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    ACCESSION NUMBER:		0001193125-15-081547
    CONFORMED SUBMISSION TYPE:	S-3
    PUBLIC DOCUMENT COUNT:		22
    FILED AS OF DATE:		20150309
    DATE AS OF CHANGE:		20150306

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			GSI GROUP INC
    		CENTRAL INDEX KEY:			0001076930
    		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS ELECTRICAL MACHINERY, EQUIPMENT & SUPPLIES [3690]
    		IRS NUMBER:				980110412
    		STATE OF INCORPORATION:			A3
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		S-3
    		SEC ACT:		1933 Act
    		SEC FILE NUMBER:	333-202597
    		FILM NUMBER:		15683295

    	BUSINESS ADDRESS:
    		STREET 1:		125 MIDDLESEX TURNPIKE
    		STREET 2:		.
    		CITY:			BEDFORD
    		STATE:			MA
    		ZIP:			01730
    		BUSINESS PHONE:		781-266-5618

    	MAIL ADDRESS:
    		STREET 1:		125 MIDDLESEX TURNPIKE
    		STREET 2:		.
    		CITY:			BEDFORD
    		STATE:			MA
    		ZIP:			01730

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	GSI LUMONICS INC
    		DATE OF NAME CHANGE:	19990401

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	GSI LUMONICS
    		DATE OF NAME CHANGE:	19990331

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	LUMONICS INC
    		DATE OF NAME CHANGE:	19990115
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