<SEC-DOCUMENT>0001628280-17-008381.txt : 20170808
<SEC-HEADER>0001628280-17-008381.hdr.sgml : 20170808
<ACCEPTANCE-DATETIME>20170808200830
ACCESSION NUMBER:		0001628280-17-008381
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170804
FILED AS OF DATE:		20170808
DATE AS OF CHANGE:		20170808

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Kirloskar Virendra A
		CENTRAL INDEX KEY:			0001430600

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-09992
		FILM NUMBER:		171016170

	MAIL ADDRESS:	
		STREET 1:		160 RIO ROBLES
		CITY:			SAN JOSE
		STATE:			CA
		ZIP:			95134

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			KLA TENCOR CORP
		CENTRAL INDEX KEY:			0000319201
		STANDARD INDUSTRIAL CLASSIFICATION:	OPTICAL INSTRUMENTS & LENSES [3827]
		IRS NUMBER:				042564110
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		ONE TECHNOLOGY DRIVE
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035
		BUSINESS PHONE:		4088756000

	MAIL ADDRESS:	
		STREET 1:		ONE TECHNOLOGY DRIVE
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	KLA INSTRUMENTS CORP
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_150223729565146.xml
<DESCRIPTION>FORM 4
<TEXT>
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            <rptOwnerStreet1>C/O KLA-TENCOR CORPORATION</rptOwnerStreet1>
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            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95035</rptOwnerZipCode>
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            <isDirector>0</isDirector>
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            <isTenPercentOwner>0</isTenPercentOwner>
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            <officerTitle>SVP &amp; Chief Accounting Officer</officerTitle>
            <otherText></otherText>
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                    <value>89.15</value>
                </transactionPricePerShare>
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                    <value>D</value>
                </directOrIndirectOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock - Restricted Stock Units</value>
                <footnoteId id="F8"/>
            </securityTitle>
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                <sharesOwnedFollowingTransaction>
                    <value>15808</value>
                    <footnoteId id="F9"/>
                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
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    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">On August 4, 2016, the Reporting Person received a grant of RSUs covering 6,900 shares of KLA-Tencor common stock. On August 4, 2017, the Reporting Person vested in 25% of such RSUs.</footnote>
        <footnote id="F2">Pursuant to such terms of the August 4, 2016 RSU grant, 649 shares of KLA-Tencor common stock were automatically withheld at vesting to cover required tax withholding.</footnote>
        <footnote id="F3">On August 6, 2013, August 6, 2013, August 6, 2013 and August 6, 2015, the Reporting Person received a grant of RSUs or PRSUs covering 4,050 (RSU), 4,050 (PRSU), 8,000 (RSU) and 4,400 (RSU) shares of KLA-Tencor common stock, respectively. On August 6, 2017, the Reporting Person vested in 25%, 50%, 50% and 25% of such RSUs and PRSUs, respectively.</footnote>
        <footnote id="F4">Pursuant to such terms of the August 6, 2013, August 6, 2013, August 6, 2013 and August 6, 2015 grants, 3,412 shares of KLA-Tencor common stock were automatically withheld at vesting to cover required tax withholding.</footnote>
        <footnote id="F5">On August 7, 2014, the Reporting Person received a grant of RSUs covering 3,650 shares of KLA-Tencor common stock. On August 7, 2017, the Reporting Person vested in 25% of such RSUs.</footnote>
        <footnote id="F6">Pursuant to such terms of the August 7, 2014 RSU grant, 476 shares of KLA-Tencor common stock were automatically withheld at vesting to cover required tax withholding.</footnote>
        <footnote id="F7">This sale was effected pursuant to the terms of a Rule 10b5-1 trading plan adopted by the Reporting Person on November 25, 2016.</footnote>
        <footnote id="F8">Each RSU represents a contingent right to receive one share of KLA-Tencor common stock.</footnote>
        <footnote id="F9">Does not include performance-based RSUs, if any, held by the Reporting Person for which an assessment has not yet been made regarding the achievement of the applicable performance goals.  Any such holdings will be reported on a Form 4 within two business days of the date such assessment is made.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Teri Little as Attorney-in-Fact for Virendra A. Kirloskar</signatureName>
        <signatureDate>2017-08-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
