X0508 4 2023-09-18 0001492422 Apellis Pharmaceuticals, Inc. APLS 0001496687 Machiels Alec C/O APELLIS PHARMACEUTICALS, INC. 100 FIFTH AVENUE, 3RD FLOOR WALTHAM MA 02451 1 1 Common Stock 2023-09-18 4 M 0 1250 2.67 A 368670 D Common Stock 2023-09-18 4 S 0 1250 45.00 D 367420 D Common Stock 250000 I Indirect Owner (Bauhaus 1 LLC) Common Stock 11950 I Indirect Owner (Owned by Spouse) Common Stock 150000 I Indirect Owner (Spouse Trust) Stock Option (Right to Buy) 2.67 2023-09-18 4 M 0 1250 0 D 2023-12-04 Common Stock 1250 2500 D This is a scheduled exercise and sale from 10B5-1 trading plan. The shares are held by Bauhaus 1 LLC, which LLC is held by The Irrevocable Agreement of Trust of Alec Machiels (the "Trust"). The reporting person is the managing member of Bauhaus 1 LLC and the trustee of the Trust. Owned by spouse. On September 7, 2021, the reporting person's spouse transferred 150,000 shares of Apellis Pharmaceuticals, Inc. common stock to her trust, of which the reporting person is the trustee. This option was granted on December 5, 2013 and fully vested. /s/ David Watson, attorney-in-fact for Alec Machiels 2023-09-19