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* Gallagher Patrick Murphy (Last) (First) (Middle) 2850 GOLF ROAD (Street) ROLLING MEADOWS ILLINOIS 60008 (City) (State) (Zip) UNITED STATES (Country)	2. Issuer Name and Ticker or Trading Symbol Arthur J. Gallagher & Co. [ AJG ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner X Officer (give title below) Other (specify below) Chief Operating Officer
	2a. Foreign Trading Symbol
	3. Date of Earliest Transaction (Month/Day/Year) 03/20/2026	6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person
	4. If Amendment, Date of Original Filed (Month/Day/Year)

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	03/23/2026		G		704	D	$0	14,071.6637	D
Common Stock	03/23/2026		G		704	A	$0	11,264	I	By Spouse as Trustee(1)
Common Stock								491.136	I	Gallagher 401(k) plan account
Common Stock								77,062	I	By Spouse's Trust(2)
Common Stock								83,407.25	I	By Trust
Common Stock								21,032	I	By Trust(3)
Common Stock								55,109	I	By Irrevocable Trust

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
Notional Stock Units	(4)	03/20/2026		I		1,444.731(5)		(6)	(7)	Common Stock	1,444.731	$214.82	2,351.803	D
Non-qualified Stock Option	$228.2							(8)	03/01/2033	Common Stock	17,775		17,775	D
Phantom Stock	(9)							(10)	(10)	Common Stock	17,660.851		17,660.851	D
Non-qualified Stock Option	$337.74(11)							(12)	03/01/2032	Common Stock	11,901		11,901	D
Non-qualified Stock Option	$243.54							(13)	03/01/2031	Common Stock	11,386		11,386	D
Non-qualified Stock Option	$127.9							(12)(14)	03/16/2028	Common Stock	7,255		7,255	D
Non-qualified Stock Option	$86.17							(12)(15)	03/12/2027	Common Stock	6,270		6,270	D
Non-qualified Stock Option	$177.09							(16)	03/15/2030	Common Stock	6,160		6,160	D
Non-qualified Stock Option	$158.56							(12)(17)	03/15/2029	Common Stock	5,510		5,510	D
Phantom Stock	(9)							(18)	(18)	Common Stock	3,804.562		3,804.562	D

Explanation of Responses:

1. Shares held in trusts, for the benefit of the reporting person's children, of which his wife is sole trustee.

2. Shares held in a revocable trust and an irrevocable trust of which the reporting person's spouse is sole Trustee and as to which he disclaims beneficial ownership

3. Shares held in trust for the benefit of the reporting person's children, of which he is a trustee.

4. Each notional stock unit represents a right to receive one share of Gallagher common stock.

5. The reporting person moved $310,357.10 in assets that he holds in the company's Supplemental Savings and Thrift Plan, a nonqualified deferred compensation plan, into the investment option representing Gallagher common stock, which is a discretionary transaction by the reporting person.

6. The notional stock units become payable following the reporting person's separation from service with Gallagher.

7. The notional stock units become payable following the reporting person's separation from service with Gallagher.

8. One-third of this stock option becomes exercisable on each of the 3rd, 4th, and 5th anniversaries of the grant date.

9. Each share of phantom stock represents a right to receive one share of Gallagher common stock.

10. These shares represent awards under the Age 62 Plan, a nonqualified deferred compensation plan of the Company, which have been deemed invested in Company common stock at the election of the reporting person. Participants vest in these awards when they attain age 62, or after a one-year period for participants who have attained age 61.

11. Closing price of Gallagher common stock on February 28, 2025.

12. One-third of this stock option becomes exerciseable on each of the 3rd, 4th, and 5th anniversaries of the grant date.

13. One-third of this stock option becomes exercisable on each of the 3rd, 4th, and 5th anniversaries of the grant date.

14. Grant date of 3/16/2021.

15. Grant date of 3/12/2020.

16. One-third of this stock option becomes exercisable on each of the 3rd, 4th, and 5th anniversaries of the grant date.

17. Grant date of 3/15/2022.

18. These shares represent awards under the Deferred Cash Participation Plan, a nonqualified deferred compensation plan of the Company, which have been deemed invested in Company common stock at the election of the participant. These awards are payable in a lump sum on the six-month anniversary of the reporting person's separation from service.

Remarks:

The reporting person moved $310,357.10 in assets that he holds in the company's Supplemental Savings and Thrift Plan, a nonqualified deferred compensation plan, into the investment option representing Gallagher common stock, which is a discretionary transaction by the reporting person.

	/s/ Monica Norzagaray, by power of attorney	03/24/2026
	** Signature of Reporting Person	Date
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* Form 4: SEC 1474 (03-26)