X0609 4 2026-10-01 0001370053 ANAPTYSBIO, INC ANAB 0001187333 RENTON HOLLINGS false C/O ANAPTYSBIO, INC. 10770 WATERIDGE CIRCLE, SUITE 210 SAN DIEGO CA 92121 true false false false 1 Common Stock 2026-10-01 4 M 0 5000 18.03 A 15995 D Common Stock 2026-10-01 4 S 0 5000 49.8743 D 10995 D Common Stock 18.03 2026-10-01 4 M 0 5000 0 D 2027-02-23 Common Stock 5000 10000 D The sale reported on this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on March 30, 2026. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $49.435 to $50.37 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. The stock option is fully vested and exercisable. In addition to the remaining options to purchase 10,000 shares of common stock as set forth in Table II, the Reporting Person also holds additional options to purchase up to an aggregate of 92,320 shares of common stock, which options vest according to their terms. /s/ Christopher Murphy, Attorney-in-Fact 2026-10-02