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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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<SEC-DOCUMENT>0001140361-07-015999.txt : 20070810
<SEC-HEADER>0001140361-07-015999.hdr.sgml : 20070810
<ACCEPTANCE-DATETIME>20070810160850
ACCESSION NUMBER:		0001140361-07-015999
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070731
FILED AS OF DATE:		20070810
DATE AS OF CHANGE:		20070810

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Regency Energy Partners LP
		CENTRAL INDEX KEY:			0001338613
		STANDARD INDUSTRIAL CLASSIFICATION:	CRUDE PETROLEUM & NATURAL GAS [1311]
		IRS NUMBER:				161731691
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1700 PACIFIC
		STREET 2:		SUITE 2900
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75201
		BUSINESS PHONE:		214-750-1771

	MAIL ADDRESS:	
		STREET 1:		1700 PACIFIC
		STREET 2:		SUITE 2900
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75201

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LEHMAN BROTHERS HOLDINGS INC
		CENTRAL INDEX KEY:			0000806085
		STANDARD INDUSTRIAL CLASSIFICATION:	SECURITY BROKERS, DEALERS & FLOTATION COMPANIES [6211]
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1130

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-51757
		FILM NUMBER:		071045464

	BUSINESS ADDRESS:	
		STREET 1:		LEHMAN BROTHERS
		STREET 2:		745 SEVENTH AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10019
		BUSINESS PHONE:		2125267000

	MAIL ADDRESS:	
		STREET 1:		LEHMAN BROTHERS
		STREET 2:		745 SEVENTH AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10019

	FORMER NAME:	
		FORMER CONFORMED NAME:	SHEARSON LEHMAN HUTTON HOLDINGS INC
		DATE OF NAME CHANGE:	19901017
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 3
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2007-07-31</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001338613</issuerCik>
        <issuerName>Regency Energy Partners LP</issuerName>
        <issuerTradingSymbol>RGNC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000806085</rptOwnerCik>
            <rptOwnerName>LEHMAN BROTHERS HOLDINGS INC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>745 SEVENTH AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Units</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1979152</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">By indirect, wholly-owned subsidiaries of the Reporting Person: 271,390 common units held by Lehman Brothers Inc.; 803,000 common units held by Lehman Brothers MLP Opportunity Fund LP; and 904,762 common units held by Lehman Brothers MLP Partners, LP</footnote>
    </footnotes>

    <remarks>JOINT FILER INFORMATION: Title of Derivative Securities: Common Units Issuer &amp;  Ticker Symbol: Regency Energy Partners L.P. (RGNC) Designated Filer: Lehman Brothers Holdings Inc. 745 Seventh Avenue New York, NY 10019 Other Joint Filer Information (all filers share the Reporting Person's address): Lehman Brothers Inc., a Delaware corporation, a direct wholly-owned subsidiary of the Reporting Person. LB I Group Inc., a Delaware corporation, a direct wholly-owned subsidiary of Lehman Brothers Inc. Lehman Brothers MLP Opportunity Associates LLC, a Delaware limited liability company, a direct wholly-owned subsidiary of the Reporting Person. Lehman Brothers MLP Opportunity Associates LP, a Delaware limited partnership, a direct wholly-owned subsidiary of Lehman Brothers MLP Opportunity Associates LLC and general partner of Lehman Brothers MLP Opportunity Fund LP, a Delaware limited partnership. Lehman Brothers MLP Partners, LP, a Delaware limited partnership, a wholly-owned subsidiary of LB I Grou
p Inc.</remarks>

    <ownerSignature>
        <signatureName>/s/  Barrett S. DiPaolo</signatureName>
        <signatureDate>2007-08-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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