X0407 4 2023-07-03 0001492422 Apellis Pharmaceuticals, Inc. APLS 0001707000 Sullivan Timothy Eugene C/O APELLIS PHARMACEUTICALS, INC. 100 FIFTH AVENUE, 3RD FLOOR WALTHAM MA 02451 1 Chief Financial Officer 1 Common Stock 2023-07-03 4 M 0 6779 10.03 A 84492 D Common Stock 2023-07-03 4 S 0 3192 89.4109 D 81300 D Common Stock 2023-07-03 4 S 0 3287 90.4165 D 78013 D Common Stock 2023-07-03 4 S 0 300 91.0983 D 77713 D Common Stock 56232 I The Timothy E Sullivan Irrevocable Trust of 2023 Stock Option (Right to Buy) 10.03 2023-07-03 4 M 0 6779 0 D 2027-10-18 Common Stock 6779 282061 D This is a scheduled exercise & sale from 10b5-1 trading plan. This transaction was executed in multiple trades at prices ranging from $88.960 - $89.890. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. This transaction was executed in multiple trades at prices ranging from $89.980 - $90.940. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. This transaction was executed in multiple trades at prices ranging from $91.075 - $91.110. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. The securities are held by The Timothy E Sullivan Irrevocable Trust of 2023. Patrick O. Collins is the trustee of The Timothy E Sullivan Irrevocable Trust of 2023. The reporting person disclaims beneficial ownership over the shares held by The Timothy E Sullivan Irrevocable Trust of 2023 except to the extent of his pecuniary interest therein. This option was granted on October 18, 2017 and fully vested. /s/s David Watson, attorney-in-fact for Timothy Sullivan 2023-07-06