KURT A. GUSTAFSON - 07 Dec 2025 Form 4 Insider Report for OmniAb, Inc. (OABI)

Role
Executive VP, Finance and CFO
Signature
By: /s/ Charles S. Berkman, Attorney-in-Fact For: Kurt A. Gustafson
Issuer symbol
OABI
Transactions as of
07 Dec 2025
Transactions value $
-$46,887
Form type
4
Filing time
09 Dec 2025, 09:02:09 UTC
Previous filing
16 Jun 2025
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
GUSTAFSON KURT A Executive VP, Finance and CFO 5980 HORTON STREET, STE 600, EMERYVILLE By: /s/ Charles S. Berkman, Attorney-in-Fact For: Kurt A. Gustafson 09 Dec 2025 0001462354

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction OABI Common Stock Options Exercise $0 +46.5K +20.21% $0.00 277K 07 Dec 2025 Direct F1, F2, F3
transaction OABI Common Stock Sale -$46.9K -23.9K -8.65% $1.96 253K 08 Dec 2025 Direct F4, F5

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

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction OABI Restricted Stock Units Options Exercise $0 -46.5K -32.43% $0.00 96.9K 07 Dec 2025 Common Stock 46.5K $0.00 Direct F1, F2
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Represents the vesting of an RSU grant which occurs in three substantially equal annual installments beginning on December 7, 2023.
F2 Each Restricted Stock Unit ("RSU") represents a contingent right to receive one share of the Issuer's Common Stock.
F3 The total includes 6,282 shares acquired on May 30, 2025 and November 28, 2025, through the Issuer's Employee Stock Purchase Plan (ESPP).
F4 Represents the number of shares required to be sold by the reporting person to cover tax withholding obligations in connection with the vesting of RSUs. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of a tax withholding obligation to be funded by a "sell-to-cover" transaction and do not represent discretionary trades by the reporting person.
F5 The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $1.94 to $2.01. The reporting person undertakes to provide the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.