X0306 4 2021-02-26 0001708055 Ribbon Communications Inc. RBBN 0001720721 Marmurek Eric S C/O RIBBON COMMUNICATIONS INC. 4 TECHNOLOGY PARK DRIVE WESTFORD MA 01886 0 1 0 0 SVP, CAO Performance Based Restricted Stock Units (PSUs) 2021-02-26 4 A 0 9085 0 A Common Stock 9085 11301 D PSUs 2021-02-26 4 A 0 11442 0 A Common Stock 11442 11442 D 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 (the "Compensation Committee") of the Issuer's Board of Directors on an annual basis for each of the three fiscal years prior to the vesting date. The Compensation Committee determined that the 2020 pre-bonus adjusted EBITDA (50% weighting) and Revenue (50% weighting) metrics resulted in a combined 125% level of the target awards being earned for the 2020 financial performance period, subject to no material changes in connection with the finalization of the audit and the filing of the Issuer's Annual Report on Form 10-K for the year ended December 31, 2020 (the "2020 Form 10-K"). The 2020 Form 10-K was filed with the U.S. Securities and Exchange Commission on February 26, 2021. As a result, Mr. Marmurek earned 9,085 shares for the 2020 performance year portion of awards made in 2019, pending his continued employment with the Issuer through the vesting date (third anniversary of the date of grant). The Compensation Committee determined that the 2020 pre-bonus adjusted EBITDA (50% weighting) and Revenue (50% weighting) metrics resulted in a combined 125% level of the target awards being earned for the 2020 financial performance period, subject to no material changes in connection with the finalization of the audit and the filing of the Issuer's Annual Report on Form 10-K for the year ended December 31, 2020 (the "2020 Form 10-K"). The 2020 Form 10-K was filed with the U.S. Securities and Exchange Commission on February 26, 2021. As a result, Mr. Marmurek earned 11,442 shares for the 2020 performance year portion of awards made in 2020, pending his continued employment with the Issuer through the vesting date (third anniversary of the date of grant). Patrick Macken, Attorney-in-Fact 2021-03-02