X0306 4 2022-05-09 0 0001333835 Casa Systems Inc CASA 0001723982 Chen Weidong C/O CASA SYSTEMS, INC. 100 OLD RIVER ROAD ANDOVER MA 01810 0 1 0 0 Chief Technology Officer Restricted Stock Units 2022-05-09 4 A 0 321875 0.00 A Common Stock 321875 321875 D Stock option (right to buy) 3.60 2022-05-09 4 A 0 200000 0.00 A 2032-05-08 Common Stock 200000 200000 D Each Restricted Stock Unit ("RSU") represents the right to receive one share of common stock, $0.001 par value per share (the "Common Stock") of Casa Systems, Inc. (the "Company") upon vesting, subject to the reporting person's continued service relationship with the Company and the other terms and conditions set forth in the applicable RSU agreement. In the sole discretion of the Company's board of directors, the Company may, with respect to any applicable vesting date, deliver to the reporting person Common Stock or cash having a fair market value equal to the number of shares of Common Stock underlying the portion of the RSU that vested on such date, payable within 30 days of the vesting date, less applicable taxes. These RSUs are scheduled to vest over four years, with 25% of the shares underlying the award vesting on January 1, 2023, and 25% of the shares underlying the award vesting at the end of each successive one-year period thereafter. The RSUs have no expiration date. Fifty percent of the option shares shall vest and become exercisable on January 1, 2023, and the remaining 50% of the option shares shall vest and become exercisable on January 1, 2024. Exhibit 24 - Power of Attorney /s/ Timothy C. Rodenberger, as Attorney-in-Fact 2022-05-11