Highmark poised to buy West Penn.

Byline: Luis Fabregas

June 25--Highmark Inc. is expected to announce as early as next week that it will acquire financially troubled West Penn Allegheny Health System for about $500 million and assume full control over the region's second-largest hospital network, the Tribune-Review has learned.

West Penn Allegheny will become a subsidiary of Highmark, which will assume about $1 billion in liabilities from the health system, including pension plan obligations of more than $250 million, sources told the newspaper. The unprecedented buyout will set the stage for an all-out battle between Highmark, the state's largest health insurer with more than 3 million members in Western Pennsylvania alone, and juggernaut UPMC, the region's largest health care provider with the most hospital beds and doctors under contract and its own insurance plan. The rivals will …