Sec Form 4 Filing - Scarfo Anthony @ Ribbon Communications Inc. - 2022-06-15

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person Scarfo Anthony 2. Issuer Name and Ticker or Trading Symbol Ribbon Communications Inc. [ RBBN] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) EVP & GM, Cloud & Edge BU (Last) (First) (Middle) C/O RIBBON COMMUNICATIONS, 6500 CHASE OAKS BLVD., SUITE 100 3. Date of Earliest Transaction (MM/DD/YY) 06/15/2022 (Street) PLANO, TX75023 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 06/17/2022 M 13,528 A 230,906 D Common Stock 06/17/2022 F 3,768 D $ 2.76( 2 ) 227,138 D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares Performance-Based Restricted Stock Unit (PSU) ( 3 ) 06/15/2022 A 67,524 ( 3 ) ( 3 ) Common Stock 67,524 $ 0 67,524 D PSU ( 4 ) 06/15/2022 A 45,016 ( 4 ) ( 4 ) Common Stock 45,016 $ 0 45,016 D PSU ( 5 ) 06/15/2022 A 97,668 ( 5 ) ( 5 ) Common Stock 97,668 $ 0 97,668 D RSUs ( 6 ) 06/17/2022 M 13,528 ( 6 ) ( 6 ) Common Stock 13,528 $ 0 0 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Scarfo Anthony C/O RIBBON COMMUNICATIONS 6500 CHASE OAKS BLVD., SUITE 100 PLANO, TX75023 EVP & GM, Cloud & Edge BU Signatures Patrick Macken, Attorney-in-Fact 06/17/2022 Signature of Reporting Person Date

Explanation of Responses:

( 1 )The RSUs convert into common stock on a one-for-one basis. ( 2 )Reflects shares of Common Stock withheld by the Issuer to satisfy tax withholding obligations in connection with the vesting of RSUs. ( 3 )Each PSU represents a contingent right to receive one share of the Issuer's Common Stock. The number of PSUs earned and issuable upon vesting will be determined based on goals (set by the Compensation Committee of the Issuer's Board of Directors (the "Compensation Committee") on an annual basis) for each of the three fiscal years prior to the vesting date. The aggregate number of shares issued may range from zero shares to 200% of the target number of shares reported in columns 5, 7 and 9 of Table II. The number of PSUs reported in columns 5, 7 and 9 of Table II reflects achievement at the target level of performance. This PSU will vest on 03/15/2025. ( 4 )Each PSU represents a contingent right to receive one share of the Issuer's Common Stock, based on the Issuer's total shareholder return (TSR) compared to pre-established relative TSR goals, based on the TSR of a peer index of companies (set by the Compensation Committee at the time of grant) over the three fiscal years ending prior to the vesting date. The aggregate number of shares issued may range from zero shares to 200% of the target number of shares reported in columns 5, 7 and 9 of Table II. The number of PSUs reported in columns 5, 7 and 9 of Table II reflects achievement at the target level of performance. This PSU will vest on 03/15/2025. ( 5 )Each PSU represents a contingent right to receive one share of the Issuer's Common Stock. The number of PSUs earned and issuable upon vesting will be determined based on achievement of a revenue goal set (prior to grant) by the Compensation Committee for the fiscal year ending December 31, 2022. The aggregate number of shares issued may range from zero shares to 200% of the target number of shares reported in columns 5, 7 and 9 of Table II. The number of PSUs reported in columns 5, 7 and 9 of Table II reflects achievement at the target level of performance. This PSU will vest on 03/15/2023. ( 6 )The RSUs vested over three years following the date of grant and are now fully vested.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

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