July 15, 2011

Bernstein Liebhard LLP is investigating whether the Board of Directors of Petrohawk Energy Corporation (“Petrohawk” or the “Company”) (NYSE: HK) breached its fiduciary duty to its shareholders in agreeing to sell Petrohawk to BHP Billiton.

Under the terms of the agreement, Petrohawk shareholders will receive $38.75 in cash for each share they own. The investigation is focused on the potential unfairness of the price to Petrohawk shareholders and the process by which the Petrohawk Board of Directors considered and approved the transaction.

If you are interested in discussing your rights as a Petrohawk shareholder and/or have information relating to the matter, please contact U. Seth Ottensoser at (877) 779-1414 or Ottensoser@bernlieb.com.

Bernstein Liebhard has pursued hundreds of securities, consumer and shareholder rights cases and recovered almost $3 billion for its clients. It has been named to The National Law Journal’s “Plaintiffs’ Hot List” in each of the last eight years.