X0306 4 2022-11-01 0 0001846253 OmniAb, Inc. OABI 0001392266 Berkman Charles S C/O OMNIAB, INC. 5980 HORTON STREET, SUITE 600 EMERYVILLE CA 94608 0 1 0 0 See Remarks Common Stock 2022-11-01 4 A 0 353716 A 353716 D Stock Option 6.46 2022-11-01 4 A 0 8339 A 2025-02-10 Common Stock 8339 8339 D Stock Option 9.84 2022-11-01 4 A 0 17778 A 2026-02-11 Common Stock 17778 17778 D Stock Option 11.52 2022-11-01 4 A 0 29237 A 2027-02-24 Common Stock 29237 29237 D Stock Option 18.24 2022-11-01 4 A 0 39777 A 2028-03-02 Common Stock 39777 39777 D Stock Option 13.54 2022-11-01 4 A 0 62710 A 2029-02-11 Common Stock 62710 62710 D Stock Option 10.98 2022-11-01 4 A 0 73716 A 2030-02-13 Common Stock 73716 73716 D Stock Option 20.36 2022-11-01 4 A 0 29772 A 2031-02-03 Common Stock 29772 29772 D Stock Option 10.41 2022-11-01 4 A 0 175477 A 2032-05-05 Common Stock 175477 175477 D Pursuant to the business combination of Avista Public Acquisition Corp. II and OmniAb, Inc. ("Legacy OmniAb"), as contemplated by an agreement and plan of merger, dated March 23, 2022 (the "Merger Agreement"), each share of common stock, option and award of restricted stock unit of Legacy OmniAb automatically converted into the right to receive securities of the Issuer with the same terms and conditions in accordance with an exchange ratio described in the Merger Agreement. Includes 97,769 restricted stock units ("RSUs"). Each RSU represents a contingent right to receive one share of the Issuer's Common Stock and does not expire. Includes 96,038 earn-out shares subject to forfeiture provisions described in the Merger Agreement. The stock option is fully vested and exercisable. The stock option vests and is exercisable as to 12.5% of the underlying shares on August 11, 2019, and in 42 substantially equal monthly installments thereafter. The stock option vests and is exercisable as to 12.5% of the underlying shares on August 13, 2020, and in 42 substantially equal monthly installments thereafter. The stock option vests and is exercisable as to 12.5% of the underlying shares on August 3, 2021, and in 42 substantially equal monthly installments thereafter. The stock option vests and is exercisable as to 12.5% of the underlying shares on August 5, 2022, and in 42 substantially equal monthly installments thereafter. Chief Legal Officer and Secretary /s/ Charles S. Berkman 2022-11-03