X0306 4 2022-06-08 0 0001370053 ANAPTYSBIO, INC ANAB 0001239648 LOUMEAU ERIC J C/O ANAPTYSBIO, INC. 10770 WATERIDGE CIRCLE, SUITE 210 SAN DIEGO CA 92121 0 1 0 0 COO, General Counsel Common Stock 2022-06-08 4 M 0 2500 14.02 A 3023 D Common Stock 2022-06-08 4 S 0 2500 24.00 D 523 D Employee Stock Option (Right to Buy) 14.02 2022-06-08 4 M 0 2500 0.00 D 2029-12-05 Common Stock 2500 83000 D The transactions reported on this Form 4 were effected pursuant to a 10b5-1 trading plan adopted by the reporting person. The stock option vested and is exercisable as to 25% of the shares subject to the option on December 6, 2020, and thereafter vests as to 1/48th of the shares in equal monthly installments, until such time as the option is 100% vested, subject to the continuing employment of the Reporting Person on each vesting date. In addition to the remaining options to purchase 83,000 shares of common stock as set forth in Table II, the Reporting Person also holds additional options to purchase up to an aggregate of 215,000 shares of common stock, which options vest according to their terms. /s/ Eric Loumeau 2022-06-10