ATP Oil & Gas Corporation Announces First Quarter 2006 Results and Operations Update

Business Wire, May 10, 2006

HOUSTON -- ATP Oil & Gas Corporation (Nasdaq:ATPG) today announced first quarter 2006 results and an operations update.

-- Commenced first production from three material projects:

--Mississippi Canyon 711 ("MC 711") in the Deepwater Gulf of Mexico,

--Tors in the U.K. North Sea, and

--L-06d in the Dutch North Sea;

--Achieved the final goal of the Employee Volvo Challenge by attaining a first quarter production exit rate of 160 MMcfe/d;

--Recorded production of 5.9 Bcfe or an average of 66 MMcfe/d for the first quarter;

--Improved financial strength with the issuance of a USD 150.0 million Series B Cumulative Perpetual Preferred Stock;

--Acquired Green Canyon Block 37, a property with logged oil and gas zones;

--Recorded revenue of USD 45.2 million and a net loss available to common shareholders of USD 9.9 million;

--Since the beginning of 2006, added 25 Bcfe of cash flow hedges for 2006 and 2007 at an average price of USD 10.94/Mcfe (USD 10.58/Mcfe for 2006 and USD 11.34/Mcfe for 2007)

Results of Operations

Natural gas and oil production was 5.9 Bcfe for the first quarter, compared to 5.8 Bcfe in the first quarter 2005. Compared to the first quarter 2005, first quarter U.S. natural gas price realizations increased 21% to USD 7.40 per Mcf, North Sea natural gas price realizations increased 19% to USD 9.48 per Mcf, and crude oil price realizations increased 11% to USD 44.72 per barrel. As a result of an increase in average realized prices and average sales volumes, natural gas and oil revenues were USD 45.2 million for the first quarter, compared to USD 37.0 million for the first quarter 2005.

Hurricane related repairs continued to impact the first quarter 2006 with lease operating expenses (LOE) in the Gulf of Mexico totaling USD 9.9 million and with approximately 30% associated with properties that did not contribute to production. For those properties with production, LOE amounted to USD 1.28 per Mcfe. LOE in the North Sea was USD 1.36 per Mcfe. For the first quarter 2005, LOE per Mcfe was USD 0.74 in the Gulf of Mexico and USD 1.24 in the North Sea.

General and administrative expense (G&A) totaled USD 5.8 million for the first quarter, compared to USD 4.2 million for the first quarter 2005. The increase was primarily due to higher costs for personnel, professional and legal fees, partially offset by lower administrative expenses associated with geological/geophysical activities.

Depreciation, depletion, and amortization (DD&A) per Mcfe was USD 2.91 for the first quarter, compared to USD 3.55 for the first quarter 2005. The lower rate for 2006 compared to 2005 is primarily due to one of our higher cost producing properties being shut-in during 2006 while awaiting the completion of hurricane related repairs.

ATP recorded a net loss available to common shareholders of USD 9.9 million or USD 0.34 per basic and diluted share in the first quarter, compared to net income available to common shareholders in the first quarter 2005 of USD 1.0 million or USD 0.03 per basic and diluted share. Results from the first quarter 2006 were impacted by the destructive aftermath of hurricanes Katrina and Rita, and the resultant industry rush to complete repairs and reconstruction efforts in an atmosphere of scarce resources and ever increasing costs due to the demand for such services.

The Company's selected operating statistics and financial information, included within this press release, contain additional information on our activities for the first quarter 2006 and comparable period in 2005.

NOTE: All figures are in USD unless otherwise stated.

Three Months Ended
                                                       March 31,
                                                  --------------------
                                                    2006       2005
                                                   --------  ---------
Selected Operating Statistics

Production
  Natural gas (MMcf)                                 5,033      4,594
  Oil and condensate (MBbls)                           150        198
  Natural gas equivalents (MMcfe)                    5,935      5,779
   Gulf of Mexico (MMcfe)                            5,326      5,238
   North Sea (MMcfe)                                   608        541

Average Prices (includes effect of cash
flow hedges)
  Natural gas (per Mcf)                               7.65       6.32
   Natural gas (per Mcf) - GOM                        7.40       6.10
   Natural gas (per Mcf) - N. Sea                     9.48       7.97
  Oil and condensate (per Bbl) - GOM                 44.72      40.15
  Natural gas, oil and condensate (per Mcfe)          7.62       6.40
  Lease operating expense (per Mcfe)                  1.80       0.79
   Lease operating expense (per Mcfe) - GOM           1.85       0.74
   Lease operating expense (per Mcfe) - N. Sea        1.36       1.24

Other Expenses, per Mcfe
  Depreciation, depletion and amortization (DD&A)     2.91       3.55
   DD&A - GOM                                         2.82       3.50
   DD&A - N. Sea                                      3.67       4.03

Selected Financial Data
(In Thousands, Except Per Share Data)

Oil and gas revenues, including settled
 derivatives (1)                                    45,225     36,980
Net income (loss)                                   (3,045)     1,000
Preferred dividends                                 (6,818)         -
Net income (loss) available to common
 shareholders                                       (9,863)     1,000
Per share, basic and diluted                         (0.34)      0.03

Average number of common shares outstanding
 Basic                                              29,435     28,924
                                                   ========  =========
 Diluted                                            29,435     29,782
                                                   ========  =========

(1) See oil and gas revenue reconciliation on the last page of this
    press release.