<SEC-DOCUMENT>0001127602-22-009544.txt : 20220316
<SEC-HEADER>0001127602-22-009544.hdr.sgml : 20220316
<ACCEPTANCE-DATETIME>20220316203528
ACCESSION NUMBER:		0001127602-22-009544
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20220314
FILED AS OF DATE:		20220316
DATE AS OF CHANGE:		20220316

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Jain Vishal
		CENTRAL INDEX KEY:			0001812516

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09761
		FILM NUMBER:		22746425

	MAIL ADDRESS:	
		STREET 1:		2850 GOLF ROAD
		CITY:			ROLLING MEADOWS
		STATE:			IL
		ZIP:			60008

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Arthur J. Gallagher & Co.
		CENTRAL INDEX KEY:			0000354190
		STANDARD INDUSTRIAL CLASSIFICATION:	INSURANCE AGENTS BROKERS & SERVICES [6411]
		IRS NUMBER:				362151613
		STATE OF INCORPORATION:			IL
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2850 GOLF ROAD
		CITY:			ROLLING MEADOWS
		STATE:			IL
		ZIP:			60008-4050
		BUSINESS PHONE:		630-773-3800

	MAIL ADDRESS:	
		STREET 1:		2850 GOLF ROAD
		CITY:			ROLLING MEADOWS
		STATE:			IL
		ZIP:			60008-4050

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ARTHUR J. GALLAGHER & CO.
		DATE OF NAME CHANGE:	20190819

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	GALLAGHER ARTHUR J & CO
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
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        <issuerName>Arthur J. Gallagher &amp; Co.</issuerName>
        <issuerTradingSymbol>AJG</issuerTradingSymbol>
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            <rptOwnerStreet2></rptOwnerStreet2>
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            <officerTitle>VICE PRESIDENT</officerTitle>
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                <natureOfOwnership>
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                </natureOfOwnership>
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        </nonDerivativeHolding>
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    <derivativeTable>
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                <underlyingSecurityTitle>
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        <derivativeTransaction>
            <securityTitle>
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    <footnotes>
        <footnote id="F1">Performance share units (awarded on March 14, 2019) earned and vested as of March 14, 2022.</footnote>
        <footnote id="F2">One-third of this stock option becomes exerciseable on each of the 3rd, 4th, and 5th anniversaries of the grant date.</footnote>
        <footnote id="F3">Each share of phantom stock represents a right to receive one share of Gallagher common stock.</footnote>
        <footnote id="F4">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.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Seth Diehl, by power of attorney</signatureName>
        <signatureDate>2022-03-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
