<SEC-DOCUMENT>0000855658-19-000100.txt : 20190910
<SEC-HEADER>0000855658-19-000100.hdr.sgml : 20190910
<ACCEPTANCE-DATETIME>20190910125936
ACCESSION NUMBER:		0000855658-19-000100
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20190906
FILED AS OF DATE:		20190910
DATE AS OF CHANGE:		20190910

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ANDERSON JAMES ROBERT
		CENTRAL INDEX KEY:			0001644651

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-18032
		FILM NUMBER:		191084778

	MAIL ADDRESS:	
		STREET 1:		111 SW 5TH AVE
		CITY:			PORTLNAD
		STATE:			OR
		ZIP:			97204

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LATTICE SEMICONDUCTOR CORP
		CENTRAL INDEX KEY:			0000855658
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				930835214
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0102

	BUSINESS ADDRESS:	
		STREET 1:		111 SW 5TH AVE., SUITE 700
		CITY:			PORTLAND
		STATE:			OR
		ZIP:			97204
		BUSINESS PHONE:		5032688000

	MAIL ADDRESS:	
		STREET 1:		111 SW 5TH AVE., SUITE 700
		CITY:			PORTLAND
		STATE:			OR
		ZIP:			97204
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-09-06</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000855658</issuerCik>
        <issuerName>LATTICE SEMICONDUCTOR CORP</issuerName>
        <issuerTradingSymbol>LSCC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001644651</rptOwnerCik>
            <rptOwnerName>ANDERSON JAMES ROBERT</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>111 SW 5TH AVE., 7TH FL.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PORTLAND</rptOwnerCity>
            <rptOwnerState>OR</rptOwnerState>
            <rptOwnerZipCode>97204</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President &amp; CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-09-06</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>181478</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.0</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>262788</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-09-06</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F3"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>89977</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.98</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>172811</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares earned with respect to performance restricted stock units (PRSUs)based on the achievement by Lattice Semiconductor of certain performance targets for the period September 4, 2018 to September 3, 2019.</footnote>
        <footnote id="F2">Restricted Stock Units - no purchase price for this transaction.</footnote>
        <footnote id="F3">These shares were retained by the Issuer in order to meet the tax withholding obligations of the Reporting Person in connection with the vesting of an installment of the restricted stock units.  The amount retained by the Issuer was not in excess of the amount of the tax liability.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: Byron W. Milstead, Attorney-in-Fact For: James R. Anderson</signatureName>
        <signatureDate>2019-09-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
