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    CONFORMED SUBMISSION TYPE:	DEF 14A
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    FILED AS OF DATE:		20230327
    DATE AS OF CHANGE:		20230327

    FILER:

    	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

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    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-09761
    		FILM NUMBER:		23761360

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

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    		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
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