[Form 4] OmniAb, Inc. Insider Trading Activity

Rhea-AI Filing Summary

OmniAb (OABI) disclosed that a director reported the vesting and settlement of 17,769 restricted stock units into common stock on November 1, 2025 (transaction code M).

Following the transaction, the director beneficially owns 93,308 shares directly and holds 20,000 RSUs. The RSU award vests in three substantially equal annual installments beginning November 1, 2023, subject to continued service. The filing was made by one reporting person with direct ownership.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Bertozzi Carolyn R

(Last) (First) (Middle)

5980 HORTON STREET, STE 600

(Street)

EMERYVILLE CA 94608

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
OmniAb, Inc. [ OABI ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
11/01/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	11/01/2025		M		17,769(1)	A	(2)	93,308	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Restricted Stock Units	(2)	11/01/2025		M			17,769	(1)	(1)	Common Stock	17,769	$0	20,000	D

Explanation of Responses:

1. Represents the vesting of an RSU which occurs in three substantially equal annual installments, beginning November 1st, 2023, subject to the Reporting Person's continued service to the Issuer through each such vesting date.

2. Each Restricted Stock Unit ("RSU") represents a contingent right to receive one share of the Issuer's Common Stock.

Remarks:

	By: /s/ Charles S. Berkman, Attorney-in-Fact For: Carolyn R Bertozzi	11/03/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did OmniAb (OABI) disclose in this Form 4?

A director reported the vesting and settlement of 17,769 RSUs into common stock on November 1, 2025 (code M).

How many OmniAb shares does the reporting person hold after the transaction?

The reporting person beneficially owns 93,308 shares directly after the transaction.

How many RSUs remain after this vesting event for OABI?

The reporting person holds 20,000 RSUs following the reported transaction.

What is the vesting schedule for the RSUs reported by the OmniAb director?

They vest in three substantially equal annual installments beginning November 1, 2023, subject to continued service.

What was the transaction code used in the OABI Form 4?

Transaction code M, indicating a conversion or settlement of a derivative security.

What is the reporting person’s relationship to OmniAb (OABI)?

The reporting person is a Director of OmniAb.