Rosetta Completes Purchase of Oil and Gas Properties for $1.05 Billion

Rosetta Resources Inc., a newly formed corporation, has completed the purchase of all of the domestic oil and gas exploration and production assets formerly owned by Calpine Corporation for $1.05 billion, less approximately $60 million of transaction fees and expenses.

To finance the acquisition, Rosetta recently raised $725 million through the issuance of 45,312,500 of its common shares. Rosetta used the net proceeds from that transaction, together with $325 million of proceeds from a new credit facility, to purchase all of Calpine's domestic oil and gas exploration and production assets. The purchase price contemplates payment in full subject to the completion of certain post closing requirements. Following this transaction, Calpine no longer owns any interest in Rosetta.

The Rosetta common shares were offered in a private placement under Rule 144A, have not been registered under the Securities Act of 1933, and may not be offered or sold in the United States absent registration or an applicable exemption from registration requirements. This news release is issued pursuant to Rule 135c under the Securities Act and shall not constitute an offer to sell or the solicitation of an offer to buy. Securities laws applicable to private placements under Rule 144A limit the extent of information that can be provided at this time.

Rosetta Resources Inc. is an independent oil and gas company engaged in the acquisition, exploration, development and production of oil and gas properties in North America. Our operations are concentrated in the Sacramento Basin of California, South Texas, the Gulf of Mexico and the Rocky Mountains. Rosetta currently has 100 employees with primary offices in Houston, Texas and Denver, Colorado, and field offices in Rio Vista, California, Laredo, Texas and Magnolia, Arkansas.