<SEC-DOCUMENT>0001096343-17-000120.txt : 20170804
<SEC-HEADER>0001096343-17-000120.hdr.sgml : 20170804
<ACCEPTANCE-DATETIME>20170804163021
ACCESSION NUMBER:		0001096343-17-000120
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20170802
FILED AS OF DATE:		20170804
DATE AS OF CHANGE:		20170804

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Kiscaden Bradley James
		CENTRAL INDEX KEY:			0001553230

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15811
		FILM NUMBER:		171008997

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

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_150187860817190.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-08-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001553230</rptOwnerCik>
            <rptOwnerName>Kiscaden Bradley James</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>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP &amp; Chief Actuarial Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-08-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>350</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1074.56</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6816.7174</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>553.44</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 June 30, 2017 and utilizes the closing stock price on that date of $975.86 per share. As of June 30, 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 Bradley James Kiscaden</signatureName>
        <signatureDate>2017-08-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>a2017february22-confirming.htm
<DESCRIPTION>KISCADEN 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/ Bradley J. Kiscaden
                            Signature

                            Bradley J. Kiscaden
                            Printed Name


</pre>
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