Source: Brower Piven, A Professional Corporation

SHAREHOLDER ALERT: Brower Piven Encourages Investors Who Have Losses in Investment in ATP Oil & Gas Corp. 11.875% Senior Second Lien Exchange Notes to Contact Brower Piven Before the July 23, 2013 Lead Plaintiff Deadline -- ATPAQ

STEVENSON, Md., May 28, 2013 (GLOBE NEWSWIRE) -- Brower Piven, A Professional Corporation announces that a class action lawsuit has been commenced in the United States District Court for the Eastern District of Louisiana on behalf of purchasers of ATP Oil & Gas Corp. ("ATP" or the "Company") (OTC:ATPAQ) 11.875% Senior Second Lien Exchange Notes pursuant or traceable to the Company's December 16, 2010 Exchange of the Notes (the "Exchange").

If you have suffered a loss from investment in ATP Oil & Gas Corp. 11.875% Senior Second Lien Exchange Notes during the Exchange, you may obtain additional information about this lawsuit and your ability to become a lead plaintiff by contacting Brower Piven at www.browerpiven.com, by email at hoffman@browerpiven.com, by calling 410/415-6616, or at Brower Piven, A Professional Corporation, 1925 Old Valley Road, Stevenson, Maryland 21153. Attorneys at Brower Piven have combined experience litigating securities and class action cases of over 60 years.

No class has yet been certified in the above action. Members of the Class will be represented by the lead plaintiff and counsel chosen by the lead plaintiff. If you wish to choose counsel to represent you and the Class, you must apply to be appointed lead plaintiff no later than July 23, 2013 and be selected by the Court. The lead plaintiff will direct the litigation and participate in important decisions including whether to accept a settlement and how much of a settlement to accept for the Class in the action. The lead plaintiff will be selected from among applicants claiming the largest loss from investment in the Company.

The complaint accuses the defendants of violations of the Securities Act of 1933 by virtue of the defendants' failure to disclose the impact that two successive United States Department of the Interior moratoria for deepwater drilling operations in the Gulf of Mexico had on the Company's operations and revenues and the Company's breach of certain credit agreements by engaging in disguised financing arrangements that were designed to evade the requirements of such credit agreements. According to the complaint, on August 17, 2012, the Company filed for bankruptcy. As of the date the securities class action was filed, it has been reported that ATP 11.875% Senior Second Lien Exchange Notes were trading at approximately four cents ($0.04) on the dollar.

If you choose to retain counsel, you may retain Brower Piven without financial obligation or cost to you, or you may retain other counsel of your choice. You need take no action at this time to be a member of the class.