<SEC-DOCUMENT>0001096343-16-000296.txt : 20160519
<SEC-HEADER>0001096343-16-000296.hdr.sgml : 20160519
<ACCEPTANCE-DATETIME>20160519163225
ACCESSION NUMBER:		0001096343-16-000296
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20160518
FILED AS OF DATE:		20160519
DATE AS OF CHANGE:		20160519

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MARKEL CORP
		CENTRAL INDEX KEY:			0001096343
		STANDARD INDUSTRIAL CLASSIFICATION:	FIRE, MARINE & CASUALTY INSURANCE [6331]
		IRS NUMBER:				541959284
		STATE OF INCORPORATION:			VA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4521 HIGHWOODS PARKWAY
		CITY:			GLEN ALLEN
		STATE:			VA
		ZIP:			23060-3382
		BUSINESS PHONE:		8047470136

	MAIL ADDRESS:	
		STREET 1:		4521 HIGHWOODS PKWY
		CITY:			GLEN ALLEN
		STATE:			VA
		ZIP:			23060

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MARKEL HOLDINGS INC
		DATE OF NAME CHANGE:	19991005

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Crowley F. Michael
		CENTRAL INDEX KEY:			0001304761

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15811
		FILM NUMBER:		161663555

	MAIL ADDRESS:	
		STREET 1:		C/O MARKEL CORPORATION
		STREET 2:		4521 HIGHWOODS PARKWAY
		CITY:			GLEN ALLEN
		STATE:			VA
		ZIP:			23060

	FORMER NAME:	
		FORMER CONFORMED NAME:	Crowley Michael F
		DATE OF NAME CHANGE:	20040930
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_146368993232577.xml
<DESCRIPTION>FORM 4
<TEXT>
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    <periodOfReport>2016-05-18</periodOfReport>

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    <issuer>
        <issuerCik>0001096343</issuerCik>
        <issuerName>MARKEL CORP</issuerName>
        <issuerTradingSymbol>MKL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001304761</rptOwnerCik>
            <rptOwnerName>Crowley F. Michael</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MARKEL CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>4521 HIGHWOODS PARKWAY</rptOwnerStreet2>
            <rptOwnerCity>GLEN ALLEN</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>23060</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
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                <value>Common Stock</value>
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            <transactionDate>
                <value>2016-05-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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                <transactionCode>S</transactionCode>
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            <transactionAmounts>
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                <transactionPricePerShare>
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                <transactionCode>S</transactionCode>
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        </nonDerivativeTransaction>
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                <transactionPricePerShare>
                    <value>950.95</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
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            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9225</value>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
                <value>2016-05-18</value>
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                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>348</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>951.55</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8877</value>
                </sharesOwnedFollowingTransaction>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
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            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>300</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>951.84</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8577</value>
                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
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            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>200</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>952.033</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8377</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>101.422</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>401(K) Plan</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Holdings under the Markel Corporation 401(K) Plan are reported in units.  The information reported herein is based on a plan statement dated as of March 31, 2016 and utilizes the closing stock price on that date of $891.57 per share.  As of March 31, 2016, a unit under the Plan represented one share of Common Stock.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Donna L. Strauss, Attorney-in-fact for F. Michael Crowley</signatureName>
        <signatureDate>2016-05-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
