X0306 4 2020-03-13 0001708055 Ribbon Communications Inc. RBBN 0001424201 McClelland Bruce William C/O RIBBON COMMUNICATIONS INC. 4 TECHNOLOGY PARK DRIVE WESTFORD MA 01886 1 1 0 0 President & CEO Common Stock 2020-03-13 4 P 0 10000 2.20 A 65575 D Common Stock 2020-03-16 4 P 0 10000 2.2578 A 75575 D Restricted Stock Units (RSUs) 2020-03-16 4 A 0 462963 0 A Common Stock 462963 462963 D Performance-Based Restricted Stock Units (PSUs) 2020-03-16 4 A 0 4750000 0 A Common Stock 4750000 4750000 D Each RSU represents a contingent right to receive one share of Ribbon Communications Inc. ("Ribbon") common stock. The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $2.55 to $2.60, inclusive. The reporting person undertakes to provide to Ribbon, any security holder of Ribbon, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price with the ranges set forth in this footnote. The RSUs shall become fully vested on the earlier of (i) March 16, 2021 and (ii) the date of the consummation of a change in control (the earlier date, the "Vesting Date"), so long as the reporting person remains actively and continuously employed by the Company or any of its subsidiaries through the Vesting Date. The PSUs vest upon Ribbon's common stock achieving sustained market prices of $7.50, $12.00, $15.00 and $20.00 per share over a consecutive twenty day period during the applicable performance period (each such date a "Performance Vesting Date"), in each case, subject to the reporting person's active and continuous employment by Ribbon or any of its subsidiaries through each applicable Performance Vesting Date; provided that no PSUs are eligible to vest after September 1, 2024. In the event that the applicable target price for a performance period is not achieved, the corresponding PSUs may still be eligible to vest in a later performance period. Bruce W. McClelland 2020-03-17