-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 O8+oFnnQnajlsOw+H+QEibdmLmiqgB5XnTSyjrIWeckiPUGUQ2JT6qvTGEMCF0QQ
 MXdDOUEn5LP4ccPKLncnCg==

<SEC-DOCUMENT>0001179110-03-005929.txt : 20030819
<SEC-HEADER>0001179110-03-005929.hdr.sgml : 20030819
<ACCEPTANCE-DATETIME>20030819175544
ACCESSION NUMBER:		0001179110-03-005929
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030818
FILED AS OF DATE:		20030819

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DENNEY ARTHUR J
		CENTRAL INDEX KEY:			0001235071

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14841
		FILM NUMBER:		03856692

	BUSINESS ADDRESS:	
		STREET 1:		155 INVERNESS DRIVE
		CITY:			ENGLEWOOD
		STATE:			CO
		ZIP:			80112-5004

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MARKWEST HYDROCARBON INC
		CENTRAL INDEX KEY:			0001019756
		STANDARD INDUSTRIAL CLASSIFICATION:	NATURAL GAS DISTRIBUTION [4924]
		IRS NUMBER:				841352233
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		155 INVERNESS DRIVE WEST
		STREET 2:		SUITE 200
		CITY:			ENGLEWOOD
		STATE:			CO
		ZIP:			80112-5004
		BUSINESS PHONE:		3032908700

	MAIL ADDRESS:	
		STREET 1:		155 INVERNESS DRIVE WEST
		STREET 2:		SUITE 200
		CITY:			ENGLEWOOD
		STATE:			CO
		ZIP:			80112-5004
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>
<periodOfReport>2003-08-18</periodOfReport>
<notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0001019756</issuerCik>
        <issuerName>MARKWEST HYDROCARBON INC</issuerName>
        <issuerTradingSymbol>MWP</issuerTradingSymbol>
</issuer>
<reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001235071</rptOwnerCik>
            <rptOwnerName>DENNEY ARTHUR J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>155 INVERNESS DRIVE WEST, SUITE 200</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ENGLEWOOD</rptOwnerCity>
            <rptOwnerState>CO</rptOwnerState>
            <rptOwnerZipCode>80112</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>1</isDirector>
<isOfficer>1</isOfficer>
<isTenPercentOwner>0</isTenPercentOwner>
<isOther>0</isOther>
<officerTitle>Sr Ex V P</officerTitle>
<otherText></otherText>
</reportingOwnerRelationship>
</reportingOwner>
<nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>COMMON STOCK</value>
</securityTitle>
<transactionDate><value>2003-06-19</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>M</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>11485</value>
</transactionShares>
<transactionPricePerShare><value>6.99</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>33510</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>D</value>
</directOrIndirectOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction><securityTitle><value>COMMON STOCK</value>
</securityTitle>
<transactionDate><value>2003-06-19</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>F</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>10530</value>
</transactionShares>
<transactionPricePerShare><value>8.00</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>D</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>22980</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>D</value>
</directOrIndirectOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction><securityTitle><value>COMMON STOCK</value>
</securityTitle>
<transactionDate><value>2003-06-19</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>M</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>855</value>
</transactionShares>
<transactionPricePerShare><value>5.38</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>23835</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>D</value>
</directOrIndirectOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction><securityTitle><value>COMMON STOCK</value>
</securityTitle>
<transactionDate><value>2003-06-19</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>F</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>670</value>
</transactionShares>
<transactionPricePerShare><value>8.00</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>D</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>23165</value>
<footnoteId id="F1"></footnoteId>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>D</value>
</directOrIndirectOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction><securityTitle><value>COMMON STOCK</value>
</securityTitle>
<transactionDate><value>2003-08-18</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>S</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>2640</value>
</transactionShares>
<transactionPricePerShare><value>6.98</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>0</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership><value>SHARES HELD ON BEHALF OF MINOR CHILDREN</value>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeTransaction>
</nonDerivativeTable>
<derivativeTable><derivativeTransaction><securityTitle><value>OPTIONS</value>
</securityTitle>
<conversionOrExercisePrice><value>6.99</value>
</conversionOrExercisePrice>
<transactionDate><value>2003-06-19</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>M</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>11485</value>
</transactionShares>
<transactionPricePerShare><value>0.00</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>D</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<exerciseDate><value>2000-08-01</value>
</exerciseDate>
<expirationDate><value>2003-08-01</value>
</expirationDate>
<underlyingSecurity><underlyingSecurityTitle><value>COMMON STOCK</value>
</underlyingSecurityTitle>
<underlyingSecurityShares><value>11485</value>
</underlyingSecurityShares>
</underlyingSecurity>
<postTransactionAmounts><valueOwnedFollowingTransaction><value>60057</value>
</valueOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>D</value>
</directOrIndirectOwnership>
</ownershipNature>
</derivativeTransaction>
<derivativeTransaction><securityTitle><value>OPTIONS</value>
</securityTitle>
<conversionOrExercisePrice><value>5.38</value>
</conversionOrExercisePrice>
<transactionDate><value>2003-06-19</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>M</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>855</value>
</transactionShares>
<transactionPricePerShare><value>0.00</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>D</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<exerciseDate><value>2002-11-30</value>
</exerciseDate>
<expirationDate><value>2009-11-30</value>
</expirationDate>
<underlyingSecurity><underlyingSecurityTitle><value>COMMON STOCK</value>
</underlyingSecurityTitle>
<underlyingSecurityShares><value>855</value>
</underlyingSecurityShares>
</underlyingSecurity>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>59202</value>
<footnoteId id="F2"></footnoteId>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>D</value>
</directOrIndirectOwnership>
</ownershipNature>
</derivativeTransaction>
</derivativeTable>
<footnotes><footnote id="F1">THIS AMOUNT REPRESENTS THE AMOUNT OF COMMON STOCK BENEFICIALLY OWNED FOLLOWING THE 6/19/03 TRANSACTIONS. SUBSEQUENTLY, ON AUGUST 11, 2003, THE COMPANY PAID A STOCK DIVIDEND OF ONE SHARE OF THE COMPANY'S COMMON STOCK FOR EACH TEN SHARES OF COMMON STOCK OWNED. THEREFORE, MR. DENNEY'S AMOUNT OF COMMON STOCK BENEFICIALLY OWNED AFTER THE STOCK DIVIDEND WAS APPROXIMATELY 25,476 SHARES.</footnote>
<footnote id="F2">REPRESENTS NUMBER OF OPTIONS BENEFICIALLY OWNED AFTER 6/19/03 TRANSACTIONS. SUBSEQUENT TO 8/11/03 STOCK DIVIDEND, TOTAL OPTIONS BENEFICIALLY OWNED IS APPROXIMATELY 65,120 OPTIONS.</footnote>
</footnotes>
<ownerSignature><signatureName>Lucy Woods POA for Arthur J Denney</signatureName>
<signatureDate>2003-08-19</signatureDate>
</ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----