<SEC-DOCUMENT>0001288469-19-000136.txt : 20190822
<SEC-HEADER>0001288469-19-000136.hdr.sgml : 20190822
<ACCEPTANCE-DATETIME>20190822195416
ACCESSION NUMBER:		0001288469-19-000136
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20190820
FILED AS OF DATE:		20190822
DATE AS OF CHANGE:		20190822

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			REDDY MADHUKAR
		CENTRAL INDEX KEY:			0001478343

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34666
		FILM NUMBER:		191046946

	MAIL ADDRESS:	
		STREET 1:		2051 PALOMAR AIRPORT RD, SUITE 100
		CITY:			CARLSBAD
		STATE:			CA
		ZIP:			92011

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MAXLINEAR INC
		CENTRAL INDEX KEY:			0001288469
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				141896129
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		5966 LA PLACE CT.
		CITY:			CARLSBAD
		STATE:			CA
		ZIP:			92008
		BUSINESS PHONE:		760-692-0711

	MAIL ADDRESS:	
		STREET 1:		5966 LA PLACE CT.
		CITY:			CARLSBAD
		STATE:			CA
		ZIP:			92008
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_156651803881166.xml
<DESCRIPTION>FORM 4
<TEXT>
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    <periodOfReport>2019-08-20</periodOfReport>

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    <issuer>
        <issuerCik>0001288469</issuerCik>
        <issuerName>MAXLINEAR INC</issuerName>
        <issuerTradingSymbol>MXL</issuerTradingSymbol>
    </issuer>

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        <reportingOwnerId>
            <rptOwnerCik>0001478343</rptOwnerCik>
            <rptOwnerName>REDDY MADHUKAR</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MAXLINEAR, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>5966 LA PLACE COURT, SUITE 100</rptOwnerStreet2>
            <rptOwnerCity>CARLSBAD</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92008</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, Central Engineering</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2019-08-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>10326</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
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                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
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                    <value>354326</value>
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                    <value>D</value>
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                <value>Common Stock</value>
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                    <value>20.66</value>
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            </transactionAmounts>
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                <sharesOwnedFollowingTransaction>
                    <value>344000</value>
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                    <value>D</value>
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                <value>Common Stock</value>
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                <sharesOwnedFollowingTransaction>
                    <value>29269</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
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                <natureOfOwnership>
                    <value>See footnote</value>
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            <securityTitle>
                <value>Common Stock</value>
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                    <value>29269</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F3"/>
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            </ownershipNature>
        </nonDerivativeHolding>
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    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
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            <transactionDate>
                <value>2019-08-20</value>
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            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>1575</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1575.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3178</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
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            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
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            <transactionDate>
                <value>2019-08-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7824</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F5"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>7824.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>21042</value>
                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
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            <transactionDate>
                <value>2019-08-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>927</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F6"/>
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            <expirationDate>
                <footnoteId id="F6"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>927.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11219</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each restricted stock unit (&quot;RSU&quot;) represents a contingent right to receive one share of MaxLinear, Inc. Common Stock.</footnote>
        <footnote id="F2">Shares held by Madhukar Reddy Cust Anavi Maram Reddy UTMA, for which the Reporting Person serves as custodian.</footnote>
        <footnote id="F3">Shares held by Madhukar Reddy Cust Arnav Maram Reddy UTMA, for which the Reporting Person serves as custodian.</footnote>
        <footnote id="F4">Subject to the Reporting Person's continuing to be a Service Provider (as defined in the 2010 Equity Incentive Plan) through each applicable vesting date, one-sixteenth (1/16th) of the 50,835 RSUs subject to the award shall vest on February 20, 2016, and an additional one-sixteenth (1/16th) of the RSUs subject to the award shall vest on each successive May 20, August 20, November 20, and February 20 thereafter, such that the award will be fully vested on November 20, 2019.</footnote>
        <footnote id="F5">Subject to the Reporting Person's continuing to be a Service Provider (as defined in the 2010 Equity Incentive Plan) through each applicable vesting date, ten percent (10%) of the 52,606 RSUs subject to the award shall vest on August 20, 2017; twenty percent (20%) of the RSUs subject to the award shall vest on August 20, 2018; thirty (30%) of the RSUs subject to the award shall vest on August 20, 2019; and forty (40%) of the RSUs subject to the award shall vest on August 20, 2020.</footnote>
        <footnote id="F6">Subject to the Reporting Person's continuing to be a Service Provider (as defined in the 2010 Equity Incentive Plan) through each applicable vesting date, one-sixteenth (1/16th) of the 29,917 RSUs subject to the award shall vest on May 20, 2017, and an additional one-sixteenth (1/16th) of the RSUs subject to the award shall vest on each successive August 20, November 20, February 20 and May 20 thereafter, such that the award will be fully vested on February 20, 2021.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Connie Kwong, as Attorney-in-Fact</signatureName>
        <signatureDate>2019-08-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
