<SEC-DOCUMENT>0001096343-17-000115.txt : 20170803
<SEC-HEADER>0001096343-17-000115.hdr.sgml : 20170803
<ACCEPTANCE-DATETIME>20170803164704
ACCESSION NUMBER:		0001096343-17-000115
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20170801
FILED AS OF DATE:		20170803
DATE AS OF CHANGE:		20170803

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MARKEL STEVEN A
		CENTRAL INDEX KEY:			0001184575

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15811
		FILM NUMBER:		171005711

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
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_150179321111637.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-08-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001184575</rptOwnerCik>
            <rptOwnerName>MARKEL STEVEN A</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>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice Chairman</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-08-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3875</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1074.4825</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>109650</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Spouse</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2027.222</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>401(K) Plan</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Mr. Markel is trustee and retains a partial interest in the trust.  The amount reported reflects all the securities held by the trust, but Mr. Markel disclaims beneficial ownership except with respect to his interest in the trust.</footnote>
        <footnote id="F2">Beneficial ownership of securities is expressly disclaimed.</footnote>
        <footnote id="F3">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, 2017 and utilizes the closing stock price on that date of $975.86 per share. As of March 31, 2017, 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 Steven A. Markel</signatureName>
        <signatureDate>2017-08-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>a2017february22-confirming.htm
<DESCRIPTION>MARKEL, STEVEN POA 02222017
<TEXT>
<!-- Document created using Workiva -->
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<pre>
CONFIRMING STATEMENT


    This Statement confirms that the undersigned has authorized and designated Richard R.
Grinnan, Anne G. Waleski, Karl M. Strait, Anna M. King, Alex K. Tinucci or Donna L. Strauss
(each an "Authorized Signer") to execute and file (in any permitted format) on the undersigned's
behalf all Forms 3, 4 and 5 (including any amendments thereto) and Form 144s that the
undersigned may be required to file with the United States Securities and Exchange Commission
as a result of the undersigned's ownership of, or transactions in, securities of Markel Corporation.
Any such previous authorization is hereby revoked.  Each Authorized Signer is authorized to
obtain CIK and EDGAR access codes and take all such other actions as may be necessary or
desirable to permit electronic filings of such forms.  The authority of each Authorized Signer
under this Statement shall continue until the undersigned is no longer required to file Forms 3, 4
or 5 or Form 144s with regard to the undersigned's ownership of, or transactions in, securities of
Markel Corporation, unless earlier revoked in writing.  The undersigned acknowledges that none
of the Authorized Signers or Markel Corporation is assuming any of the undersigned's
responsibilities to comply with Section 16 of the Securities Exchange Act of 1934 or Rule 144.

Date:  February 22, 2017


                            /s/ Steven A. Markel
                            Signature

                            Steven A. Markel
                            Printed Name


</pre>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
