<SEC-DOCUMENT>0001096343-18-000074.txt : 20180326
<SEC-HEADER>0001096343-18-000074.hdr.sgml : 20180326
<ACCEPTANCE-DATETIME>20180326163230
ACCESSION NUMBER:		0001096343-18-000074
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20180320
FILED AS OF DATE:		20180326
DATE AS OF CHANGE:		20180326

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MARKEL ANTHONY F
		CENTRAL INDEX KEY:			0001096933
		STATE OF INCORPORATION:			VA

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15811
		FILM NUMBER:		18713074

	MAIL ADDRESS:	
		STREET 1:		4551 COX RD
		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_152209633739292.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-03-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001096933</rptOwnerCik>
            <rptOwnerName>MARKEL ANTHONY F</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>2018-03-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value>E</value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>225</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>37461</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>40237</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6220</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>As Trustee</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3366</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>As Trustee</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2850</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>As Trustee</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2669</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>As Trustee</value>
                    <footnoteId id="F5"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2443</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1961</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>As Trustee</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The total reported for Grantor Retained Annuity Trusts (as well as the direct holding balance of Mr. Markel) also reflects the distribution of 269 shares from Grantor Retained Annuity Trusts to Mr. Markel.</footnote>
        <footnote id="F2">Mr. Markel is a Trustee and partial beneficiary of several Grantor Retained Annuity Trusts.  The total reported represents the aggregate of the trusts.</footnote>
        <footnote id="F3">Mr. Markel is the Trustee under trusts for the benefit of himself and his children.</footnote>
        <footnote id="F4">Mr. Markel is the Trustee of irrevocable trusts for the benefit of his children. Beneficial ownership of securities is expressly disclaimed.</footnote>
        <footnote id="F5">Mr. Markel is the Trustee under a charitable lead unitrust in which his children have remainder interests. Beneficial ownership of securities is expressly disclaimed.</footnote>
        <footnote id="F6">Mr. Markel is the Trustee of a trust for the benefit of his children and their descendants and in which Mr. Markel retains a partial interest. Mr. Markel disclaims beneficial ownership of the shares held in the trust except to the extent of his partial interest.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Donna S. Donavant, Attorney-in-fact for Anthony F. Markel</signatureName>
        <signatureDate>2018-03-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>a2018february22-confirming.htm
<DESCRIPTION>2018 - MARKEL, ANTHONY 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 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, 2018


                            /s/ Anthony F. Markel
                            Signature

                            Anthony F. Markel
                            Printed Name
</pre>
</body>
</html>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
