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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 vBwuwsUl7yrz29KtjBZdSQ==

<SEC-DOCUMENT>0001125282-06-002478.txt : 20060501
<SEC-HEADER>0001125282-06-002478.hdr.sgml : 20060501
<ACCEPTANCE-DATETIME>20060501165730
ACCESSION NUMBER:		0001125282-06-002478
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060428
FILED AS OF DATE:		20060501
DATE AS OF CHANGE:		20060501

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CASTLE ENERGY CORP
		CENTRAL INDEX KEY:			0000709355
		STANDARD INDUSTRIAL CLASSIFICATION:	CRUDE PETROLEUM & NATURAL GAS [1311]
		IRS NUMBER:				760035225
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		ONE RADNOR CORPORATE CTR STE 250
		STREET 2:		100 MATSONFORD RD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087
		BUSINESS PHONE:		6109959400

	MAIL ADDRESS:	
		STREET 1:		ONE RADNOR CORPORATE CENTER SUITE 250
		STREET 2:		100 MATSONFORD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MINDEN OIL & GAS INC/NEW
		DATE OF NAME CHANGE:	19861117

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MINDEN HOLDING CO
		DATE OF NAME CHANGE:	19830310

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KELLER JOHN P
		CENTRAL INDEX KEY:			0001024512
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		STATE OF INCORPORATION:			MI
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-10990
		FILM NUMBER:		06795899

	BUSINESS ADDRESS:	
		STREET 1:		C/O OLD KENT FINANCIAL
		STREET 2:		ONE VANDENBERG CENTER
		CITY:			GRAND RAPIDS
		STATE:			MI
		ZIP:			49503
		BUSINESS PHONE:		6167715000

	MAIL ADDRESS:	
		STREET 1:		3400 NORTH WOLF ROAD
		CITY:			FRANKLIN PARK
		STATE:			IL
		ZIP:			60131
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-04-28</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0000709355</issuerCik>
        <issuerName>CASTLE ENERGY CORP</issuerName>
        <issuerTradingSymbol>CECX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001024512</rptOwnerCik>
            <rptOwnerName>KELLER JOHN P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3400 NORTH WOLF ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>FRANKLIN PARK</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60131</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $0.50 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2006-04-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>111000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Disposed of pursuant to merger agreement between issuer and Delta Petroleum Corporation in exchange for 129,189 shares of Delta Petroleum Corporation common stock having a market value of $20.03 per share on the effective date of the merger plus cash for any resulting fractional share remaining.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>William C. Liedtke III for John P. Keller</signatureName>
        <signatureDate>2006-05-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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