UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

 

SCHEDULE 14A

 

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934 (Amendment No.      )

 

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Filed by a Party other than the Registrant ¨

 

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Preliminary Proxy Statement

 

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Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

 

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Definitive Proxy Statement

 

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Definitive Additional Materials

 

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Soliciting Material under §240.14a-12

 

Ribbon Communications Inc.

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