Transactions Table

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Explanation of Responses:

Id	Content
F1	This form is being filed by each of the following Reporting Persons: (i) Avista Acquisition LP II, a Cayman Islands limited partnership ("Avista Sponsor"), (ii) Avista Acquisition GP LLC II, a Cayman Islands limited liability company ("Avista Sponsor GP"), which is the general partner of Avista Sponsor, (iii) Avista Capital Partners V, L.P., a Delaware limited partnership ("ACP V Onshore"), which is a limited partner of Avista Sponsor, (iv) Avista Capital Partners (Offshore) V, L.P., a Bermuda limited partnership ("ACP V Offshore"), which is a limited partner of Avista Sponsor, (v) Avista Capital Partners V GP, L.P., a Delaware limited partnership ("ACP V GP"), which is the general partner of ACP V Onshore and ACP V Offshore,
F2	(vi) Avista Capital Managing Member V, LLC, a Delaware limited liability company ("Avista Managing Member"), which is the general partner of ACP V VP, (vii) each of Thompson Dean and David Burgstahler, who are the managers of Avista Sponsor GP and Avista Managing Member (together with ACP V Onshore, ACP V Offshore, ACP V GP and Avista Managing Member, the "Avista Affiliates"), and (viii) Joshua Tamaroff, who is a Director of OmniAb, Inc. (f/k/a Avista Public Acquisition Corp. II) (the "Issuer").
F3	Each of the transactions described in this Form 4 are being made in connection with the liquidation and dissolution of Avista Sponsor and Avista Sponsor GP. In connection with its liquidation, Avista Sponsor distributed all of its assets, consisting solely of securities of the Issuer, pro rata for no consideration to its limited partners, ACP V Onshore and ACP V Offshore. As a result of these transactions and their subsequent dissolution, Avista Sponsor and Avista Sponsor GP will no longer hold, directly or indirectly, any securities in the Issuer.
F4	Each of the transactions described in this Form 4 are being made in connection with the liquidation and dissolution of Avista Sponsor and Avista Sponsor GP. In connection with its liquidation, Avista Sponsor distributed all of its assets, consisting solely of securities of the Issuer, pro rata for no consideration to its limited partners, ACP V Onshore and ACP V Offshore. As a result of these transactions and their subsequent dissolution, Avista Sponsor and Avista Sponsor GP will no longer hold, directly or indirectly, any securities in the Issuer.
F5	Directly owned by ACP V Offshore. Each of the Avista Affiliates may be deemed to beneficially own the securities reported on this line item to the extent of their respective pecuniary interests. Each of the Avista Affiliates disclaims beneficial ownership of the securities reported on this line item, except to the extent of their pecuniary interest therein, if any.
F6	In accordance with the letter agreement, dated March 23, 2022, among the Issuer, Avista Sponsor, Legacy OmniAb and other parties (the "Letter Agreement"), if the Triggering Event (as defined in the Letter Agreement) has not occurred during the Earnout Period (as defined in the Letter Agreement), 1,293,299 shares of common stock will be automatically forfeited to the Issuer for no consideration. As a result of the transactions described in this Form 4, and pursuant to a Joinder to the Letter Agreement entered into on December 9, 2022 between ACP V Onshore, ACP V Offshore, Avista Sponsor and the Issuer, ACP V Onshore directly holds 595,508 of the shares of common stock subject to forfeiture pursuant to the terms of the Letter Agreement, and ACP V Offshore holds 697,791 of the shares of common stock subject to forfeiture pursuant to the terms of the Letter Agreement.
F7	Additionally, in connection with the transactions described in this Form 4, each of ACP V Onshore and ACP V Offshore provided to the Issuer an agreement stating that they will each be bound by the transfer restrictions included in the Amended and Restated Registration and Stockholder Rights Agreement, dated as of November 1, 2022, among the Issuer, the Sponsor and the other signatories thereto (the "A&R RSRA") for the duration of the Founder Shares Lock Up Period (as defined in the A&R RSRA).
F8	Represents stock options granted to Joshua Tamaroff in his capacity as a director of the Issuer, which stock options vest in three substantially similar annual installments beginning on November 1, 2023. Mr. Tamaroff is a partner at an affiliate of the Avista Affiliates and has assigned all rights, title and interest in such stock options to an affiliate of the Avista Affiliates controlled by Mr. Dean and Mr. Burgstahler. The Avista Affiliates are each "directors by deputization" for the purposes of Section 16 of the Securities Exchange Act of 1934, as amended. Each of the Avista Affiliates and Josh Tamaroff may be deemed to beneficially own the securities reported on this line item to the extent of their respective pecuniary interests. Each of the Avista Affiliates and Josh Tamaroff disclaims beneficial ownership of the securities reported on this line item, except to the extent of their pecuniary interest therein, if any.
F9	In connection with the completion of the Issuer's August 2021 initial public offering, Avista Sponsor purchased 8,233,333 warrants in a private placement from the Issuer, each exercisable to purchase (subject, initially, to the satisfaction of certain material conditions) one Class A ordinary share, par value $0.0001 per share, of the Issuer for $11.50 per share. The material conditions to exercise were satisfied upon the closing of the transactions contemplated by the Merger Agreement (the "Closing"), and the warrants by their terms became exercisable (including by cash settlement) on December 1., 2022.
F10	In connection with the Amended and Restated Forward Purchase Agreement, dated March 23, 2022, by and among the Issuer, Avista Sponsor and OmniAb, Inc.(the "A&R Forward Purchase Agreement"), Avista Sponsor purchased an aggregate 3,112,156 warrants in private placements from the Issuer, each exercisable to purchase (subject, initially, to the satisfaction of certain material conditions) one share of common stock, par value $0.0001 per share, of the Issuer for $11.50 per share. The material conditions to exercise were satisfied on the Closing, and the warrants by their terms became exercisable (including by cash settlement) December 31, 2022.

Remarks:

Exhibit 24.1 (Power of Attorney) and Exhibit 99.1 (Joint Filer Information and Signatures) are hereby incorporated by reference herein.