<SEC-DOCUMENT>0001096343-18-000110.txt : 20180516
<SEC-HEADER>0001096343-18-000110.hdr.sgml : 20180516
<ACCEPTANCE-DATETIME>20180516175609
ACCESSION NUMBER:		0001096343-18-000110
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20180514
FILED AS OF DATE:		20180516
DATE AS OF CHANGE:		20180516

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MARTIN DARRELL D
		CENTRAL INDEX KEY:			0001184576

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15811
		FILM NUMBER:		18841168

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:			23060-6148
		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_152650775547318.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-05-14</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001184576</rptOwnerCik>
            <rptOwnerName>MARTIN DARRELL D</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MARKEL CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>4521 HIGHWOODS PKWY</rptOwnerStreet2>
            <rptOwnerCity>GLEN ALLEN</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>23060</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-05-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>110</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12188</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6900</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Spouse</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Restricted stock granted pursuant to the Markel Corporation 2016 Equity Incentive Compensation Plan. Shares will vest May 14, 2019.</footnote>
        <footnote id="F2">Beneficial ownership of securities is expressly disclaimed.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Karl M. Strait, Attorney-in-fact for Darrell D. Martin</signatureName>
        <signatureDate>2018-05-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>a2018february22-confirming.htm
<DESCRIPTION>2018 - MARTIN POA 02222018
<TEXT>
<!-- Document created using Workiva -->
<html>
<body>
<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, Brian D. Sorkin or Donna S.
Donavant (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 Forms 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, 2018


                            /s/ Darrell D. Martin
                            Signature

                            Darrell D. Martin
                            Printed Name


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