X0306 4 2020-12-01 0 0001622229 Cogent Biosciences, Inc. COGT 0001709773 Green John L. C/O COGENT BIOSCIENCES, INC. 200 CAMBRIDGE PARK DRIVE, SUITE 2500 CAMBRIDGE MA 02140 0 1 0 0 Chief Financial Officer Common Stock 2020-12-01 4 A 0 1748 0.00 A 1748 D Reflects shares of common stock issued to the Reporting Person in accordance with the terms of the Contingent Value Rights distributed to certain stockholders pursuant to the Contingent Value Rights Agreement on July 6, 2020. Exhibit 24 - Power of Attorney /s/ Ryan Murr, Attorney-in-Fact 2020-12-07