ATP Oil & Gas Corporation

NASDAQ: ATPG

Forward-looking Statement

This presentation contains projections and other forward looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. These projections and statements reflect the Companys current view with respect to future events and financial performance. No assurances can be given, however, that these events will occur or that these projections will be achieved, and actual results could differ materially from those projected as a result of certain factors. A discussion of these factors is included in the Company documents filed with the Securities and Exchange Commission.

This presentation does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy or an attempt to influence any voting of securities, by any person.ATPOil & GasCorporation

Area of OperationsOver 50 blocks in Gulf of Mexico7 blocks in North Sea

Company Overview

Development and production company

Offshore solution provider for explorationoriented majors and independents

Unique, repeatable strategy

Our D&P Strategy WorksATPOil & GasCorporation

Company HistoryATPOil & GasCorporationATP was founded in 1991 and completed an initial public offering in February 2001

Company Profile

Production:2001 Actual:25.7 Bcfe2002 Guidance:26.5 BcfeActual Through 9/30/02:21.4 Bcfe

Proven reserves 2001: 235 Bcfe

3-year reserve replacement:374%

3-year F&D costs:$0.96/Mcfe

Recent FocusATPOil & GasCorporation

Increasing financial flexibility Reduced bank debt $14 million in 2002Increased working capital $30 million in 2002Discretionary cash flow increased from $4 to $48 million (97-01)Profitable in second and third quarter 2002

Exceeding operating goalsBeat first, second, and third quarter production guidance Developing North Sea reservesPipeline installed and well drilling at HelvellynFirst production in 2003

2002 Development ActivityGulf of Mexico ATP is moving 32 Bcfe from non-producing to proven developed producing properties (PDP) for less than $20 million

3Q02 Production and Development HighlightsProduction 3Q026.536 Bcfeincrease over 3Q01 increase over announced guidance of 6.500 Bcfe

2002 YTD 21.5 Bcfe

increase of 16% over 2001record for first nine months

Development

25 Bcfe moved to PDPLarger PDP component of reserves at 9/30/02 than 12/31/01

Near Term 2002 DevelopmentATPOil & GasCorporation

Q3 ActivityRecompletion of EC 240, SM 7 and WC 462Production to contribute in 4Q02

Q4 Development of 7 projectsWC 101, WC 284, EI 714 recompletions and stimulationsProduction to contribute in 1Q 03

Production on schedule for the 7th consecutive year of increase

4th Quarter 2002Development OperationsWC 101WC 284EI 71

West Cameron 101ATPOil & GasCorporationWater Depth: 43Working Interest: 100%Net Revenue Interest: 73.33%Platform/Wells:One well caisson.Producing Sands: Miocene Marg A 53 thru 55 Sands at 13,000 TVDCurrent Status: Caisson waiting on completion of WC 101 #2 wellWC 204 (at left) facilities to be used at WC 101

West Cameron 101 #2 Log

Future Development (2003 2005)100% of properties ATP operated

North Sea DevelopmentsATPOil & GasCorporation

Southern Gas Basin of North SeaThe TorsHelvellynVenture2002 Out of Round Award

Water Depth: 90Working Interest: 50%Net Revenue Interest: 50%Platform/Wells:SubseaFirst Production:Projected 2003 Producing Sands: Rotliegend/Carboniferous First well drilled:1985First well tested:47/10-1 well tested at 29.4 MMcfepd

Current Status:Well drilling at 11,000 +/- feet(measured depth)

Development 2002Projected production 2003

Helvellyn Development August 2002 Pipeline Lay

Oil & GasCorporationDevelopment 2003Projected production 2004

Development 2004Projected production 2005

Development 2004Projected production 2005

Third Quarter 2002 Financial Overview

Debt Reduction Program

($ in millions)

Working Capital Increased $30 million +Bank and Subordinated DebtDecreased $12 million

=Overall Capital LiquidityImprovement $42 million

($ in millions)Gross Margin82% YTD 02Note: Revenues reflect the effects of settled hedging activity

Bank & subordinated debt/proven reserves(1)$0.40 / Mcfe

LTM EBITDA / Interest Expense 6.6x

Bank & subordinated debt / LTM EBITDA 1.5x

YTD 3Q02 Discretionary cash flow $42 million

At September 30, 2002

Why Should ATP Be In Your Portfolio?

Compares favorably to other offshore operators

Our Peers

Compares favorably to other offshore operators

Attractive valuation

Attractive ValuationP/CFPS significantly below peers

Attractive ValuationEV trades at a discount to NAVNote: Debt as of 9/30/02; share price as of 11/26/02

Why Should ATP Be In Your Portfolio?Compares favorably to other offshore operators

Attractive valuation

Efficient offshore operator

Efficient Offshore OperatorLowest production costs in the group

Compares favorably to other offshore operators

Attractive valuation

Efficient offshore operator

Rate of return focused

Why Should ATP Be In Your Portfolio?

Compares favorably to other offshore operators

Attractive valuation

Efficient offshore operator

Rate of return focused

History of producing results

Discretionary Cash FlowRevenue($ in millions)

Production (BCFE)Proven Reserves (BCFE)

NASDAQ: ATPG ATP Oil & Gas Corporation 4600 Post Oak Place, Suite 200 Houston, TX 77027-9726 713-622-3311 ATP Oil & Gas (UK) LimitedVictoria House, London Square, Cross LanesGuildford, Surrey GU1 1UJ United Kingdom44 (0) 1483 307200

www.atpog.com

ON 10/16/02 2003 FC CFPS was $2.67On 11/12/02 2003 FC CFPS was $2.74