X0508 4 2025-12-16 0 0000886163 LIGAND PHARMACEUTICALS INC LGND 0001905248 Espinoza Octavio 555 HERITAGE DRIVE SUITE 200 JUPITER FL 33458 0 1 0 0 Chief Financial Officer 0 Common Stock 2025-12-16 4 M 0 1194 52.84 A 27380 D Common Stock 2025-12-16 4 M 0 69 57.22 A 27449 D Common Stock 2025-12-16 4 M 0 285 63.62 A 27734 D Common Stock 2025-12-16 4 M 0 652 92.65 A 28386 D Common Stock 2025-12-16 4 M 0 181 103.42 A 28567 D Employee Stock Option (right to buy) 52.84 2025-12-16 4 M 0 1194 0.0 D 2032-05-05 Common Stock 1194 972 D Employee Stock Option (right to buy) 57.22 2025-12-16 4 M 0 69 0.0 D 2030-10-01 Common Stock 69 7171 D Employee Stock Option (right to buy) 63.62 2025-12-16 4 M 0 285 0.0 D 2032-12-13 Common Stock 285 18171 D Employee Stock Option (right to buy) 92.65 2025-12-16 4 M 0 652 0.0 D 2028-03-02 Common Stock 652 2405 D Employee Stock Option (right to buy) 103.42 2025-12-16 4 M 0 181 0.0 D 2031-02-03 Common Stock 181 4186 D The stock option vests as to approximately 55% of the underlying shares in 12 substantially equal monthly installments beginning on January 5, 2025, and approximately 45% of the underlying shares in two substantially equal monthly installments thereafter. As per the separation of OmniAb Inc. from the issuer, 4,096 stock options were vested and exercisable as of November 1, 2022, whereas 3,766 options vest in 23 substantially equal monthly installments beginning on December 1, 2022. Grant to reporting person of stock options that will vest and become exercisable over a 4-year period measured from December 5, 2022, with 12-1/2% of the shares subject to the stock options vesting on the date that is six months after December 5, 2022 and the remaining stock options vesting in 42 equal monthly installments thereafter. The stock option is fully vested and exercisable. The stock option vests as to 50% of the underlying shares on January 3, 2025 and as to the remaining on February 3, 2025. By: /s/ Andrew Reardon, Attorney-in-Fact For: Octavio Espinoza 2025-12-18