X0306 4 2022-07-15 0001708055 Ribbon Communications Inc. RBBN 0001600024 LOPEZ MIGUEL A C/O RIBBON COMMUNICATIONS INC. 6500 CHASE OAKS BOULEVARD, SUITE 100 PLANO TX 75023 0 1 0 0 EVP, CFO Common Stock 2022-07-15 4 M 0 16593 A 114120 D Common Stock 2022-07-15 4 F 0 5928 3.18 D 108192 D Restricted Stock Units (RSU) 2022-07-15 4 M 0 16593 0 D Common Stock 16593 33185 D RSUs convert to common stock on a one-for-one basis. Reflects shares of Common Stock withheld by the Issuer to satisfy tax withholding obligations in connection with the vesting of RSUs. The RSUs vest over a three-year period as follows: one-third of the restricted stock units vested on July 15, 2021, and the remaining two-thirds of the RSUs vest in four equal, semi-annual installments thereafter through July 15, 2023. Patrick Macken, Attorney-in-Fact 2022-07-19