ATP Commences Public Offering of Common Stock

ATP Oil & Gas Corp.

ATP has commenced an underwritten public offering of 7.25 million shares of its common stock. The underwriters for the offering will also have the option to purchase up to 1.0875 million additional shares of common stock to cover any over-allotments.

ATP intends to use the net proceeds from the offering to support capital expenditures related to its drilling and development activities, including development of wells at its Telemark Hub in the deepwater Gulf of Mexico, to reduce indebtedness and for general corporate purposes.