ATP Reports Operational Results

ATP achieved total production of 43.8 Bcfe during the nine months ended September 30, 2007, a 24% increase over the first nine months of 2006. Oil, primarily from ATP's Gulf of Mexico deepwater program, continues to increase in importance to ATP, comprising 40% of total production volumes and 45% of total nine months oil and gas revenues of $393.6 million. For the first six days of November production has averaged approximately 250 MMcfe/d. In October, ATP produced an average of approximately 170 MMcfe/d and for the first nine months of 2007, ATP averaged 160 MMcfe/d. With the expansion at Gomez complete and the North Sea program on target for completion by year-end, ATP reaffirms its commitment to achieve 300 MMcfe/d before the end of 2007.

Production was 13.3 Bcfe (145 MMcfe per day) during the third quarter of 2007, a 17% decrease from the comparative period in 2006, primarily as a result of the subsea expansion work at Gomez. Revenues from production decreased 12% to $116.7 million during this same period. Price realizations reflect an overall 6% increase in our average sales price per Mcfe from $8.30 for the third quarter 2006 to $8.77 for the third quarter of 2007.

Lease operating expenses for the third quarter of 2007 decreased to $21.2 million ($1.59 per Mcfe) from $22.8 million ($1.43 per Mcfe) in the third quarter of 2006. Lease operating expenses declined in the Netherlands and UK during the three months ended September 30, 2007 compared to the same period of the prior year primarily due to lower production rates. In the Gulf of Mexico costs increased as a result of higher insurance premiums and an increase in costs due to our newly acquired Canyon Express Pipeline interests. During the three months ended September 30, 2007 and 2006, Gulf of Mexico costs included $2.2 million ($0.21 per Mcfe) and $0.4 million ($0.03 per Mcfe) of nonrecurring workover expenses.

General and administrative expense decreased 2% to $7.6 million for the third quarter of 2007 compared to $7.8 million for the same period of 2006. Noncash stock-based compensation expense decreased to $1.8 million for the three months ended September 30, 2007 compared to $3.2 million for the three months ended September 30, 2006. This decrease was offset by an increase in other salary expense.

ATP recorded a net tax benefit of $3.4 million during the quarter ended September 30, 2007, related to our foreign jurisdictions, based on the expected 2007 effective tax rate of each jurisdiction. The rates were determined based on the projected results of operations for the year, the valuation allowance released associated with the U.S. income before taxes for the quarter and permanent differences affecting the overall tax rate in each foreign jurisdiction. In the comparable quarter of 2006 we recorded a tax provision of $5.0 million related to our foreign jurisdictions. In the U.S., the tax provision recorded on our book income for both periods was offset by a release of valuation allowance.

For the third quarter 2007, ATP reported net income available to common shareholders of $2.3 million, or $0.08 per basic and diluted share, as compared with a net income available to common shareholders of $1.2 million, or $0.04 per basic and diluted share for the third quarter 2006.

Third quarter net income available to common shareholders was impacted by an impairment expense of $4.0 million and a loss on abandonment of $0.3 million. Research analysts typically exclude these nonrecurring charges from their published estimates. Accordingly, after adjusting for nonrecurring charges, ATP had net income available to common shareholders of $6.6 million or $0.22 per basic and diluted share. A reconciliation of non-GAAP net income for the quarter can be found near the end of this press release.

The company's selected operating statistics and financial information included within this press release contains additional information on activities for the third quarter and the comparable 2006 period.

                                 Three Months Ended Nine Months Ended
                                   September 30,      September 30,
                                 ------------------ ------------------
                                   2007     2006      2007     2006
                                 ------------------ ------------------
Selected Operating Statistics

  Natural gas (MMcf)                8,021    8,726    26,271   22,380
    Gulf of Mexico                  5,374    4,596    18,449   14,164
    North Sea                       2,647    4,130     7,822    8,216

  Oil and condensate (MBbls)          887    1,215     2,926    2,181
    Gulf of Mexico                    881    1,206     2,911    2,164
    North Sea                           6        9        15       17

  Natural gas equivalents
   (MMcfe)                         13,343   16,017    43,830   35,469
    Gulf of Mexico                 10,661   11,836    35,913   27,151
    North Sea                       2,682    4,181     7,917    8,318

Average Prices (includes effect
 of cash flow hedges)
  Natural gas (per Mcf)          $   7.25 $   7.22  $   8.28 $   7.29
    Gulf of Mexico                   7.63     7.35      8.22     7.47
    North Sea                        6.49     7.07      8.42     6.98
  Oil and condensate (per Bbl)      66.30    57.52     60.15    56.74
  Natural gas, oil and
   condensate (per Mcfe)             8.77     8.30      8.98     8.09

Other Expenses, per Mcfe
  Lease operating expense (per
   Mcfe)                         $   1.59 $   1.43  $   1.42 $   1.55
    Gulf of Mexico                   1.69     1.46      1.39     1.61
    North Sea                        1.17     1.34      1.57     1.34
  Depreciation, depletion and
   amortization (DD&A)               4.02     3.44      3.64     3.26
    Gulf of Mexico                   3.71     3.50      3.44     3.24
    North Sea                        5.25     3.24      4.57     3.31

Selected Financial Data
(In Thousands, Except Per Share

Oil and gas revenues, including
 settled derivatives (1)         $116,738 $132,822  $393,640 $286,952
Net income                          2,321   12,709    35,880   27,024
Preferred dividends                     -  (11,536)        -  (29,340)
Net income (loss) available to
 common shareholders                2,321    1,173    35,880   (2,316)

Net income (loss) per common
  Basic                          $   0.08 $   0.04  $   1.19 $  (0.08)
                                 ================== ==================
  Diluted                            0.08     0.04      1.17    (0.08)
                                 ================== ==================

Weighted average number of
 common shares outstanding
  Basic                            30,118   29,776    30,060   29,643
                                 ================== ==================
  Diluted                          30,771   30,406    30,669   30,342
                                 ================== ==================

(1) See oil and gas revenue reconciliation toward the end of this
 press release.
    Operations and Development

    Gulf of Mexico

Mississippi Canyon ("MC") 711 (Gomez Hub - 100% Working Interest) - The processing capacity upgrade project and the final subsea work for the MC 755 (Anduin) #2 ST-1 and MC 711 #8 wells has been completed. The Gomez Hub is now comprised of five flowing wells, compared to two wells for most of the 2006 period. As of October 31, 2007 the five wells were flowing at a combined gross rate of 20,000 bopd, with an additional 60 MMcf/d of associated gas. ATP holds an 85.5% net revenue interest in the Gomez Hub.

Ship Shoal ("SS") 351 (100% Working Interest) - ATP has completed and tied in all four wells at SS 351. Field production is currently at a facilities limit of 15 MMcfe/d net from three wells. The fourth well is scheduled to commence production later this quarter.

High Island ("HI") A-589 (100% Working Interest) - The jacket and deck of the fixed production platform at HI A-589 has been installed. The platform rig previously deployed at SS 351 is being moved to HI A-589 and should commence drilling in December of this year. ATP is planning to drill up to two wells at this location and expects first production in the first quarter of 2008.

Telemark Hub - MC 941/942 and Atwater Valley ("AT") 63 (100 % Working Interest) - ATP commenced the construction of a MinDOC (Deep Draft Floating Platform) for use at MC 941/942 and AT 63. Construction of the hull is underway in Texas and construction of the topside is progressing in Louisiana. The MinDOC sail-out is currently scheduled for the summer of 2008 with first production late in the fourth quarter 2008. The subsea well at AT 63 is currently designed to be tied into the MinDOC and the MinDOC will serve as the primary production facility for MC 941/942 and AT 63. The company is evaluating the construction of a second MinDOC to be located at AT 63 to maximize recoveries at that location.

North Sea

Tors - Kilmar & Garrow (85% Working Interest) - ATP is currently drilling a fourth well (K3) at Tors. The first lateral of the well has been successfully drilled and a completion liner is being run. The second lateral is underway and should be completed in early December. The K3 well is expected to be on production before the end of December and should expand production at the Tors field to 60-80 MMcfe per day, net.

Wenlock (100% Working Interest) - ATP successfully completed and tested the W1 well in July 2007 after drilling a company record 3,900' horizontal section. The W1 well encountered additional sands in an exploratory target in a new fault block. Host platform modifications have been performed and final commissioning is nearing completion. The W1 well should commence production before the end of the month. Beyond the W1 well, further upside is expected from two additional drilling opportunities which are currently under evaluation in the vicinity of Wenlock.

Acquisitions Update

In the October Central Gulf of Mexico Lease Sale 205, ATP was the apparent high bidder on two blocks, De Soto Canyon Block 355 and Viosca Knoll Block 863. De Soto Canyon Block 355 is located in approximately 7,618 feet of water and is in close proximity to the ATP operated Canyon Express pipeline system. Viosca Knoll Block 863 is located in approximately 958 feet of water and has logged hydrocarbons in two wells. Future development plans for each of these properties are currently being evaluated.

ATP is in discussions with parties regarding potential acquisitions and divestitures of other properties, including the sell-down of a portion of ATP's working interest in certain properties, in both the Gulf of Mexico and the North Sea. ATP expects to continue to pursue opportunities that meet its acquisition and divestiture strategy. Proved and probable reserves associated with these acquisitions and extension well discoveries are being evaluated by ATP's independent reservoir engineers and will be reported in conjunction with the 2007 year-end reserve report.

Hedging Update

In total for the fourth quarter of 2007 and beyond, ATP has 134 Bcfe hedged at an average price of $9.91 per Mcfe, representing potential future revenue of $1.3 billion. Since its second quarter earnings press release dated August 8, 2007, ATP has hedged an additional 39 Bcfe for the fourth quarter 2007 and beyond at an average price of $11.74 per Mcfe. Included in these hedges are 5.2 million barrels of crude oil fixed forward sales at prices ranging from $68.20 per Bbl to $91.65 per Bbl, 1.5 Bcf of U.S. natural gas fixed forward sales at prices ranging from $7.07 per Mcf to $7.16 per Mcf and 6.2 Bcf of U.K. natural gas swaps at prices ranging from $7.33 to $9.88 per Mcf (based on an exchange rate of 2.08 USD per GBP).

Capital Resources and Liquidity

Cash flow from operating activities was $237.8 million during the first nine months of 2007, compared to $105.3 million in cash flow from operating activities for the same 2006 period. Cash flow from operating activities prior to changes in assets and liabilities, a non-GAAP measure frequently used by research analysts, was $240.7 million for the first nine months of 2007, compared to $181.6 million for the same 2006 period.

During September 2007 ATP announced it had completed a $210 million unsecured subordinated term loan financing. The term loan matures in 2011 and can be repaid at any time subject to the Company's existing senior credit facility. The proceeds of the term loan are earmarked for near-term development opportunities and general corporate purposes.

ATP had $153.0 million in cash and cash equivalents on hand at September 30, 2007, compared to $182.6 million at December 31, 2006. Cash paid for acquisition and development activities for the nine months ended September 30, 2007 was $636.6 million, compared to $390.9 million for the same period in 2006. At September 30, 2007, ATP had GAAP working capital of $36.0 million, compared to working capital of $77.5 million at December 31, 2006. At September 30, 2007, ATP's $50 million revolving credit line was fully available.

ATP previously announced that it is evaluating an MLP or similar partnership structure for certain of its platform and pipeline assets. ATP completed its preliminary evaluation in June and determined that this initiative may be achievable and, if successful, may provide advantages for the company. ATP continues to work to identify both the assets and a structure that may be appropriate.