X0206 3 2020-10-01 0 0001662579 C4 Therapeutics, Inc. CCCC 0001132945 COHEN MARC A C/O C4 THERAPEUTICS, INC. 490 ARSENAL WAY, SUITE 200 WATERTOWN MA 02472 1 1 1 0 Chief Executive Officer Common Stock 132875 I See Footnote Series Seed Preferred Stock Common Stock 237149 I See Footnote Series A Preferred Stock Common Stock 1482183 I See Footnote Series B Preferred Stock Common Stock 2484425 I By Cobro Ventures Opportunity Fund, L.P. Stock Option (Right to Buy) 2.11 2026-07-12 Common Stock 3745 D Shares held by Reporting Person as trustee of the Marc Andrew Cohen Revocable Trust. The Reporting Person disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein. Each share of Series Seed Preferred Stock, Series A Preferred Stock, and Series B Preferred Stock is convertible into Common Stock on a 8.4335-to-one basis into the number of shares of Common Stock shown in Column 3 at any time at the holder's election, and automatically upon the closing of the Issuer's initial public offering without payment or further consideration. The shares have no expiration date. Shares held by Cobro Ventures Opportunity Fund, L.P. ("Cobro Ventures"). The Reporting Person serves as a manager of Cobro Opportunity Fund GP, LLC, the general partner of Cobro Ventures, and may be deemed to exercise voting and investment power over the shares held by Cobro Ventures. The Reporting Person disclaims beneficial ownership of the shares held by Cobro Ventures except to the extent of his pecuniary interest therein. Represents underlying unexercised stock options that were granted on July 13, 2016. The terms of the original grant provide that 12.5% of this option vested and became exercisable on December 31, 2016, with the remainder vesting in 28 equal quarterly installments thereafter, subject to the Reporting Person's continuous service through each such date. Exhibit 24 - Power of Attorney /s/ Jolie M. Siegel, Attorney-in-Fact 2020-10-01