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    ACCESSION NUMBER:		0000040211-20-000026
    CONFORMED SUBMISSION TYPE:	10-K/A
    PUBLIC DOCUMENT COUNT:		66
    CONFORMED PERIOD OF REPORT:	20191231
    FILED AS OF DATE:		20200330
    DATE AS OF CHANGE:		20200330

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			GATX CORP
    		CENTRAL INDEX KEY:			0000040211
    		STANDARD INDUSTRIAL CLASSIFICATION:	TRANSPORTATION SERVICES [4700]
    		IRS NUMBER:				361124040
    		STATE OF INCORPORATION:			NY
    		FISCAL YEAR END:			1231

    	FILING VALUES:
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    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-02328
    		FILM NUMBER:		20757301

    	BUSINESS ADDRESS:
    		STREET 1:		233 SOUTH WACKER DRIVE
    		CITY:			CHICAGO
    		STATE:			IL
    		ZIP:			60606-7147
    		BUSINESS PHONE:		3126216200

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    		CITY:			CHICAGO
    		STATE:			IL
    		ZIP:			60606-7147

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	GENERAL AMERICAN TRANSPORTATION CORP
    		DATE OF NAME CHANGE:	19750722
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