X0306 4 2022-02-23 0 0001662579 C4 Therapeutics, Inc. CCCC 0001586707 Hirsch Andrew C/O C4 THERAPEUTICS, INC. 490 ARSENAL WAY #200 WATERTOWN MA 02472 1 1 0 0 President & CEO Performance Restricted Stock Units 2022-02-23 4 A 0 87500 0.00 A 2025-02-28 Common Stock 87500 87500 D Each performance restricted stock unit ("PRSU") represents the contingent right to receive one share of the Issuer's Common Stock upon vesting and settlement. 15,000 PRSUs shall vest upon satisfaction of three escalating share price vesting milestones, and the remaining 72,500 PRSUs shall vest upon satisfaction of certain discovery and clinical milestones. /s/ Jolie M. Siegel, Attorney-in-Fact 2022-02-23