=== SEC Form 4 — Statement of Changes in Beneficial Ownership ===
Document Type: 4
Period of Report: 2026-06-22
10b5-1 Pre-arranged Plan: No
--- Issuer ---
Name: Arthur J. Gallagher & Co. (AJG)
CIK: 0000354190
--- Reporting Owner ---
Name: HOWELL DOUGLAS K
CIK: 0001222374
Role: Officer (VP & Chief Financial Officer)
--- Derivative Transactions ---
[Transaction #1]
Security: Notional Stock Units
Date: 2026-06-22 | Code: I (Discretionary (intra-plan))
Shares: -12,954.386 | Price: $209.08
Shares Owned After: 185,953.9256 | Ownership: D (Direct)
Footnotes:
[F2] Each notional stock unit represents a right to receive one share of Gallagher common stock.
[F3] This disposition of notional stock units is a discretionary transaction by the reporting person to move assets he holds in the company's Supplemental Savings and Thrift Plan ("SS&T Plan"), a nonqualified deferred compensation plan, from the investment option representing Gallagher common stock to cash partially to cover his expected tax obligations as a result of a distribution that will occur in July 2026 under such plan.
[F4] Portions of these notional stock units are payable to the reporting person in shares of common stock in July of 2026, 2028 and 2029 and following the reporting person's separation from service.
[F4] Portions of these notional stock units are payable to the reporting person in shares of common stock in July of 2026, 2028 and 2029 and following the reporting person's separation from service.
[F5] The reporting person's disposition of Gallagher common stock reported herein was matchable under Section 16(b) of the Securities and Exchange Act of 1934, to the extent of 12,892.211 shares the reporting person invested in through the SS&T Plan on February 12, 2026. The reporting person had a loss of approximately $32,123 in connection with this short-swing transaction.
--- Holdings ---
[Holding #1]
Security: Common Stock
Ownership: D (Direct)
[Holding #2]
Security: Common Stock
Ownership: I (Indirect)
Footnotes:
[F1] The reporting person has no voting or invesment power over these shares and disclaims beneficial ownership.
[Holding #3]
Security: Common Stock
Ownership: I (Indirect)
[Holding #4]
Security: Notional Stock Units
Ownership: D (Direct)
Footnotes:
[F2] Each notional stock unit represents a right to receive one share of Gallagher common stock.
[F6] The notional stock units become payable following the reporting person's separation from service with Gallagher.
[F6] The notional stock units become payable following the reporting person's separation from service with Gallagher.
[Holding #5]
Security: Non-qualified Stock Option
Ownership: D (Direct)
Footnotes:
[F7] One-third of this stock option becomes exerciseable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
[Holding #6]
Security: Non-qualified Stock Option
Ownership: D (Direct)
Footnotes:
[F8] One-third of this stock option becomes exercisable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
[Holding #7]
Security: Non-qualified Stock Option
Ownership: D (Direct)
Footnotes:
[F7] One-third of this stock option becomes exerciseable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
[Holding #8]
Security: Non-qualified Stock Option
Ownership: D (Direct)
Footnotes:
[F7] One-third of this stock option becomes exerciseable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
[Holding #9]
Security: Non-qualified Stock Option
Ownership: D (Direct)
Footnotes:
[F9] Closing price of Gallagher common stock on February 28, 2025.
[F7] One-third of this stock option becomes exerciseable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
[Holding #10]
Security: Non-qualified Stock Option
Ownership: D (Direct)
Footnotes:
[F10] One-third of this stock option becomes exercisable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
[Holding #11]
Security: Non-qualified Stock Option
Ownership: D (Direct)
Footnotes:
[F11] One-third of this stock option becomes exercisable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
[Holding #12]
Security: Phantom Stock
Ownership: D (Direct)
Footnotes:
[F12] Each share of phantom stock represents a right to receive one share of Gallagher common stock.
[F13] 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.
[F13] 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.
--- Footnotes (Complete Index) ---
F1: The reporting person has no voting or invesment power over these shares and disclaims beneficial ownership.
F10: One-third of this stock option becomes exercisable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
F11: One-third of this stock option becomes exercisable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
F12: Each share of phantom stock represents a right to receive one share of Gallagher common stock.
F13: 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.
F2: Each notional stock unit represents a right to receive one share of Gallagher common stock.
F3: This disposition of notional stock units is a discretionary transaction by the reporting person to move assets he holds in the company's Supplemental Savings and Thrift Plan ("SS&T Plan"), a nonqualified deferred compensation plan, from the investment option representing Gallagher common stock to cash partially to cover his expected tax obligations as a result of a distribution that will occur in July 2026 under such plan.
F4: Portions of these notional stock units are payable to the reporting person in shares of common stock in July of 2026, 2028 and 2029 and following the reporting person's separation from service.
F5: The reporting person's disposition of Gallagher common stock reported herein was matchable under Section 16(b) of the Securities and Exchange Act of 1934, to the extent of 12,892.211 shares the reporting person invested in through the SS&T Plan on February 12, 2026. The reporting person had a loss of approximately $32,123 in connection with this short-swing transaction.
F6: The notional stock units become payable following the reporting person's separation from service with Gallagher.
F7: One-third of this stock option becomes exerciseable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
F8: One-third of this stock option becomes exercisable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
F9: Closing price of Gallagher common stock on February 28, 2025.
--- Signature ---
/s/ /s/ Monica Norzagaray, by power of attorney (2026-06-24)
