Filed by Exelon Corporation

Reg. No. 333-155278

Pursuant to Rule 425 under the

Securities Act of 1933, as amended

Subject Company: NRG Energy, Inc.

 

On July 16, 2009, Exelon Corporation placed the following advertisement in the Wall Street Journal:

 

		IMPORTANT
If you have any questions or need assistance in voting the BLUE proxy card FOR Exelon’s proposals, please contact our proxy solicitor, Innisfree M&A Incorporated:
Stockholders Call Toll-Free: 877-750-9501
Banks and Brokers Call Collect: 212-750-5833
Remember, even if you have already voted NRG’s White proxy, you have every right to change your vote by executing the BLUE proxy card, since only your latest dated proxy card will count at the NRG meeting.

Important Information

This communication relates, in part, to the offer (the “Offer”) by Exelon Corporation (“Exelon”) through its direct wholly-owned subsidiary, Exelon Xchange Corporation (“Xchange”), to exchange each issued and outstanding share of common stock (the “NRG shares”) of NRG Energy, Inc. (“NRG”) for 0.545 of a share of Exelon common stock. This communication is for informational purposes only and does not constitute an offer to exchange, or a solicitation of an offer to exchange, NRG shares, nor is it a substitute for the Tender Offer Statement on Schedule TO or the Prospectus/Offer to Exchange included in the Registration Statement on Form S-4 (Reg. No. 333-155278) (including the Letter of Transmittal and related documents and as amended from time to time, the “Exchange Offer Documents”) previously filed by Exelon and Xchange with the Securities and Exchange Commission (the “SEC”). The Offer is made only through the Exchange Offer Documents. Investors and security holders are urged to read these documents and other relevant materials as they become available, because they will contain important information.

Investors and security holders can obtain copies of the materials described above (and all other related documents filed with the SEC) at no charge on the SEC’s website: www.sec.gov. Copies can also be obtained at no charge by directing a request for such materials to Innisfree M&A Incorporated, 501 Madison Avenue, 20th Floor, New York, New York 10022, toll free at 1-877-750-9501. Investors and security holders may also read and copy any reports, statements and other information filed by Exelon, Xchange or NRG with the SEC, at the SEC public reference room at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 or visit the SEC’s website for further information on its public reference room.