CEG Constellation Energy Grp. Common Stock

PostRock Energy Corporation (Nasdaq:PSTR) ("PostRock") today announced that it had purchased all of Constellation Energy Group, Inc.'s (NYSE:CEG) remaining Class B Member interests in Constellation Energy Partners LLC (NYSE:CEP). In the transaction, PostRock acquired 2,790,224 Class B Interests for $6 million in cash. PostRock now owns all of CEP's Class A Interests and 24.9% of its Class B Interests. In combination, the Interests are believed to represent a 26.4% voting interest in CEP.

PostRock and CEP both have the majority of their assets in the Cherokee Basin of Kansas and Oklahoma. Since last spring, PostRock has sought to work with CEP to explore opportunities to reduce costs and enhance value for the companies' respective investors. 

Commenting on the announcement, Terry W. Carter, PostRock's Chief Executive Officer, said, "Particularly in light of the current depressed gas market, we believe that PostRock and CEP should be aggressively pursuing joint operations and/or other ways to enhance shareholder value. Unfortunately, our mutual alternatives have been limited by the decisions of CEP's Board, which set unacceptable conditions relating to the confidentiality of any such discussions. Having now acquired more than a 15% interest in CEP, our alternatives are somewhat limited by Delaware statutes. Regardless, we will continue to try to work with CEP and to urge adoption of a more pragmatic approach to exploring our mutual opportunities."

PostRock Energy Corporation is engaged in the acquisition, exploration, development, production and transportation of oil and natural gas, primarily in the Cherokee Basin of Kansas and Oklahoma. The Company owns and operates over 3,000 wells and nearly 2,200 miles of gas gathering lines in the Basin. It also owns a 1,120 mile interstate natural gas pipeline, which transports natural gas from northern Oklahoma and western Kansas to Wichita and Kansas City.

The PostRock Energy Corp. logo is available at http://www.globenewswire.com/newsroom/prs/?pkgid=7221

CONTACT:  North Whipple
          Director, Finance & Investor Relations
          (405) 702-7423