BAY WALTER D. (General Counsel) exercised options at ARTHUR J. GALLAGHER & CO.

Option exercise — a mechanical event triggered by vesting or expiry. Not a discretionary conviction trade.

M · 1 exercise

BAY WALTER D.

Filed: 4/1/2026ACC: 0000354190-26-000114

InsiderBAY WALTER D.CIK 1410235

→

IssuerARTHUR J. GALLAGHER & CO.CIK 354190

Officer· General Counsel

Since Mar 2026

-627.00

Net shares

Net seller

$135.4K

Total sold

Open market trades

0B · 0S

Total transactions

1.42K acquired · 2.04K disposed

Non-Derivative Transactions2

Common Stock

Direct

M · Option Exercise

+1.42K

Price / share

$215.95

Trade value

$305.59K

% of position

1.7%

3/31/2026

82.50K→83.92K

Common Stock

Direct

F · Tax Withholding

−627.00

Price / share

$215.95

Trade value

$135.40K

% of position

0.7%

3/31/2026

83.92K→83.29K

Total

Net shares

+788.09

Net value

$170.19K

Security	Date	Type	Shares	Price / Share	Trade Value	% of Position	Held Before	Held After
Common Stock Direct	3/31/2026	M · Option Exercise	+1.42K	$215.95	$305.59K	1.7%	82.50K	83.92K
Common Stock Direct	3/31/2026	F · Tax Withholding	−627.00	$215.95	$135.40K	0.7%	83.92K	83.29K
Total			+788.09		$170.19K

Derivative Transactions1

Phantom Stock

Direct

M · Option Exercise

Converts to

Common Stock

1.42K shares

−1.42K

Strike price

Held after

3.99K

Exercisable

—

3/31/2026

Security	Converts To	Date	Type	Shares	Strike Price	Exercisable	Held After
Phantom Stock Direct	Common Stock1.42K shares	3/31/2026	M · Option Exercise	−1.42K		—	3.99K

Non-Derivative Holdings (Post-Transaction)1

Common Stock

Indirect

Shares owned491.13

Total

491.13 indirect491.13

Security Title	Shares Owned	Ownership Type
Common Stock	491.13	Indirect
Total	491.13	491.13 indirect

Derivative Holdings (Post-Transaction)8

Non-qualified Stock Option

Direct

Underlying security

Common Stock

Underlying shares

10.88K

Shares owned

10.88K

Exercise price

243.54

Expiration

—

Exercise window

—

Notional Stock Units

Direct

Underlying security

Common Stock

Underlying shares

5.83K

Shares owned

5.83K

Exercise price

Expiration

—

Exercise window

—

Non-qualified Stock Option

Direct

Underlying security

Common Stock

Underlying shares

16.95K

Shares owned

16.95K

Exercise price

228.20

Expiration

—

Exercise window

—

Non-qualified Stock Option

Direct

Underlying security

Common Stock

Underlying shares

11.40K

Shares owned

11.40K

Exercise price

158.56

Expiration

—

Exercise window

—

Non-qualified Stock Option

Direct

Underlying security

Common Stock

Underlying shares

24.50K

Shares owned

24.50K

Exercise price

127.90

Expiration

—

Exercise window

—

Non-qualified Stock Option

Direct

Underlying security

Common Stock

Underlying shares

17.63K

Shares owned

17.63K

Exercise price

86.17

Expiration

—

Exercise window

—

Non-qualified Stock Option

Direct

Underlying security

Common Stock

Underlying shares

11.35K

Shares owned

11.35K

Exercise price

337.74

Expiration

—

Exercise window

—

Non-qualified Stock Option

Direct

Underlying security

Common Stock

Underlying shares

9.45K

Shares owned

9.45K

Exercise price

177.09

Expiration

—

Exercise window

—

Total

Underlying

108K

Owned

108K

Security	Underlying	Exercise Price	Exercise Window	Expiration	Underlying Shares	Shares Owned
Non-qualified Stock Option Direct	Common Stock	243.54	—	—	10.88K	10.88K
Notional Stock Units Direct	Common Stock	0	—	—	5.83K	5.83K
Non-qualified Stock Option Direct	Common Stock	228.20	—	—	16.95K	16.95K
Non-qualified Stock Option Direct	Common Stock	158.56	—	—	11.40K	11.40K
Non-qualified Stock Option Direct	Common Stock	127.90	—	—	24.50K	24.50K
Non-qualified Stock Option Direct	Common Stock	86.17	—	—	17.63K	17.63K
Non-qualified Stock Option Direct	Common Stock	337.74	—	—	11.35K	11.35K
Non-qualified Stock Option Direct	Common Stock	177.09	—	—	9.45K	9.45K
Total					108K	108K