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 Expires: December 31, 2014 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).

1. Name and Address of Reporting Person * GALLAGHER J PATRICK JR (Last) (First) (Middle) 2850 GOLF ROAD (Street) ROLLING MEADOWS IL 60008-4002 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Arthur J. Gallagher & Co. [ AJG ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director 10% Owner X Officer (give title below) Other (specify below) CEO
	3. Date of Earliest Transaction (Month/Day/Year) 03/31/2026
	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	03/31/2026		M		5,345.903	A	$ 215.95	126,330.8365	D
Common Stock	03/31/2026		F		2,369	D	$ 215.95	123,961.8365 (1)	D
Common Stock								5,328	I	By Spouse's Trust (2)
Common Stock								255,965	I	By Corporation
Common Stock								66,703	I	By Irrevocable Trust
Common Stock								270,175	I	By Spouse (3)
Common Stock								219,955	I	By Trust (4)
Common Stock								491.142	I	Gallagher 401(k) plan account

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
Phantom Stock	(5)	03/31/2026		M			5,345.903	(6)	(6)	Common Stock	5,345.903	$ 0	139,097.882	D
Notional Stock Units	$ 0 (7)							(8)	(8)	Common Stock	153,788.107		153,788.107	D
Non-qualified Stock Option	$ 127.9							(9)	03/16/2028	Common Stock	76,975		76,975	D
Non-qualified Stock Option	$ 86.17							(9)	03/12/2027	Common Stock	68,550		68,550	D
Non-qualified Stock Option	$ 228.2							(10)	03/01/2033	Common Stock	48,449		48,449	D
Non-qualified Stock Option	$ 158.56							(9)	03/15/2029	Common Stock	35,825		35,825	D
Non-qualified Stock Option	$ 177.09							(11)	03/15/2030	Common Stock	30,029		30,029	D
Non-qualified Stock Option	$ 243.54							(12)	03/01/2031	Common Stock	27,210		27,210	D
Non-qualified Stock Option	$ 337.74							(9)	03/01/2032	Common Stock	22,727		22,727	D

Explanation of Responses:

1. The transactions in this report relate solely to the distribution of vested shares under the Age 62 Plan and the withholding of shares to cover applicable income and employment taxes.

2. Shares held in trust for the benefit of my children of which I am sole Trustee.

3. Shares held in revocable trust of which my spouse is sole Trustee and as to which I disclaim beneficial ownership.

4. Held in trust for benefit of children.

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

6. 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.

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

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

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

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

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

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

Remarks:

The transactions in this report relate solely to the distribution of vested shares under the Age 62 Plan and the withholding of shares to cover applicable income and employment taxes.

	/s/ Monica Norzagaray, by power of attorney	04/01/2026
	** Signature of Reporting Person	Date
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