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<ACCEPTANCE-DATETIME>20210520162002
ACCESSION NUMBER:		0001193125-21-167806
CONFORMED SUBMISSION TYPE:	8-K
PUBLIC DOCUMENT COUNT:		17
CONFORMED PERIOD OF REPORT:	20210520
ITEM INFORMATION:		Other Events
ITEM INFORMATION:		Financial Statements and Exhibits
FILED AS OF DATE:		20210520
DATE AS OF CHANGE:		20210520

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

	FILING VALUES:
		FORM TYPE:		8-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09761
		FILM NUMBER:		21944772

	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
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