X0206 3 2023-08-28 0 0001831915 Cytek Biosciences, Inc. CTKB 0001991396 Busque Philippe C/O CYTEK BIOSCIENCES, INC. 47215 LAKEVIEW BLVD. FREMONT CA 94538 0 1 0 0 SVP, Global Sales and Services Restricted Stock Units Common Stock 24590 D Restricted Stock Units Common Stock 5464 D Employee Stock Option (right to buy) 9.15 2033-03-20 Common Stock 37562 D The shares subject to the Restricted Stock Units (the "RSU Award") shall vest over four years with 13/48 of the total shares underlying the RSU Award vesting on May 18, 2024; 3/48 of the total shares underlying the RSU Award vesting on August 18, 2024 and each August 18 thereafter; 3/48 of the total shares underlying the RSU Award vesting on November 18, 2024 and each November 18 thereafter; 4/48 of the total shares underlying the RSU Award vesting on March 10, 2025 and each March 10 thereafter; and 2/48 of the total shares underlying the RSU Award vesting on May 18, 2025 and each May 18 thereafter. Each RSU Award represents a contingent right to receive one share of the Issuer's common stock. The shares subject to the RSU Award shall vest on March 20, 2024. The shares subject to the option vest as follows: 25% of the shares subject to the option vests on March 20, 2024; and 1/48th of the shares subject to the option vest monthly thereafter over the following three years. /s/ Valerie Barnett, Attorney-in-Fact for Philippe Busque 2023-08-29