Arthur J. Gallagher & Co. — Director's Dealing 2025

Dec 23, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Arthur J. Gallagher & Co. (AJG)
CIK: 0000354190
Period of Report: 2025-12-19

Reporting Person: Bay Walter D. (General Counsel)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-12-19	Common Stock	M	15850	$79.59	Acquired	95399	Direct
2025-12-19	Common Stock	S	15850	$255.00	Disposed	79549	Direct
2025-12-19	Common Stock	G	1724	—	Disposed	77825	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2025-12-19	Non-qualified Stock Option	$79.59	M	15850	Disposed	2026-03-14	Common Stock (15850)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	418.689	Indirect

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Phantom Stock	$		Common Stock (3395.152)	3395.152	Direct
Non-qualified Stock Option	$86.17	2027-03-12	Common Stock (17630)	17630	Direct
Non-qualified Stock Option	$127.90	2028-03-16	Common Stock (24500)	24500	Direct
Non-qualified Stock Option	$158.56	2029-03-15	Common Stock (11405)	11405	Direct
Non-qualified Stock Option	$177.09	2030-03-15	Common Stock (9452)	9452	Direct
Non-qualified Stock Option	$243.54	2031-03-01	Common Stock (10884)	10884	Direct
Non-qualified Stock Option	$337.74	2032-03-01	Common Stock (11350)	11350	Direct
Notional Stock Units	$0		Common Stock (5228.41)	5228.41	Direct

Footnotes

F1: Each share of phantom stock represents a right to receive one share of Gallagher common stock.

F2: 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 in the year they attain age 62, or after a one-year period for participants who have attained age 61.

F3: One-third of this stock option becomes exerciseable on each of the 3rd, 4th, and 5th anniversaries of the grant date.

F4: One-third of this stock option becomes exerciseable on each of the 3rd, 4th, and 5th anniversaries of the grant date.

F5: One-third of this stock option becomes exercisable on each of the 3rd, 4th, and 5th anniversaries of the grant date.

F6: Closing price of Gallagher common stock on February 28, 2025.

F7: Each notional stock unit represents a right to receive one share of Gallagher common stock.

F8: The notional stock units become payable following the reporting person's separation from service with Gallagher.