Charles S. Berkman - 01 Nov 2022 Form 4 Insider Report for OmniAb Operations, Inc.

Footnote F1

Includes 9,564 restricted stock units ("RSUs"). Each RSU represents a contingent right to receive one share of the Issuer's Common Stock and does not expire.

Footnote F2

Includes 26,789 shares of the Issuer's Common Stock received by the Reporting Person in connection with a pro-rata distribution in-kind from Ligand Pharmaceuticals Incorporated, which was exempt from reporting pursuant to Rule 16a-9.

Footnote F3

Includes securities that were adjusted pursuant to an anti-dilution provision in connection with the separation of the Issuer from Ligand Pharmacueticals Incorporated on November 1, 2022.

Footnote F4

Pursuant to the business combination of Avista Public Acquisition Corp. II (after consummation of the transaction contemplated here, "New OmniAb") and the Issuer, 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 the Issuer will automatically convert into the right to receive securities of New OmniAb with the same terms and conditions in accordance with exchange ratios described in the Merger Agreement.

Footnote F5

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.

Footnote F6

The stock option is fully vested and exercisable.

Footnote F7

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.

Footnote F8

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.

Footnote F9

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.