X0508 4/A 2024-04-17 2024-04-19 0001708055 Ribbon Communications Inc. RBBN 0001641965 Macken Patrick W 6500 CHASE OAKS BLVD. STE. 100 PLANO TX 75023 0 1 0 0 EVP, CLO & Secretary 0 Common Stock 2024-04-17 4 M 0 24257 A 234801 D Common Stock 2024-04-17 4 F 0 10372 2.61 D 224429 D Performance Share Units (PSUs) 2024-04-17 4 M 0 24257 0 D Common Stock 24257 0 D Each Performance Share Unit (PSU) converts into common stock on a one-for-one basis. Original Form 4 filing overstated the number of shares issued upon vesting of this PSU award by 2,020 shares. This amendment has been filed to correct the vesting amount and the amount shown in Column 5 reflects total shares owned after correcting this transaction. All other amounts shown on the original Form 4 filing are correct. Reflects shares of Common Stock withheld by the Issuer to satisfy tax withholding obligations in connection with the vesting. The PSUs were issued on April 17, 2023. The number of PSUs earned and vested was based on achievement of a revenue goal set (prior to grant) by the Compensation Committee of the Issuer's Board of Directors for the fiscal year ended December 31, 2023. The remaining PSUs were forfeited. Patrick Macken 2025-03-18