<SEC-DOCUMENT>0001552961-12-000003.txt : 20120626
<SEC-HEADER>0001552961-12-000003.hdr.sgml : 20120626
<ACCEPTANCE-DATETIME>20120626095114
ACCESSION NUMBER:		0001552961-12-000003
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20120614
FILED AS OF DATE:		20120626
DATE AS OF CHANGE:		20120626

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BOSCO HARRY L
		CENTRAL INDEX KEY:			0001185881

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35083
		FILM NUMBER:		12926320

	MAIL ADDRESS:	
		STREET 1:		C/O ARRIS GROUP INC
		STREET 2:		11450 TECHNOLOGY CIRCLE
		CITY:			DULUTH
		STATE:			GA
		ZIP:			30097

ISSUER:		

	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

	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
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0205</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2012-06-14</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001076930</issuerCik>
        <issuerName>GSI GROUP INC</issuerName>
        <issuerTradingSymbol>GSIG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001185881</rptOwnerCik>
            <rptOwnerName>BOSCO HARRY L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>GSI GROUP INC</rptOwnerStreet1>
            <rptOwnerStreet2>125 MIDDLESEX TURNPIKE</rptOwnerStreet2>
            <rptOwnerCity>BEDFORD</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01730</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <ownerSignature>
        <signatureName>Paula A Pluta, Attorney-in-Fact</signatureName>
        <signatureDate>2012-06-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
