X0306 4 2021-07-20 0 0001761918 Erasca, Inc. ERAS 0001455228 Casdin Alexander W. C/O ERASCA, INC. 10835 ROAD TO THE CURE, SUITE 140 SAN DIEGO CA 92121 1 0 0 0 Common Stock 2021-07-20 4 C 0 150000 A 337500 D Common Stock 2021-07-20 4 C 0 750000 A 750000 I By Reneo SPV IV LP Series A Preferred Stock 0.00 2021-07-20 4 C 0 180000 D Common Stock 150000 0 D Series A Preferred Stock 0.00 2021-07-20 4 C 0 900000 D Common Stock 750000 0 I By Reneo SPV IV LP The shares of the Issuer's Series A Preferred Stock automatically converted into shares of the Issuer's Common Stock, for no additional consideration, at a ratio of 1.2-for-1 share, immediately prior to the consummation of the Issuer's initial public offering. Alexander Casdin serves as the managing member of Reneo GP LLC, which is the general partner of Reneo Capital SPV IV LP (Reneo SPV). Mr. Casdin exercises voting and dispositive control over the securities held by Reneo SPV and is therefore deemed to be a beneficial owner of securities owned by Reneo SPV. Mr. Casdin disclaims beneficial ownership of the reported securities held by Reneo SPV, except to the extent of his pecuniary interest therein. /s/ Ebun S. Garner, Attorney-in-Fact 2021-07-20