Bear Wagner Specialists LLC Selected by MarkWest Energy Partners, L.P. to Trade Common Units on NYSE

New York , NY.— Bear Wagner Specialists LLC today announced that it was chosen by MarkWest Energy Partners, L.P. (NYSE: MWE) to trade its common units on the New York Stock Exchange. MarkWest Energy Partners, which had previously traded on the American Stock Exchange, began trading on the NYSE on May 2.

“We are pleased to welcome MarkWest Energy Partners into the Bear Wagner family of high-quality companies traded by our team of experienced specialists,” said Peter Murphy, chief executive officer of Bear Wagner Specialists. “At Bear Wagner, we have maintained a leadership position in exchange transfers by providing our clients with high levels of customer service and superior trading expertise.”

“We chose Bear Wagner Specialists as our partners on the floor of the NYSE because we believe they will deliver a superior market for our common units,” said Frank M. Semple, president and chief executive officer of MarkWest Energy Partners. “Bear Wagner’s substantial trading experience made our transfer from the American Stock Exchange to the NYSE smooth and successful.”