X0306 4 2022-11-09 0 0001060736 Seagen Inc. SGEN 0001741836 DANSEY ROGER D 21823 30TH DRIVE SE BOTHELL WA 98021 0 1 0 0 See Remarks Non-Qualified Stock Option (Right to Buy) 137.96 2022-11-09 4 A 0 275000 0.00 A 2032-11-09 Common Stock 275000 275000 D Options are subject to performance vesting in tranches tied to price targets for shares of the Issuer's common stock generally achievable on specified timelines on or before December 31, 2028 or an earlier change of control of the Issuer. Each such tranche will time-vest 1/3 on the date of performance vesting, 1/3 on the 9 month anniversary of performance vesting and 1/3 on the 18 month anniversary of performance vesting. President, Research & Development & Chief Medical Officer /s/ Jennifer Prosba, for Roger D. Dansey 2022-11-14