<SEC-DOCUMENT>0001628280-18-011661.txt : 20180906
<SEC-HEADER>0001628280-18-011661.hdr.sgml : 20180906
<ACCEPTANCE-DATETIME>20180906163931
ACCESSION NUMBER:		0001628280-18-011661
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180904
FILED AS OF DATE:		20180906
DATE AS OF CHANGE:		20180906

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Lorig Brian
		CENTRAL INDEX KEY:			0001697041

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-09992
		FILM NUMBER:		181057952

	MAIL ADDRESS:	
		STREET 1:		ONE TECHNOLOGY DRIVE
		CITY:			MILPITAS
		STATE:			X1
		ZIP:			95035

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_153626635264902.xml
<DESCRIPTION>FORM 4
<TEXT>
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            <isTenPercentOwner>0</isTenPercentOwner>
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            <officerTitle>SVP</officerTitle>
            <otherText></otherText>
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            <securityTitle>
                <value>Common Stock</value>
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                    <value>117.46</value>
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    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Each restricted stock unit (&quot;RSU&quot;) represents a contingent right to receive one share of KLA-Tencor common stock.</footnote>
        <footnote id="F2">On September 4, 2014, the Reporting Person was granted an RSU for 2,200 shares of KLA-Tencor Common Stock. On September 4, 2018, 25% of those shares vested.</footnote>
        <footnote id="F3">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>
        <footnote id="F4">Pursuant to the terms of the grant, shares of KLA-Tencor common stock were automatically withheld at vesting to cover required tax withholding. The fair market value of KLA-Tencor common stock used for purposes of calculating the number of shares to be withheld was the closing price of KLA-Tencor common stock as reported on September 4, 2018.</footnote>
        <footnote id="F5">On September 4, 2014, in addition to the RSUs granted on that date that were subject only to service-vesting requirements (which RSUs were previously reported on Form 4), the Reporting Person was also granted RSUs covering up to a maximum of 2,750 shares (based on 125% of the target shares of 2,200) of KLA-Tencor common stock, subject to both performance-vesting and service-vesting requirements. On September 4, 2018, 50% of the RSUs vested.</footnote>
        <footnote id="F6">This sale was effected pursuant to the terms of a Rule 10b5-1 trading plan adopted by the Reporting Person on January 30, 2018.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Teri A. Little, attorney-in-fact for Brian Lorig</signatureName>
        <signatureDate>2018-09-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
