquired and liabilities assumed at their acquisition date fair values. Goodwill as of the acquisition date is measured as the excess of consideration transferred over the net of the acquisition date fair values of the assets acquired and the liabilities assumed and represents the expected future economic benefits arising from other assets acquired in the business combination that are not individually identified and separately recognized. While the Company uses its best estimates and assumptions as part of the purchase price allocation process to accurately value assets acquired and liabilities assumed at the acquisition date, its estimates are inherently uncertain and subject to refinement. As a result, during the measurement period, which may be up to one year from the acquisition date, the Company records adjustments to the assets acquired and liabilities assumed with the corresponding offset to goodwill to the extent that it identifies adjustments to the preliminary purchase price allocation. Upon the conclusion of the measurement period or final determination of the values of assets acquired and liabilities assumed, whichever comes first, any subsequent adjustments are recorded to the consolidated statements of operations.

Revenue Recognition

The Company derives revenue from two primary sources: products and services. Product revenue includes: 1) the Company’s proprietary hardware and software that function together to deliver the products’ essential functionality and 2) the Company’s software only solutions that can be used on either the Company’s hardware or third-party hardware. Both proprietary hardware and software only solutions are also sold on a standalone basis.

Services include customer support (software updates, upgrades and technical support), consulting, design services, installation services and training. Generally, contracts with customers contain multiple performance obligations, consisting of products and services. For these contracts, the Company accounts for individual performance obligations separately if they are considered distinct.

When an arrangement contains more than one performance obligation, the Company will allocate the transaction price to each performance obligation on a relative standalone selling price basis. The Company utilizes the observable price of goods and services, including when they are sold separately to similar customers, in order to estimate standalone selling price (“SSP”).

The Company’s software licenses typically provide a perpetual right to use the Company’s software. However, the Company also sells term-based software licenses that expire and Software-as-a-Service (“SaaS”)-based software which are referred to as subscription arrangements. The Company does not customize its software nor are installation services required, as the customer has a right to utilize internal resources or a third-party service company. The software and

hardware are delivered before related services are provided and are functional without professional services or customer support. The Company has concluded that its software licenses are functional intellectual property that are distinct, as the user can benefit from the software on its own.

Product revenue from sales of the Company’s perpetual and term-based software licenses is typically recognized when the software is made available for download, as this is the point the user of the software can direct the use of and obtain substantially all of the remaining benefits from the functional intellectual property. The Company begins to recognize software revenue related to the renewal of term-based software licenses at the start of the renewal period. Revenue related to sales of SaaS-based software is recognized ratably over the service period as the customer does not take possession of the software or have the ability to take possession of the software.

The Company offers warranties on its products. Certain of the Company’s warranties are considered to be assurance-type in nature, ensuring the product is functioning as intended. Assurance-type warranties do not represent separate performance obligations. The Company also sells separately-priced maintenance service contracts which qualify as service-type warranties and represent separate performance obligations. The Company does not allow and has no history of accepting product returns.

Service revenue includes revenue from customer support and other professional services. Customer support includes software updates on a when-and-if-available basis, telephone support, integrated web-based support and bug fixes or patches. The Company sells its customer support contracts at a percentage of list or net product price. Customer support revenue is recognized ratably over the term of the customer support agreement, which is typically one year.

The Company’s professional services include consulting, technical support, resident engineer services, design services and installation services. Because control transfers over time, revenue is recognized based on progress toward completion of the performance obligation. The method to measure progress toward completion requires judgment and is based on the nature of the products or services to be provided.

The Company generally uses the input method to measure progress for its contracts and to recognize revenue because it believes such method, in general, best depicts the transfer of assets to its customers. The input method measures costs the Company has incurred in the period for its contracts. In some infrequent instances, the Company may engage a third-party to perform services on its behalf and in those cases the output method is used to recognize revenue because it best depicts the transfer of assets to its customers. Under the output method, there is a cost-to-cost measure of progress. The progress toward completion is measured based on the ratio of costs incurred to date to the total estimated costs at completion of the performance obligation. When the measure of progress is based upon expended labor, progress toward completion is measured as the ratio of labor time expended to date versus the total estimated labor time required to complete the performance obligation. Revenue is recorded proportionally as costs are incurred or as labor is expended. Costs to fulfill these obligations can include internal labor as well as subcontractor costs.

Customer training includes courses offered by the Company. The related revenue is typically recognized as the training services are performed, typically over a period of one to five days.

Payment terms for the Company’s contracts with its customers typically range from 30 to 60 days from the invoice date. In certain cases, it may offer extended payment terms, which are assessed on a case-by-case basis.

The Company does not generally offer significant financing components in its contracts with customers. However, if a contract includes a significant financing component, the transaction price is adjusted for the time value of money. For the year ended December 31, 2024, the impact of financing components was immaterial.

Amounts billed to customers for sales and other taxes are excluded from the transaction price. Revenue is recognized net of any taxes collected from customers, which are subsequently remitted to government authorities.

Preferred Stock and Warrants

The Company accounted for the Preferred Stock until it was redeemed on June 25, 2024 and continues to account for the Warrants as liability-classified instruments based on an assessment of their specific terms in accordance with ASC Topic 480, Distinguishing Liabilities from Equity. The fair value option was elected for the Preferred Stock, as the Company considered fair value to best reflect the expected future economic value. These liabilities are remeasured to fair value at each reporting date using the same valuation methodology applied upon issuance using current input assumptions. The Preferred Stock was considered to be debt for our Consolidated Net Leverage Ratio covenant calculation required under our 2020 Credit Facility.

The value of the Preferred Stock was calculated using the Black-Derman-Toy (BDT) stochastic yield lattice model to capture the optimal timing of repayment, increasing dividend rate and other features, and the value of the Warrants is calculated using the Black-Scholes Pricing Model.

Changes in the fair value of the Preferred Stock and Warrants are reported as Other expense, net in the Company’s consolidated statements of operations.

Financial Instruments

The carrying amounts of the Company’s cash equivalents, accounts receivable, accounts payable and borrowings under a revolving credit facility in the Consolidated Balance Sheets approximates fair value due to the immediate or short-term nature of these financial instruments. Ribbon’s term debt balance as of December 31, 2024 and 2023 of $348.3 million and $235.4 million, respectively, had a fair value of approximately $350.4 million and $235.1 million, respectively. Our Warrants liabilities as of December 31, 2024 had a fair value of $8.1 million. Our Preferred Stock and Warrants liabilities as of December 31, 2023 had a combined fair value of $58.6 million, including cumulative dividends on the Preferred Stock of $3.9 million.

Financial instruments with remaining maturities or that are due within one year from the balance sheet date are classified as current. Financial instruments with maturities or that are payable more than one year from the balance sheet date are classified as noncurrent.

Fair Value Option - Investment in AVCT

The Company received debentures (the “Debentures”) and warrants (the “AVCT Warrants”) as sale consideration in connection with its December 1, 2020 sale of the Kandy Communications Business to American Virtual Cloud Technologies, Inc. (“AVCT”) (the “Kandy Sale”). On September 8, 2021 (the “Debenture Conversion Date”), the Debentures were converted into 13,700,421 shares of AVCT common stock (the “Debenture Shares”). In connection with the conversion of the Debentures to the Debenture Shares, the Company elected to use the fair value option to account for its equity investment in AVCT as permitted under Accounting Standards Codification (“ASC”) 825, Financial Instruments (“ASC 825”), which then refers to ASC 820, Fair Value Measurement (“ASC 820”) to provide the fair value framework for valuing such investments. In accordance with ASC 820, the Company recorded the investment in AVCT at fair value, with changes in fair value recorded as a component of Other (expense) income, net, in the consolidated statements of operations. See Note 4 for a discussion of the valuation of the Debentures, AVCT warrants and Debenture Shares.

Transfers of Financial Assets

The Company’s IP Optical Networks segment maintains customer receivables factoring agreements with a number of financial institutions. Under the terms of these agreements, the Company may transfer receivables to the financial institutions, on a non-recourse basis, provided that the financial institutions approve the receivables in advance. The

Company maintains credit insurance policies from major insurance providers or obtains letters of credit from the customers for a majority of its factored trade receivables. The Company accounts for the factoring of its financial assets as a sale of the assets and records the factoring fees, when incurred, as a component of interest expense in the consolidated statements of operations, and the proceeds from the sales of receivables are included in cash from operating activities in the consolidated statements of cash flows.

Factoring of accounts receivable and associated fees for the years ended December 31, 2024 and 2023 were as follows (in thousands):


	December 31,

	2024		2023
Accounts receivable sold	$	107,874	$	106,705
Less factoring fees		(2,228)		(2,736)
Net cash proceeds	$	105,646	$	103,969

Foreign Currency Translation

For foreign subsidiaries where the functional currency is the local currency, assets and liabilities are translated into U.S. dollars at the current exchange rate on the balance sheet date. Revenue and expenses are translated at average rates of exchange prevailing during each period. Translation adjustments for these subsidiaries are included in Accumulated other comprehensive income.

For foreign subsidiaries where the functional currency is the U.S. dollar, monetary assets and liabilities are translated into U.S. dollars at the current exchange rate on the balance sheet date. Nonmonetary assets and liabilities are remeasured into U.S. dollars at historical exchange rates. Revenue and expense items are translated at average rates of exchange prevailing during each period. Translation adjustments for these subsidiaries are included in Other expense, net.

Realized and unrealized foreign currency exchange gains and losses arising from transactions denominated in currencies other than the subsidiary’s functional currency are reflected in earnings.

The Company records its foreign currency (gains) losses as a component of Other expense, net. The Company recognized net foreign currency (gains) and losses of $5.7 million, less than $(0.1) million and $1.6 million for the years ended December 31, 2024, 2023 and 2022, respectively.

Inventory

Inventory is recorded at the lower of cost or market value using the first-in, first-out convention. The Company reduces the carrying value of inventory for those items that are potentially excess, obsolete or slow-moving based on changes in customer demand, technology developments or other economic factors.

Ribbon writes down evaluation equipment (equipment at customer sites for testing and evaluation) at the time of shipment to its customers, as it is probable that the inventory value will not be realized.

Deferred product costs represent deferred cost of revenue for product shipments to customers prior to satisfaction of Ribbon’s revenue recognition criteria. The Company classifies inventory that is not expected to be consumed within one year from the balance sheet date as noncurrent and includes such inventory as a component of Other assets.

Property and Equipment

Property and equipment are stated at cost, net of accumulated depreciation. Expenditures for maintenance and repairs are charged to expense as incurred. Depreciation is computed using the straight-line method over the estimated useful lives of the related assets, which range from two to five years. Leasehold improvements are amortized over the

lesser of the lease term or five years. When an asset is sold or retired, the cost and related accumulated depreciation or amortization are eliminated, and the resulting gain or loss, if any, is recognized in Loss from operations in the consolidated statement of operations. The Company reviews property and equipment for impairment in the same manner as intangible assets discussed below.

Software development costs associated with internal use software are incurred in three stages of development: the preliminary project stage, the application development stage and the post-implementation stage. Costs incurred during the preliminary project and post-implementation stages are expensed as incurred. Certain qualifying costs incurred during the application development stage are capitalized as property and equipment. Internal use software is amortized on a straight-line basis over its estimated useful life of three years, beginning when the software is ready for its intended use.

Intangible Assets and Goodwill

The Company’s intangible assets are comprised of in-process research and development, developed technology, customer relationships, trade names, and internal use software. Intangible assets are reviewed for impairment when events or changes in circumstances indicate that their carrying amounts may not be recoverable based upon the estimated undiscounted cash flows. Recoverability of intangible assets with estimated lives and other long-lived assets is measured by a comparison of the carrying amount of an asset or asset group to future net undiscounted cash flows expected to be generated by the asset or asset group. If these comparisons indicate that an asset is not recoverable, the Company will recognize an impairment loss for the amount by which the carrying value of the asset or asset group exceeds the related estimated fair value. Estimated fair value is based on either discounted future operating cash flows or appraised values, depending on the nature of the asset. The Company amortizes its intangible assets over their respective useful lives, with the exception of in-process research and development, which has an indefinite life until the product is generally available, at which time such asset is typically reclassified to developed technology, and the Company begins to amortize this asset. See Note 10 for additional information regarding the Company’s intangible assets.

Goodwill is recorded when the consideration for an acquisition exceeds the fair value of net tangible and identifiable intangible assets acquired. Goodwill is not amortized, but instead is tested for impairment at least annually, or more frequently if indicators of potential impairment exist, by comparing the fair value of the Company’s reporting unit to its carrying value.

The Company’s annual test for impairment of goodwill is completed as of October 1. For the purpose of testing goodwill for impairment, all goodwill is assigned to a reporting unit, which may either be an operating segment or a portion of an operating segment. The Company’s reporting units are its two operating segments, Cloud and Edge and IP Optical Networks. The Company performs a fair value analysis for each reporting unit using both an income and market approach, which encompasses a discounted cash flow analysis and a guideline public company analysis using selected multiples. The Company assesses each valuation methodology based upon the relevance and availability of the data at the time the valuation is performed and the methodologies are weighted appropriately. Any impairment charges are reported separately in the Company’s consolidated statements of operations.

Stock-Based Compensation

The Company’s stock-based compensation cost is measured at the grant date based on the fair value of the award and is recognized as expense over the requisite service period, which generally represents the vesting period, and includes an estimate of the awards that will be forfeited.

The Company uses the Black-Scholes valuation model for estimating the fair value of stock options on the grant date. The fair value of stock option awards is affected by the Company’s stock price as well as valuation assumptions, including the volatility of Ribbon’s stock price, expected term of the option, risk-free interest rate and expected dividends.

The Company may grant to certain of its executives and certain other employees performance-based stock units (“PSUs”) that include a market condition. The Company uses a Monte Carlo simulation approach to model future stock

price movements based upon the risk-free rate of return, the volatility of each entity and the pair-wise covariance between each entity. These results are then used to calculate the grant date fair values of the PSUs. The Company is required to record expense for the PSUs with market conditions through their respective final vesting dates regardless of the number of shares that are ultimately earned. Once the grant date criteria have been met for a fiscal year performance period, the Company records stock-based compensation expense based on its assessment of the probability that the respective performance condition will be achieved and the level, if any, of such achievement. The Compensation Committee determines the number of shares earned, if any, after the Company’s financial results for each fiscal year performance period are finalized. Upon the determination by the Compensation Committee of the number of shares that will be received upon vesting, such number of shares becomes fixed and the unamortized expense is recorded through the remainder of the service period, at which time any Performance PSUs earned will vest pending each employee’s continuing employment with Ribbon through that date.

Concentration of Risk

Ribbon is subject to counterparty risk as well as financial instrument concentration risk involving cash, cash equivalents and accounts receivable. To mitigate these risks, cash and cash equivalents are diversified and maintained with various financial institutions globally. In certain instances, advance payments, credit insurance, or customer issued letters of credit are required to mitigate potential risk.

Certain components and software licenses from third parties used in Ribbon’s products are procured from single sources of supply. The failure of a supplier, including a subcontractor, to deliver on schedule could delay or interrupt Ribbon’s delivery of products and thereby materially adversely affect Ribbon’s revenue and operating results.

Advertising Costs

Advertising costs are expensed as incurred and included as a component of Sales and marketing expense in the Company’s consolidated statements of operations. Advertising expenses were $1.7 million, $1.2 million and $1.5 million for the years ended December 31, 2024, 2023 and 2022, respectively.

Loss Contingencies and Reserves

Ribbon is subject to ongoing business risks arising in the ordinary course of business, including legal claims, that affect the estimation process of the carrying value of assets, the recording of liabilities and the possibility of various loss contingencies. An estimated loss contingency is accrued when it is probable that a liability has been incurred or an asset has been impaired and the amount of loss can be reasonably estimated. Ribbon regularly evaluates current information available to determine whether such amounts should be adjusted and records changes in estimates in the period they become known.

An allowance for doubtful accounts is estimated based on the Company’s assessment of the collectability of specific customer accounts.

Ribbon accrues for royalties for technology that it licenses from vendors based on established royalty rates and usage. Ribbon is periodically contacted by third parties who claim that Ribbon’s products infringe on certain intellectual property of a third party. Ribbon evaluates these claims and accrues amounts when it is probable that the obligation has been incurred and the amounts are reasonably estimable.

Warranty

The Company records warranty liabilities for estimated costs of fulfilling its obligations under standard limited hardware and software warranties at the time of sale. The specific warranty terms and conditions vary depending upon the country in which the Company does business, but generally includes material costs, technical support, labor and associated overhead over a period ranging from one to three years. At December 31, 2024, the Company’s liability for product warranties was $12.3 million of which $5.2 million was current and included in Accrued expenses and other and $7.1 million was long-term and included in Other long-term liabilities in the Company’s consolidated balance sheet. At

December 31, 2023, the Company’s liability for product warranties was $12.2 million, of which $5.4 million was current and included in Accrued expenses and other, and $6.8 million was long-term and included in Other long-term liabilities in the Company’s consolidated balance sheet.

Research and Development Grants

The Company records grants received from the Office of the Innovation Authority of the Israeli Ministry of Economics (the “IIA”) as a reduction to Research and development expense. Royalties payable to the IIA are recognized pursuant to sales of related products and services and are included in Cost of revenue (see Note 26).

Accounting for Leases

The Company accounts for its leases in accordance with Accounting Standards Codification (“ASC”) 842, Leases (“ASC 842”) (see Note 21). The Company has operating leases for corporate offices, and research and development facilities. Operating leases are reported separately in the Company’s consolidated balance sheets at December 31, 2024 and 2023. The Company has no finance leases as of December 31, 2024 or 2023.

Lease expense for minimum fixed lease payments is recognized on a straight-line basis over the lease term. The expense for finance leases would include both interest and amortization expense components, with the interest component calculated based on the effective interest method and the amortization component calculated based on straight-line amortization of the right-of-use asset over the lease term. Lease contracts may contain variable lease costs, such as common area maintenance, utilities and tax reimbursements that vary over the term of the contract. Variable lease costs are not included in minimum fixed lease payments and as a result, are excluded from the measurement of the right-of-use assets and lease liabilities. The Company expenses all variable lease costs as incurred.

Accounting for Income Taxes

Deferred tax assets and liabilities are recognized for the expected future consequences of events that have been reflected in the consolidated financial statements. Deferred tax assets and liabilities are determined based on the differences between the financial reporting and tax basis of assets and liabilities and operating loss carryforwards, using tax rates expected to be in effect for the years in which the differences are expected to reverse. The Company records valuation allowances to reduce deferred income tax assets to the amount that is more likely than not to be realized.

The Company has provided for income taxes on the undistributed earnings of its non-U.S. subsidiaries as of December 31, 2024, excluding Ireland and Israel, which are indefinitely reinvested. Accordingly, the Company is required to recognize and record deferred taxes for 2024 on the entire outside basis differences related to the foreign subsidiaries, the largest of these differences being undistributed earnings.

The Company determines whether it is more likely than not that a tax position will be sustained upon examination. If it is not more likely than not that a position will be sustained, no amount of the benefit attributable to the position is recognized. The tax benefit to be recognized of any tax position that meets the more likely than not recognition threshold is calculated as the largest amount that is more than 50% likely of being realized upon resolution of the contingency. The Company accounts for interest and penalties related to uncertain tax positions as part of its provision for income taxes.

Defined Benefit Plans

The Company has defined benefit plans for some of its employees at various international locations. The Company recognizes retirement benefit assets or liabilities in the consolidated balance sheets reflecting the funded status of pension and other retirement benefit plans. Retirement benefit assets and liabilities are adjusted for the difference between the benefit obligations and the plan assets at fair value (measured at year-end), with the offset recorded directly to stockholders’ equity through Other comprehensive income (loss), net of tax. The amount recorded in stockholders’ equity represents the after-tax unamortized actuarial gains or losses, unamortized transition obligations and unamortized prior service costs.

Recent Accounting Pronouncements

In November 2024, the Financial Accounting Standards Board (the "FASB") issued ASU 2024-03, Income Statement, Reporting Comprehensive Income: Expense Disaggregation Disclosures (Subtopic 220-40) (“ASU 2024-03”), which requires disaggregation of certain expense captions into specified categories in disclosures within the footnotes to the financial statements. The objective of this standard is to provide investors with information to better understand a public entity’s performance and prospects for future cash flows, and to compare their performance over time with that of other entities. ASU 2024-03 will be effective for the Company beginning with our 2027 annual financial statements and interim financial statements thereafter, with early adoption permitted. The adoption of ASU 2024-03 will require the Company to provide new footnote disclosure about the types of expenses that are included in certain captions on its Statements of Operations, such as Cost of revenue, Research and development, Sales and marketing, and General and administrative.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”), which increases the disclosure requirements around rate reconciliation information and certain types of income taxes companies are required to pay. ASU 2023-09 will be effective for the Company beginning with its 2025 annual financial statements, with early adoption permitted. We expect the adoption of the standard will require certain additional income tax disclosure.

In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures (“ASU 2023-07”), which improves reportable segment disclosure requirements, including enhancement of the disclosures of significant segment expenses and interim disclosure requirements, to enable investors to better understand an entity’s overall performance and assess potential future cash flows. ASU 2023-07 became effective for the Company beginning with this Annual Report on Form 10-K which includes the required additional segment disclosures.

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Narrative (Details) - USD ($) $ in Thousands						1 Months Ended	12 Months Ended
	Jun. 21, 2024	Mar. 27, 2023	Mar. 24, 2023	Aug. 16, 2022	Jul. 22, 2022	Aug. 16, 2022	Dec. 31, 2024	Dec. 31, 2023	Mar. 31, 2020
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Debt balance							$ 348,250	$ 235,395
Interest Expense
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Amount reclassified from accumulated other comprehensive income (loss)							6,019	7,300
Interest Rate Swap
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Derivative instrument sold		$ 170,000	$ 170,000	$ 30,000	$ 30,000	$ 60,000
Proceeds from sale		9,800	9,400	1,600	1,500
Notional amount			170,000	$ 340,000	$ 370,000	340,000
Amount reclassified from accumulated other comprehensive income (loss)		7,300				$ 3,100
Amortization of derivative instrument							400	900
Proceeds from derivative interest		400	400
Proceeds from sale of derivative, gross		9,400	$ 9,000
Interest Rate Swap \| Interest Expense
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Amount reclassified from accumulated other comprehensive income (loss)	$ 500
Interest Rate Swap \| Fair Value, Inputs, Level 2
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Interest rate derivative							0	0
2020 credit facility \| Interest Rate Swap
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Amount reclassified from accumulated other comprehensive income (loss)		$ 12,000
Amortization of derivative instrument							3,000	4,700
2020 credit facility \| Interest Rate Swap \| Interest Expense
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Amount reclassified from accumulated other comprehensive income (loss)	$ 4,400
Term loan facility \| 2020 credit facility
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Debt balance							$ 348,300	$ 235,400
Principal amount									$ 400,000
Fixed rate								0.904%

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenue:
Total revenue	$ 833,881	$ 826,339	$ 819,760
Cost of revenue:
Total cost of revenue	394,369	418,256	418,824
Gross profit	439,512	408,083	400,936
Operating expenses:
Research and development	179,941	190,660	203,676
Sales and marketing	137,830	137,460	147,766
General and administrative	68,740	54,962	51,053
Amortization of acquired intangible assets	25,969	28,601	29,646
Acquisition-, disposal- and integration-related		4,476	6,286
Restructuring and related	10,160	16,209	10,833
Total operating expenses	422,640	432,368	449,260
Income (loss) from operations	16,872	(24,285)	(48,324)
Interest expense, net	(33,821)	(27,320)	(19,780)
Other expense, net	(29,119)	(3,768)	(44,495)
Loss before income taxes	(46,068)	(55,373)	(112,599)
Income tax (provision) benefit	(8,167)	(10,833)	14,516
Net loss	$ (54,235)	$ (66,206)	$ (98,083)
Loss per share:
Basic (in dollars per share)	$ (0.31)	$ (0.39)	$ (0.63)
Diluted (in dollars per share)	$ (0.31)	$ (0.39)	$ (0.63)
Weighted average shares used to compute loss per share:
Basic (in shares)	174,044	170,408	156,668
Diluted (in shares)	174,044	170,408	156,668
Product
Revenue:
Total revenue	$ 447,229	$ 445,150	$ 442,680
Cost of revenue:
Cost of revenue	228,527	250,609	245,145
Service
Revenue:
Total revenue	386,652	381,189	377,080
Cost of revenue:
Cost of revenue	140,949	139,357	142,137
Amortization of acquired technology
Cost of revenue:
Amortization of acquired technology	$ 24,893	$ 28,290	$ 31,542

BUSINESS ACQUISITIONS (Tables)

12 Months Ended

Dec. 31, 2024

BUSINESS ACQUISITIONS

Schedule of components of acquisition related costs

The components of Acquisition-, disposal- and integration-related expenses incurred in the years ended December 31, 2024, 2023 and 2022 were as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Professional and services fees (disposal-related)	$	—	$	—	$	414
Integration-related expenses		—		4,476		5,872
	$	—	$	4,476	$	6,286

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)

12 Months Ended

Dec. 31, 2024

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The consolidated financial statements have been prepared in United States dollars, in accordance with accounting principles generally accepted in the United States (“GAAP”).

Private Placement Offering

Equity Offering

Operating Segments

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of Ribbon and its wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation.

Use of Estimates and Judgments

Reclassifications

Certain reclassifications, not affecting previously reported net income (loss), have been made to the previously issued financial statements to conform to the current year presentation.

Business Combinations

Revenue Recognition

Customer training includes courses offered by the Company. The related revenue is typically recognized as the training services are performed, typically over a period of one to five days.

Preferred Stock and Warrants

Changes in the fair value of the Preferred Stock and Warrants are reported as Other expense, net in the Company’s consolidated statements of operations.

Financial Instruments

Fair Value Option - Investment in AVCT

Transfers of Financial Assets

Factoring of accounts receivable and associated fees for the years ended December 31, 2024 and 2023 were as follows (in thousands):


	December 31,

	2024		2023
Accounts receivable sold	$	107,874	$	106,705
Less factoring fees		(2,228)		(2,736)
Net cash proceeds	$	105,646	$	103,969

Foreign Currency Translation

Realized and unrealized foreign currency exchange gains and losses arising from transactions denominated in currencies other than the subsidiary’s functional currency are reflected in earnings.

Inventory

Property and Equipment

Intangible Assets and Goodwill

Stock-Based Compensation

Concentration of Risk

Advertising Costs

Loss Contingencies and Reserves

An allowance for doubtful accounts is estimated based on the Company’s assessment of the collectability of specific customer accounts.

Warranty

Research and Development Grants

Accounting for Leases

Accounting for Income Taxes

Defined Benefit Plans

Recent Accounting Pronouncements

LEASES - Right of Use Lease Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Assets:
Operating lease assets	$ 34,544	$ 39,783
Liabilities:
Current Operating	9,443	15,739
Non-Current Operating	37,376	38,711
Total Operating lease liabilities	$ 46,819	$ 54,450

RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES (Tables)

12 Months Ended

Dec. 31, 2024

RESTRUCTURING AND FACILITIES CONSOLIDATION INITIATIVES

Schedule of restructuring accrual activity

The components of restructuring and related expense for the years ended December 31, 2024, 2023 and 2022 were as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Severance and related costs	$	4,036	$	9,875	$	5,230
Variable and other facilities-related costs		6,124		5,326		3,992
Accelerated amortization of lease assets due to cease-use		—		1,008		1,611
	$	10,160	$	16,209	$	10,833

A summary of the 2023 Restructuring Plan accrual activity for the years ended December 31, 2024 and 2023 were as follows (in thousands):


	Balance at		Initiatives				Balance at
	January 1,		charged to		Cash		December 31,
	2024		expense		payments		2024
Severance	$	671	$	2,003	$	(2,589)	$	85


	Balance at		Initiatives				Balance at
	January 1,		charged to		Cash		December 31,
	2023		expense		payments		2023
Severance	$	—	$	9,875	$	(9,204)	$	671

A summary of the 2022 Restructuring Plan accrual activity for the years ended December 31, 2024 and 2023 were as follows (in thousands):


	Balance at		Initiatives				Balance at
	January 1,		charged to		Cash		December 31,
	2024		expense		payments		2024
Variable and other facilities-related costs	$	468	$	6,123	$	(6,244)	$	347


	Balance at		Initiatives				Net transfer to		Balance at
	January 1,		charged to		Cash		operating lease		December 31,
	2023		expense		payments		accounts		2023
Severance	$	1,164	$	—	$	(1,164)	$	—	$	—
Variable and other facilities-related costs		890		5,326		(5,748)		—		468
Accelerated amortization of lease assets due to cease-use		—		1,008		—		(1,008)		—
	$	2,054	$	6,334	$	(6,912)	$	(1,008)	$	468

PREFERRED STOCK AND WARRANTS - Key Inputs (Details) - Level 3 - Black Scholes Pricing Model - Warrant	Dec. 31, 2024 $ / shares	Dec. 31, 2023 $ / shares
PREFERRED STOCK AND WARRANTS
Time to expiration (years)	2 years 2 months 12 days	3 years 2 months 12 days
Fair value of Warrant per share	$ 1.66	$ 1.09
Stock price
PREFERRED STOCK AND WARRANTS
Measurement Input	4.16	2.9
Strike price
PREFERRED STOCK AND WARRANTS
Measurement Input	3.77	3.77
Risk-free rate
PREFERRED STOCK AND WARRANTS
Measurement Input	0.0421	0.0395
Volatility
PREFERRED STOCK AND WARRANTS
Measurement Input	0.575	0.605
Dividend yield
PREFERRED STOCK AND WARRANTS
Measurement Input	0	0

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Rule 10b5-1 Arrangement Modified	false
Non-Rule 10b5-1 Arrangement Modified	false

INTANGIBLE ASSETS AND GOODWILL - Schedule of Components of Goodwill (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Oct. 01, 2024	Dec. 31, 2023
INTANGIBLE ASSETS AND GOODWILL
Goodwill	$ 584,298
Accumulated impairment losses	(283,406)
Goodwill, total	300,892		$ 300,892
Cloud and Edge
INTANGIBLE ASSETS AND GOODWILL
Goodwill	392,302
Accumulated impairment losses	(167,406)
Goodwill, total	224,896
IP Optical Networks
INTANGIBLE ASSETS AND GOODWILL
Goodwill	191,996
Accumulated impairment losses	(116,000)
Goodwill, total	$ 75,996	$ 76,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 24
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482548/350-20-55-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482573/350-20-50-1A

+ Details

REVENUE RECOGNITION - Schedule of Disaggregation of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
REVENUE RECOGNITION
Total revenue	$ 833,881	$ 826,339	$ 819,760
United States
REVENUE RECOGNITION
Total revenue	395,984	344,415	352,663
Europe, Middle East and Africa
REVENUE RECOGNITION
Total revenue	234,679	261,901	252,781
Asia/Pacific
REVENUE RECOGNITION
Total revenue	151,570	167,083	151,099
Other
REVENUE RECOGNITION
Total revenue	51,648	52,940	63,217
Product revenue
REVENUE RECOGNITION
Total revenue	447,229	445,150	442,680
Product revenue \| Cloud and Edge
REVENUE RECOGNITION
Total revenue	211,001	184,730	215,770
Product revenue \| IP Optical Networks
REVENUE RECOGNITION
Total revenue	236,228	260,420	226,910
Product revenue \| Sales to enterprise customers
REVENUE RECOGNITION
Total revenue	176,064	143,853	125,664
Product revenue \| Sales to service provider customers
REVENUE RECOGNITION
Total revenue	271,165	301,297	317,016
Product revenue \| Indirect sales through channel partner program
REVENUE RECOGNITION
Total revenue	170,426	157,495	131,998
Product revenue \| Direct sales
REVENUE RECOGNITION
Total revenue	276,803	287,655	310,682
Product revenue \| United States
REVENUE RECOGNITION
Total revenue	201,340	161,945	175,189
Product revenue \| Europe, Middle East and Africa
REVENUE RECOGNITION
Total revenue	129,824	151,938	147,523
Product revenue \| Asia/Pacific
REVENUE RECOGNITION
Total revenue	100,766	115,923	95,828
Product revenue \| Other
REVENUE RECOGNITION
Total revenue	15,299	15,344	24,140
Service
REVENUE RECOGNITION
Total revenue	386,652	381,189	377,080
Service revenue (maintenance)
REVENUE RECOGNITION
Total revenue	274,582	279,652	282,095
Service revenue (maintenance) \| Cloud and Edge
REVENUE RECOGNITION
Total revenue	212,988	219,939	222,238
Service revenue (maintenance) \| IP Optical Networks
REVENUE RECOGNITION
Total revenue	61,594	59,713	59,857
Service revenue (maintenance) \| United States
REVENUE RECOGNITION
Total revenue	133,182	133,737	132,655
Service revenue (maintenance) \| Europe, Middle East and Africa
REVENUE RECOGNITION
Total revenue	71,856	75,478	75,948
Service revenue (maintenance) \| Asia/Pacific
REVENUE RECOGNITION
Total revenue	39,863	39,891	41,677
Service revenue (maintenance) \| Other
REVENUE RECOGNITION
Total revenue	29,681	30,546	31,815
Service revenue (professional services)
REVENUE RECOGNITION
Total revenue	112,070	101,537	94,985
Service revenue (professional services) \| Cloud and Edge
REVENUE RECOGNITION
Total revenue	81,168	72,979	70,130
Service revenue (professional services) \| IP Optical Networks
REVENUE RECOGNITION
Total revenue	30,902	28,558	24,855
Service revenue (professional services) \| United States
REVENUE RECOGNITION
Total revenue	61,462	48,733	44,819
Service revenue (professional services) \| Europe, Middle East and Africa
REVENUE RECOGNITION
Total revenue	32,999	34,485	29,310
Service revenue (professional services) \| Asia/Pacific
REVENUE RECOGNITION
Total revenue	10,941	11,269	13,594
Service revenue (professional services) \| Other
REVENUE RECOGNITION
Total revenue	$ 6,668	$ 7,050	$ 7,262

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Dec. 31, 2024
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

REVENUE RECOGNITION (Tables)

12 Months Ended

Dec. 31, 2024

REVENUE RECOGNITION

Schedule of timing of performance obligation


	When Performance Obligation is Typically
Performance Obligation	Satisfied	When Payment is Typically Due
Software and Product Revenue
Software licenses (perpetual or term)	For perpetual licenses, typically when made available for download (point in time); for term-based licenses, at the beginning of the specified term (point in time)	Generally, within 30-60 days of invoicing, except for term licenses which may be paid for over time
Software licenses (subscription)	Upon activation of hosted site (over time)	Generally, within 30-60 days of invoicing
Hardware	When control of the hardware passes to the customer; typically, upon delivery (point in time)	Generally, within 30-60 days of invoicing
Software upgrades	Upon transfer of control; typically, when made available for download (point in time)	Generally, within 30-60 days of invoicing
Customer Support Revenue
Customer support	Ratably over the course of the support contract (over time)	Generally, within 30-60 days of invoicing
Professional Services
Other professional services (excluding training services)	As work is performed (over time), typically on the input method based on hours incurred	Generally, within 30-60 days of invoicing (upon completion of services)
Training	As the training is delivered (over time), typically one to five days	Generally, within 30-60 days of services being performed

Schedule of disaggregation of revenue


					Service
			Service		revenue
	Product		revenue		(professional
Year ended December 31, 2024	revenue		(maintenance)		services)		Total revenue
United States	$	201,340	$	133,182	$	61,462	$	395,984
Europe, Middle East and Africa		129,824		71,856		32,999		234,679
Asia Pacific		100,766		39,863		10,941		151,570
Other		15,299		29,681		6,668		51,648
	$	447,229	$	274,582	$	112,070	$	833,881


					Service
			Service		revenue
	Product		revenue		(professional
Year ended December 31, 2023	revenue		(maintenance)		services)		Total revenue
United States	$	161,945	$	133,737	$	48,733	$	344,415
Europe, Middle East and Africa		151,938		75,478		34,485		261,901
Asia Pacific		115,923		39,891		11,269		167,083
Other		15,344		30,546		7,050		52,940
	$	445,150	$	279,652	$	101,537	$	826,339


					Service
			Service		revenue
	Product		revenue		(professional
Year ended December 31, 2022	revenue		(maintenance)		services)		Total revenue
United States	$	175,189	$	132,655	$	44,819	$	352,663
Europe, Middle East and Africa		147,523		75,948		29,310		252,781
Asia Pacific		95,828		41,677		13,594		151,099
Other		24,140		31,815		7,262		63,217
	$	442,680	$	282,095	$	94,985	$	819,760


	Year ended December 31,
	2024		2023		2022
Indirect sales through channel partner program	$	170,426	$	157,495	$	131,998
Direct sales		276,803		287,655		310,682
	$	447,229	$	445,150	$	442,680

The Company’s product revenue from sales to enterprise customers and from sales to service provider customers for the years ended December 31, 2024, 2023 and 2022 was as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Sales to enterprise customers	$	176,064	$	143,853	$	125,664
Sales to service provider customers		271,165		301,297		317,016
	$	447,229	$	445,150	$	442,680

The Company’s product revenue and service revenue components by segment for the years ended December 31, 2024, 2023 and 2022 was as follows (in thousands):


	Year ended December 31,
	2024	2023	2022
Product revenue:
Cloud and Edge	211,001	184,730	215,770
IP Optical Networks	236,228	260,420	226,910
Total product revenue	447,229	445,150	442,680

Service revenue:
Maintenance:
Cloud and Edge	212,988	219,939	222,238
IP Optical Networks	61,594	59,713	59,857
Total maintenance revenue	274,582	279,652	282,095
Professional services:
Cloud and Edge	81,168	72,979	70,130
IP Optical Networks	30,902	28,558	24,855
Total professional services revenue	112,070	101,537	94,985
Total service revenue	386,652	381,189	377,080

Schedule of customer assets and liabilities

The changes in the Company’s accounts receivable, unbilled receivables and deferred revenue balances for the years ended December 31, 2024 and 2023 were as follows (in thousands):


			Unbilled		Deferred		Deferred
	Accounts		accounts		revenue		revenue
	receivable		receivable		(current)		(long-term)
Balance at January 1, 2024	$	186,938	$	81,483	$	113,381	$	19,218
Increase (decrease), net		(10,363)		(3,340)		5,914		1,773
Balance at December 31, 2024	$	176,575	$	78,143	$	119,295	$	20,991


			Unbilled		Deferred		Deferred
	Accounts		accounts		revenue		revenue
	receivable		receivable		(current)		(long-term)
Balance at January 1, 2023	$	170,969	$	96,275	$	113,939	$	19,254
Increase (decrease), net		15,969		(14,792)		(558)		(36)
Balance at December 31, 2023	$	186,938	$	81,483	$	113,381	$	19,218