<SEC-DOCUMENT>0000707549-19-000039.txt : 20190305
<SEC-HEADER>0000707549-19-000039.hdr.sgml : 20190305
<ACCEPTANCE-DATETIME>20190305170620
ACCESSION NUMBER:		0000707549-19-000039
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20190301
FILED AS OF DATE:		20190305
DATE AS OF CHANGE:		20190305

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			O'Dowd Sarah A
		CENTRAL INDEX KEY:			0001447149

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-12933
		FILM NUMBER:		19659441

	MAIL ADDRESS:	
		STREET 1:		4650 CUSHING PARKWAY
		CITY:			FREMONT
		STATE:			CA
		ZIP:			94538

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LAM RESEARCH CORP
		CENTRAL INDEX KEY:			0000707549
		STANDARD INDUSTRIAL CLASSIFICATION:	SPECIAL INDUSTRY MACHINERY, NEC [3559]
		IRS NUMBER:				942634797
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0625

	BUSINESS ADDRESS:	
		STREET 1:		4650 CUSHING BLVD
		CITY:			FREMONT
		STATE:			CA
		ZIP:			94538
		BUSINESS PHONE:		5106590200

	MAIL ADDRESS:	
		STREET 1:		4650 CUSHING PARKWAY
		CITY:			FREMONT
		STATE:			CA
		ZIP:			94538
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
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        <issuerName>LAM RESEARCH CORP</issuerName>
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            <rptOwnerName>O'Dowd Sarah A</rptOwnerName>
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            <officerTitle>Chief Legal Officer &amp; SVP</officerTitle>
            <otherText></otherText>
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                <value>0.0</value>
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            <transactionDate>
                <value>2019-03-01</value>
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                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>3717</value>
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                <transactionPricePerShare>
                    <value>0</value>
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                <transactionAcquiredDisposedCode>
                    <value>A</value>
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                <underlyingSecurityTitle>
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                    <value>3717</value>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (Right to Buy)</value>
            </securityTitle>
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                <value>176.75</value>
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                <value>2019-03-01</value>
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                    <value>176.75</value>
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            <exerciseDate>
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            <expirationDate>
                <value>2026-03-01</value>
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    <footnotes>
        <footnote id="F1">Amount reported includes shares subject to unvested Restricted Stock Units.</footnote>
        <footnote id="F2">The Restricted Stock Units will vest in three equal installments on 03/01/2020, 03/01/2021, and 03/01/2022.</footnote>
        <footnote id="F3">These Market-based Performance Restricted Stock Units vest between 0% and 150% on 03/01/2022. The performance of this award is based on the Lam Research Total Shareholder Return performance relative to the Philadelphia Semiconductor Sector Index Total Shareholder Return during the performance period of 02/01/2019 through 01/31/2022.</footnote>
        <footnote id="F4">The stock option becomes exercisable in three equal installments on 03/01/2020, 03/01/2021, and 03/01/2022.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Leign Cramer by Power of Attorney</signatureName>
        <signatureDate>2019-03-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
