Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  LEHMAN BROTHERS HOLDINGS INC
2. Date of Event Requiring Statement (Month/Day/Year)
07/31/2007
3. Issuer Name and Ticker or Trading Symbol
Regency Energy Partners LP [RGNC]
(Last)
(First)
(Middle)
745 SEVENTH AVENUE
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

NEW YORK, NY 10019
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Units 1,979,152
I
See Footnote (1)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
LEHMAN BROTHERS HOLDINGS INC
745 SEVENTH AVENUE
NEW YORK, NY 10019
    X    

Signatures

/s/ Barrett S. DiPaolo 08/10/2007
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) 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
 
Remarks:
JOINT FILER INFORMATION: Title of Derivative Securities: Common Units Issuer &  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 Group Inc.

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