Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN 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 *
H&F INVESTORS IV LLC
  2. Issuer Name and Ticker or Trading Symbol
NRG ENERGY, INC. [NRG]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) __X__ Other (specify below)
See Remarks
(Last)
(First)
(Middle)
ONE MARITIME PLAZA, 12TH FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
08/15/2006
(Street)

SAN FRANCISCO, CA 94111
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock, par value $0.01 per share 08/15/2006   S   3,207,977 D $ 48.41 (1) 3,207,976 I See footnotes (1) (2) (3)
Common Stock, par value $0.01 per share 08/15/2006   S   262,115 D $ 48.41 (1) 262,116 I See footnotes (1) (2) (3)
Common Stock, par value $0.01 per share 08/15/2006   S   1,179 D $ 48.41 (1) 1,179 I See footnotes (1) (2) (3)
Common Stock, par value $0.01 per share 08/15/2006   S   84,588 D $ 48.41 (1) 84,588 I See footnotes (1) (2) (3)
Common Stock, par value $0.01 per share 08/15/2006   S   661,012 D $ 48.41 (1) 661,012 I See footnotes (1) (2) (3)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
H&F INVESTORS IV LLC
ONE MARITIME PLAZA, 12TH FLOOR
SAN FRANCISCO, CA 94111
    X   See Remarks
HELLMAN & FRIEDMAN CAPITAL PARTNERS IV LP
ONE MARITIME PLAZA, 12TH FLOOR
SAN FRANCISCO, CA 94111
    X   See Remarks
H&F INTERNATIONAL PARTNERS IV-A, L.P.
ONE MARITIME PLAZA, 12TH FLOOR
SAN FRANCISCO, CA 94111
    X   See Remarks
H&F International Partners IV-C, L.P.
ONE MARITIME PLAZA, 12TH FLOOR
SAN FRANCISCO, CA 94111
    X   See Remarks
H&F EXECUTIVE FUND IV, L.P.
ONE MARITIME PLAZA, 12TH FLOOR
SAN FRANCISCO, CA 94111
    X   See Remarks
H&F TGN AIV, L.P.
ONE MARITIME PLAZA, 12TH FLOOR
SAN FRANCISCO, CA 94111
    X   See Remarks

Signatures

 /s/ Mitchell Cohen as Managing Director of H&F Investors IV, LLC   08/16/2006
**Signature of Reporting Person Date

 /s/ Mitchell Cohen as Managing Director of H&F Investors IV, LLC, as General Partner of Hellman & Friedman Capital Partners IV, L.P.   08/16/2006
**Signature of Reporting Person Date

 /s/ Mitchell Cohen as Managing Director of H&F Investors IV, LLC, as General Partner of H&F TGN AIV, L.P.   08/16/2006
**Signature of Reporting Person Date

 /s/ Mitchell Cohen as Managing Director of H&F Investors IV, LLC, as General Partner of H&F International Partners IV-A, L.P.   08/16/2006
**Signature of Reporting Person Date

 /s/ Mitchell Cohen as Managing Director of H&F Investors IV, LLC, as General Partner of H&F International Partners IV-C, L.P.   08/16/2006
**Signature of Reporting Person Date

 /s/ Mitchell Cohen as Managing Director of H&F Investors IV, LLC, as General Partner of H&F Executive Fund IV, L.P.   08/16/2006
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(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) On August 15, 2006, Hellman & Friedman Capital Partners IV, L.P. ("HFCP IV"), H&F International Partners IV-A, L.P. ("HFIP IV-A"), H&F International Partners IV-C, L.P. ("HFIP IV-C"), H&F Executive Fund IV, L.P. ("HFEF IV"), H&F TGN AIV, L.P. ("H&F AIV", and together with HFCP IV, HFIP IV-A, HFIP IV-C and HFEF IV, the "H&F Partnerships") sold respectively 3,207,977, 262,115, 1,179, 84,588 and 661,012 shares (4,216,871 shares in total) of NRG Energy, Inc.'s common stock (the "Common Stock"), to Morgan Stanley & Co. Incorporated at a price of $48.41 per share (the "Resale"). Following completion of the Resale, HFCP IV, HFIP IV-A, HFIP IV-C, HFEF IV and H&F AIV directly own respectively 3,207,976, 262,116, 1,179, 84,588 and 661,012 shares of Common Stock reported as beneficially owned in the above table.
(2) H&F Investors IV, LLC ("H&F Investors") is the general partner of each of the H&F Partnerships. The investment decisions of each of the H&F Partnerships are made by the investment committee of H&F Investors, which indirectly exercises voting and investment power with respect to the Common Stock held by the H&F Partnerships. Accordingly, H&F Investors may be deemed to share beneficial ownership of the shares of Common Stock held by the H&F Partnerships.
(3) Pursuant to Rule 16a-1(a)(4) of the Securities Exchange Act of 1934, as amended, H&F Investors herein states that this filing shall not be deemed an admission that it is the beneficial owner of any of the shares of Common Stock covered by this Statement. H&F Investors disclaims beneficial ownership of the Common Stock, except to the extent of its pecuniary interest in such shares of Common Stock.
 
Remarks:
As described in Amendment No. 1 to Schedule 13D ("Amendment No. 1") filed on August 11, 2006 with respect to the Common Stock by the Reporting Persons and the other filers listed on the signature pages thereto, as of the date of Amendment No. 1, the H&F Partnerships and certain other Funds (as defined in Amendment No. 1) may have been deemed to be a "group" under Section 13(d) of the Securities Exchange Act and accordingly each Reporting Person may have been deemed to have beneficial ownership of 10% or more of the Common Stock.  Following the completion of the Resale, the Reporting Persons are not presently acting in a manner that could deem them to be a "group" with the other Funds within the meaning of Section 13(d) of the Securities Exchange Act with respect to the Common Stock.  Each Reporting Person expressly disclaims membership in any such group for the purposes of Section 13(d) of the Securities Exchange Act or for any other purpose.

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