8-K

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT PURSUANT

TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): February 23, 2004

ATP OIL & GAS CORPORATION

(Exact name of registrant as specified in its charter)

Texas	000-32261	76-0362774
(State or other jurisdiction	(Commission File Number)	(I.R.S. Employer
of incorporation)		Identification No.)

4600 Post Oak Place, Suite 200

Houston, Texas 77027

(Address of principal executive offices) (Zip code)

Registrant’s telephone number, including area code: (713) 622-3311

Item 5. Other Events.

ATP Oil & Gas Corporation has agreed to certain amendments to its senior credit facility.

Amendments to Credit Agreement

As announced in our quarterly report on Form 10-Q for the period ended September 30, 2003, we executed an amendment in November 2003 to our credit agreement that, among other things, contemplated a new $15 million Tranche to be secured by our North Sea oil and gas properties in addition to our U.S. properties. On December 3, 2003, we executed a second amendment to our credit agreement, which implemented the $15 million UK Tranche, with a maturity date of February 16, 2004, implemented a borrowing base coverage test of 150% commencing February 16, 2004, modified several of the financial covenants contained in the credit agreement and added new reporting and compliance covenants and events of default under the credit agreement. We incurred fees of approximately $750,000 in connection with the execution of the second amendment, half of which were paid on December 3, 2003 with the remainder paid February 16, 2004.

On February 23, 2004 we finalized the conditions subsequent to the third amendment to the credit agreement which is effective as of February 16, 2004. The third amendment extended the maturity of the UK Tranche to January 31, 2005, reduced the borrowing base coverage test from 150% of the amounts outstanding under our credit facility to 125%, extended the measuring date for such test from February 16, 2004 to April 30, 2004, imposed a new borrowing base reserve of $14 million at April 30, 2004 and provided waivers for non-compliance with certain financial covenants as of December 31, 2003. As consideration for the execution of the third amendment, we issued warrants which we may repurchase under certain conditions to our lenders to purchase 750,000 shares of our common stock, exercisable at a price of $6.75 per share.

Credit Facility Obligations

In summary, the credit facility which was executed August 13, 2003 and was amended as noted above consists of four Tranches with an aggregate commitment of $125 million secured by substantially all of the company’s U.S. oil and gas properties, the capital stock of our foreign subsidiaries and the company’s UK oil and gas properties. The U.S. portion of the credit facility (up to $110 million) matures in August 2007 and the UK portion ($15 million) now matures on January 31, 2005. Advances under the U.S. portion of the credit facility bear interest at the base rate plus a margin of 1.0% to 8.0%, depending on the amount outstanding. The current average effective interest rate on the domestic facility is approximately 9% per annum. Advances under the UK portion of the credit facility bear interest at the rate of 15% per annum.

The following description summarizes terms of the second and third amendments and is qualified in its entirety by reference to the amendments, copies of which are included as exhibits to this filing.

As noted above, the maturity date of the $15 million UK Tranche was extended from February 16, 2004 to January 31, 2005. During May, June and July 2004 we are required to apply 75% of the net cash proceeds (essentially revenues from production less operating costs) attributable to production from our Helvellyn field to permanently reduce the amounts

2

outstanding under the UK portion of our credit facility. Beginning in August 2004 and extending until the maturity on January 31, 2005, this percentage decreases to 50%. A minimum payment of $500,000 per month will be required during the period May 2004 through maturity; however, the company anticipates that the net cash proceeds percentage will exceed the $500,000 minimum monthly payment.

The U.S. portion of our credit facility is subject to a borrowing base that is reviewed monthly. Since August 13, 2003, the borrowing base under our credit facility has been equal to 65% of the PV10 value of our domestic producing reserves plus 45% of the PV10 value of our domestic developed non-producing reserves plus 30% of the PV10 value of our domestic proved undeveloped reserves, up to a maximum of the lesser of 60% of the value of our domestic developed producing and non-producing reserves and $45 million. On April 1, 2004, the portion of our borrowing base attributed to our domestic proved undeveloped reserves will be reduced to 25% of the value of such properties, with a maximum of the lesser of 50% of the value of our developed reserves and $35 million. On May 1, 2004, the portion of our borrowing base attributed to our domestic proved undeveloped reserves will be further reduced to 20% of the value of such reserves, with a maximum of the lesser of 25% of the value of our developed properties and $25 million. If the outstanding borrowings under the U.S. portion of our credit facility exceed our borrowing base, less applicable availability reserve requirements, we are required to repay such excess immediately. From and after April 30, 2004, we will be subject to a collateral coverage test under which the sum of our borrowing base plus 65% of the PV10 value of the reserves from our Helvellyn field must be greater than 125% of the aggregate amount outstanding under our credit facility. We are also required to reduce the overall size of our existing credit facility in the future by an amount equal to the amount paid by us to satisfy any payment obligations we are ultimately determined to have with respect to our Legacy dispute. With the reclassification of our projects currently being developed from non-producing to proved developed producing reserves, we expect to be able to comply with these requirements. Delays in commencing production on these projects, however, would make it difficult for us to meet these requirements and would require us to reduce the amounts outstanding under our credit facility.

On April 30, 2004 a new $14 million reserve against the US portion of our borrowing base will effectively reduce the available credit for our US proved reserves from a maximum of $105.5 million, after giving effect to the current $4.5 million availability reserve, to $91.5 million, based on the current calculation of our borrowing base. We currently have outstanding $96.0 million under the U.S. portion of our existing credit facility. Changes in the amount and type of reserves reflected on our reserve report will affect the calculation of our borrowing base. In order to satisfy this additional reserve requirement, remain in compliance with our existing credit facility and meet our capital expenditure needs, we expect to require approximately $30 million in additional financing before the end of the first quarter 2004. We are aggressively pursuing additional capital and believe we can be successful in obtaining funding in at least this amount to comply with these requirements or a greater amount to refinance our current credit facility in its entirety, although there can be no assurance. Our inability to execute a capital transaction and to maintain compliance with the covenants under our existing credit facility, or to obtain additional waivers or amendments under that facility, would materially and adversely affect our financial position, results of operations and cash flows.

3

The third amendment to our credit facility waived non-compliance with the consolidated debt coverage and the minimum consolidated EBITDA requirements applicable for the period ending December 31, 2003. In conjunction with this third amendment, certain EBITDA covenants were reset for the period through April 30, 2004. The company expects that it will be able to comply with these new covenants during such time period.

As consideration for the execution of the third amendment, we issued warrants to our lenders to purchase 750,000 shares of our common stock, exercisable at a price of $6.75 per share. We have the right to repurchase the warrants in whole, but not in part, at any time prior to May 17, 2004 for $750,000, provided that the availability under our credit facility is at least $7.5 million after giving effect to such redemption.

Item 7. Financial Statements and Exhibits.

4.1	Warrant Shares Registration Rights Agreement dated as of February 16, 2004 by and between ATP Oil & Gas Corporation and each of the Holders set forth on the execution pages thereof
4.2	Warrant dated as of February 16, 2004 by and between ATP Oil and Gas Corporation and Ableco Holding LLC
4.3	Warrant dated as of February 16, 2004 by and between ATP Oil & Gas Corporation and Wells Fargo Foothill, Inc.
10.1	Second Amendment to the Second Amended and Restated Financing Agreement dated December 3, 2003, among ATP Oil & Gas Corporation, Ableco Finance LLC, as agent, and Wells Fargo Foothill, Inc. as funding agent
10.2	Third Amendment to the Second Amended and Restated Financing Agreement dated February 16, 2004, among ATP Oil & Gas Corporation, Ableco Finance LLC, as agent, and Wells Fargo Foothill, Inc. as funding agent
99.1	Press release issued February 27, 2004

Item 9. Regulation FD Disclosure.

On February 27, 2004, ATP Oil & Gas Corporation, a Texas corporation, issued a press release, a copy of which is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

4

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	ATP OIL & GAS CORPORATION
Date: February 27, 2004	By:	/s/ ALBERT L. REESE, JR.
		Albert L. Reese, Jr. Senior Vice President and Chief Financial Officer

5

EX-4.1

Exhibit 4.1

REGISTRATION RIGHTS AGREEMENT

by and between

ATP OIL & GAS CORPORATION

and

THE INITIAL HOLDER SPECIFIED ON THE SIGNATURE PAGES HEREOF

Dated as of February 16, 2004

TABLE OF CONTENTS

			Page
1.	DEFINITIONS		1
2.	REGISTRATION UNDER THE SECURITIES ACT		5
	2.1.	Demand Registration	5
	2.2.	Incidental Registration	8
	2.3.	F-3 or S-3 Registration; Shelf Registration	10
	2.4.	Underwritten Offerings	11
	2.5.	Expenses	11
	2.6.	Postponements	12
3.	HOLDBACK ARRANGEMENTS		13
	3.1.	Restrictions on Sale by Holders of Registrable Securities	13
	3.2.	Restrictions on Sale by the Company and Others	13
4.	REGISTRATION PROCEDURES		13
	4.1.	Obligations of the Company	13
	4.2.	Seller Information	18
	4.3.	Notice to Discontinue	18
5.	INDEMNIFICATION; CONTRIBUTION		18
	5.1.	Indemnification by the Company	18
	5.2.	Indemnification by Holders	19
	5.3.	Conduct of Indemnification Proceedings	20
	5.4.	Contribution	20
	5.5.	Other Indemnification	21
	5.6.	Indemnification Payments	21
6.	GENERAL		21
	6.1.	Adjustments Affecting Registrable Securities	21
	6.2.	Registration Rights to Others	21
	6.3.	Availability of Information; Rule 144; Rule 144A; Other Exemptions	21
	6.4.	Amendments and Waivers	22
	6.5.	Notices	22
	6.6.	Successors and Assigns	24
	6.7.	Counterparts	25
	6.8.	Descriptive Headings, Etc.	25
	6.9.	Severability	25
	6.10.	Choice of Law and Venue; Jury Trial Waiver	25
	6.11.	Remedies; Specific Performance	26
	6.12.	Entire Agreement	26
	6.13.	Further Assurances	26
	6.14.	Construction	26
	6.15.	No Inconsistent Agreement	27
	6.16.	Costs and Attorneys’ Fees	27

REGISTRATION RIGHTS AGREEMENT (the “Agreement”) dated as of February 16, 2004, by and among ATP OIL & GAS CORPORATION, a Texas corporation (the “Company”), and each Initial Holder specified on the signature pages to this Agreement.

W I T N E S S E T H :

WHEREAS, simultaneously herewith, in connection with that certain Second Amended and Restated Financing Agreement, dated as of August 13, 2003, as amended pursuant to the Consent and Amendment No. 1, dated as of November 14, 2003, and Amendment No. 2, dated as of December 3, 2003, and as supplemented by the Joinder Agreement, dated as of December 3, 2003 (as amended, supplemented or otherwise modified from time to time, the “Financing Agreement”), by and among the Company, as the borrower, each subsidiary of the Company listed as a guarantor on the signature pages thereto, each of the lenders from time to time party thereto, Ableco Finance LLC, as collateral agent and administrative agent for the lenders, and Wells Fargo Foothill, Inc., as funding agent for the lenders, the parties thereto have entered in an Amendment No. 3, dated as February 16, 2004, to the Financing Agreement.

WHEREAS, in order to induce the Lenders to enter into Amendment No. 3 to the Financing Agreement, the Company is issuing and delivering to Ableco Holding LLC and to Wells Fargo Foothill, Inc. or their respective nominees or assigns (the “Initial Holder”) warrants (the “Warrants”) to purchase Shares (the Shares issued or issuable upon exercise of the Warrants are hereinafter referred to as the “Warrant Shares”), and the Company has further agreed to provide certain registration rights in respect of the Registrable Securities (as defined below) on the terms and subject to the conditions set forth herein.

NOW, THEREFORE, in consideration of the premises and of the mutual agreements contained herein and in order to induce the Lenders to enter into the Financing Agreement and the Lenders to make and maintain the Loans pursuant to the Financing Agreement, the Company hereby agrees with each Initial Holder as follows:

1. DEFINITIONS. As used in this Agreement, the following terms shall have the following meanings:

“Affiliate” shall mean (i) with respect to any Person, any other Person directly or indirectly controlling or controlled by or under direct or indirect common control with such Person, and (ii) with respect to any individual, shall also mean the spouse, sibling, child, step-child, grandchild, niece, nephew or parent of such Person, or the spouse thereof.

“Company” shall have the meaning set forth in the preamble.

“Demand Registration” shall mean a registration required to be effected by the Company pursuant to Section 2.1.

“Demand Registration Statement” shall mean a registration statement of the Company which covers the Registrable Securities requested to be included therein pursuant to the provisions of Section 2.1 and all amendments and supplements to such registration statement, including post-effective amendments, in each case including the Prospectus contained therein, all

exhibits thereto and all material incorporated by reference (or deemed to be incorporated by reference) therein.

“Exchange Act” shall mean the Securities Exchange Act of 1934, as amended from time to time, and the rules and regulations thereunder, or any successor statute.

“Financing Agreement” shall have the meaning set forth in the preamble.

“Holders” shall mean the Initial Holder for so long as it is the registered owner of any Registrable Securities and such of its respective heirs, successors and permitted assigns (including any permitted transferees of Registrable Securities) who acquire or are otherwise the transferee of Registrable Securities, directly or indirectly, from such Initial Holder (or any subsequent Holder), for so long as such heirs, successors and permitted assigns are the registered owner of any Registrable Securities. For purposes of this Agreement, a Person will be deemed to be a Holder whenever such Person holds an option to purchase, or a security convertible into or exercisable or exchangeable for, Registrable Securities, whether or not such purchase, conversion, exercise or exchange has actually been effected and disregarding any legal restrictions upon the exercise of such rights. Registrable Securities issuable upon exercise of an option or upon conversion, exchange or exercise of another security shall be deemed outstanding for the purposes of this Agreement.

“Holders’ Counsel” shall mean one firm of counsel (per registration) to the Holders of Registrable Securities participating in such registration, which counsel shall be selected (i) in the case of a Demand Registration, by the Initiating Holders holding a majority of the Registrable Securities for which registration was requested in the Request, and (ii) in all other cases, by the Majority Holders of the Registration.

“Incidental Registration” shall mean a registration required to be effected by the Company pursuant to Section 2.2.

“Incidental Registration Statement” shall mean a registration statement of the Company, which covers the Registrable Securities requested to be included therein pursuant to the provisions of Section 2.2 and all amendments and supplements to such registration statement, including post-effective amendments, in each case including the Prospectus contained therein, all exhibits thereto and all material incorporated by reference (or deemed to be incorporated by reference) therein.

“Initial Holder” shall mean the Person specified as such on the signature pages to this Agreement on the date hereof.

“Initiating Holders” shall mean, with respect to a particular registration, the Holders who initiated the Request for such registration.

“Majority Holders” shall mean one or more Holders of Registrable Securities who would hold a majority of the Registrable Securities then outstanding.

-2-

“Majority Holders of the Registration” shall mean, with respect to a particular registration, one or more Holders of Registrable Securities who would hold a majority of the Registrable Securities to be included in such registration.

“NASD” shall mean the National Association of Securities Dealers, Inc.

“Person” shall mean any individual, firm, partnership, corporation, trust, joint venture, association, joint stock company, limited liability company, unincorporated organization or any other entity or organization, including a government or agency or political subdivision thereof, and shall include any successor (by merger or otherwise) of such entity.

“Prospectus” shall mean the prospectus included in a Registration Statement (including, without limitation, any preliminary prospectus and any prospectus that includes any information previously omitted from a prospectus filed as part of an effective registration statement in reliance upon Rule 430A promulgated under the Securities Act) and any such Prospectus as amended or supplemented by any prospectus supplement, and all other amendments and supplements to such Prospectus, including post-effective amendments, and in each case including all material incorporated by reference (or deemed to be incorporated by reference) therein.

“Registrable Securities” shall mean (i) the Warrants, (ii) any Warrant Shares issued upon exercise of or pursuant to the Warrants, (iii) any Shares otherwise or hereafter purchased or acquired by the Holders or their Affiliates and (iv) any other securities of the Company (or any successor or assign of the Company, whether by merger, consolidation, sale of assets or otherwise) which may be issued with respect to, in exchange for, or in substitution of, Registrable Securities referenced in clauses (i), (ii) and (iii) above by reason of any divided, distribution or share split, combination of shares, merger, consolidation, recapitalization, reclassification, reorganization, sale of assets or similar transaction. As to any particular Registrable Securities, such securities shall cease to be Registrable Securities when (A) a registration statement with respect to the sale of such securities shall have been declared effective under the Securities Act and such securities shall have been disposed of in accordance with such registration statement, (B) such securities are sold pursuant to Rule 144 (or any similar provisions then in force) under the Securities Act, (C) such securities have been otherwise transferred, a new certificate or other evidence of ownership for them not bearing the legend restricting further transfer shall have been delivered by the Company and subsequent public distribution of them shall not require registration under the Securities Act, (D) such securities shall have ceased to be outstanding, or (E) after February 16, 2009.

“Registration Expenses” shall mean any and all reasonable out of pocket expenses incident to performance of or compliance with this Agreement by the Company and its subsidiaries, including, without limitation (i) all SEC, stock exchange, NASD and other registration, listing and filing fees, (ii) all fees and expenses incurred in connection with compliance with state securities or blue sky laws and compliance with the rules of any stock exchange (including fees and disbursements of counsel in connection with such compliance and the preparation of a blue sky memorandum and legal investment survey), (iii) all printers’ fees and costs incurred in printing, distributing, mailing and delivering any Registration Statement, any Prospectus and any other document relating to the performance of or compliance with this

-3-

Agreement, (iv) the fees and disbursements of counsel for the Company, (v) the fees and disbursements of one Holders’ Counsel, (vi) the fees and disbursements of all independent public accountants (including the expenses of any audit and/or “cold comfort” letters) and the fees and expenses of other Persons, including experts, retained by the Company, (vii) the expenses incurred in connection with making road show presentations and holding meetings with potential investors to facilitate the distribution and sale of Registrable Securities, (viii) any fees and disbursements of underwriters customarily paid by issuers or sellers of securities, (ix) premiums and other costs of policies of insurance against liabilities arising out of the public offering of the Registrable Securities being registered, and (x) all internal expenses of the Company (including all salaries and expenses of officers and employees performing legal or accounting duties); provided, however, Registration Expenses shall not include discounts and commissions payable to underwriters, selling brokers, dealer managers or other similar Persons engaged in the distribution of any of the Registrable Securities; and provided further, that in any case where Registration Expenses are not to be borne by the Company, such expenses shall not include salaries of Company personnel or general overhead expenses of the Company, auditing fees, premiums or other expenses relating to liability insurance required by underwriters of the Company or other expenses for the preparation of financial statements or other data normally prepared by the Company in the ordinary course of its business or which the Company would have incurred in any event; provided, further, that if the Company does not register any securities with respect to which it had given written notice of its intention to register to Holders, notwithstanding anything to the contrary in the foregoing, all of the costs incurred by the Holders in connection with such registration shall be deemed to be Registration Expenses.

“Registration Statement” shall mean any registration statement of the Company which covers any Registrable Securities and all amendments and supplements to any such Registration Statement, including post-effective amendments, in each case including the Prospectus contained therein, all exhibits thereto and all material incorporated by reference (or deemed to be incorporated by reference) therein.

“Request” shall have the meaning set forth in Section 2.1(a).

“SEC” shall mean the Securities and Exchange Commission, or any successor agency having jurisdiction to enforce the Securities Act.

“Securities Act” shall mean the Securities Act of 1933, as amended from time to time, and the rules and regulations thereunder, or any successor statute.

“Shares” shall mean shares in the common stock of the Company.

“Shelf Registration” shall have the meaning set forth in Section 2.1(a).

“Underwriters” shall mean the underwriters, if any, of the offering being registered under the Securities Act.

“Underwritten Offering” shall mean a sale of securities of the Company to an Underwriter or Underwriters for reoffering to the public.

-4-

“Warrant Shares” shall mean the Shares or other securities issued or issuable upon the exercise of the Warrants.

“Warrants” shall mean the warrants issued to the Initial Holder pursuant to the Financing Agreement, together with any additional warrants issued in accordance with the terms thereof.

“Withdrawn Demand Registration” shall have the meaning set forth in Section 2.1(a).

“Withdrawn Request” shall have the meaning set forth in Section 2.1(a).

2. REGISTRATION UNDER THE SECURITIES ACT.

2.1. Demand Registration.

(a) Right to Demand Registration. Subject to Section 2.1(c), at any time after May 17,2004 or from time to time thereafter the Majority Holders shall have the right to request in writing that the Company register all or part of such Holders’ Registrable Securities (a “Request”) (which Request shall specify the amount of Registrable Securities intended to be disposed of by such requesting Holders and the intended method of disposition thereof) by filing with the SEC a Demand Registration Statement. As promptly as practicable, but no later than 15 days after receipt of a Request, the Company shall give written notice of such requested registration to all other Holders of Registrable Securities. Subject to Section 2.1(b), the Company shall include in a Demand Registration (i) the Registrable Securities intended to be disposed of by the Initiating Holders and (ii) the Registrable Securities intended to be disposed of by any other Holder which shall have made a written request (which request shall specify the amount of Registrable Securities to be registered and the intended method of disposition thereof) to the Company for inclusion thereof in such registration within 20 days after the receipt of such written notice from the Company. The Company shall, as expeditiously as possible, following a Request, use its reasonable best efforts to cause to be filed with the SEC a Demand Registration Statement providing for the registration under the Securities Act of the Registrable Securities which the Company has been so requested to register by all such Holders, to the extent necessary to permit the disposition of such Registrable Securities to be registered in accordance with the intended methods of disposition thereof specified in such Request or further requests (including, without limitation, by means of a shelf registration pursuant to Rule 415 under the Securities Act (a “Shelf Registration”) if so requested and if the Company is then eligible to use such a registration). The Company shall use its reasonable best efforts to have such Demand Registration Statement declared effective by the SEC as soon as practicable thereafter and to keep such Demand Registration Statement continuously effective for the period specified in Section 4.1(b).

A Request may be withdrawn prior to the filing of the Demand Registration Statement by the Majority Holders of the Registration (a “Withdrawn Request”) and a Demand Registration Statement may be withdrawn prior to the effectiveness thereof by the Majority Holders of the Registration (a “Withdrawn Demand Registration”), and such withdrawals shall be treated as a Demand Registration which shall have been effected pursuant to this Section 2.1,

-5-

unless the Holders of Registrable Securities to be included in such Registration Statement reimburse the Company for its reasonable out-of-pocket Registration Expenses relating to the preparation and filing of such Demand Registration Statement (to the extent actually incurred), in which case such withdrawal shall not be treated as a Demand Registration effected pursuant to this Section 2.1 (and shall not be counted toward the number of Demand Registrations); provided, however, that if a Withdrawn Request or Withdrawn Registration Statement is made (A) because of a material adverse change in the business, financial condition or prospects of the Company, or (B) because the sole or lead managing Underwriter advises that the amount of Registrable Securities to be sold in such offering be reduced pursuant to Section 2.1(b) by more than 15% of the Registrable Securities to be included in such Registration Statement, then such withdrawal shall not be treated as a Demand Registration effected pursuant to this Section 2.1 (and shall not be counted toward the number of Demand Registrations), and the Company shall pay all Registration Expenses in connection therewith. Any Holder requesting inclusion in a Demand Registration may, at any time prior to the effective date of the Demand Registration Statement (and for any reason) revoke such request by delivering written notice to the Company revoking such requested inclusion.

The registration rights granted pursuant to the provisions of this Section 2.1 shall be in addition to the registration rights granted pursuant to the other provisions of Section 2 hereof.

(b) Priority in Demand Registrations. If a Demand Registration involves an Underwritten Offering, and the sole or lead managing Underwriter, as the case may be, of such Underwritten Offering shall advise the Company in writing (with a copy to each Holder requesting registration) on or before the date five days prior to the date then scheduled for such offering that, in its opinion, the amount of Registrable Securities requested to be included in such Demand Registration exceeds the number which can be sold in such offering within a price range acceptable to the Majority Holders of the Registration (such writing to state the basis of such opinion and the approximate number of Registrable Securities which may be included in such offering), and the Request is not thereafter withdrawn, the Company shall include in such Demand Registration, to the extent of the number which the Company is so advised may be included in such offering, the Registrable Securities requested to be included in the Demand Registration by the Holders allocated pro rata in proportion to the number of Registrable Securities requested to be included in such Demand Registration by each of them. In the event the Company shall not, by virtue of this Section 2.1(b), include in any Demand Registration all of the Registrable Securities of any Holder requested to be included in such Demand Registration, such Holder may, upon written notice to the Company given within five days of the time such Holder first is notified of such matter, further reduce the amount of Registrable Securities it desires to have included in such Demand Registration, whereupon only the Registrable Securities, if any, that it desires to have included will be so included and the Holders not so reducing shall be entitled to a corresponding pro rata increase in the amount of Registrable Securities to be included in such Demand Registration.

(c) Limitations on Registrations. The rights of Holders of Registrable Securities to request Demand Registrations pursuant to Section 2.1(a) are subject to the following limitations: (i) in no event shall the Company be required to effect a Demand Registration after February 16, 2009 and (ii) in no event shall the Company be required to effect,

-6-

in the aggregate, more than 3 Demand Registrations pursuant to this Section 2.1, provided, however, that such number shall be increased to the extent the Company (x) does not include in what would otherwise be the final registration for which the Company is required to pay Registration Expenses the number of Registrable Securities requested to be registered by the Holders by reason of Section 2.1(b) or (y) terminates a Shelf Registration pursuant to Section 2.3 prior to the time that all Registrable Securities covered by such Shelf Registration have been sold.

(d) Underwriting; Selection of Underwriters. Notwithstanding anything to the contrary contained in Section 2.1(a), if the Initiating Holders holding a majority of the Registrable Securities for which registration was requested in the Request so elect, the offering of such Registrable Securities pursuant to such Demand Registration shall be in the form of a firm commitment Underwritten Offering and such Initiating Holders may require that all Persons (including other Holders) participating in such registration sell their Registrable Securities to the Underwriters at the same price and on the same terms of underwriting applicable to the Initiating Holders. If any Demand Registration involves an Underwritten Offering, the sole or managing Underwriters and any additional investment bankers and managers to be used in connection with such registration shall be selected by the Company subject to the approval of the Initiating Holders holding a majority of the Registrable Securities for which registration was requested in the Request (such approval not to be unreasonably withheld or delayed).

(e) Effective Registration Statement; Suspension. A Demand Registration Statement shall not be deemed to have become effective (and the related registration will not be deemed to have been effected) (i) unless it has been declared effective by the SEC and remains effective in compliance with the provisions of the Securities Act with respect to the disposition of all Registrable Securities covered by such Demand Registration Statement for the time period specified in Section 4.1(b), (ii) if the offering of any Registrable Securities pursuant to such Demand Registration Statement is unable to proceed as a result of any stop order, injunction or other order or requirement of the SEC or any other governmental agency or court, or (iii) if, in the case of an Underwritten Offering, the conditions to closing specified in an underwriting agreement to which the Company is a party are not satisfied (other than by the sole reason of any breach or failure by the Holders of Registrable Securities) and are not otherwise waived.

(f) Registration of Other Securities. Whenever the Company shall effect a Demand Registration, no securities other than the Registrable Securities shall be covered by such registration unless the Majority Holders of the Registration shall have consented in writing to the inclusion of such other securities (which consent shall not be unreasonably withheld).

(g) Registration Statement Form. Registrations under this Section 2.1 shall be on such appropriate registration form of the SEC (i) as shall be reasonably selected by the Company, and (ii) which shall be available for the sale of Registrable Securities in accordance with the intended method or methods of disposition specified in the requests for registration. The Company agrees to include in any such Registration Statement all information which any selling Holder, upon advice of counsel, shall reasonably request.

(h) Other Registrations. During the period (i) beginning on the date of a Request and (ii) ending on the date that is 90 days after the date that a Demand Registration

-7-

Statement filed pursuant to such Request has been declared effective by the SEC or, if the Holders shall withdraw such Request or such Demand Registration Statement, on the date of such Withdrawn Request or such Withdrawn Registration Statement, the Company shall not, without the consent of the Majority Holders of the Registration, file a registration statement pertaining to any other securities of the Company.

2.2. Incidental Registration.

(a) Right to Include Registrable Securities. If the Company at any time after May 17, 2004 or from time to time thereafter proposes to register any of its securities under the Securities Act (other than in a registration on Form S-4 or S-8 or any successor form to such forms and other than pursuant to Section 2.1 or 2.3) whether or not pursuant to registration rights granted to other holders of its securities and whether or not for sale for its own account, the Company shall deliver prompt written notice (which notice shall be given at least 15 days prior to such proposed registration) to all Holders of Registrable Securities of its intention to undertake such registration, describing in reasonable detail the proposed registration and distribution (including the anticipated range of the proposed offering price, the class and number of securities proposed to be registered and the distribution arrangements) and of such Holders’ right to participate in such registration under this Section 2.2 as hereinafter provided. Subject to the other provisions of this paragraph (a) and Section 2.2(b), upon the written request of any Holder made within 15 days after the receipt of such written notice (which request shall specify the amount of Registrable Securities to be registered and the intended method of disposition thereof), the Company shall effect the registration under the Securities Act of all Registrable Securities requested by Holders to be so registered (an “Incidental Registration”), to the extent required to permit the disposition (in accordance with the intended methods thereof as aforesaid) of the Registrable Securities so to be registered, by inclusion of such Registrable Securities in the Registration Statement which covers the securities which the Company proposes to register and shall cause such Registration Statement to become and remain effective with respect to such Registrable Securities in accordance with the registration procedures set forth in Section 4. If an Incidental Registration involves an Underwritten Offering, promptly after notification to the Company from the Underwriter of the price at which such securities are to be sold, the Company shall so advise each participating Holder. The Holders requesting inclusion in an Incidental Registration may, at any time prior to the effective date of the Incidental Registration Statement (and for any reason), revoke such request by delivering written notice to the Company revoking such requested inclusion.

If at any time after giving written notice of its intention to register any securities and prior to the effective date of the Incidental Registration Statement filed in connection with such registration, the Company shall determine for any reason not to register or to delay registration of such securities, the Company may, at its election, give written notice of such determination to each Holder of Registrable Securities and, thereupon, (A) in the case of a determination not to register, the Company shall be relieved of its obligation to register any Registrable Securities in connection with such registration (but not from its obligation to pay the Registration Expenses incurred in connection therewith), without prejudice, however, to the rights of Holders to cause such registration to be effected as a registration under Section 2.1 or 2.3(a) and (B) in the case of a determination to delay such registration, the Company shall be permitted to delay the registration of such Registrable Securities for the same period as the delay

-8-

in registering such other securities; provided, however, that if such delay shall extend beyond 120 days from the date the Company received a request to include Registrable Securities in such Incidental Registration, then the Company shall again give all Holders the opportunity to participate therein and shall follow the notification procedures set forth in the preceding paragraph. There is no limitation on the number of such Incidental Registrations pursuant to this Section 2.2 which the Company is obligated to effect.

The registration rights granted pursuant to the provisions of this Section 2.2 shall be in addition to the registration rights granted pursuant to the other provisions of Section 2 hereof.

(b) Priority in Incidental Registration. If an Incidental Registration involves an Underwritten Offering (on a firm commitment basis), and the sole or the lead managing Underwriter, as the case may be, of such Underwritten Offering shall advise the Company in writing (with a copy to each Holder requesting registration) on or before the date five days prior to the date then scheduled for such offering that, in its opinion, the amount of securities (including Registrable Securities) requested to be included in such registration exceeds the amount which can be sold in such offering without materially interfering with the successful marketing of the securities being offered (such writing to state the basis of such opinion and the approximate number of such securities which may be included in such offering without such effect), the Company shall include in such registration, to the extent of the number which the Company is so advised may be included in such offering without such effect, (i) in the case of a registration initiated by the Company, (A) first, the securities that the Company proposes to register for its own account (but solely to the extent that the proceeds thereof shall not be used to purchase shares of common stock of the Company or other securities of the Company), (B) second, the Registrable Securities requested to be included in such registration by the Holders, allocated pro rata in proportion to the number of Registrable Securities requested to be included in such registration by each of them, and (C) third, other securities of the Company to be registered on behalf of any other Person, and (ii) in the case of a registration initiated by a Person other than the Company, (A) first, the Registrable Securities requested to be included in such registration by any Persons initiating such registration requested to be included in such registration by any Persons initiating such registration, (B) second, the Registrable Securities requested to be included in such registration by the Holders and any other Persons (not including Affiliates of the Company), allocated pro rata in proportion to the number of securities requested to be included in such registration by each of them, and (C) third, the securities that the Company proposes to register for the account of it and its Affiliates, provided, however, that in the event the Company will not, by virtue of this Section 2.2(b), include in any such registration all of the Registrable Securities of any Holder requested to be included in such registration, such Holder may, upon written notice to the Company given within three days of the time such Holder first is notified of such matter, reduce the amount of Registrable Securities it desires to have included in such registration, whereupon only the Registrable Securities, if any, it desires to have included will be so included and the Holders not so reducing shall be entitled to a corresponding pro rata increase in the amount of Registrable Securities to be included in such registration.

-9-

2.3. S-3 Registration; Shelf Registration.

S-3 Registration. If at any time after May 17, 2004 (i) the Majority Holder(s) request that the Company file a registration statement on S-3 or any successor form thereto for a public offering of all of the Registrable Securities, and (ii) the Company is a registrant entitled to use S-3 or any successor form thereto to register such securities, then the Company shall, as expeditiously as possible following such Request, use its reasonable best efforts to register under the Securities Act on S-3 or any successor form thereto, for public sale in accordance with the intended methods of disposition specified in such Request or any subsequent requests (including, without limitation, by means of a Shelf Registration) all of the Registrable Securities; provided, that if such registration is for an Underwritten Offering, the terms of Sections 2.1(b) and 2.1(d) shall apply (and any reference to “Demand Registration” therein shall, for purposes of this Section 2.3, instead be deemed a reference to “S-3 Registration”). Whenever the Company is required by this Section 2.3 to use its reasonable best efforts to effect the registration of Registrable Securities, each of the procedures and requirements of Section 2.1(a) and 2.1(e) (including but not limited to the requirements that the Company (A) notify all Holders of Registrable Securities from whom such Request for registration has not been received and provide them with the opportunity to participate in the offering and (B) use its reasonable best efforts to have such S-3 Registration Statement declared and remain effective for the time period specified herein) shall apply to such registration (and any reference in such Sections 2.1(a) and 2.1(e) to “Demand Registration” shall, for purposes of this Section 2.3, instead be deemed a reference to “S-3 Registration”). Notwithstanding anything to the contrary contained herein, no Request may be made under this Section 2.3 within 90 days after the effective date of a Registration Statement filed by the Company covering a firm commitment Underwritten Offering in which the Holders of Registrable Securities shall have been entitled to join pursuant to this Agreement in which there shall have been effectively registered all shares or units of Registrable Securities as to which registration shall have been requested. There is no limitation on the number of S-3 Registrations that the Company is obligated to effect.

The Company shall include as selling securityholders under the S-3 Registration Statement all Holders of Registrable Securities who request in accordance with the procedures herein to be so included, and (by filing a prospectus supplement or supplements, if required by law or SEC rules) such other Holders of Registrable Securities that so request from time to time after the effectiveness of such S-3 Registration Statement, in each case after such Holder provides to the Company such information as the Company shall request in accordance with Section 4.2.

The registration rights granted pursuant to the provisions of this Section 2.3(a) shall be in addition to the registration rights granted pursuant to the other provisions of this Section 2; provided, however, that if a S-3 Registration Statement has been filed and is effective with respect to any Registrable Securities, the Company may satisfy its obligations with respect to a demand registration with respect to such Registrable Securities by utilizing such S-3 Registration Statement if the offer and sale of such Registrable Securities can be accomplished thereunder.

(a) Shelf Registration. If a request made pursuant to Section 2.1 or 2.3(a) is for a Shelf Registration, the Company shall use its reasonable best efforts to keep the Shelf Registration continuously effective through the date on which all of the Registrable Securities covered by such Shelf Registration may be sold pursuant to Rule 144(k) under the Securities Act

-10-

(or any successor provision having similar effect); provided, however, that prior to the termination of such Shelf Registration, the Company shall first furnish to each Holder of Registrable Securities participating in such Shelf Registration (i) an opinion, in form and substance satisfactory to the Majority Holders of the Registration, of counsel for the Company satisfactory to the Majority Holders of the Registration stating that such Registrable Securities are freely saleable pursuant to Rule 144(k) under the Securities Act (or any successor provision having similar effect) or (ii) a “No-Action Letter” from the staff of the SEC stating that the SEC would not recommend enforcement action if the Registrable Securities included in such Shelf Registration were sold in a public sale other than pursuant to an effective registration statement.

2.4. Underwritten Offerings .

(a) Demand Underwritten Offerings. If requested by the sole or lead managing Underwriter for any Underwritten Offering effected pursuant to a Demand Registration or an F-3 or S-3 Registration, the Company shall enter into a customary underwriting agreement with the Underwriters for such offering, such agreement to be reasonably satisfactory in substance and form to the Company and each Holder of Registrable Securities participating in such offering and to contain such representations and warranties by the Company and such other terms as are generally prevailing in agreements of that type, including, without limitation, indemnification and contribution to the effect and to the extent provided in Section 5.

(b) Holders of Registrable Securities to be Parties to Underwriting Agreement. The Holders of Registrable Securities to be distributed by Underwriters in an Underwritten Offering contemplated by Section 2 shall be parties to the underwriting agreement between the Company and such Underwriters and may, at such Holders’ option, require that any or all of the representations and warranties by, and the other agreements on the part of, the Company to and for the benefit of such Underwriters shall also be made to and for the benefit of such Holders of Registrable Securities and that any or all of the conditions precedent to the obligations of such Underwriters under such underwriting agreement be conditions precedent to the obligations of such Holders of Registrable Securities; provided, however, that the Company shall not be required to make any representations or warranties with respect to written information specifically provided by a selling Holder for inclusion in the Registration Statement. No Holder shall be required to make any representations or warranties to, or agreements with, the Company or (in the case of an Incidental Registration) the Underwriters other than representations, warranties or agreements regarding such Holder, such Holder’s Registrable Securities and such Holder’s intended method of disposition.

(c) Participation in Underwritten Registration. Notwithstanding anything herein to the contrary, no Person may participate in any underwritten registration hereunder unless such Person (i) agrees to sell its securities on the same terms and conditions provided in any underwriting arrangements approved by the Persons entitled hereunder to approve such arrangement and (ii) accurately completes and executes in a timely manner all questionnaires, powers of attorney, indemnities, custody agreements, underwriting agreements and other documents reasonably required under the terms of such underwriting arrangements.

2.5. Expenses. Except as stated herein, the Company shall pay all Registration Expenses in connection with any Demand Registration, Incidental Registration, F-3 or S-3

-11-

Registration or Shelf Registration whether or not such registration shall become effective and whether or not all Registrable Securities originally requested to be included in such registration are withdrawn or otherwise ultimately not included in such registration, except as otherwise provided with respect to a Withdrawn Request and a Withdrawn Demand Registration in Section 2.1(a).

2.6. Postponements.The Company shall be entitled to postpone a Demand Registration and an F-3 or S-3 Registration and to require the Holders of Registrable Securities to discontinue the disposition of their securities covered by a Shelf Registration during any Blackout Period (as defined below) (i) if the Board of Directors of the Company determines in good faith that effecting such a registration or continuing such disposition at such time would have a material adverse effect upon a proposed sale of all (or substantially all) of the assets of the Company or a merger, reorganization, recapitalization or similar current transaction materially affecting the capital structure or equity ownership of the Company, or (ii) if the Company is in possession of material information which the Board of Directors of the Company determines in good faith it is not in the best interests of the Company to disclose in a registration statement at such time; provided, however, that the Company may only delay a Demand Registration or an F-3 or S-3 Registration pursuant to this Section 2.6 by delivery of a Blackout Notice (as defined below) within 10 days of delivery of the request for such Registration under Section 2.1 or Section 2.3, as applicable, and may delay a Demand Registration or an F-3 or S-3 Registration and require the Holders of Registrable Securities to discontinue the disposition of their securities covered by a Shelf Registration only for a reasonable period of time not to exceed 45 days (or such earlier time as such transaction is consummated or no longer proposed or the material information has been made public) (the “Blackout Period”). There shall not be more than one Blackout Period in any 12 month period. The Company shall promptly notify the Holders in writing (a “Blackout Notice”) of any decision to postpone a Demand Registration or an F-3 or S-3 Registration or to discontinue sales of Registrable Securities covered by a Shelf Registration pursuant to this Section 2.6 and shall include a general statement of the reason for such postponement, an approximation of the anticipated delay and an undertaking by the Company promptly to notify the Holders as soon as a Demand Registration or an F-3 or S-3 Registration may be effected or sales of Registrable Securities covered by a Shelf Registration may resume. In making any such determination to initiate or terminate a Blackout Period, the Company shall not be required to consult with or obtain the consent of any Holder, and any such determination shall be the Company’s sole responsibility. Each Holder shall treat all notices received from the Company pursuant to this Section 2.6 in the strictest confidence and shall not disseminate such information. If the Company shall postpone the filing of a Demand Registration Statement or an F-3 or S-3 Registration Statement, the Majority Holders who were to participate therein shall have the right to withdraw the request for registration. Any such withdrawal shall be made by giving written notice to the Company within 10 days after receipt of the Blackout Notice. Such withdrawn registration request shall not be treated as a Demand Registration effected pursuant to Section 2.1 (and shall not be counted towards the number of Demand Registrations effected pursuant to Section 2.1(c)), and the Company shall pay all Registration Expenses in connection therewith.

-12-

3. HOLDBACK ARRANGEMENTS.

3.1. Restrictions on Sale by Holders of Registrable Securities. Each Holder of Registrable Securities agrees, by acquisition of such Registrable Securities, if timely requested in writing by the sole or lead managing Underwriter, not to make any short sale of, loan, grant any option for the purchase of or effect any sale or distribution, of any of the Company’s equity securities (or any security convertible into or exchangeable or exercisable for any of the Company’s equity securities) during the nine business days (as such term is used in Regulation M under the Exchange Act) prior to, and during the time period reasonably requested by the sole or lead managing Underwriter not to exceed 90 days, beginning on the effective date of the applicable registration statement (except as part of such underwritten registration or pursuant to registrations on Forms S-4 or S-8 or any successor form to such forms), unless the sole or lead Managing Underwriter in such Underwritten Offering otherwise agrees.

3.2. Restrictions on Sale by the Company and Others. The Company agrees that if timely requested in writing by the sole or lead managing Underwriter in an Underwritten Offering of any Registrable Securities, not to make any short sale of, loan, grant any option for the purchase of or effect any sale or distribution of any of the Company’s equity securities (or any security convertible into or exchangeable or exercisable for any of the Company’s equity securities) during the nine business days (as such term is used in Regulation M under the Exchange Act) prior to, and during the time period reasonably requested by the sole or lead managing Underwriter not to exceed 90 days, beginning on the effective date of the applicable registration statement (except as part of such underwritten registration or pursuant to registrations on Forms S-4 or S-8 or any successor form to such forms), unless the sole or lead Managing Underwriter in such Underwritten Offering otherwise agrees. The Company will use its reasonable best efforts to cause each director or officer of the Company and each holder of 5% or more of the equity securities (or any security convertible into or exchangeable or exercisable for any of its equity securities) of the Company purchased from the Company at any time after the date of this Agreement (other than in a registered public offering or in a public sale) to so agree.

4. REGISTRATION PROCEDURES.

4.1. Obligations of the Company. Whenever the Company is required to effect the registration of Registrable Securities under the Securities Act pursuant to Section 2 of this Agreement, the Company shall use commercially reasonable efforts to, as expeditiously as practicable:

(a) prepare and file with the SEC (promptly, and in any event within 60 days after receipt of a request to register Registrable Securities) the requisite Registration Statement to effect such registration, which Registration Statement shall comply as to form in all material respects with the requirements of the applicable form and include all financial statements required by the SEC to be filed therewith, and the Company shall use its reasonable best efforts to cause such Registration Statement to become effective (provided, that the Company may discontinue any registration of its securities that are not Registrable Securities, and, under the circumstances specified in Section 2.2, its securities that are Registrable Securities); provided, however, that before filing a Registration Statement or Prospectus or any amendments or

-13-

supplements thereto, or comparable statements under securities or blue sky laws of any jurisdiction, the Company shall (i) provide Holders’ Counsel and any other Inspector (as defined below) with an adequate and appropriate opportunity to participate in the preparation of such Registration Statement and each Prospectus included therein (and each amendment or supplement thereto or comparable statement) to be filed with the SEC, which documents shall be subject to the review and comment of Holders’ Counsel, and (ii) not file any such Registration Statement or Prospectus (or amendment or supplement thereto or comparable statement) with the SEC to which Holder’s Counsel, any selling Holder or any other Inspector shall have reasonably objected on the grounds that such filing does not comply in all material respects with the requirements of the Securities Act or of the rules or regulations thereunder;

(b) prepare and file with the SEC such amendments and supplements to such Registration Statement and the Prospectus used in connection therewith as may be necessary (i) to keep such Registration Statement effective during the periods required herein, and (ii) to comply with the provisions of the Securities Act with respect to the disposition of all Registrable Securities covered by such Registration Statement, in each case until such time as all of such Registrable Securities have been disposed of in accordance with the intended methods of disposition by the seller(s) thereof set forth in such Registration Statement; provided that except with respect to any Shelf Registration, such period need not extend beyond twelve months after the effective date of the Registration Statement; and provided further, that with respect to any Shelf Registration, such period need not extend beyond the time period provided in Section 2.3, and which periods, in any event, shall terminate when all Registrable Securities covered by such Registration Statement have been sold or have otherwise ceased to be Registrable Securities (but not before the expiration of the applicable period referred to in Section 4(3) of the Securities Act and Rule 174 thereunder, if applicable);

(c) furnish, without charge, to each selling Holder of such Registrable Securities and each Underwriter, if any, of the securities covered by such Registration Statement, such number of copies of such Registration Statement, each amendment and supplement thereto (in each case including all exhibits), and the Prospectus included in such Registration Statement (including each preliminary Prospectus) in conformity with the requirements of the Securities Act, and other documents, as such selling Holder and Underwriter may reasonably request in order to facilitate the public sale or other disposition of the Registrable Securities owned by such selling Holder (the Company hereby consenting to the use in accordance with applicable law of each such Registration Statement (or amendment or post-effective amendment thereto) and each such Prospectus (or preliminary prospectus or supplement thereto) by each such selling Holder of Registrable Securities and the Underwriters, if any, in connection with the offering and sale of the Registrable Securities covered by such Registration Statement or Prospectus);

(d) prior to any public offering of Registrable Securities, use its commercially reasonable efforts to register or qualify all Registrable Securities and other securities covered by such Registration Statement under such other securities or blue sky laws of such jurisdictions as any selling Holder of Registrable Securities covered by such Registration Statement or the sole or lead managing Underwriter, if any, may reasonably request to enable such selling Holder to consummate the disposition in such jurisdictions of the Registrable Securities owned by such selling Holder and to continue such registration or qualification in effect in each such jurisdiction for as long as such Registration Statement remains in effect (including through new filings or

-14-

amendments or renewals), and do any and all other acts and things which may be necessary or advisable to enable any such selling Holder to consummate the disposition in such jurisdictions of the Registrable Securities owned by such selling Holder; provided, however, that the Company shall not be required to consent to general service of process in any such jurisdiction;

(e) use its commercially reasonable efforts to obtain all other approvals, consents, exemptions or authorizations from such governmental agencies or authorities as may be necessary to enable the selling Holders of such Registrable Securities to consummate the disposition of such Registrable Securities;

(f) notify Holders’ Counsel, each Holder of Registrable Securities covered by such Registration Statement and the sole or lead managing Underwriter, if any: (i) when the Registration Statement, any pre-effective amendment, the Prospectus or any prospectus supplement related thereto or post-effective amendment to the Registration Statement has been filed and, with respect to the Registration Statement or any post-effective amendment, when the same has become effective, (ii) of any request by the SEC or any state securities or blue sky authority for amendments or supplements to the Registration Statement or the Prospectus related thereto or for additional information, (iii) of the issuance by the SEC of any stop order suspending the effectiveness of the Registration Statement or the initiation or threat of any proceedings for that purpose, (iv) of the receipt by the Company of any notification with respect to the suspension of the qualification of any Registrable Securities for sale under the securities or blue sky laws of any jurisdiction or the initiation of any proceeding for such purpose, (v) of the existence of any fact of which the Company becomes aware or the happening of any event which results in (A) the Registration Statement containing an untrue statement of a material fact or omitting to state a material fact required to be stated therein or necessary to make any statements therein not misleading, or (B) the Prospectus included in such Registration Statement containing an untrue statement of a material fact or omitting to state a material fact required to be stated therein or necessary to make any statements therein, in the light of the circumstances under which they were made, not misleading, (vi) if at any time the representations and warranties contained in any underwriting agreement in respect of such offering cease to be true and correct in all material respects, and (vii) of the Company’s reasonable determination that a post-effective amendment to a Registration Statement would be appropriate or that there exists circumstances not yet disclosed to the public which make further sales under such Registration Statement inadvisable pending such disclosure and post-effective amendment; and, if the notification relates to an event described in any of the clauses (ii) through (vii) of this Section 4.1(f), (1) each Holder agrees that such Holder will immediately discontinue disposition of Registrable Securities pursuant to any Registration Statement(s) covering such Registrable Securities until such Holder’s receipt of the copies of the supplemented or amended prospectus contemplated below or receipt of notice that no supplement or amendment is required; provided, that nothing herein shall prevent any Holder, in connection with any sale of Registrable Securities with respect to which a Holder has entered into a contract for sale prior to the Holder’s receipt of a notice from the Company hereunder and for which the Holder has not yet settled, from settling such sale and delivering unlegended shares, if applicable, and (2) the Company shall promptly prepare a supplement or post-effective amendment to such Registration Statement or related Prospectus or any document incorporated therein by reference or file any other required document so that (1) such Registration Statement shall not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the

-15-

statements therein not misleading, and (2) as thereafter delivered to the purchasers of the Registrable Securities being sold thereunder, such Prospectus shall not include an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein in the light of the circumstances under which they were made not misleading (and shall furnish to each such Holder and each Underwriter, if any, a reasonable number of copies of such Prospectus so supplemented or amended); and if the notification relates to an event described in clause (iii) of this Section 4.1(f), the Company shall take all reasonable action required to prevent the entry of such stop order or to remove it if entered;

(g) make available for inspection by any selling Holder of Registrable Securities, any sole or lead managing Underwriter participating in any disposition pursuant to such Registration Statement, Holders’ Counsel and any attorney, accountant or other agent retained by any such seller or any Underwriter (each, an “Inspector” and, collectively, the “Inspectors”), all financial and other records, pertinent corporate documents and properties of the Company and any subsidiaries thereof as may be in existence at such time (collectively, the “Records”) as shall be necessary, in the opinion of such Holders’ and such Underwriters’ respective counsel, to enable them to exercise their due diligence responsibility and to conduct a reasonable investigation within the meaning of the Securities Act, and cause the Company’s and any subsidiaries’ officers, directors and employees, and the independent public accountants of the Company, to supply all information reasonably requested by any such Inspectors in connection with such Registration Statement;

(h) if such registration involves an Underwritten Offering, obtain an opinion from the Company’s counsel and a “cold comfort” letter from the Company’s independent public accountants who have certified the Company’s audited financial statements included or incorporated by reference in such Registration Statement, dated the date of the closing under the underwriting agreement), in customary form and covering such matters as are customarily covered by such opinions and “cold comfort” letters delivered to underwriters in underwritten public offerings, which opinion and letter shall be reasonably satisfactory to the sole or lead managing Underwriter, if any, and to the Majority Holders of the Registration, and furnish to each Holder participating in the offering and to each Underwriter, if any, a copy of such opinion and letter addressed to such Holder (in the case of the opinion) and Underwriter (in the case of the opinion and the “cold comfort” letter);

(i) provide a CUSIP number for all Registrable Securities and provide and cause to be maintained a transfer agent and registrar for all such Registrable Securities covered by such Registration Statement not later than the effectiveness of such Registration Statement;

(j) otherwise use its commercially reasonable efforts to comply with all applicable rules and regulations of the SEC and any other governmental agency or authority having jurisdiction over the offering, and make available to its security holders, as soon as reasonably practicable but no later than 90 days after the end of any 12-month period, an earnings statement (i) commencing at the end of any month in which Registrable Securities are sold to Underwriters in an Underwritten Offering and (ii) commencing with the first day of the Company’s calendar month next succeeding each sale of Registrable Securities after the effective date of a Registration Statement, which statement shall cover such 12-month periods, in a

-16-

manner which satisfies the provisions of Section 11(a) of the Securities Act and Rule 158 thereunder;

(k) use its commercially reasonable efforts to cause all such Registrable Securities to be duly included for quotation on the Nasdaq Stock Market’s National Market (the “Nasdaq National Market”) if the Company’s securities of such class are at the time included on the Nasdaq National Market or listed on the principal national securities exchange on which the Company’s securities of such class are then listed, if applicable;

(l) enter into and perform customary agreements (including, if applicable, an underwriting agreement in customary form) and provide officers’ certificates and other customary closing documents;

(m) cooperate with each selling Holder of Registrable Securities and each Underwriter participating in the disposition of such Registrable Securities and their respective counsel in connection with any filings required to be made with the NASD and make reasonably available its employees and personnel and otherwise provide reasonable assistance to the Underwriters (taking into account the needs of the Company’s businesses and the requirements of the marketing process) in the marketing of Registrable Securities in any Underwritten Offering;

(n) cooperate with the selling Holders of Registrable Securities and the sole or lead managing Underwriter, if any, to facilitate the timely preparation and delivery of certificates not bearing any restrictive legends representing the Registrable Securities to be sold, and cause such Registrable Securities to be issued in such denominations and registered in such names in accordance with the underwriting agreement prior to any sale of Registrable Securities to the Underwriters or, if not an Underwritten Offering, in accordance with the instructions of the selling Holders of Registrable Securities at least three business days prior to any sale of Registrable Securities;

(o) keep each selling Holder of Registrable Securities advised in writing as to the initiation and progress of any registration under Section 2 hereunder;

(p) upon written request, furnish to each Holder participating in the offering and the sole or lead managing Underwriter, if any, without charge, at least one manually-signed copy of the Registration Statement and any post-effective amendments thereto, including financial statements and schedules, all documents incorporated therein by reference and all exhibits (including those deemed to be incorporated by reference);

(q) if requested by the sole or lead managing Underwriter or any selling Holder of Registrable Securities, promptly incorporate in a prospectus supplement or post-effective amendment such information concerning such Holder of Registrable Securities, the Underwriters or the intended method of distribution as the sole or lead managing Underwriter or the selling Holder of Registrable Securities reasonably requests to be included therein and as is appropriate in the reasonable judgment of the Company, including, without limitation, information with respect to the number of shares of the Registrable Securities being sold to the Underwriters, the purchase price being paid therefor by such Underwriters and with respect to any other terms of the Underwritten Offering of the Registrable Securities to be sold in such offering; make all

-17-

required filings of such Prospectus supplement or post-effective amendment as soon as notified of the matters to be incorporated in such Prospectus supplement or post-effective amendment; and supplement or make amendments to any Registration Statement if requested by the sole or lead managing Underwriter of such Registrable Securities; and

(r) use its commercially reasonable efforts to take all other steps necessary to expedite or facilitate the registration and disposition of the Registrable Securities contemplated hereby.

4.2. Seller Information. The Company may require each selling Holder of Registrable Securities as to which any registration is being effected to furnish to the Company such information regarding such seller and the disposition of such securities as the Company may from time to time reasonably request in writing; provided, however, that such information shall be used only in connection with such Registration. If any Registration Statement or comparable statement under “blue sky” laws refers to any Holder by name or otherwise as the Holder of any securities of the Company, then such Holder shall have the right to require (i) the insertion therein of language, in form and substance satisfactory to such Holder and the Company, to the effect that the holding by such Holder of such securities is not to be construed as a recommendation by such Holder of the investment quality of the Company’s securities covered thereby and that such holding does not imply that such Holder will assist in meeting any future financial requirements of the Company, and (ii) in the event that such reference to such Holder by name or otherwise is not in the judgment of the Company, as advised by counsel, required by the Securities Act or any similar federal statute or any state “blue sky” or securities law then in force, the deletion of the reference to such Holder.

4.3. Notice to Discontinue. Each Holder of Registrable Securities agrees by acquisition of such Registrable Securities that, (i) upon receipt of any notice from the Company of the happening of any event of the kind described in Section 4.1(f)(ii) through 4.1(f)(vii), such Holder shall forthwith discontinue disposition of Registrable Securities pursuant to the Registration Statement covering such Registrable Securities until such Holder’s receipt of the copies of the supplemented or amended prospectus contemplated by Section 4.1(f) and, if so directed by the Company, such Holder shall deliver to the Company (at the Company’s expense) all copies, other than permanent file copies, then in such Holder’s possession of the Prospectus covering such Registrable Securities which is current at the time of receipt of such notice. If the Company shall give any such notice, the Company shall extend the period during which such Registration Statement shall be maintained effective pursuant to this Agreement (including, without limitation, the period referred to in Section 4.1(b)) by the number of days during the period from and including the date of the giving of such notice pursuant to Section 4.1(f) to and including the date when the Holder shall have received the copies of the supplemented or amended prospectus contemplated by and meeting the requirements of Section 4.1(f).

5. INDEMNIFICATION; CONTRIBUTION.

5.1. Indemnification by the Company. The Company agrees to indemnify and hold harmless, to the fullest extent permitted by law, each Holder of Registrable Securities, its officers, directors, partners, members, shareholders, employees, Affiliates, advisers, attorneys and agents (collectively, “Agents”) and each Person who controls such Holder (within the

-18-

meaning of the Securities Act) and its Agents with respect to each registration which has been effected pursuant to this Agreement, against any and all losses, claims, damages or liabilities, joint or several, actions or proceedings (whether commenced or threatened) in respect thereof, and expenses (as incurred or suffered and including, but not limited to, any and all expenses incurred in investigating, preparing or defending any litigation or proceeding, whether commenced or threatened, and the reasonable fees, disbursements and other charges of legal counsel) in respect thereof (collectively, “Claims”), insofar as such Claims arise out of or are based upon any untrue or alleged untrue statement of a material fact contained in any Registration Statement or Prospectus (including any preliminary, final or summary prospectus and any amendment or supplement thereto) related to any such registration or any omission or alleged omission to state a material fact required to be stated therein or necessary to make the statements therein not misleading, or any violation by the Company of the Securities Act or any rule or regulation thereunder applicable to the Company and relating to action or inaction required of the Company in connection with any such registration, or any qualification or compliance incident thereto; provided, however, that the Company will not be liable in any such case to the extent that any such Claims arise out of or are based upon any untrue statement or alleged untrue statement of a material fact or omission or alleged omission of a material fact so made in reliance upon and in conformity with written information furnished to the Company by a Holder, Underwriter or other indemnified person hereunder expressly for use therein. The Company shall also agree to indemnify any Underwriters of the Registrable Securities, their Agents and each Person who controls any such Underwriter (within the meaning of the Securities Act) to the same extent as provided above with respect to the indemnification of the Holders of Registrable Securities. Such indemnity shall remain in full force and effect regardless of any investigation made by or on behalf of any Person who may be entitled to indemnification pursuant to this Section 5 and shall survive the transfer of securities by such Holder or Underwriter.

5.2. Indemnification by Holders. Each Holder, if Registrable Securities held by it are included in the securities as to which a registration is being effected, agrees to, severally and not jointly, indemnify and hold harmless, to the fullest extent permitted by law, the Company, its directors and officers, each other Person who participates as an Underwriter in the offering or sale of such securities and its Agents and each Person who controls the Company against any and all Claims, insofar as such Claims arise out of or are based upon any untrue or alleged untrue statement of a material fact contained in any Registration Statement or Prospectus (including any preliminary, final or summary prospectus and any amendment or supplement thereto) related to such registration, or any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in reliance upon and in conformity with written information furnished to the Company by a Holder, Underwriter or other indemnified person hereunder expressly for use therein, or any violation by such Holder of the Securities Act or any rule or regulation thereunder applicable to such Holder and relating solely to action or inaction solely caused by such Holder as required by such Holder in connection with any such registration, or any qualification or compliance incident thereto; provided, however, that the aggregate amount which any such Holder shall be required to pay pursuant to this Section 5.2 shall in no event be greater than the amount of the net proceeds received by such Holder upon the sale of the Registrable Securities pursuant to the Registration Statement giving rise to such

-19-

Claims less all amounts previously paid by such Holder with respect to any such Claims. Such indemnity shall remain in full force and effect regardless of any investigation made by or on behalf of any Person who may be entitled to indemnification pursuant to this Section 5 and shall survive the transfer of securities by such Holder or Underwriter.

5.3. Conduct of Indemnification Proceedings. Promptly after receipt by an indemnified party of notice of any Claim or the commencement of any action or proceeding involving a Claim under this Section 5, such indemnified party shall, if a claim in respect thereof is to be made against the indemnifying party pursuant to Section 5, (i) notify the indemnifying party in writing of the Claim or the commencement of such action or proceeding; provided, that the failure of any indemnified party to provide such notice shall not relieve the indemnifying party of its obligations under this Section 5, except to the extent the indemnifying party is materially and actually prejudiced thereby and shall not relieve the indemnifying party from any liability which it may have to any indemnified party otherwise than under this Section 5, and (ii) permit such indemnifying party to assume the defense of such claim with counsel reasonably satisfactory to the indemnified party; provided, however, that any indemnified party shall have the right to employ separate counsel and to participate in the defense of such claim, but the fees and expenses of such counsel shall be at the expense of such indemnified party unless (A) the indemnifying party has agreed in writing to pay such fees and expenses, (B) the indemnifying party shall have failed to assume the defense of such claim and employ counsel reasonably satisfactory to such indemnified party within 20 days after receiving notice from such indemnified party that the indemnified party believes it has failed to do so, or (C) in the reasonable judgment of any such indemnified party, based upon advice of counsel, a conflict of interest shall exist between such indemnified party and the indemnifying party with respect to such claims; it being understood, however, that the indemnifying party shall not, in connection with any one such action or separate but substantially similar or related actions in the same jurisdiction arising out of the same general allegations or circumstances, be liable for the reasonable fees and expenses of more than one separate firm of attorneys (in addition to no more than one firm of local counsel) at any time for all such indemnified parties. No indemnifying party shall be liable for any settlement of any such claim or action effected without its written consent, which consent shall not be unreasonably withheld. No indemnifying party shall, without the consent of the indemnified party, which consent shall not be unreasonably withheld, consent to entry of any judgment or enter into any settlement of any claim or action in respect of which indemnification or contribution may be sought hereunder, unless such settlement, (i) includes an unconditional release of the indemnified party from all liability arising out of such action or claim, (ii) does not include a statement as to or an admission of fault, culpability or a failure to act, by or on behalf of any indemnified party, and (3) does not provide for any action on the part of any party other than the payment of money damages which is to be paid in full by the indemnifying party.

5.4. Contribution. If the indemnification provided for in Section 5.1 or 5.2 from the indemnifying party for any reason is unavailable to (other than by reason of exceptions provided therein), or is insufficient to hold harmless an indemnified party hereunder in respect of any Claim, then the indemnifying party, in lieu of indemnifying such indemnified party, shall contribute to the amount paid or payable by such indemnified party as a result of such Claim in such proportion as is appropriate to reflect the relative fault of the indemnifying party, on the one hand, and the indemnified party, on the other hand, in connection with the actions which resulted

-20-

in such Claim, as well as any other relevant equitable considerations. The relative fault of such indemnifying party and indemnified party shall be determined by reference to, among other things, whether any action in question, including any untrue or alleged untrue statement of a material fact or omission or alleged omission to state a material fact, has been made by, or relates to information supplied by, such indemnifying party or indemnified party, and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such action. If, however, the foregoing allocation is not permitted by applicable law, then each indemnifying party shall contribute to the amount paid or payable by such indemnified party in such proportion as is appropriate to reflect not only such relative faults but also the relative benefits of the indemnifying party and the indemnified party as well as any other relevant equitable considerations.

5.5. Other Indemnification. Indemnification similar to that specified in the preceding Sections 5.1 and 5.2 (with appropriate modifications) shall be given by the Company and each selling Holder of Registrable Securities with respect to any required registration or other qualification of securities under any Federal or state law or regulation of any governmental authority, other than the Securities Act. The indemnity agreements contained herein shall be in addition to any other rights to indemnification or contribution which any indemnified party may have pursuant to law or contract.

5.6. Indemnification Payments. The indemnification and contribution required by this Section 5 shall be made by periodic payments of the amount thereof during the course of any investigation or defense, as and when bills are received or any expense, loss, damage or liability is incurred.

6. General.

6.1. Adjustments Affecting Registrable Securities. The Company agrees that it shall not effect or permit to occur any combination or subdivision of shares or other securities that would adversely affect the ability of the Holder of any Registrable Securities to include such Registrable Securities in any registration contemplated by this Agreement or the marketability of such Registrable Securities in any such registration.

6.2. Registration Rights to Others. The Company represents and warrants that it is not currently a party to any agreement with respect to its securities granting registration rights to Persons other than the Holders. If the Company shall at any time hereafter provide to any holder of any securities of the Company rights with respect to the registration of such securities under the Securities Act (not including any such rights which have been previously granted), without the prior written consent of the Majority Holders, (i) such rights shall not be in conflict with or adversely affect any of the rights provided in this Agreement to the Holders and (ii) if such rights are provided on terms or conditions more favorable to such holder than the terms and conditions provided in this Agreement, the Company shall provide (by way of amendment to this Agreement or otherwise) such more favorable terms or conditions to the Holders.

6.3. Availability of Information; Rule 144; Rule 144A; Other Exemptions. So long as the Company shall not have filed a registration statement pursuant to Section 12 of the Exchange Act or a registration statement pursuant to the requirements of the Securities Act, the

-21-

Company shall, at any time and from time to time, upon the request of any Holder of Registrable Securities and upon the request of any Person designated by such Holder as a prospective purchaser of any Registrable Securities (provided such Person agrees to execute a customary confidentiality agreement relating to the Company’s nonpublic information), furnish in writing to such Holder or such prospective purchaser, as the case may be, a statement as of a date not earlier than 12 months prior to the date of such request of the nature of the business of the Company and the products and services it offers and copies of the Company’s most recent balance sheet and profit and loss and retained earnings statements, together with similar financial statements for the two preceding fiscal years, to the extent that the Company shall have been in operation for such time, all such financial statements to be audited to the extent audited statements are reasonable available, provided that, in any event the most recent financial statements so furnished shall include a balance sheet as of a date less than 16 months prior to the date of such request, statements of profit and loss and retained earnings for the 12 months preceding the date of such balance sheet, and, if such balance sheet is not as of a date less than 6 months prior to the date of such request, additional statements of profit and loss and retained earnings for the period from the date of such balance sheet to a date less than 6 months prior to the date of such request. If the Company shall have filed a registration statement pursuant to the requirements of Section 12 of the Exchange Act or a registration statement pursuant to the requirements of the Securities Act, the Company covenants that it shall timely file any reports required to be filed by it under the Securities Act or the Exchange Act (including, but not limited to, the reports under Sections 13 and 15(d) of the Exchange Act referred to in subparagraph (c) of Rule 144 under the Securities Act), and that it shall take such further action as any Holder of Registrable Securities may reasonably request, all to the extent required from time to time to enable such Holder to sell Registrable Securities without registration under the Securities Act within the limitation of the exemptions provided by (i) Rule 144 and Rule 144A under the Securities Act, as such rules may be amended from time to time, or (ii) any other rule or regulation now existing or hereafter adopted by the SEC. Upon the request of any Holder of Registrable Securities, the Company shall deliver to such Holder a written statement as to whether it has complied with such requirements.

6.4. Amendments and Waivers. The provisions of this Agreement, including the provisions of this sentence, may not be amended, modified, supplemented or terminated, and waivers or consents to departures from the provisions hereof may not be given, without the written consent of the Company and the Majority Holders; provided, however, that no such amendment, modification, supplement, waiver or consent to departure shall reduce the aforesaid percentage of Registrable Securities without the written consent of all of the Holders of Registrable Securities; and provided further, that nothing herein shall prohibit any amendment, modification, supplement, termination, waiver or consent to departure the effect of which is limited only to those Holders who have agreed to such amendment, modification, supplement, termination, waiver or consent to departure.

-22-

6.5. Notices. All notices and other communications provided for or permitted hereunder shall be made in writing by hand delivery, telecopier, any courier guaranteeing overnight delivery or first class registered or certified mail, return receipt requested, postage prepaid, addressed to the applicable party at the address set forth below or such other address as may hereafter be designated in writing by such party to the other parties in accordance with the provisions of this Section:

If to the Company:

ATP Oil & Gas Corporation

4600 Post Oak Place

Suite 200

Houston, Texas 77027

Attention: Chief Financial Officer

Telephone: 713-622-3311

Telecopier: 713-622-5101

with a copy to:

ATP Oil & Gas Corporation

4600 Post Oak Place

Suite 200

Houston, Texas 77027

Attention: General Counsel

Telephone: 713-622-3311

Telecopier: 713-622-0289

if to the Initial Holders, to them at the following addresses:

Wells Fargo Foothill, Inc.

400 North Park Town Center

1000 Abernathy Road

Suite 1450

Atlanta, Georgia 30328

Attention: Business Finance Division Manager

Telephone: 770-508-1300

Telecopier: 770-508-1375

Wells Fargo Foothill, Inc.

2450 Colorado Avenue

Suite 3000

Santa Monica, California 90404

Attention: Structured Finance Division Manager

Telephone: 310-453-7300

Telecopier: 310-453-7442

with a copy to:

Paul, Hastings, Janofsky & Walker LLP

515 South Flower Street, 25^th Floor

Los Angeles, California 90071

Attention: John Francis Hilson, Esq.

Telephone: 213-683-6300

Telecopier: 213-996-3300

-23-

and to,

Ableco Finance LLC

299 Park Avenue, 23^th Floor

New York, New York 10171

Telephone: 212-891-2100

Telecopier: 212-891-1541

in each case, with a copy to:

Schulte Roth & Zabel LLP

919 Third Avenue

New York, New York 10022

Attention: Paul E. Weber, Esq.

Telephone: 212-756-2000

Telecopier: 212-593-5955

If to any subsequent Holder(s), to the address of such Person(s) set forth in the records of the Company.

All such notices and communications shall be deemed to have been duly given: at the time delivered by hand, if personally delivered; when receipt is acknowledged, if telecopied; on the next business day, if timely delivered to a courier guaranteeing overnight delivery; and five days after being deposited in the mail, if sent first class or certified mail, return receipt requested, postage prepaid.

6.6. Successors and Assigns. This Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective heirs, successors and permitted assigns (including any permitted transferee of Warrants or Registrable Securities). At any time after May 17, 2004, any Holder may assign to any permitted (as determined under the Warrant) transferee of its Warrants or Registrable Securities (other than a transferee that acquires such Registrable Securities in a registered public offering or pursuant to a sale under Rule 144 of the Securities Act (or any successor rule)), its rights and obligations under this Agreement; provided, however, (x) that such transferee then holds Warrants or Registrable Securities representing at least 20% of the aggregate number of Warrant Shares issuable or issued pursuant to the Warrant and (y) such transferee shall promptly notify the Company and by taking and holding such Registrable Securities such permitted transferee shall automatically be entitled to receive the benefits of and be conclusively deemed to have agreed to be bound by and to perform all of the terms and provisions of this Agreement as if it were a party hereto (and shall, for all purposes, be deemed a Holder under this Agreement). If the Company shall so request any heir, successor or permitted assign (including any permitted transferee) wishing to avail itself of the benefits of this Agreement shall agree in writing to acquire and hold the Registrable Securities subject to all of the terms hereof. For purposes of this Agreement, “successor” for any entity other than a natural person shall mean a successor to such entity as a result of such entity’s merger, consolidation,

-24-

sale of substantially all of its assets, or similar transaction. Except as provided above or otherwise permitted by this Agreement, neither this Agreement nor any right, remedy, obligation or liability arising hereunder or by reason hereof shall be assignable by any Holder or by the Company without the prior written consent of the other parties hereto. Notwithstanding anything contained in this Section 6.6, this Agreement shall at all times be freely assignable by any Holder to any Related Fund (as defined in the Financing Agreement) or any other affiliate of any Holder.

6.7. Counterparts. This Agreement may be executed in two or more counterparts, each of which, when so executed and delivered, shall be deemed to be an original, but all of which counterparts, taken together, shall constitute one and the same instrument.

6.8. Descriptive Headings, Etc. The headings in this Agreement are for convenience of reference only and shall not limit or otherwise affect the meaning of terms contained herein. Unless the context of this Agreement otherwise requires: (1) words of any gender shall be deemed to include each other gender; (2) words using the singular or plural number shall also include the plural or singular number, respectively; (3) the words “hereof”, “herein” and “hereunder” and words of similar import when used in this Agreement shall refer to this Agreement as a whole and not to any particular provision of this Agreement, and Section and paragraph references are to the Sections and paragraphs of this Agreement unless otherwise specified; (4) the word “including” and words of similar import when used in this Agreement shall mean “including, without limitation,” unless otherwise specified; (5) “or” is not exclusive; and (6) provisions apply to successive events and transactions.

6.9. Severability. In the event that any one or more of the provisions, paragraphs, words, clauses, phrases or sentences contained herein, or the application thereof in any circumstances, is held invalid, illegal or unenforceable in any respect for any reason, the validity, legality and enforceability of any such provision, paragraph, word, clause, phrase or sentence in every other respect and of the other remaining provisions, paragraphs, words, clauses, phrases or sentences hereof shall not be in any way impaired, it being intended that all rights, powers and privileges of the parties hereto shall be enforceable to the fullest extent permitted by law.

6.10. CHOICE OF LAW AND VENUE; JURY TRIAL WAIVER. THE VALIDITY OF THIS AGREEMENT, THE CONSTRUCTION, INTERPRETATION, AND ENFORCEMENT HEREOF, AND THE RIGHTS OF THE PARTIES HERETO WITH RESPECT TO ALL MATTERS ARISING HEREUNDER OR RELATED HERETO SHALL BE DETERMINED UNDER, GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

THE PARTIES AGREE THAT ALL ACTIONS OR PROCEEDINGS ARISING IN CONNECTION WITH THIS AGREEMENT SHALL BE TRIED AND LITIGATED ONLY IN THE STATE AND FEDERAL COURTS LOCATED IN THE COUNTY OF NEW YORK, STATE OF NEW YORK. THE COMPANY AND THE INITIAL HOLDER WAIVE, TO THE EXTENT PERMITTED UNDER APPLICABLE LAW, ANY RIGHT EACH MAY HAVE TO ASSERT THE DOCTRINE OF FORUM

-25-

NON CONVENIENS OR TO OBJECT TO VENUE TO THE EXTENT ANY PROCEEDING IS BROUGHT IN ACCORDANCE WITH THIS SECTION 6.10.

THE COMPANY AND THE INITIAL HOLDER HEREBY WAIVE THEIR RESPECTIVE RIGHTS TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION BASED UPON OR ARISING OUT OF THIS AGREEMENT OR ANY OF THE TRANSACTIONS CONTEMPLATED HEREIN, INCLUDING CONTRACT CLAIMS, TORT CLAIMS, BREACH OF DUTY CLAIMS, AND ALL OTHER COMMON LAW OR STATUTORY CLAIMS. THE COMPANY AND THE INITIAL HOLDER REPRESENT THAT EACH HAS REVIEWED THIS WAIVER AND EACH KNOWINGLY AND VOLUNTARILY WAIVES ITS JURY TRIAL RIGHTS FOLLOWING CONSULTATION WITH LEGAL COUNSEL. IN THE EVENT OF LITIGATION, A COPY OF THIS AGREEMENT MAY BE FILED AS A WRITTEN CONSENT TO A TRIAL BY THE COURT.

6.11. Remedies; Specific Performance. The parties hereto acknowledge that money damages would not be an adequate remedy at law if any party fails to perform in any material respect any of its obligations hereunder, and accordingly agree that each party, in addition to any other remedy to which it may be entitled at law or in equity, shall be entitled to seek to compel specific performance of the obligations of any other party under this Agreement, without the posting of any bond, in accordance with the terms and conditions of this Agreement in any court specified in Section 6.10 hereof, and if any action should be brought in equity to enforce any of the provisions of this Agreement, none of the parties hereto shall raise the defense that there is an adequate remedy at law. Except as otherwise provided by law, a delay or omission by a party hereto in exercising any right or remedy accruing upon any such breach shall not impair the right or remedy or constitute a waiver of or acquiescence in any such breach. No remedy shall be exclusive of any other remedy. All available remedies shall be cumulative.

6.12. Entire Agreement. This Agreement, the Financing Agreement, the Warrants and the other Transaction Documents (collectively, (the “Other Agreements”)) are intended by the parties as a final expression of their agreement and intended to be a complete and exclusive statement of the agreement and understanding of the parties hereto in respect of the subject matter contained herein. There are no restrictions, promises, representations, warranties, covenants or undertakings relating to such subject matter, other than those set forth or referred to herein or in the Other Agreements. This Agreement and the Other Agreements supersede all prior agreements and understandings between the Company and the other parties to this Agreement with respect to such subject matter.

6.13. Further Assurances . Each party hereto shall do and perform or cause to be done and performed all such further acts and things and shall execute and deliver all such other agreements, certificates, instruments and documents as any other party hereto reasonably may request in order to carry out the intent and accomplish the purposes of this Agreement and the consummation of the transactions contemplated hereby.

6.14. Construction. The Company and the Initial Holder acknowledge that each of them has had the benefit of legal counsel of its own choice and has been afforded an

-26-

opportunity to review this Agreement with its legal counsel and that this Agreement shall be construed as if jointly drafted by the Company and the Holders.

6.15. No Inconsistent Agreement. Subject to Sections 2.6 and 6.2, the Company will not hereafter enter into any agreement that restricts, limits or prohibits the exercise of the rights granted to the Holders in this Agreement or the Company’s ability to perform its obligations hereunder.

6.16. Costs and Attorneys’ Fees. In the event that any action, suit or other proceeding is instituted concerning or arising out of this Agreement, the Company and the Initial Holder agree that the prevailing party shall recover from the non-prevailing party all of such prevailing party’s costs and reasonable attorneys’ fees incurred in each and every such action, suit or other proceeding, including any and all appeals or petitions therefrom.

-27-

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly executed as of the date first written above.

COMPANY:
ATP OIL & GAS CORPORATION
By:	/s/ T. Paul Bulmahn
Name:
Title:	President

[Signature Page to Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly executed as of the date first written above.

INITIAL HOLDER:
WELLS FARGO FOOTHILL, INC.
By:	/s/ Drew Stawin
Name:
Title:	Senior Vice President

[Signature Page to Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly executed as of the date first written above.

INITIAL HOLDER:
ABLECO HOLDING LLC
By:	/s/ Stephen Feinberg
Name:
Title:	Chief Executive Officer

[Signature Page to Registration Rights Agreement]

EX-4.2

Exhibit 4.2

WARRANT

THIS WARRANT AND ANY SECURITIES ACQUIRED UPON EXERCISE OF THIS WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS OF ANY STATE AND MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND APPLICABLE STATE SECURITIES LAWS OR PURSUANT TO AN APPLICABLE EXEMPTION TO THE REGISTRATION REQUIREMENTS OF SUCH ACT AND SUCH LAWS. THIS WARRANT AND SUCH SECURITIES MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT IN COMPLIANCE WITH THE CONDITIONS SPECIFIED IN THIS WARRANT.

THIS WARRANT AND THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO THE TERMS AND CONDITIONS OF A REGISTRATION RIGHTS AGREEMENT DATED AS OF FEBRUARY 16, 2004.

THIS WARRANT AND THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO THE TERMS AND CONDITIONS OF A FINANCING AGREEMENT DATED AS OF AUGUST, 13, 2003, AS AMENDED. IN NO EVENT SHALL THIS WARRANT BE EXERCISABLE ON OR PRIOR TO MAY 17, 2004.

ATP OIL & GAS CORPORATION

COMMON STOCK PURCHASE WARRANT

No. W-2 February 16, 2004

Warrant to Purchase

637,500 Shares of Common Stock

ATP OIL & GAS CORPORATION, a Texas corporation (the “Company”), for value received, hereby certifies that ABLECO HOLDING LLC or its registered assigns (the “Holder”), is entitled to purchase from the Company duly authorized, validly issued, fully paid and nonassessable shares of Common Stock, par value $.001 per share, of the Company (the “Common Stock”), at a purchase price per share equal to the Exercise Price, at any time or from time to time on or after May 17, 2004, but prior to 5:00 P.M., New York City time, on February 16, 2009 (the “Expiration Date”), all subject to the terms, conditions and adjustments set forth below in this Warrant.

1

This Warrant is one of the Common Stock Purchase Warrants (the “Warrant” and, collectively, the “Warrants,” such terms to include any such warrants issued in substitution therefor) referred to and issued under that certain Second Amended and Restated Financing Agreement, dated as of August 13, 2003, as amended pursuant to the Consent and Amendment No. 1, dated as of November 14, 2003, Amendment No. 2, dated as of December 3, 2003, and as supplemented by the Joinder Agreement, dated as of December 3, 2003, and Amendment No. 3, dated as of February 16, 2004 (as amended, supplemented or otherwise modified from time to time, the “Financing Agreement”), by and among the Company, as the borrower, each subsidiary of the Company listed as a guarantor on the signature pages thereto, each of the lenders from time to time party thereto, Ableco Finance LLC, as collateral agent and administrative agent for the lenders, and Wells Fargo Foothill, Inc., as funding agent for the lenders. The Warrant originally so issued evidences the right to purchase up to 637,500 shares of Common Stock (the “Initial Number of Shares”), subject to certain adjustments as provided herein. Capitalized terms used herein and not otherwise defined herein shall have the meanings assigned such terms in the Financing Agreement.

1. Definitions. As used herein, unless the context otherwise requires, the following terms shall have the meanings indicated:

“Additional Shares of Common Stock” shall mean (without duplication) all shares (including treasury shares) of Common Stock issued or sold (or, pursuant to Section 3.3 or 3.4, deemed to be issued) by the Company after the date hereof, whether or not subsequently reacquired or retired by the Company, other than (a) shares issued upon the exercise of this Warrant or any other Warrant issued in connection with the Financing Agreement and (b) such number of additional shares as may become issuable upon the exercise of the Warrants by reason of adjustments required pursuant to the provisions of such Warrants as in effect on the date hereof.

“Applicable Number of Shares” shall mean at any date of determination a number of shares of Common Stock equal to the difference between (a) the Initial Number of Shares, less (b) the number of shares of Common Stock which were issued pursuant to the exercise of this Warrant, as determined immediately prior to such date (giving effect to any stock splits or combinations, or any dividends paid or payable in shares of Common Stock, after the issuance of such shares).

“Business Day” shall mean any day other than a Saturday or a Sunday or a day on which commercial banking institutions in the City of New York are authorized by law to be closed. Any reference to “days” (unless Business Days are specified) shall mean calendar days.

“Commission” shall mean the Securities and Exchange Commission or any successor agency having jurisdiction to enforce the Securities Act.

“Common Stock” shall have the meaning assigned to it in the introduction to this Warrant, such term to include any stock into which the Common Stock shall have been changed or any stock resulting from any reclassification of such Common Stock, and all other stock of any class or classes (however designated) of the Company the holders of which have the right,

2

without limitation as to amount, either to all or to a share of the balance of current dividends and liquidating dividends after the payment of dividends and distributions on any shares entitled to preference.

“Company” shall have the meaning assigned to it in the introduction to this Warrant, such term to include any corporation or other entity which shall succeed to or assume the obligations of the Company hereunder in compliance with Section 4.

“Convertible Securities” shall mean any evidences of indebtedness, shares of stock (other than Common Stock) or other securities directly or indirectly convertible into or exchangeable for Additional Shares of Common Stock.

“Current Market Price” shall mean, on any date specified herein, the average of the daily Market Price during the 5 consecutive trading days before such date, except that, if on any such date the shares of Common Stock are not listed or admitted for trading on any national securities exchange or quoted in the over-the-counter market, the Current Market Price shall be the Market Price on such date.

“Exchange Act” shall mean the Securities Exchange Act of 1934, as amended from time to time, and the rules and regulations thereunder, or any successor statute.

“Exercise Price” shall mean the Initial Price, as adjusted from time to time as provided herein.

“Expiration Date” shall have the meaning assigned to it in the introduction to this Warrant.

“Fair Value” shall mean, on any date specified herein (i) in the case of cash, the dollar amount thereof, (ii) in the case of a security, the Market Price, and (iii) in all other cases, the fair value thereof (as of a date which is within 20 days of the date as of which the determination is to be made) determined in good faith jointly by the Company and a Majority of the Holders; provided, however, that if such parties are unable to reach agreement within a reasonable period of time, the Fair Value shall be determined in good faith, by an independent investment banking firm selected jointly by the Company and a Majority of the Holders or, if that selection cannot be made within ten days, by an independent investment banking firm selected by the American Arbitration Association in accordance with its rules, and provided further, that the Company shall pay all of the fees and expenses of any third parties incurred in connection with determining the Fair Value.

“Financing Agreement” shall have the meaning assigned to it in the introduction to this Warrant.

“Financing Agreement Date” shall mean February 16, 2004.

“Holder” shall have the meaning assigned to it in the introduction to this Warrant.

3

“Initial Number of Shares” shall have the meaning assigned to it in the introduction to this Warrant.

“Initial Price” means $6.75.

“Majority of the Holders” shall mean the Holders of this Warrant and any other Warrants issued pursuant to the Financing Agreement who shall be entitled, upon exercise of their Warrants, to purchase more than 50% of all shares of Common Stock then issuable under all such Warrants.

“Market Price” shall mean, on any date specified herein, the amount per share of the Common Stock, equal to (a) the last reported sale price of such Common Stock, regular way, on such date or, in case no such sale takes place on such date, the average of the closing bid and asked prices thereof regular way on such date, in either case as officially reported on the principal national securities exchange on which such Common Stock is then listed or admitted for trading, (b) if such Common Stock is not then listed or admitted for trading on any national securities exchange but is designated as a national market system security by the NASD, the last reported trading price of the Common Stock on such date, (c) if there shall have been no trading on such date or if the Common Stock is not so designated, the average of the closing bid and asked prices of the Common Stock on such date as shown by the NASD automated quotation system, or (d) if such Common Stock is not then listed or admitted for trading on any national exchange or quoted in the over-the-counter market, the fair value thereof (as of a date which is within 20 days of the date as of which the determination is to be made) determined in good faith jointly by the Company and a Majority of the Holders; provided, however, that if such parties are unable to reach agreement within a reasonable period of time, the Market Price shall be determined in good faith by an independent investment banking firm selected jointly by the Company and a Majority of the Holders or, if that selection cannot be made within ten days, by an independent investment banking firm selected by the American Arbitration Association in accordance with its rules, and provided further, that the Company shall pay all of the fees and expenses of any third parties incurred in connection with determining the Market Price.

“NASD” shall mean the National Association of Securities Dealers, Inc.

“Notice” shall have the meaning assigned to it in Section 2.1(a) of this Agreement.

“Options” shall mean any rights, options or warrants to subscribe for, purchase or otherwise acquire Additional Shares of Common Stock or Convertible Securities.

“Other Securities” shall mean any stock (other than Common Stock) and other securities of the Company or any other Person (corporate or otherwise) which the holders of the Warrants at any time shall be entitled to receive, or shall have received, upon the exercise of the Warrants, in lieu of or in addition to Common Stock, or which at any time shall be issuable or shall have been issued in exchange for or in replacement of Common Stock or Other Securities pursuant to Section 4 or otherwise.

4

“Permitted Issuances” shall mean any issuance of capital stock of the Company which constitutes a Permitted Preferred Equity Issuance (as such term is defined in Amendment No. 3, dated February 16, 2004, to the Financing Agreement).

“Person” shall mean any individual, firm, partnership, corporation, trust, joint venture, association, joint stock company, limited liability company, unincorporated organization or any other entity or organization, including a government or agency or political subdivision thereof, and shall include any successor (by merger or otherwise) of such entity.

“Purchase Price” shall have the meaning assigned to it in Section 2.1(a) of this Agreement.

“Registration Rights Agreement” means that certain Registration Rights Agreement, dated the date hereof, by and between the Company thereof and each Holder, as may be amended from time to time, including the demand and piggy-back registration rights of the Holders and the other provisions thereof with respect to the Warrants and the shares of Common Stock issuable upon the exercise of the Warrants.

“Restricted Securities” shall mean (a) any Warrants bearing the applicable legend set forth in Section 9.1, (b) any shares of Common Stock (or Other Securities) issued or issuable upon the exercise of Warrants which are (or, upon issuance, will be) evidenced by a certificate or certificates bearing the applicable legend set forth in such Section, and (c) any shares of Common Stock (or Other Securities) issued subsequent to the exercise of any of the Warrants as a dividend or other distribution with respect to, or resulting from a subdivision of the outstanding shares of Common Stock (or other Securities) into a greater number of shares by reclassification, stock splits or otherwise, or in exchange for or in replacement of the Common Stock (or Other Securities) issued upon such exercise, which are evidenced by a certificate or certificates bearing the applicable legend set forth in such Section.

“Securities Act” shall mean the Securities Act of 1933, as amended from time to time, and the rules and regulations thereunder, or any successor statute.

“Warrant or Warrants” shall have the meaning assigned to it in the introduction to this Warrant.

2. Exercise of Warrant.

2.1. Manner of Exercise; Payment of the Purchase Price. (a) This Warrant may be exercised by the Holder hereof, in whole or in part, at any time or from time to time on or after May 17, 2004 but prior to the Expiration Date, for a number of shares of Common Stock not greater than the then-Applicable Number of Shares determined as of the date of exercise, by surrendering to the Company at its principal office this Warrant, with the form of Election to Purchase Shares (the “Notice”) attached hereto as Exhibit A (or a reasonable facsimile thereof) duly executed by the Holder, which Notice shall specify the number of shares of Common Stock to be issued to such Holder and accompanied by payment of the applicable purchase price (the

5

“Purchase Price”) in an amount equal to the product of (i) the Exercise Price and (ii) the number of shares of Common Stock to be issued.

(b) Payment of the Purchase Price may be made as follows (or by any combination of the following): (i) in United States currency by cash or delivery of a certified check or bank draft payable to the order of the Company or by wire transfer to the Company, (ii) by cancellation of all or any part of the unpaid principal amount of the then-outstanding Obligations (as defined in the Financing Agreement) in an amount equal to the Purchase Price, (iii) by cancellation of such number of the shares of Common Stock otherwise issuable to the Holder upon such exercise as shall be specified in such Election to Purchase Shares, such that the excess of the aggregate Current Market Price of such specified number of shares on the date of exercise over the portion of the Purchase Price attributable to such shares shall equal the Purchase Price attributable to the shares of Common Stock to be issued upon such exercise, in which case such amount shall be deemed to have been paid to the Company and the number of shares issuable upon such exercise shall be reduced by such specified number, (iv) by surrender to the Company for cancellation certificates representing shares of Common Stock of the Company owned by the Holder (properly endorsed for transfer in blank) having a Current Market Price on the date of Warrant exercise equal to the Purchase Price, or (v) by a combination of the methods described in clauses (i), (ii), (iii) and (iv).

2.2. When Exercise Effective. Each exercise of this Warrant shall be deemed to have been effected as of the later to occur of (a) receipt of payment of the Purchase Price and (b) immediately prior to the close of business on the Business Day on which this Warrant shall have been surrendered to the Company as provided in Section 2.1, and at such time of effectiveness the Person or Persons in whose name or names any certificate or certificates for shares of Common Stock (or Other Securities) shall be issuable upon such exercise as provided in Section 2.3 shall be deemed to have become the holder or holders of record thereof for all purposes.

2.3. Delivery of Stock Certificates, etc.; Charges, Taxes and Expenses. (a) As soon as practicable after each exercise of this Warrant, in whole or in part, and in any event within five Business Days thereafter, the Company shall cause to be issued in the name of and delivered to the Holder hereof or, subject to Section 10, as the Holder may direct, a certificate or certificates for the number of shares of Common Stock (or Other Securities) to which the Holder shall be entitled upon such exercise plus, in lieu of issuance of any fractional share to which the Holder would otherwise be entitled, if any, a check for the amount of cash equal to the same fraction multiplied by the Exercise Price per share on the date of Warrant exercise.

In case any such exercise is for less than all of the then-Applicable Number of Shares as of the date of exercise purchasable under this Warrant, this Warrant or a new Warrant or Warrants of like tenor, shall be returned to the Holder, noting the number of shares of Common Stock issued hereunder to date.

The Company will pay all documentary stamp taxes attributable to the initial issuance of shares of Common Stock upon the exercise of Warrants; provided, however, that the Company shall not be required to pay any tax or taxes which may be payable in respect of any

6

transfer involved in the issue of any Warrants or any certificates for shares of Common stock in a name other than that of the Holder, and the Company shall not be required to issue or deliver such Warrant or shares of Common Stock unless or until the person or persons requesting the issuance thereof shall have paid to the Company the amount of such tax or shall have established to the satisfaction of the Company that such tax has been paid.

3. Adjustment of Common Stock Issuable Upon Exercise; Adjustment of Exercise Price.

3.1. Adjustment of Number of Shares. From and after the date hereof, upon each adjustment of the Exercise Price as a result of the calculations made in this Section 3, this Warrant shall thereafter evidence the right to receive, at the adjusted Exercise Price, that number of shares of Common Stock (calculated to the nearest one-hundredth) obtained by dividing (i) the product of the aggregate number of shares covered by this Warrant immediately prior to such adjustment and the Exercise Price in effect immediately prior to such adjustment of the Exercise Price by (ii) the Exercise Price in effect immediately after such adjustment of the Exercise Price.

3.2. Adjustment of Exercise Price.

3.2.1. Issuance of Additional Shares of Common Stock. In case the Company at any time or from time to time after the Financing Agreement Date shall issue or sell Additional Shares of Common Stock (including Additional Shares of Common Stock deemed to be issued pursuant to Section 3.3 or 3.4) without consideration or for a consideration per share less than the Market Price in effect immediately prior to such issue or sale, then, and in each such case (other than issuances pursuant to this Section 3.2.1 consented to in advance by a majority of the Holders and Permitted Issuances), subject to Section 3.8, the Exercise Price shall be reduced, concurrently with such issue or sale, to a price (calculated to the nearest .001 of a cent) determined by multiplying such Exercise Price by a fraction

(a) the numerator of which shall be the sum of (i) the number of shares of Common Stock outstanding immediately prior to such issue or sale and (ii) the number of shares of Common Stock which the aggregate consideration received by the Company for the total number of such Additional Shares of Common Stock so issued or sold would purchase at such Market Price, and

(b) the denominator of which shall be the number of shares of Common Stock outstanding immediately after such issue or sale, provided, however, that, for the purposes of this Section 3.2.1, (x) immediately after any Additional Shares of Common Stock are deemed to have been issued pursuant to Section 3.3 or 3.4, such Additional Shares shall be deemed to be outstanding, and (y) treasury shares shall not be deemed to be outstanding.

3.2.2. Extraordinary Dividends and Distributions. In case the Company at any time or from time to time after the Financing Agreement Date shall declare, order, pay or make a dividend (excluding dividends consented to in advance by the majority of the Holders) or other distribution (including, without limitation, any distribution of other or additional stock or other

7

securities or property or Options by way of dividend or spin-off, reclassification, recapitalization or similar corporate rearrangement) on the Common Stock, subject to Section 3.8, the Exercise Price in effect immediately prior to the close of business on the record date fixed for the determination of holders of any class of securities entitled to receive such dividend or distribution shall be reduced, effective as of the close of business on such record date, to a price determined by multiplying such Exercise Price by a fraction

(x) the numerator of which shall be the Market Price in effect on such record date or, if the Common Stock trades on an ex-dividend basis, on the date prior to the commencement of ex-dividend trading, less the Fair Value of such dividend or distribution applicable to one share of Common Stock, and

(y) the denominator of which shall be such Market Price.

3.3. Treatment of Options and Convertible Securities. In case the Company at any time or from time to time after the Financing Agreement Date shall issue, sell, grant or assume, or shall fix a record date for the determination of holders of any class of securities of the Company entitled to receive, any Options or Convertible Securities (whether or not the rights thereunder are immediately exercisable), then, and in each such case, the maximum number of Additional Shares of Common Stock (as set forth in the instrument relating thereto, without regard to any provisions contained therein for a subsequent adjustment of such number) issuable upon the exercise of such Options or, in the case of Convertible Securities and Options therefor, or the conversion or exchange of such Convertible Securities, shall be deemed to be Additional Shares of Common Stock issued as of the time of such issue, sale, grant or assumption or, in case such a record date shall have been fixed, as of the close of business on such record date (or, if the Common Stock trades on an ex-dividend basis, on the date prior to the commencement of ex-dividend trading), provided, however, that such Additional Shares of Common Stock shall not be deemed to have been issued unless the consideration per share (determined pursuant to Section 3.5) of such shares would be less than the Market Price in effect on the date of and immediately prior to such issue, sale, grant or assumption or immediately prior to the close of business on such record date (or, if the Common Stock trades on an ex-dividend basis, on the date prior to the commencement of ex-dividend trading), as the case may be and provided, further, that in any such case in which Additional Shares of Common Stock are deemed to be issued:

(a) whether or not the Additional Shares of Common Stock underlying such Options or Convertible Securities are deemed to be issued, no further adjustment of the Exercise Price shall be made upon the subsequent issue or sale of Convertible Securities or shares of Common Stock upon the exercise of such Options or the conversion or exchange of such Convertible Securities, except in the case of any such Options or Convertible Securities which contain provisions requiring an adjustment, subsequent to the date of the issue or sale thereof, of the number of Additional Shares of Common Stock issuable upon the exercise of such Options or the conversion or exchange of such Convertible Securities by reason of (x) a change of control of the Company, (y) the acquisition by any Person or group of Persons of any specified number or percentage of the voting securities of the Company or (z) any similar event or occurrence, each such

8

case to be deemed hereunder to involve a separate issuance of Additional Shares of Common Stock, Options or Convertible Securities, as the case may be;

(b) if such Options or Convertible Securities by their terms provide, with the passage of time or otherwise, for any increase in the consideration payable to the Company, or decrease in the number of Additional Shares of Common Stock issuable, upon the exercise, conversion or exchange thereof (by change of rate or otherwise), the Exercise Price computed upon the original issue, sale, grant or assumption thereof (or upon the occurrence of the record date, or date prior to the commencement of ex-dividend trading, as the case may be, with respect thereto), and any subsequent adjustments based thereon, shall, upon any such increase or decrease becoming effective, be recomputed to reflect such increase or decrease insofar as it affects such Options, or the rights of conversion or exchange under such Convertible Securities, which are outstanding at such time;

(c) upon the expiration (or purchase by the Company and cancellation or retirement) of any such Options which shall not have been exercised or the expiration of any rights of conversion or exchange under any such Convertible Securities which (or purchase by the Company and cancellation or retirement of any such Convertible Securities the rights of conversion or exchange under which) shall not have been exercised, the Exercise Price computed upon the original issue, sale, grant or assumption thereof (or upon the occurrence of the record date, or date prior to the commencement of ex-dividend trading, as the case may be, with respect thereto), and any subsequent adjustments based thereon, shall, upon such expiration (or such cancellation or retirement, as the case may be), be recomputed as if:

(i) in the case of Options for Common Stock or Convertible Securities, the only Additional Shares of Common Stock issued or sold were the Additional Shares of Common Stock, if any, actually issued or sold upon the exercise of such Options or the conversion or exchange of such Convertible Securities and the consideration received therefor was the consideration actually received by the Company for the issue, sale, grant or assumption of all such Options, whether or not exercised, plus the consideration actually received by the Company upon such exercise, or for the issue or sale of all such Convertible Securities which were actually converted or exchanged, plus the additional consideration, if any, actually received by the Company upon such conversion or exchange, and

(ii) in the case of Options for Convertible Securities, only the Convertible Securities, if any, actually issued or sold upon the exercise of such Options were issued at the time of the issue or sale, grant or assumption of such Options, and the consideration received by the Company for the Additional Shares of Common Stock deemed to have then been issued was the consideration actually received by the Company for the issue, sale, grant or assumption of all such Options, whether or not exercised, plus the consideration deemed to have been received by the Company (pursuant to Section 3.5) upon the issue or sale of such

9

Convertible Securities with respect to which such Options were actually exercised;

(d) no readjustment pursuant to subdivision (b) or (c) above shall have the effect of increasing the Exercise Price by an amount in excess of the amount of the adjustment thereof originally made in respect of the issue, sale, grant or assumption of such Options or Convertible Securities; and

(e) in the case of any such Options which expire by their terms not more than 30 days after the date of issue, sale, grant or assumption thereof, no adjustment of the Exercise Price shall be made until the expiration or exercise of all such Options, whereupon such adjustment shall be made in the manner provided in subdivision (c) above.

3.4. Treatment of Stock Dividends, Stock Splits, etc. In case the Company at any time or from time to time after the Financing Agreement Date shall declare or pay any dividend on the Common Stock payable in Common Stock, or shall effect a subdivision of the outstanding shares of Common Stock into a greater number of shares of Common Stock (by reclassification or otherwise than by payment of a dividend in Common Stock), then, and in each such case, Additional Shares of Common Stock shall be deemed to have been issued (a) in the case of any such dividend, immediately after the close of business on the record date for the determination of holders of any class of securities entitled to receive such dividend, or (b) in the case of any such subdivision, at the close of business on the day immediately prior to the day upon which such corporate action becomes effective.

3.5. Computation of Consideration. For the purposes of this Section 3,

(a) the consideration for the issue or sale of any Additional Shares of Common Stock shall, irrespective of the accounting treatment of such consideration,

(i) insofar as it consists of cash, be computed at the net amount of cash received by the Company, without deducting any expenses paid or incurred by the Company or any commissions or compensations paid or concessions or discounts allowed to underwriters, dealers or others performing similar services in connection with such issue or sale,

(ii) insofar as it consists of property (including securities) other than cash, be computed at the Fair Value thereof at the time of such issue or sale, and

(iii) in case Additional Shares of Common Stock are issued or sold together with other stock or securities or other assets of the Company for a consideration which covers both, be the portion of such consideration so received, computed as provided in clauses (i) and (ii) above, allocable to such Additional Shares of Common Stock, such allocation to be determined in the same manner that the Fair Value of property not consisting of cash or securities is to be determined as provided in the definition of “Fair Value” herein;

10

(b) Additional Shares of Common Stock deemed to have been issued pursuant to Section 3.3, relating to Options and Convertible Securities, shall be deemed to have been issued for a consideration per share determined by dividing

(i) the total amount, if any, received and receivable by the Company as consideration for the issue, sale, grant or assumption of the Options or Convertible Securities in question, plus the minimum aggregate amount of additional consideration (as set forth in the instruments relating thereto, without regard to any provision contained therein for a subsequent adjustment of such consideration to protect against dilution) payable to the Company upon the exercise in full of such Options or the conversion or exchange of such Convertible Securities or, in the case of Options for Convertible Securities, the exercise of such Options for Convertible Securities and the conversion or exchange of such Convertible Securities, in each case computing such consideration as provided in the foregoing subdivision (a),

by

(ii) the maximum number of shares of Common Stock (as set forth in the instruments relating thereto, without regard to any provision contained therein for a subsequent adjustment of such number to protect against dilution) issuable upon the exercise of such Options or the conversion or exchange of such Convertible Securities; and

(c) Additional Shares of Common Stock deemed to have been issued pursuant to Section 3.4, relating to stock dividends, stock splits and similar corporate events shall be deemed to have been issued for no consideration.

3.6. Adjustments for Combinations, etc. If after the Financing Agreement Date the outstanding shares of Common Stock shall be combined or consolidated, by reclassification or otherwise, into a lesser number of shares of Common Stock, the Exercise Price in effect immediately prior to such combination or consolidation shall, concurrently with the effectiveness of such combination or consolidation, be proportionately increased.

3.7. Dilution in Case of Other Securities. If after the Financing Agreement Date any Other Securities shall be issued or sold or shall become subject to issue or sale upon the conversion or exchange of any stock (or Other Securities) of the Company (or any issuer of Other Securities or any other Person referred to in Section 4) or to subscription, purchase or other acquisition pursuant to any Options issued or granted by the Company (or any such other issuer or Person) for a consideration such as to dilute, on a basis consistent with the standards established in the other provisions of this Section 3, the purchase rights granted by this Warrant, then, and in each such case, the computations, adjustments and readjustments provided for in this Section 3 with respect to the Exercise Price shall be made as nearly as possible in the manner so provided and applied to determine the amount of Other Securities from time to time receivable upon the exercise of the Warrants, so as to protect the holders of the Warrants against the effect of such dilution.

11

3.8. De Minimis Adjustments; Certain Retroactive Adjustments. If the amount of any adjustment of the Exercise Price per share required pursuant to this Section 3 would be less than one tenth (1/10) of one percent (1%) of the Exercise Price, such amount shall be carried forward and adjustment with respect thereto made at the time of and together with any subsequent adjustment which, together with such amount and any other amount or amounts so carried forward, shall aggregate a change in the Exercise Price of at least one tenth (1/10) of one percent (1%) of such Exercise Price. All calculations under this Warrant shall be made to the nearest .001 of a cent or to the nearest one-hundredth of a share, as the case may be.

3.9. Abandoned Dividend or Distribution. If after the Financing Agreement Date the Company shall take a record of the holders of its Common Stock for the purpose of entitling them to receive a dividend or other distribution (which results in an adjustment to the Exercise Price under the terms of this Warrant) and shall, thereafter, and before such dividend or distribution is paid or delivered to shareholders entitled thereto, legally abandon its plan to pay or deliver such dividend or distribution, then any adjustment made to the Exercise Price by reason of the taking of such record shall be reversed, and any subsequent adjustments, based thereon, shall be recomputed.

4. Consolidation, Merger, Etc.

4.1. Adjustments for Consolidation, Merger, Sale of Assets, Reorganization, etc. In case the Company (a) shall consolidate with or merge into any other Person and shall not be the continuing or surviving corporation of such consolidation or merger, or (b) shall permit any other Person to consolidate with or merge into the Company and the Company shall be the continuing or surviving Person but, in connection with such consolidation or merger, the Common Stock or Other Securities shall be changed into or exchanged for stock or other securities of any other Person or cash or any other property, or (c) shall transfer all or substantially all of its properties or assets to any other Person and shall thereafter distribute any material portion of the proceeds of such transaction to its shareholders generally, or (d) shall effect a capital reorganization or reclassification of the Common Stock or Other Securities (other than a capital reorganization or reclassification of the Common Stock resulting in the issuance of Additional Shares of Common Stock for which adjustment in the Purchase Price is provided in Section 3.2.1 or 3.2.2), then, and in the case of each such transaction, proper provision shall be made so that, upon the basis and the terms and in the manner provided in this Warrant, the Holder of this Warrant, upon the exercise hereof at any time after the consummation of such transaction, shall be entitled to receive (at the aggregate Purchase Price in effect immediately prior to the time of such consummation for all Common Stock or Other Securities issuable upon such exercise immediately prior to such consummation), in lieu of the Common Stock or Other Securities issuable upon such exercise prior to such consummation, the highest amount of securities, cash or other property to which such Holder would actually have been entitled as a shareholder upon such consummation if such Holder had exercised this Warrant for all of the then-Applicable Number of Shares immediately prior thereto, subject to adjustments (subsequent to such consummation) as nearly equivalent as possible to the adjustments provided for in Sections 3 through 5.

12

4.2. Assumption of Obligations. Notwithstanding anything contained in the Warrants or in the Financing Agreement to the contrary, the Company shall not effect any of the transactions described in clauses (a) through (d) of Section 4.1 unless, prior to the consummation thereof, each Person (other than the Company) which may be required to deliver any stock, securities, cash or property upon the exercise of this Warrant as provided herein shall assume, by written instrument delivered to the Holder of this Warrant, (a) the obligations of the Company under this Warrant (and if the Company shall survive the consummation of such transaction, such assumption shall be in addition to, and shall not release the Company from, any continuing obligations of the Company under this Warrant), (b) the obligations of the Company under the Registration Rights Agreement and (c) the obligation to deliver to the Holder such shares of stock, securities, cash or property as, in accordance with the foregoing provisions of this Section 4, the Holder may be entitled to receive and such Person shall have similarly delivered to the Holder an opinion of counsel for such person, which counsel shall be reasonably satisfactory to the Holder, stating that this Warrant shall thereafter continue in full force and effect and the terms hereof (including, without limitation, all of the provisions of this Section 4) shall be applicable to the stock, securities, cash or property which such person may be required to deliver upon any exercise of this Warrant or the exercise of any rights pursuant thereto. Nothing in this Section 4 shall be deemed to authorize the Company to enter into any transaction not otherwise permitted by the Financing Agreement.

5. Other Dilutive Events. In case any event shall occur as to which the provisions of Section 3 or Section 4 are not strictly applicable or if strictly applicable would not, in the reasonable judgment of the Board of Directors, fairly protect the purchase rights represented by this Warrant in accordance with the essential intent and principles of such Sections, then, in each such case, the Board of Directors of the Company shall, in good faith, make an adjustment in the application of such provisions, in accordance with the essential intent and principles hereof, so as to preserve, without dilution, the purchase rights represented by this Warrant.

6. No Dilution or Impairment. The Company shall not, by amendment of its Articles of Incorporation or through any consolidation, merger, reorganization, transfer of assets, dissolution, issue or sale of securities or any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms of this Warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all such action as may be necessary or appropriate in order to protect the rights of the Holder of this Warrant against dilution or other impairment in accordance with the terms hereof. Without limiting the generality of the foregoing, the Company (a) shall not permit the par value of any shares of stock receivable upon the exercise of this Warrant to exceed the amount payable therefor upon such exercise, (b) shall take all such action as may be necessary or appropriate in order that the Company may validly and legally issue fully paid and nonassessable shares of stock, free from all taxes, liens, security interests, encumbrances, preemptive rights and charges on the exercise of the Warrants from time to time outstanding, and (c) shall not amend or modify any provision of the Articles of Incorporation or by-laws of the Company in any manner that would adversely affect in any way the rights or powers of the Holder of this Warrant in its capacity as such.

13

7. Notices of Corporate Action. In the event of:

(a) any taking by the Company of a record of the holders of any class of securities for the purpose of determining the holders thereof who are entitled to receive any dividend or other distribution, or any right to subscribe for, purchase or otherwise acquire any shares of stock of any class or any other securities or property, or to receive any other right, or

(b) any capital reorganization of the Company, any reclassification or recapitalization of the capital stock of the Company, any consolidation or merger involving the Company and any other Person, any transaction or series of transactions in which more than 50% of the voting securities of the Company are transferred to another Person, or any transfer, sale or other disposition of all or substantially all the assets of the Company to any other Person, or

(c) any voluntary or involuntary dissolution, liquidation or winding-up of the Company,

the Company shall mail to each holder of a Warrant a notice specifying (i) the date or expected date on which any such record is to be taken for the purpose of such dividend, distribution or right, and the amount and character of such dividend, distribution or right, and (ii) the date or expected date on which any such reorganization, reclassification, recapitalization, consolidation, merger, transfer, sale, disposition, dissolution, liquidation or winding-up is to take place and the time, if any such time is to be fixed, as of which the holders of record of Common Stock (or Other Securities) shall be entitled to exchange their shares of Common Stock (or Other Securities) for the securities or other property deliverable upon such reorganization, reclassification, recapitalization, consolidation, merger, transfer, dissolution, liquidation or winding-up. In the case of any action covered by clause (a) above, such notice shall be mailed by the Company at least 10 days prior to the date on which such record is to be taken, and, in the case of any action covered by clause (b) or (c) above, such notice shall be mailed by the Company at least 20 days prior to the date or expected date on which such action is to take place.

8. Listing of Common Stock. At any such time as Common Stock is listed on any national securities exchange, the Company shall, at its expense, obtain promptly and maintain the approval for listing on the principal such exchange, upon official notice of issuance, the shares of Common Stock issuable upon exercise of the then outstanding Warrants and maintain the listing of such shares after their issuance; and the Company shall also list on such national securities exchange and shall maintain such listing of, any Other Securities that at any time are issuable upon exercise of the Warrants, if and at the time that any securities of the same class shall be listed on such national securities exchange by the Company.

14

9. Restrictions on Transfer.

9.1. Restrictive Legends. Except as otherwise permitted by this Section 9, each Warrant (including each Warrant issued upon the transfer of any Warrant) shall be stamped or otherwise imprinted with a legend in substantially the following form:

“THIS WARRANT AND ANY SECURITIES ACQUIRED UPON THE EXERCISE OF THIS WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS OF ANY STATE, AND MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND APPLICABLE STATE SECURITIES LAWS OR PURSUANT TO AN APPLICABLE EXEMPTION TO THE REGISTRATION REQUIREMENTS OF SUCH ACT AND SUCH LAWS. THIS WARRANT AND SUCH SECURITIES MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT IN COMPLIANCE WITH THE CONDITIONS SPECIFIED IN THIS WARRANT.”

“THIS WARRANT AND THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO THE TERMS AND CONDITIONS OF A REGISTRATION RIGHTS AGREEMENT DATED AS OF FEBRUARY 16, 2004, AS SUCH AGREEMENT MAY BE AMENDED, MODIFIED, SUPPLEMENTED, RESTATED OR OTHERWISE CHANGED FROM TIME TO TIME.”

Except as otherwise permitted by this Section 9, during the term of the Financing Agreement, each Warrant (including each Warrant issued upon the transfer of any Warrant) shall be stamped or otherwise imprinted with a legend in substantially the following form:

“THIS WARRANT AND THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO THE TERMS AND CONDITIONS OF A FINANCING AGREEMENT DATED AS OF AUGUST 13, 2003, AS SUCH AGREEMENT MAY BE AMENDED, MODIFIED, SUPPLEMENTED, RESTATED OR OTHERWISE CHANGED FROM TIME TO TIME.”

Except as otherwise permitted by this Section 9, each certificate for Common Stock (or Other Securities) issued upon the exercise of any Warrant, and each certificate issued upon the transfer of any such Common Stock (or Other Securities), shall be stamped or otherwise imprinted with a legend in substantially the following form:

“THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS OF ANY STATE, AND MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND APPLICABLE STATE SECURITIES LAWS OR PURSUANT TO AN APPLICABLE EXEMPTION TO THE REGISTRATION REQUIREMENTS OF SUCH ACT AND SUCH LAWS. SUCH SECURITIES MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT IN COMPLIANCE WITH THE CONDITIONS SPECIFIED IN COMMON STOCK PURCHASE WARRANT ISSUED BY ATP OIL & GAS CORPORATION. A COMPLETE AND CORRECT COPY OF THE FORM OF SUCH WARRANT IS AVAILABLE FOR INSPECTION AT THE PRINCIPAL

15

OFFICE OF ATP OIL & GAS CORPORATION. OR AT THE OFFICE OR AGENCY MAINTAINED BY ATP OIL & GAS CORPORATION AS PROVIDED IN SUCH WARRANT AND WILL BE FURNISHED TO THE HOLDER OF SUCH SECURITIES UPON WRITTEN REQUEST AND WITHOUT CHARGE.”

“THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO THE TERMS AND CONDITIONS OF A REGISTRATION RIGHTS AGREEMENT, DATED AS OF FEBRUARY 16, 2004, AS SUCH AGREEMENT MAY BE AMENDED, MODIFIED, SUPPLEMENTED, RESTATED OR OTHERWISE CHANGED FROM TIME TO TIME.”

9.2. Transfer to Comply With the Securities Act. Restricted Securities may not be sold, assigned, pledged, hypothecated, encumbered or in any manner transferred or disposed of, in whole or in part, except in compliance with the provisions of the Securities Act and state securities or Blue Sky laws and the terms and conditions hereof. Other than in connection with any sale, assignment, pledge, hypothecation, encumbrance or any transfer or disposition of this Warrant (or any part thereof) by the Holder to any Related Fund (as defined in the Financing Agreement) or any other affiliate of the Holder, prior to effecting any such sale, assignment, pledge, hypothecation, encumbrance, transfer or disposition, the Holder shall deliver to the Company an opinion of counsel, reasonably satisfactory to the Company, to the effect that such transfer does not require registration under the Securities Act and is otherwise in compliance with the Securities Act and any applicable state securities or Blue Sky laws.

9.3. Termination of Restrictions. The restrictions imposed by this Section 9 on the transferability of Restricted Securities shall cease and terminate as to any particular Restricted Securities (a) when a registration statement with respect to the sale of such securities shall have been declared effective under the Securities Act and such securities shall have been disposed of in accordance with such registration statement, (b) when such securities are sold pursuant to Rule 144 (or any similar provision then in force) under the Securities Act, or (c) when, in the opinion of both counsel for the Holder and counsel for the Company, such restrictions are no longer required or necessary in order to protect the Company against a violation of the Securities Act upon any sale or other disposition of such securities without registration thereunder. Whenever such restrictions shall cease and terminate as to any Restricted Securities, the Holder shall be entitled to receive from the Company, without expense (other than applicable transfer taxes, if any), new securities of like tenor not bearing the applicable legends required by Section 9.1.

10. Reservation of Stock, Etc. The Company shall at all times reserve and keep available, solely for issuance and delivery upon exercise of this Warrant, the number of shares of Common Stock (or Other Securities) from time to time issuable upon exercise of this Warrant. All shares of Common Stock (or Other Securities) issuable upon exercise of this Warrant shall be duly authorized and, when issued upon such exercise, shall be validly issued and, in the case of shares, fully paid and nonassessable with no liability on the part of the holders thereof, and, in the case of all securities, shall be free from all taxes, liens, security interests, encumbrances, preemptive rights and charges. The transfer agent for the Common Stock, which may be the Company (“Transfer Agent”), and every subsequent Transfer Agent for any shares of

16

the Company’s capital stock issuable upon the exercise of any of the purchase rights represented by this Warrant, are hereby irrevocably authorized and directed at all times until the Expiration Date to reserve such number of authorized and unissued shares as shall be requisite for such purpose. The Company shall keep copies of this Warrant on file with the Transfer Agent for the Common Stock and with every subsequent Transfer Agent for any shares of the Company’s capital stock issuable upon the exercise of the rights of purchase represented by this Warrant. The Company shall supply such Transfer Agent with duly executed stock certificates for such purpose. All Warrant Certificates surrendered upon the exercise of the rights thereby evidenced and not required to be returned to the Holder pursuant hereto shall be canceled. Subsequent to the Expiration Date, no shares of Common Stock need be reserved in respect of any unexercised Warrant.

11. Registration and Transfer of Warrant, Etc.

11.1. Warrant Register; Ownership of Warrant. Each Warrant issued by the Company shall be numbered and shall be registered in a warrant register (the “Warrant Register”) as it is issued and transferred, which Warrant Register shall be maintained by the Company at its principal office or, at the Company’s election and expense, by a Warrant Agent or the Company’s transfer agent. The Company shall be entitled to treat the registered Holder of any Warrant on the Warrant Register as the owner in fact thereof for all purposes and shall not be bound to recognize any equitable or other claim to or interest in such Warrant on the part of any other Person, and shall not be affected by any notice to the contrary, except that, if and when any Warrant is properly assigned in blank, the Company may (but shall not be obligated to) treat the bearer thereof as the owner of such Warrant for all purposes. Subject to Section 9, a Warrant, if properly assigned (or assigned by the Holder to any Related Fund (as defined in the Financing Agreement) or any other affiliate of the Holder), may be exercised by a new holder without a new Warrant first having been issued.

11.2. Transfer of Warrant. At any time after May 17, 2004 and subject to compliance with Section 9, if applicable, this Warrant and all rights hereunder are transferable in whole or in part, without charge to the Holder hereof, upon surrender of this Warrant with a properly executed Form of Assignment attached hereto as Exhibit B at the principal office of the Company. Upon any partial transfer, the Company shall at its expense issue and deliver to the Holder a new Warrant of like tenor, in the name of the Holder, which shall be exercisable for a number of shares of Common Stock with respect to which rights under this Warrant were not so transferred. Notwithstanding the first sentence of this Section 11.2 (including, without limitation, the restriction on transferability on or prior to May 17, 2004), at any time after the date hereof and subject to compliance with Section 9, this Warrant (or any part thereof) shall be freely transferable by the Holder to any Related Fund (as defined in the Financing Agreement) or any other affiliate of the Holder.

11.3. Replacement of Warrant. On receipt by the Company of evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this Warrant and, in the case of any such loss, theft or destruction of this Warrant, on delivery of an indemnity bond in such reasonable amount as the Company may determine, or, in the case of any such mutilation, on surrender of such Warrant to the Company at its principal office and

17

cancellation thereof, the Company at its expense shall execute and deliver, in lieu thereof, a new Warrant of like tenor. Applicants for such substitute Warrants shall also comply with such other reasonable regulations and pay such other reasonable charges as the Company may from time to time prescribe by giving notice thereof to the Holder.

11.4. Fractional Shares. Notwithstanding any provision of this Warrant, the Company shall not be required to issue fractions of shares upon exercise of this Warrant or to distribute certificates which evidence fractional shares. In lieu of fractional shares, the Company shall make payment to the Holder, at the time of exercise of this Warrant as herein provided, in an amount in cash equal to such fraction multiplied by the Exercise Price of a share of Common Stock on the date of Warrant exercise.

12. Remedies; Specific Performance. The Company stipulates that there would be no adequate remedy at law to the Holder of this Warrant in the event of any default or threatened default by the Company in the performance of or compliance with any of the terms of this Warrant and accordingly, the Company agrees that, in addition to any other remedy to which the Holder may be entitled at law or in equity, the Holder shall be entitled to seek to compel specific performance of the obligations of the Company under this Warrant, without the posting of any bond, in accordance with the terms and conditions of this Warrant in any court of the United States or any State thereof having jurisdiction, and if any action should be brought in equity to enforce any of the provisions of this Warrant, the Company shall not raise the defense that there is an adequate remedy at law. Except as otherwise provided by law, a delay or omission by the Holder hereto in exercising any right or remedy accruing upon any such breach shall not impair the right or remedy or constitute a waiver of or acquiescence in any such breach. No remedy shall be exclusive of any other remedy. All available remedies shall be cumulative.

13. No Rights or Liabilities as Shareholder. Nothing contained in this Warrant shall be construed as conferring upon the Holder hereof any rights as a shareholder of the Company or as imposing any obligation on the Holder to purchase any securities or as imposing any liabilities on the Holder as a shareholder of the Company, whether such obligation or liabilities are asserted by the Company or by creditors of the Company.

14. Notices. All notices and other communications (and deliveries) provided for or permitted hereunder shall be made in writing by hand delivery, telecopier, any courier guaranteeing overnight delivery or first class registered or certified mail, return receipt requested, postage prepaid, addressed: if to the Company, to the Company at its address at:

ATP Oil & Gas Corporation

4600 Post Oak Place

Suite 200

Houston, Texas 77027

Attention: Chief Financial Officer

Telephone: 713-622-3311

Telecopier: 713-622-5101

18

with a copy to:

ATP Oil & Gas Corporation

4600 Post Oak Place

Suite 200

Houston, Texas 77027

Attention: General Counsel

Telephone: 713-622-3311

Telecopier: 713-622-0289;

if to the Holder, at the address specified in the Financing Agreement; or as to any party, at such other address as shall be designated by such party in a written notice to the other party.

All such notices and communications (and deliveries) shall be deemed to have been duly given: at the time delivered by hand, if personally delivered; when receipt is acknowledged, if telecopied; on the next Business Day, if timely delivered to a courier guaranteeing overnight delivery; and five days after being deposited in the mail, if sent first class or certified mail, return receipt requested, postage prepaid; provided, that the exercise of any Warrant shall be effective in the manner provided in Section 2.

15. Amendments. This Warrant and any term hereof may not be amended, modified, supplemented or terminated, and waivers or consents to departures from the provisions hereof may not be given, except by written instrument duly executed by the party against which enforcement of such amendment, modification, supplement, termination or consent to departure is sought.

16. Descriptive Headings, Etc. The headings in this Warrant are for convenience of reference only and shall not limit or otherwise affect the meaning of terms contained herein. Unless the context of this Warrant otherwise requires: (1) words of any gender shall be deemed to include each other gender; (2) words using the singular or plural number shall also include the plural or singular number, respectively; (3) the words “hereof”, “herein” and “hereunder” and words of similar import when used in this Warrant shall refer to this Warrant as a whole and not to any particular provision of this Warrant, and Section and paragraph references are to the Sections and paragraphs of this Warrant unless otherwise specified; (4) the word “including” and words of similar import when used in this Warrant shall mean “including, without limitation,” unless otherwise specified; (5) “or” is not exclusive; and (6) provisions apply to successive events and transactions.

17. Governing Law. This Warrant shall be governed by, and construed in accordance with, the laws of the State of New York (without giving effect to the conflict of laws principles thereof, except Sections 5-1401 and 5-1402 of the New York General Obligations Law).

18. Judicial Proceedings. (a) Each of the parties hereto hereby irrevocably and unconditionally submits, for itself and its property, to the nonexclusive jurisdiction of any New York State court or federal court of the United States of America sitting in New York City, and any appellate court from any thereof, in any action or proceeding arising out of or relating to this Warrant, or for recognition or enforcement of any judgment, and each of the parties hereto

19

hereby irrevocably and unconditionally agrees that all claims in respect of any such action or proceeding may be heard and determined in any such New York State court or, to the extent permitted by law, in such federal court. Each of the parties hereto agrees that a final judgment in any such action or proceeding shall be conclusive and may be enforced in other jurisdictions by suit on the judgment or in any other manner provided by law. Nothing in this Agreement shall affect any right that any party may otherwise have to bring any action or proceeding relating to this Warrant in the courts of any jurisdiction.

(b) Each of the parties hereto irrevocably and unconditionally waives, to the fullest extent it may legally and effectively do so, any objection that it may now or hereafter have to the laying of venue of any suit, action or proceeding arising out of or relating to this Warrant in any New York State or federal court. Each of the parties hereto hereby irrevocably waives, to the fullest extent permitted by law, the defense of an inconvenient forum to the maintenance of such action or proceeding in any such court.

19. Waiver of Jury Trial. TO THE MAXIMUM EXTENT PERMITTED BY LAW, THE COMPANY AND THE HOLDER HEREBY IRREVOCABLY WAIVE TRIAL BY JURY IN ANY ACTION, SUIT OR PROCEEDING, WHETHER AT LAW OR EQUITY, BROUGHT BY IT OR THE HOLDER IN CONNECTION WITH THIS WARRANT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

20. Registration Rights Agreement. The shares of Common Stock (and Other Securities) issuable upon exercise of this Warrant (or upon conversion of any shares of Common Stock issued upon such exercise) shall constitute Registrable Securities (as such term is defined in the Registration Rights Agreement). Each Holder of this Warrant shall be entitled to all of the benefits afforded to a holder of any such Registrable Securities under the Registration Rights Agreement and such Holder, by its acceptance of this Warrant, agrees to be bound by and to comply with the terms and conditions of the Registration Rights Agreement applicable to such Holder as a holder of such Registrable Securities.

21. Call Rights. On or prior to May 17, 2004, and subject to the provisions of this Section 21, the Company shall have the right to purchase all (but not less than all) of this Warrant from the Holder. The Company may exercise its call right by providing written notice to the Holder (the “Call Notice”). Any exercise by the Company of its call right shall be irrevocable. The closing of the purchase by the Company, and the sale by the Holder, of this Warrant, following exercise by the Company of its call right (the “Call Closing”) shall be held at the principal office of Holder or its legal counsel on the second (2nd) business day following Holder’s receipt of the Company’s Call Notice; provided, however, that such date may not be later than May 17, 2004. At the Call Closing, Holder shall deliver this Warrant to the Company against receipt from the Company of the aggregate Call Price (as defined below) therefor in cash by wire transfer of immediately available funds to Holder’s designated account. As used herein: “Call Price” shall mean $637,500. If Holder tenders this Warrant at the Call Closing and the Company fails to tender payment of the required aggregate Call Price at the Call Closing, then the Company’s call right shall thereupon terminate and be of no force or effect, notwithstanding its previous exercise thereof, and the Company shall indemnify Holder against all costs, expenses (including without limitation reasonable attorneys’ fees), losses and damages paid, suffered or

20

incurred by Holder as a result of the Company’s exercise of such call right and failure to tender such aggregate Call Price.

22. Costs and Attorneys’ Fees. In the event that any action, suit or other proceeding is instituted concerning or arising out of this Warrant, the Corporation agrees and the Holder, by taking and holding this Warrant agrees, that the prevailing party shall recover from the non-prevailing party all of such prevailing party’s costs and reasonable attorneys’ fees incurred in each and every such action, suit or other proceeding, including any and all appeals or petitions therefrom.

23. Most Favorable Holder. The Company agrees that if at any time or from time to time prior to the Expiration Date it enters into any agreement with, or issues Options or Convertible Securities to, any Person other than a Holder of this Warrant, which provides such Person with more favorable terms of the type set forth in Sections 3, 4, 5 and 6 of this Warrant, then the Company shall issue to the Holder a new Warrant in exchange for this Warrant, which shall contain such terms, effective from the date such agreement is consummated or Option or Convertible Security is issued until the Expiration Date.

21

IN WITNESS WHEREOF, the Company has executed and delivered this Warrant to the Holder as of the date first above written.

ATP OIL & GAS CORPORATION
By:	/s/ T. Paul Bulmahn
	Name:
	Title:	President

[Signature Page to Warrant No. W-2 of ATP Oil & Gas Corporation]

22

EXHIBIT A to

Common Stock Purchase Warrant

FORM OF

ELECTION TO PURCHASE SHARES

The undersigned hereby irrevocably elects to exercise the Warrant to purchase                  shares of Common Stock, par value $.001 per share (“Common Stock”), of ATP OIL & GAS CORPORATION and hereby makes payment of $                 therefor in accordance with the terms of the Common Stock Purchase Warrant against delivery of stock certificates representing such shares. The undersigned hereby requests that certificates for such shares be issued and delivered as follows:

ISSUE TO:

	(NAME)
	(ADDRESS, INCLUDING ZIP CODE)
	(SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER)
DELIVER TO:
	(NAME)
	(ADDRESS, INCLUDING ZIP CODE)

If the number of shares of Common Stock purchased (and/or reduced) hereby is less than the total number of Shares then covered by the Warrant, the undersigned requests that this Warrant, which shall note the number of shares of Common Stock issued to date, be delivered to the holder as follows:

ISSUE TO:

	(NAME OF HOLDER)
	(ADDRESS, INCLUDING ZIP CODE)
DELIVER TO:
	(NAME OF HOLDER)
	(ADDRESS, INCLUDING ZIP CODE)

Dated:                     , 200  

NAME OF HOLDER1
By
	Name:
	Title:

¹ Name of Holder must conform in all respects to name of holder as specified on the face of the Warrant.

EXHIBIT B to

Common Stock Purchase Warrant

FORM OF ASSIGNMENT

FOR VALUE RECEIVED, the undersigned hereby sells, assigns, and transfers unto the Assignee named below all of the rights of the undersigned to purchase Common Stock, par value $.001 per share (“Common Stock”), of ATP OIL & GAS CORPORATION represented by the Warrant, with respect to the number of shares of Common Stock set forth below:

Name of Assignee Address Number of Shares

and does hereby irrevocably constitute and appoint                  Attorney to make such transfer on the books of ATP OIL & GAS CORPORATION maintained for that purpose, with full power of substitution in the premises.

Dated:                     , 200	NAME OF HOLDER1
	By
		Name:
		Title:

¹ Name of Holder must conform in all respects to name of holder as specified on the face of the Warrant.

EX-4.3

Exhibit 4.3

WARRANT

THIS WARRANT AND ANY SECURITIES ACQUIRED UPON EXERCISE OF THIS WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS OF ANY STATE AND MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND APPLICABLE STATE SECURITIES LAWS OR PURSUANT TO AN APPLICABLE EXEMPTION TO THE REGISTRATION REQUIREMENTS OF SUCH ACT AND SUCH LAWS. THIS WARRANT AND SUCH SECURITIES MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT IN COMPLIANCE WITH THE CONDITIONS SPECIFIED IN THIS WARRANT.

THIS WARRANT AND THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO THE TERMS AND CONDITIONS OF A REGISTRATION RIGHTS AGREEMENT DATED AS OF FEBRUARY 16, 2004.

THIS WARRANT AND THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO THE TERMS AND CONDITIONS OF A FINANCING AGREEMENT DATED AS OF AUGUST, 13, 2003, AS AMENDED. IN NO EVENT SHALL THIS WARRANT BE EXERCISABLE ON OR PRIOR TO MAY 17, 2004.

ATP OIL & GAS CORPORATION

COMMON STOCK PURCHASE WARRANT

No. W-1 February 16, 2004

Warrant to Purchase

112,500 Shares of Common Stock

ATP OIL & GAS CORPORATION, a Texas corporation (the “Company”), for value received, hereby certifies that WELLS FARGO FOOTHILL, INC. or its registered assigns (the “Holder”), is entitled to purchase from the Company duly authorized, validly issued, fully paid and nonassessable shares of Common Stock, par value $.001 per share, of the Company (the “Common Stock”), at a purchase price per share equal to the Exercise Price, at any time or from time to time on or after May 17, 2004, but prior to 5:00 P.M., New York City time, on February 16, 2009 (the “Expiration Date”), all subject to the terms, conditions and adjustments set forth below in this Warrant.

1

This Warrant is one of the Common Stock Purchase Warrants (the “Warrant” and, collectively, the “Warrants,” such terms to include any such warrants issued in substitution therefor) referred to and issued under that certain Second Amended and Restated Financing Agreement, dated as of August 13, 2003, as amended pursuant to the Consent and Amendment No. 1, dated as of November 14, 2003, Amendment No. 2, dated as of December 3, 2003, and as supplemented by the Joinder Agreement, dated as of December 3, 2003, and Amendment No. 3, dated as of February 16, 2004 (as amended, supplemented or otherwise modified from time to time, the “Financing Agreement”), by and among the Company, as the borrower, each subsidiary of the Company listed as a guarantor on the signature pages thereto, each of the lenders from time to time party thereto, Ableco Finance LLC, as collateral agent and administrative agent for the lenders, and Wells Fargo Foothill, Inc., as funding agent for the lenders. The Warrant originally so issued evidences the right to purchase up to 112,500 shares of Common Stock (the “Initial Number of Shares”), subject to certain adjustments as provided herein. Capitalized terms used herein and not otherwise defined herein shall have the meanings assigned such terms in the Financing Agreement.

1. Definitions. As used herein, unless the context otherwise requires, the following terms shall have the meanings indicated:

“Additional Shares of Common Stock” shall mean (without duplication) all shares (including treasury shares) of Common Stock issued or sold (or, pursuant to Section 3.3 or 3.4, deemed to be issued) by the Company after the date hereof, whether or not subsequently reacquired or retired by the Company, other than (a) shares issued upon the exercise of this Warrant or any other Warrant issued in connection with the Financing Agreement and (b) such number of additional shares as may become issuable upon the exercise of the Warrants by reason of adjustments required pursuant to the provisions of such Warrants as in effect on the date hereof.

“Applicable Number of Shares” shall mean at any date of determination a number of shares of Common Stock equal to the difference between (a) the Initial Number of Shares, less (b) the number of shares of Common Stock which were issued pursuant to the exercise of this Warrant, as determined immediately prior to such date (giving effect to any stock splits or combinations, or any dividends paid or payable in shares of Common Stock, after the issuance of such shares).

“Business Day” shall mean any day other than a Saturday or a Sunday or a day on which commercial banking institutions in the City of New York are authorized by law to be closed. Any reference to “days” (unless Business Days are specified) shall mean calendar days.

“Commission” shall mean the Securities and Exchange Commission or any successor agency having jurisdiction to enforce the Securities Act.

“Common Stock” shall have the meaning assigned to it in the introduction to this Warrant, such term to include any stock into which the Common Stock shall have been changed or any stock resulting from any reclassification of such Common Stock, and all other stock of any class or classes (however designated) of the Company the holders of which have the right,

2

without limitation as to amount, either to all or to a share of the balance of current dividends and liquidating dividends after the payment of dividends and distributions on any shares entitled to preference.

“Company” shall have the meaning assigned to it in the introduction to this Warrant, such term to include any corporation or other entity which shall succeed to or assume the obligations of the Company hereunder in compliance with Section 4.

“Convertible Securities” shall mean any evidences of indebtedness, shares of stock (other than Common Stock) or other securities directly or indirectly convertible into or exchangeable for Additional Shares of Common Stock.

“Current Market Price” shall mean, on any date specified herein, the average of the daily Market Price during the 5 consecutive trading days before such date, except that, if on any such date the shares of Common Stock are not listed or admitted for trading on any national securities exchange or quoted in the over-the-counter market, the Current Market Price shall be the Market Price on such date.

“Exchange Act” shall mean the Securities Exchange Act of 1934, as amended from time to time, and the rules and regulations thereunder, or any successor statute.

“Exercise Price” shall mean the Initial Price, as adjusted from time to time as provided herein.

“Expiration Date” shall have the meaning assigned to it in the introduction to this Warrant.

“Fair Value” shall mean, on any date specified herein (i) in the case of cash, the dollar amount thereof, (ii) in the case of a security, the Market Price, and (iii) in all other cases, the fair value thereof (as of a date which is within 20 days of the date as of which the determination is to be made) determined in good faith jointly by the Company and a Majority of the Holders; provided, however, that if such parties are unable to reach agreement within a reasonable period of time, the Fair Value shall be determined in good faith, by an independent investment banking firm selected jointly by the Company and a Majority of the Holders or, if that selection cannot be made within ten days, by an independent investment banking firm selected by the American Arbitration Association in accordance with its rules, and provided further, that the Company shall pay all of the fees and expenses of any third parties incurred in connection with determining the Fair Value.

“Financing Agreement” shall have the meaning assigned to it in the introduction to this Warrant.

“Financing Agreement Date” shall mean February 16, 2004.

“Holder” shall have the meaning assigned to it in the introduction to this Warrant.

3

“Initial Number of Shares” shall have the meaning assigned to it in the introduction to this Warrant.

“Initial Price” means $6.75.

“Majority of the Holders” shall mean the Holders of this Warrant and any other Warrants issued pursuant to the Financing Agreement who shall be entitled, upon exercise of their Warrants, to purchase more than 50% of all shares of Common Stock then issuable under all such Warrants.

“Market Price” shall mean, on any date specified herein, the amount per share of the Common Stock, equal to (a) the last reported sale price of such Common Stock, regular way, on such date or, in case no such sale takes place on such date, the average of the closing bid and asked prices thereof regular way on such date, in either case as officially reported on the principal national securities exchange on which such Common Stock is then listed or admitted for trading, (b) if such Common Stock is not then listed or admitted for trading on any national securities exchange but is designated as a national market system security by the NASD, the last reported trading price of the Common Stock on such date, (c) if there shall have been no trading on such date or if the Common Stock is not so designated, the average of the closing bid and asked prices of the Common Stock on such date as shown by the NASD automated quotation system, or (d) if such Common Stock is not then listed or admitted for trading on any national exchange or quoted in the over-the-counter market, the fair value thereof (as of a date which is within 20 days of the date as of which the determination is to be made) determined in good faith jointly by the Company and a Majority of the Holders; provided, however, that if such parties are unable to reach agreement within a reasonable period of time, the Market Price shall be determined in good faith by an independent investment banking firm selected jointly by the Company and a Majority of the Holders or, if that selection cannot be made within ten days, by an independent investment banking firm selected by the American Arbitration Association in accordance with its rules, and provided further, that the Company shall pay all of the fees and expenses of any third parties incurred in connection with determining the Market Price.

“NASD” shall mean the National Association of Securities Dealers, Inc.

“Notice” shall have the meaning assigned to it in Section 2.1(a) of this Agreement.

“Options” shall mean any rights, options or warrants to subscribe for, purchase or otherwise acquire Additional Shares of Common Stock or Convertible Securities.

“Other Securities” shall mean any stock (other than Common Stock) and other securities of the Company or any other Person (corporate or otherwise) which the holders of the Warrants at any time shall be entitled to receive, or shall have received, upon the exercise of the Warrants, in lieu of or in addition to Common Stock, or which at any time shall be issuable or shall have been issued in exchange for or in replacement of Common Stock or Other Securities pursuant to Section 4 or otherwise.

4

“Permitted Issuances” shall mean any issuance of capital stock of the Company which constitutes a Permitted Preferred Equity Issuance (as such term is defined in Amendment No. 3, dated February 16, 2004, to the Financing Agreement).

“Person” shall mean any individual, firm, partnership, corporation, trust, joint venture, association, joint stock company, limited liability company, unincorporated organization or any other entity or organization, including a government or agency or political subdivision thereof, and shall include any successor (by merger or otherwise) of such entity.

“Purchase Price” shall have the meaning assigned to it in Section 2.1(a) of this Agreement.

“Registration Rights Agreement” means that certain Registration Rights Agreement, dated the date hereof, by and between the Company thereof and each Holder, as may be amended from time to time, including the demand and piggy-back registration rights of the Holders and the other provisions thereof with respect to the Warrants and the shares of Common Stock issuable upon the exercise of the Warrants.

“Restricted Securities” shall mean (a) any Warrants bearing the applicable legend set forth in Section 9.1, (b) any shares of Common Stock (or Other Securities) issued or issuable upon the exercise of Warrants which are (or, upon issuance, will be) evidenced by a certificate or certificates bearing the applicable legend set forth in such Section, and (c) any shares of Common Stock (or Other Securities) issued subsequent to the exercise of any of the Warrants as a dividend or other distribution with respect to, or resulting from a subdivision of the outstanding shares of Common Stock (or other Securities) into a greater number of shares by reclassification, stock splits or otherwise, or in exchange for or in replacement of the Common Stock (or Other Securities) issued upon such exercise, which are evidenced by a certificate or certificates bearing the applicable legend set forth in such Section.

“Securities Act” shall mean the Securities Act of 1933, as amended from time to time, and the rules and regulations thereunder, or any successor statute.

“Warrant or Warrants” shall have the meaning assigned to it in the introduction to this Warrant.

2. Exercise of Warrant.

2.1. Manner of Exercise; Payment of the Purchase Price. (a) This Warrant may be exercised by the Holder hereof, in whole or in part, at any time or from time to time on or after May 17, 2004 but prior to the Expiration Date, for a number of shares of Common Stock not greater than the then-Applicable Number of Shares determined as of the date of exercise, by surrendering to the Company at its principal office this Warrant, with the form of Election to Purchase Shares (the “Notice”) attached hereto as Exhibit A (or a reasonable facsimile thereof) duly executed by the Holder, which Notice shall specify the number of shares of Common Stock to be issued to such Holder and accompanied by payment of the applicable purchase price (the

5

“Purchase Price”) in an amount equal to the product of (i) the Exercise Price and (ii) the number of shares of Common Stock to be issued.

(b) Payment of the Purchase Price may be made as follows (or by any combination of the following): (i) in United States currency by cash or delivery of a certified check or bank draft payable to the order of the Company or by wire transfer to the Company, (ii) by cancellation of all or any part of the unpaid principal amount of the then-outstanding Obligations (as defined in the Financing Agreement) in an amount equal to the Purchase Price, (iii) by cancellation of such number of the shares of Common Stock otherwise issuable to the Holder upon such exercise as shall be specified in such Election to Purchase Shares, such that the excess of the aggregate Current Market Price of such specified number of shares on the date of exercise over the portion of the Purchase Price attributable to such shares shall equal the Purchase Price attributable to the shares of Common Stock to be issued upon such exercise, in which case such amount shall be deemed to have been paid to the Company and the number of shares issuable upon such exercise shall be reduced by such specified number, (iv) by surrender to the Company for cancellation certificates representing shares of Common Stock of the Company owned by the Holder (properly endorsed for transfer in blank) having a Current Market Price on the date of Warrant exercise equal to the Purchase Price, or (v) by a combination of the methods described in clauses (i), (ii), (iii) and (iv).

2.2. When Exercise Effective. Each exercise of this Warrant shall be deemed to have been effected as of the later to occur of (a) receipt of payment of the Purchase Price and (b) immediately prior to the close of business on the Business Day on which this Warrant shall have been surrendered to the Company as provided in Section 2.1, and at such time of effectiveness the Person or Persons in whose name or names any certificate or certificates for shares of Common Stock (or Other Securities) shall be issuable upon such exercise as provided in Section 2.3 shall be deemed to have become the holder or holders of record thereof for all purposes.

2.3. Delivery of Stock Certificates, etc.; Charges, Taxes and Expenses. (a) As soon as practicable after each exercise of this Warrant, in whole or in part, and in any event within five Business Days thereafter, the Company shall cause to be issued in the name of and delivered to the Holder hereof or, subject to Section 10, as the Holder may direct, a certificate or certificates for the number of shares of Common Stock (or Other Securities) to which the Holder shall be entitled upon such exercise plus, in lieu of issuance of any fractional share to which the Holder would otherwise be entitled, if any, a check for the amount of cash equal to the same fraction multiplied by the Exercise Price per share on the date of Warrant exercise.

In case any such exercise is for less than all of the then-Applicable Number of Shares as of the date of exercise purchasable under this Warrant, this Warrant or a new Warrant or Warrants of like tenor, shall be returned to the Holder, noting the number of shares of Common Stock issued hereunder to date.

The Company will pay all documentary stamp taxes attributable to the initial issuance of shares of Common Stock upon the exercise of Warrants; provided, however, that the Company shall not be required to pay any tax or taxes which may be payable in respect of any

6

transfer involved in the issue of any Warrants or any certificates for shares of Common stock in a name other than that of the Holder, and the Company shall not be required to issue or deliver such Warrant or shares of Common Stock unless or until the person or persons requesting the issuance thereof shall have paid to the Company the amount of such tax or shall have established to the satisfaction of the Company that such tax has been paid.

3. Adjustment of Common Stock Issuable Upon Exercise; Adjustment of Exercise Price.

3.1. Adjustment of Number of Shares. From and after the date hereof, upon each adjustment of the Exercise Price as a result of the calculations made in this Section 3, this Warrant shall thereafter evidence the right to receive, at the adjusted Exercise Price, that number of shares of Common Stock (calculated to the nearest one-hundredth) obtained by dividing (i) the product of the aggregate number of shares covered by this Warrant immediately prior to such adjustment and the Exercise Price in effect immediately prior to such adjustment of the Exercise Price by (ii) the Exercise Price in effect immediately after such adjustment of the Exercise Price.

3.2. Adjustment of Exercise Price.

3.2.1. Issuance of Additional Shares of Common Stock. In case the Company at any time or from time to time after the Financing Agreement Date shall issue or sell Additional Shares of Common Stock (including Additional Shares of Common Stock deemed to be issued pursuant to Section 3.3 or 3.4) without consideration or for a consideration per share less than the Market Price in effect immediately prior to such issue or sale, then, and in each such case (other than issuances pursuant to this Section 3.2.1 consented to in advance by a majority of the Holders and Permitted Issuances), subject to Section 3.8, the Exercise Price shall be reduced, concurrently with such issue or sale, to a price (calculated to the nearest .001 of a cent) determined by multiplying such Exercise Price by a fraction

(a) the numerator of which shall be the sum of (i) the number of shares of Common Stock outstanding immediately prior to such issue or sale and (ii) the number of shares of Common Stock which the aggregate consideration received by the Company for the total number of such Additional Shares of Common Stock so issued or sold would purchase at such Market Price, and

(b) the denominator of which shall be the number of shares of Common Stock outstanding immediately after such issue or sale, provided, however, that, for the purposes of this Section 3.2.1, (x) immediately after any Additional Shares of Common Stock are deemed to have been issued pursuant to Section 3.3 or 3.4, such Additional Shares shall be deemed to be outstanding, and (y) treasury shares shall not be deemed to be outstanding.

3.2.2. Extraordinary Dividends and Distributions. In case the Company at any time or from time to time after the Financing Agreement Date shall declare, order, pay or make a dividend (excluding dividends consented to in advance by the majority of the Holders) or other distribution (including, without limitation, any distribution of other or additional stock or other

7

securities or property or Options by way of dividend or spin-off, reclassification, recapitalization or similar corporate rearrangement) on the Common Stock, subject to Section 3.8, the Exercise Price in effect immediately prior to the close of business on the record date fixed for the determination of holders of any class of securities entitled to receive such dividend or distribution shall be reduced, effective as of the close of business on such record date, to a price determined by multiplying such Exercise Price by a fraction

(x) the numerator of which shall be the Market Price in effect on such record date or, if the Common Stock trades on an ex-dividend basis, on the date prior to the commencement of ex-dividend trading, less the Fair Value of such dividend or distribution applicable to one share of Common Stock, and

(y) the denominator of which shall be such Market Price.

3.3. Treatment of Options and Convertible Securities. In case the Company at any time or from time to time after the Financing Agreement Date shall issue, sell, grant or assume, or shall fix a record date for the determination of holders of any class of securities of the Company entitled to receive, any Options or Convertible Securities (whether or not the rights thereunder are immediately exercisable), then, and in each such case, the maximum number of Additional Shares of Common Stock (as set forth in the instrument relating thereto, without regard to any provisions contained therein for a subsequent adjustment of such number) issuable upon the exercise of such Options or, in the case of Convertible Securities and Options therefor, or the conversion or exchange of such Convertible Securities, shall be deemed to be Additional Shares of Common Stock issued as of the time of such issue, sale, grant or assumption or, in case such a record date shall have been fixed, as of the close of business on such record date (or, if the Common Stock trades on an ex-dividend basis, on the date prior to the commencement of ex-dividend trading), provided, however, that such Additional Shares of Common Stock shall not be deemed to have been issued unless the consideration per share (determined pursuant to Section 3.5) of such shares would be less than the Market Price in effect on the date of and immediately prior to such issue, sale, grant or assumption or immediately prior to the close of business on such record date (or, if the Common Stock trades on an ex-dividend basis, on the date prior to the commencement of ex-dividend trading), as the case may be and provided, further, that in any such case in which Additional Shares of Common Stock are deemed to be issued:

(a) whether or not the Additional Shares of Common Stock underlying such Options or Convertible Securities are deemed to be issued, no further adjustment of the Exercise Price shall be made upon the subsequent issue or sale of Convertible Securities or shares of Common Stock upon the exercise of such Options or the conversion or exchange of such Convertible Securities, except in the case of any such Options or Convertible Securities which contain provisions requiring an adjustment, subsequent to the date of the issue or sale thereof, of the number of Additional Shares of Common Stock issuable upon the exercise of such Options or the conversion or exchange of such Convertible Securities by reason of (x) a change of control of the Company, (y) the acquisition by any Person or group of Persons of any specified number or percentage of the voting securities of the Company or (z) any similar event or occurrence, each such

8

case to be deemed hereunder to involve a separate issuance of Additional Shares of Common Stock, Options or Convertible Securities, as the case may be;

(b) if such Options or Convertible Securities by their terms provide, with the passage of time or otherwise, for any increase in the consideration payable to the Company, or decrease in the number of Additional Shares of Common Stock issuable, upon the exercise, conversion or exchange thereof (by change of rate or otherwise), the Exercise Price computed upon the original issue, sale, grant or assumption thereof (or upon the occurrence of the record date, or date prior to the commencement of ex-dividend trading, as the case may be, with respect thereto), and any subsequent adjustments based thereon, shall, upon any such increase or decrease becoming effective, be recomputed to reflect such increase or decrease insofar as it affects such Options, or the rights of conversion or exchange under such Convertible Securities, which are outstanding at such time;

(c) upon the expiration (or purchase by the Company and cancellation or retirement) of any such Options which shall not have been exercised or the expiration of any rights of conversion or exchange under any such Convertible Securities which (or purchase by the Company and cancellation or retirement of any such Convertible Securities the rights of conversion or exchange under which) shall not have been exercised, the Exercise Price computed upon the original issue, sale, grant or assumption thereof (or upon the occurrence of the record date, or date prior to the commencement of ex-dividend trading, as the case may be, with respect thereto), and any subsequent adjustments based thereon, shall, upon such expiration (or such cancellation or retirement, as the case may be), be recomputed as if:

(i) in the case of Options for Common Stock or Convertible Securities, the only Additional Shares of Common Stock issued or sold were the Additional Shares of Common Stock, if any, actually issued or sold upon the exercise of such Options or the conversion or exchange of such Convertible Securities and the consideration received therefor was the consideration actually received by the Company for the issue, sale, grant or assumption of all such Options, whether or not exercised, plus the consideration actually received by the Company upon such exercise, or for the issue or sale of all such Convertible Securities which were actually converted or exchanged, plus the additional consideration, if any, actually received by the Company upon such conversion or exchange, and

(ii) in the case of Options for Convertible Securities, only the Convertible Securities, if any, actually issued or sold upon the exercise of such Options were issued at the time of the issue or sale, grant or assumption of such Options, and the consideration received by the Company for the Additional Shares of Common Stock deemed to have then been issued was the consideration actually received by the Company for the issue, sale, grant or assumption of all such Options, whether or not exercised, plus the consideration deemed to have been received by the Company (pursuant to Section 3.5) upon the issue or sale of such

9

Convertible Securities with respect to which such Options were actually exercised;

(d) no readjustment pursuant to subdivision (b) or (c) above shall have the effect of increasing the Exercise Price by an amount in excess of the amount of the adjustment thereof originally made in respect of the issue, sale, grant or assumption of such Options or Convertible Securities; and

(e) in the case of any such Options which expire by their terms not more than 30 days after the date of issue, sale, grant or assumption thereof, no adjustment of the Exercise Price shall be made until the expiration or exercise of all such Options, whereupon such adjustment shall be made in the manner provided in subdivision (c) above.

3.4. Treatment of Stock Dividends, Stock Splits, etc. In case the Company at any time or from time to time after the Financing Agreement Date shall declare or pay any dividend on the Common Stock payable in Common Stock, or shall effect a subdivision of the outstanding shares of Common Stock into a greater number of shares of Common Stock (by reclassification or otherwise than by payment of a dividend in Common Stock), then, and in each such case, Additional Shares of Common Stock shall be deemed to have been issued (a) in the case of any such dividend, immediately after the close of business on the record date for the determination of holders of any class of securities entitled to receive such dividend, or (b) in the case of any such subdivision, at the close of business on the day immediately prior to the day upon which such corporate action becomes effective.

3.5. Computation of Consideration. For the purposes of this Section 3,

(a) the consideration for the issue or sale of any Additional Shares of Common Stock shall, irrespective of the accounting treatment of such consideration,

(i) insofar as it consists of cash, be computed at the net amount of cash received by the Company, without deducting any expenses paid or incurred by the Company or any commissions or compensations paid or concessions or discounts allowed to underwriters, dealers or others performing similar services in connection with such issue or sale,

(ii) insofar as it consists of property (including securities) other than cash, be computed at the Fair Value thereof at the time of such issue or sale, and

(iii) in case Additional Shares of Common Stock are issued or sold together with other stock or securities or other assets of the Company for a consideration which covers both, be the portion of such consideration so received, computed as provided in clauses (i) and (ii) above, allocable to such Additional Shares of Common Stock, such allocation to be determined in the same manner that the Fair Value of property not consisting of cash or securities is to be determined as provided in the definition of “Fair Value” herein;

10

(b) Additional Shares of Common Stock deemed to have been issued pursuant to Section 3.3, relating to Options and Convertible Securities, shall be deemed to have been issued for a consideration per share determined by dividing

(i) the total amount, if any, received and receivable by the Company as consideration for the issue, sale, grant or assumption of the Options or Convertible Securities in question, plus the minimum aggregate amount of additional consideration (as set forth in the instruments relating thereto, without regard to any provision contained therein for a subsequent adjustment of such consideration to protect against dilution) payable to the Company upon the exercise in full of such Options or the conversion or exchange of such Convertible Securities or, in the case of Options for Convertible Securities, the exercise of such Options for Convertible Securities and the conversion or exchange of such Convertible Securities, in each case computing such consideration as provided in the foregoing subdivision (a),

by

(ii) the maximum number of shares of Common Stock (as set forth in the instruments relating thereto, without regard to any provision contained therein for a subsequent adjustment of such number to protect against dilution) issuable upon the exercise of such Options or the conversion or exchange of such Convertible Securities; and

(c) Additional Shares of Common Stock deemed to have been issued pursuant to Section 3.4, relating to stock dividends, stock splits and similar corporate events shall be deemed to have been issued for no consideration.

3.6. Adjustments for Combinations, etc. If after the Financing Agreement Date the outstanding shares of Common Stock shall be combined or consolidated, by reclassification or otherwise, into a lesser number of shares of Common Stock, the Exercise Price in effect immediately prior to such combination or consolidation shall, concurrently with the effectiveness of such combination or consolidation, be proportionately increased.

3.7. Dilution in Case of Other Securities. If after the Financing Agreement Date any Other Securities shall be issued or sold or shall become subject to issue or sale upon the conversion or exchange of any stock (or Other Securities) of the Company (or any issuer of Other Securities or any other Person referred to in Section 4) or to subscription, purchase or other acquisition pursuant to any Options issued or granted by the Company (or any such other issuer or Person) for a consideration such as to dilute, on a basis consistent with the standards established in the other provisions of this Section 3, the purchase rights granted by this Warrant, then, and in each such case, the computations, adjustments and readjustments provided for in this Section 3 with respect to the Exercise Price shall be made as nearly as possible in the manner so provided and applied to determine the amount of Other Securities from time to time receivable upon the exercise of the Warrants, so as to protect the holders of the Warrants against the effect of such dilution.

11

3.8. De Minimis Adjustments; Certain Retroactive Adjustments. If the amount of any adjustment of the Exercise Price per share required pursuant to this Section 3 would be less than one tenth (1/10) of one percent (1%) of the Exercise Price, such amount shall be carried forward and adjustment with respect thereto made at the time of and together with any subsequent adjustment which, together with such amount and any other amount or amounts so carried forward, shall aggregate a change in the Exercise Price of at least one tenth (1/10) of one percent (1%) of such Exercise Price. All calculations under this Warrant shall be made to the nearest .001 of a cent or to the nearest one-hundredth of a share, as the case may be.

3.9. Abandoned Dividend or Distribution. If after the Financing Agreement Date the Company shall take a record of the holders of its Common Stock for the purpose of entitling them to receive a dividend or other distribution (which results in an adjustment to the Exercise Price under the terms of this Warrant) and shall, thereafter, and before such dividend or distribution is paid or delivered to shareholders entitled thereto, legally abandon its plan to pay or deliver such dividend or distribution, then any adjustment made to the Exercise Price by reason of the taking of such record shall be reversed, and any subsequent adjustments, based thereon, shall be recomputed.

4. Consolidation, Merger, Etc.

4.1. Adjustments for Consolidation, Merger, Sale of Assets, Reorganization, etc. In case the Company (a) shall consolidate with or merge into any other Person and shall not be the continuing or surviving corporation of such consolidation or merger, or (b) shall permit any other Person to consolidate with or merge into the Company and the Company shall be the continuing or surviving Person but, in connection with such consolidation or merger, the Common Stock or Other Securities shall be changed into or exchanged for stock or other securities of any other Person or cash or any other property, or (c) shall transfer all or substantially all of its properties or assets to any other Person and shall thereafter distribute any material portion of the proceeds of such transaction to its shareholders generally, or (d) shall effect a capital reorganization or reclassification of the Common Stock or Other Securities (other than a capital reorganization or reclassification of the Common Stock resulting in the issuance of Additional Shares of Common Stock for which adjustment in the Purchase Price is provided in Section 3.2.1 or 3.2.2), then, and in the case of each such transaction, proper provision shall be made so that, upon the basis and the terms and in the manner provided in this Warrant, the Holder of this Warrant, upon the exercise hereof at any time after the consummation of such transaction, shall be entitled to receive (at the aggregate Purchase Price in effect immediately prior to the time of such consummation for all Common Stock or Other Securities issuable upon such exercise immediately prior to such consummation), in lieu of the Common Stock or Other Securities issuable upon such exercise prior to such consummation, the highest amount of securities, cash or other property to which such Holder would actually have been entitled as a shareholder upon such consummation if such Holder had exercised this Warrant for all of the then-Applicable Number of Shares immediately prior thereto, subject to adjustments (subsequent to such consummation) as nearly equivalent as possible to the adjustments provided for in Sections 3 through 5.

12

4.2. Assumption of Obligations. Notwithstanding anything contained in the Warrants or in the Financing Agreement to the contrary, the Company shall not effect any of the transactions described in clauses (a) through (d) of Section 4.1 unless, prior to the consummation thereof, each Person (other than the Company) which may be required to deliver any stock, securities, cash or property upon the exercise of this Warrant as provided herein shall assume, by written instrument delivered to the Holder of this Warrant, (a) the obligations of the Company under this Warrant (and if the Company shall survive the consummation of such transaction, such assumption shall be in addition to, and shall not release the Company from, any continuing obligations of the Company under this Warrant), (b) the obligations of the Company under the Registration Rights Agreement and (c) the obligation to deliver to the Holder such shares of stock, securities, cash or property as, in accordance with the foregoing provisions of this Section 4, the Holder may be entitled to receive and such Person shall have similarly delivered to the Holder an opinion of counsel for such person, which counsel shall be reasonably satisfactory to the Holder, stating that this Warrant shall thereafter continue in full force and effect and the terms hereof (including, without limitation, all of the provisions of this Section 4) shall be applicable to the stock, securities, cash or property which such person may be required to deliver upon any exercise of this Warrant or the exercise of any rights pursuant thereto. Nothing in this Section 4 shall be deemed to authorize the Company to enter into any transaction not otherwise permitted by the Financing Agreement.

5. Other Dilutive Events. In case any event shall occur as to which the provisions of Section 3 or Section 4 are not strictly applicable or if strictly applicable would not, in the reasonable judgment of the Board of Directors, fairly protect the purchase rights represented by this Warrant in accordance with the essential intent and principles of such Sections, then, in each such case, the Board of Directors of the Company shall, in good faith, make an adjustment in the application of such provisions, in accordance with the essential intent and principles hereof, so as to preserve, without dilution, the purchase rights represented by this Warrant.

6. No Dilution or Impairment. The Company shall not, by amendment of its Articles of Incorporation or through any consolidation, merger, reorganization, transfer of assets, dissolution, issue or sale of securities or any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms of this Warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all such action as may be necessary or appropriate in order to protect the rights of the Holder of this Warrant against dilution or other impairment in accordance with the terms hereof. Without limiting the generality of the foregoing, the Company (a) shall not permit the par value of any shares of stock receivable upon the exercise of this Warrant to exceed the amount payable therefor upon such exercise, (b) shall take all such action as may be necessary or appropriate in order that the Company may validly and legally issue fully paid and nonassessable shares of stock, free from all taxes, liens, security interests, encumbrances, preemptive rights and charges on the exercise of the Warrants from time to time outstanding, and (c) shall not amend or modify any provision of the Articles of Incorporation or by-laws of the Company in any manner that would adversely affect in any way the rights or powers of the Holder of this Warrant in its capacity as such.

13

7. Notices of Corporate Action. In the event of:

(a) any taking by the Company of a record of the holders of any class of securities for the purpose of determining the holders thereof who are entitled to receive any dividend or other distribution, or any right to subscribe for, purchase or otherwise acquire any shares of stock of any class or any other securities or property, or to receive any other right, or

(b) any capital reorganization of the Company, any reclassification or recapitalization of the capital stock of the Company, any consolidation or merger involving the Company and any other Person, any transaction or series of transactions in which more than 50% of the voting securities of the Company are transferred to another Person, or any transfer, sale or other disposition of all or substantially all the assets of the Company to any other Person, or

(c) any voluntary or involuntary dissolution, liquidation or winding-up of the Company,

the Company shall mail to each holder of a Warrant a notice specifying (i) the date or expected date on which any such record is to be taken for the purpose of such dividend, distribution or right, and the amount and character of such dividend, distribution or right, and (ii) the date or expected date on which any such reorganization, reclassification, recapitalization, consolidation, merger, transfer, sale, disposition, dissolution, liquidation or winding-up is to take place and the time, if any such time is to be fixed, as of which the holders of record of Common Stock (or Other Securities) shall be entitled to exchange their shares of Common Stock (or Other Securities) for the securities or other property deliverable upon such reorganization, reclassification, recapitalization, consolidation, merger, transfer, dissolution, liquidation or winding-up. In the case of any action covered by clause (a) above, such notice shall be mailed by the Company at least 10 days prior to the date on which such record is to be taken, and, in the case of any action covered by clause (b) or (c) above, such notice shall be mailed by the Company at least 20 days prior to the date or expected date on which such action is to take place.

8. Listing of Common Stock. At any such time as Common Stock is listed on any national securities exchange, the Company shall, at its expense, obtain promptly and maintain the approval for listing on the principal such exchange, upon official notice of issuance, the shares of Common Stock issuable upon exercise of the then outstanding Warrants and maintain the listing of such shares after their issuance; and the Company shall also list on such national securities exchange and shall maintain such listing of, any Other Securities that at any time are issuable upon exercise of the Warrants, if and at the time that any securities of the same class shall be listed on such national securities exchange by the Company.

14

9. Restrictions on Transfer.

9.1. Restrictive Legends. Except as otherwise permitted by this Section 9, each Warrant (including each Warrant issued upon the transfer of any Warrant) shall be stamped or otherwise imprinted with a legend in substantially the following form:

“THIS WARRANT AND ANY SECURITIES ACQUIRED UPON THE EXERCISE OF THIS WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS OF ANY STATE, AND MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND APPLICABLE STATE SECURITIES LAWS OR PURSUANT TO AN APPLICABLE EXEMPTION TO THE REGISTRATION REQUIREMENTS OF SUCH ACT AND SUCH LAWS. THIS WARRANT AND SUCH SECURITIES MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT IN COMPLIANCE WITH THE CONDITIONS SPECIFIED IN THIS WARRANT.”

“THIS WARRANT AND THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO THE TERMS AND CONDITIONS OF A REGISTRATION RIGHTS AGREEMENT DATED AS OF FEBRUARY 16, 2004, AS SUCH AGREEMENT MAY BE AMENDED, MODIFIED, SUPPLEMENTED, RESTATED OR OTHERWISE CHANGED FROM TIME TO TIME.”

Except as otherwise permitted by this Section 9, during the term of the Financing Agreement, each Warrant (including each Warrant issued upon the transfer of any Warrant) shall be stamped or otherwise imprinted with a legend in substantially the following form:

“THIS WARRANT AND THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO THE TERMS AND CONDITIONS OF A FINANCING AGREEMENT DATED AS OF AUGUST 13, 2003, AS SUCH AGREEMENT MAY BE AMENDED, MODIFIED, SUPPLEMENTED, RESTATED OR OTHERWISE CHANGED FROM TIME TO TIME.”

Except as otherwise permitted by this Section 9, each certificate for Common Stock (or Other Securities) issued upon the exercise of any Warrant, and each certificate issued upon the transfer of any such Common Stock (or Other Securities), shall be stamped or otherwise imprinted with a legend in substantially the following form:

“THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS OF ANY STATE, AND MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND APPLICABLE STATE SECURITIES LAWS OR PURSUANT TO AN APPLICABLE EXEMPTION TO THE REGISTRATION REQUIREMENTS OF SUCH ACT AND SUCH LAWS. SUCH SECURITIES MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF EXCEPT IN COMPLIANCE WITH THE CONDITIONS SPECIFIED IN COMMON STOCK PURCHASE WARRANT ISSUED BY ATP OIL & GAS CORPORATION. A COMPLETE AND CORRECT COPY OF THE FORM OF SUCH WARRANT IS AVAILABLE FOR INSPECTION AT THE PRINCIPAL

15

OFFICE OF ATP OIL & GAS CORPORATION. OR AT THE OFFICE OR AGENCY MAINTAINED BY ATP OIL & GAS CORPORATION AS PROVIDED IN SUCH WARRANT AND WILL BE FURNISHED TO THE HOLDER OF SUCH SECURITIES UPON WRITTEN REQUEST AND WITHOUT CHARGE.”

“THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO THE TERMS AND CONDITIONS OF A REGISTRATION RIGHTS AGREEMENT, DATED AS OF FEBRUARY 16, 2004, AS SUCH AGREEMENT MAY BE AMENDED, MODIFIED, SUPPLEMENTED, RESTATED OR OTHERWISE CHANGED FROM TIME TO TIME.”

9.2. Transfer to Comply With the Securities Act. Restricted Securities may not be sold, assigned, pledged, hypothecated, encumbered or in any manner transferred or disposed of, in whole or in part, except in compliance with the provisions of the Securities Act and state securities or Blue Sky laws and the terms and conditions hereof. Other than in connection with any sale, assignment, pledge, hypothecation, encumbrance or any transfer or disposition of this Warrant (or any part thereof) by the Holder to any Related Fund (as defined in the Financing Agreement) or any other affiliate of the Holder, prior to effecting any such sale, assignment, pledge, hypothecation, encumbrance, transfer or disposition, the Holder shall deliver to the Company an opinion of counsel, reasonably satisfactory to the Company, to the effect that such transfer does not require registration under the Securities Act and is otherwise in compliance with the Securities Act and any applicable state securities or Blue Sky laws.

9.3. Termination of Restrictions. The restrictions imposed by this Section 9 on the transferability of Restricted Securities shall cease and terminate as to any particular Restricted Securities (a) when a registration statement with respect to the sale of such securities shall have been declared effective under the Securities Act and such securities shall have been disposed of in accordance with such registration statement, (b) when such securities are sold pursuant to Rule 144 (or any similar provision then in force) under the Securities Act, or (c) when, in the opinion of both counsel for the Holder and counsel for the Company, such restrictions are no longer required or necessary in order to protect the Company against a violation of the Securities Act upon any sale or other disposition of such securities without registration thereunder. Whenever such restrictions shall cease and terminate as to any Restricted Securities, the Holder shall be entitled to receive from the Company, without expense (other than applicable transfer taxes, if any), new securities of like tenor not bearing the applicable legends required by Section 9.1.

10. Reservation of Stock, Etc. The Company shall at all times reserve and keep available, solely for issuance and delivery upon exercise of this Warrant, the number of shares of Common Stock (or Other Securities) from time to time issuable upon exercise of this Warrant. All shares of Common Stock (or Other Securities) issuable upon exercise of this Warrant shall be duly authorized and, when issued upon such exercise, shall be validly issued and, in the case of shares, fully paid and nonassessable with no liability on the part of the holders thereof, and, in the case of all securities, shall be free from all taxes, liens, security interests, encumbrances, preemptive rights and charges. The transfer agent for the Common Stock, which may be the Company (“Transfer Agent”), and every subsequent Transfer Agent for any shares of

16

the Company’s capital stock issuable upon the exercise of any of the purchase rights represented by this Warrant, are hereby irrevocably authorized and directed at all times until the Expiration Date to reserve such number of authorized and unissued shares as shall be requisite for such purpose. The Company shall keep copies of this Warrant on file with the Transfer Agent for the Common Stock and with every subsequent Transfer Agent for any shares of the Company’s capital stock issuable upon the exercise of the rights of purchase represented by this Warrant. The Company shall supply such Transfer Agent with duly executed stock certificates for such purpose. All Warrant Certificates surrendered upon the exercise of the rights thereby evidenced and not required to be returned to the Holder pursuant hereto shall be canceled. Subsequent to the Expiration Date, no shares of Common Stock need be reserved in respect of any unexercised Warrant.

11. Registration and Transfer of Warrant, Etc.

11.1. Warrant Register; Ownership of Warrant. Each Warrant issued by the Company shall be numbered and shall be registered in a warrant register (the “Warrant Register”) as it is issued and transferred, which Warrant Register shall be maintained by the Company at its principal office or, at the Company’s election and expense, by a Warrant Agent or the Company’s transfer agent. The Company shall be entitled to treat the registered Holder of any Warrant on the Warrant Register as the owner in fact thereof for all purposes and shall not be bound to recognize any equitable or other claim to or interest in such Warrant on the part of any other Person, and shall not be affected by any notice to the contrary, except that, if and when any Warrant is properly assigned in blank, the Company may (but shall not be obligated to) treat the bearer thereof as the owner of such Warrant for all purposes. Subject to Section 9, a Warrant, if properly assigned (or assigned by the Holder to any Related Fund (as defined in the Financing Agreement) or any other affiliate of the Holder), may be exercised by a new holder without a new Warrant first having been issued.

11.2. Transfer of Warrant. At any time after May 17, 2004 and subject to compliance with Section 9, if applicable, this Warrant and all rights hereunder are transferable in whole or in part, without charge to the Holder hereof, upon surrender of this Warrant with a properly executed Form of Assignment attached hereto as Exhibit B at the principal office of the Company. Upon any partial transfer, the Company shall at its expense issue and deliver to the Holder a new Warrant of like tenor, in the name of the Holder, which shall be exercisable for a number of shares of Common Stock with respect to which rights under this Warrant were not so transferred. Notwithstanding the first sentence of this Section 11.2 (including, without limitation, the restriction on transferability on or prior to May 17, 2004), at any time after the date hereof and subject to compliance with Section 9, this Warrant (or any part thereof) shall be freely transferable by the Holder to any Related Fund (as defined in the Financing Agreement) or any other affiliate of the Holder.

11.3. Replacement of Warrant. On receipt by the Company of evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this Warrant and, in the case of any such loss, theft or destruction of this Warrant, on delivery of an indemnity bond in such reasonable amount as the Company may determine, or, in the case of any such mutilation, on surrender of such Warrant to the Company at its principal office and

17

cancellation thereof, the Company at its expense shall execute and deliver, in lieu thereof, a new Warrant of like tenor. Applicants for such substitute Warrants shall also comply with such other reasonable regulations and pay such other reasonable charges as the Company may from time to time prescribe by giving notice thereof to the Holder.

11.4. Fractional Shares. Notwithstanding any provision of this Warrant, the Company shall not be required to issue fractions of shares upon exercise of this Warrant or to distribute certificates which evidence fractional shares. In lieu of fractional shares, the Company shall make payment to the Holder, at the time of exercise of this Warrant as herein provided, in an amount in cash equal to such fraction multiplied by the Exercise Price of a share of Common Stock on the date of Warrant exercise.

12. Remedies; Specific Performance. The Company stipulates that there would be no adequate remedy at law to the Holder of this Warrant in the event of any default or threatened default by the Company in the performance of or compliance with any of the terms of this Warrant and accordingly, the Company agrees that, in addition to any other remedy to which the Holder may be entitled at law or in equity, the Holder shall be entitled to seek to compel specific performance of the obligations of the Company under this Warrant, without the posting of any bond, in accordance with the terms and conditions of this Warrant in any court of the United States or any State thereof having jurisdiction, and if any action should be brought in equity to enforce any of the provisions of this Warrant, the Company shall not raise the defense that there is an adequate remedy at law. Except as otherwise provided by law, a delay or omission by the Holder hereto in exercising any right or remedy accruing upon any such breach shall not impair the right or remedy or constitute a waiver of or acquiescence in any such breach. No remedy shall be exclusive of any other remedy. All available remedies shall be cumulative.

13. No Rights or Liabilities as Shareholder. Nothing contained in this Warrant shall be construed as conferring upon the Holder hereof any rights as a shareholder of the Company or as imposing any obligation on the Holder to purchase any securities or as imposing any liabilities on the Holder as a shareholder of the Company, whether such obligation or liabilities are asserted by the Company or by creditors of the Company.

14. Notices. All notices and other communications (and deliveries) provided for or permitted hereunder shall be made in writing by hand delivery, telecopier, any courier guaranteeing overnight delivery or first class registered or certified mail, return receipt requested, postage prepaid, addressed: if to the Company, to the Company at its address at:

ATP Oil & Gas Corporation

4600 Post Oak Place

Suite 200

Houston, Texas 77027

Attention: Chief Financial Officer

Telephone: 713-622-3311

Telecopier: 713-622-5101

18

with a copy to:

ATP Oil & Gas Corporation

4600 Post Oak Place

Suite 200

Houston, Texas 77027

Attention: General Counsel

Telephone: 713-622-3311

Telecopier: 713-622-0289;

if to the Holder, at the address specified in the Financing Agreement; or as to any party, at such other address as shall be designated by such party in a written notice to the other party.

All such notices and communications (and deliveries) shall be deemed to have been duly given: at the time delivered by hand, if personally delivered; when receipt is acknowledged, if telecopied; on the next Business Day, if timely delivered to a courier guaranteeing overnight delivery; and five days after being deposited in the mail, if sent first class or certified mail, return receipt requested, postage prepaid; provided, that the exercise of any Warrant shall be effective in the manner provided in Section 2.

15. Amendments. This Warrant and any term hereof may not be amended, modified, supplemented or terminated, and waivers or consents to departures from the provisions hereof may not be given, except by written instrument duly executed by the party against which enforcement of such amendment, modification, supplement, termination or consent to departure is sought.

16. Descriptive Headings, Etc. The headings in this Warrant are for convenience of reference only and shall not limit or otherwise affect the meaning of terms contained herein. Unless the context of this Warrant otherwise requires: (1) words of any gender shall be deemed to include each other gender; (2) words using the singular or plural number shall also include the plural or singular number, respectively; (3) the words “hereof”, “herein” and “hereunder” and words of similar import when used in this Warrant shall refer to this Warrant as a whole and not to any particular provision of this Warrant, and Section and paragraph references are to the Sections and paragraphs of this Warrant unless otherwise specified; (4) the word “including” and words of similar import when used in this Warrant shall mean “including, without limitation,” unless otherwise specified; (5) “or” is not exclusive; and (6) provisions apply to successive events and transactions.

17. Governing Law. This Warrant shall be governed by, and construed in accordance with, the laws of the State of New York (without giving effect to the conflict of laws principles thereof, except Sections 5-1401 and 5-1402 of the New York General Obligations Law).

18. Judicial Proceedings. (a) Each of the parties hereto hereby irrevocably and unconditionally submits, for itself and its property, to the nonexclusive jurisdiction of any New York State court or federal court of the United States of America sitting in New York City, and any appellate court from any thereof, in any action or proceeding arising out of or relating to this Warrant, or for recognition or enforcement of any judgment, and each of the parties hereto

19

hereby irrevocably and unconditionally agrees that all claims in respect of any such action or proceeding may be heard and determined in any such New York State court or, to the extent permitted by law, in such federal court. Each of the parties hereto agrees that a final judgment in any such action or proceeding shall be conclusive and may be enforced in other jurisdictions by suit on the judgment or in any other manner provided by law. Nothing in this Agreement shall affect any right that any party may otherwise have to bring any action or proceeding relating to this Warrant in the courts of any jurisdiction.

(b) Each of the parties hereto irrevocably and unconditionally waives, to the fullest extent it may legally and effectively do so, any objection that it may now or hereafter have to the laying of venue of any suit, action or proceeding arising out of or relating to this Warrant in any New York State or federal court. Each of the parties hereto hereby irrevocably waives, to the fullest extent permitted by law, the defense of an inconvenient forum to the maintenance of such action or proceeding in any such court.

19. Waiver of Jury Trial. TO THE MAXIMUM EXTENT PERMITTED BY LAW, THE COMPANY AND THE HOLDER HEREBY IRREVOCABLY WAIVE TRIAL BY JURY IN ANY ACTION, SUIT OR PROCEEDING, WHETHER AT LAW OR EQUITY, BROUGHT BY IT OR THE HOLDER IN CONNECTION WITH THIS WARRANT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

20. Registration Rights Agreement. The shares of Common Stock (and Other Securities) issuable upon exercise of this Warrant (or upon conversion of any shares of Common Stock issued upon such exercise) shall constitute Registrable Securities (as such term is defined in the Registration Rights Agreement). Each Holder of this Warrant shall be entitled to all of the benefits afforded to a holder of any such Registrable Securities under the Registration Rights Agreement and such Holder, by its acceptance of this Warrant, agrees to be bound by and to comply with the terms and conditions of the Registration Rights Agreement applicable to such Holder as a holder of such Registrable Securities.

21. Call Rights. On or prior to May 17, 2004, and subject to the provisions of this Section 21, the Company shall have the right to purchase all (but not less than all) of this Warrant from the Holder. The Company may exercise its call right by providing written notice to the Holder (the “Call Notice”). Any exercise by the Company of its call right shall be irrevocable. The closing of the purchase by the Company, and the sale by the Holder, of this Warrant, following exercise by the Company of its call right (the “Call Closing”) shall be held at the principal office of Holder or its legal counsel on the second (2nd) business day following Holder’s receipt of the Company’s Call Notice; provided, however, that such date may not be later than May 17, 2004. At the Call Closing, Holder shall deliver this Warrant to the Company against receipt from the Company of the aggregate Call Price (as defined below) therefor in cash by wire transfer of immediately available funds to Holder’s designated account. As used herein: “Call Price” shall mean $112,500. If Holder tenders this Warrant at the Call Closing and the Company fails to tender payment of the required aggregate Call Price at the Call Closing, then the Company’s call right shall thereupon terminate and be of no force or effect, notwithstanding its previous exercise thereof, and the Company shall indemnify Holder against all costs, expenses (including without limitation reasonable attorneys’ fees), losses and damages paid, suffered or

20

incurred by Holder as a result of the Company’s exercise of such call right and failure to tender such aggregate Call Price.

23. Costs and Attorneys’ Fees. In the event that any action, suit or other proceeding is instituted concerning or arising out of this Warrant, the Corporation agrees and the Holder, by taking and holding this Warrant agrees, that the prevailing party shall recover from the non-prevailing party all of such prevailing party’s costs and reasonable attorneys’ fees incurred in each and every such action, suit or other proceeding, including any and all appeals or petitions therefrom.

24. Most Favorable Holder. The Company agrees that if at any time or from time to time prior to the Expiration Date it enters into any agreement with, or issues Options or Convertible Securities to, any Person other than a Holder of this Warrant, which provides such Person with more favorable terms of the type set forth in Sections 3, 4, 5 and 6 of this Warrant, then the Company shall issue to the Holder a new Warrant in exchange for this Warrant, which shall contain such terms, effective from the date such agreement is consummated or Option or Convertible Security is issued until the Expiration Date.

21

IN WITNESS WHEREOF, the Company has executed and delivered this Warrant to the Holder as of the date first above written.

ATP OIL & GAS CORPORATION
By:	/s/ T. Paul Bulmahn
Name:
Title:	President

[Signature Page to Warrant W-1 of ATP Oil & Gas Corporation]

22

EXHIBIT A to

Common Stock Purchase Warrant

FORM OF

ELECTION TO PURCHASE SHARES

The undersigned hereby irrevocably elects to exercise the Warrant to purchase              shares of Common Stock, par value $.001 per share (“Common Stock”), of ATP OIL & GAS CORPORATION and hereby makes payment of $             therefor in accordance with the terms of the Common Stock Purchase Warrant against delivery of stock certificates representing such shares. The undersigned hereby requests that certificates for such shares be issued and delivered as follows:

ISSUE TO:

(NAME)

(ADDRESS, INCLUDING ZIP CODE)

(SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER)

DELIVER TO:
	(NAME)
	(ADDRESS, INCLUDING ZIP CODE)

If the number of shares of Common Stock purchased (and/or reduced) hereby is less than the total number of Shares then covered by the Warrant, the undersigned requests that this Warrant, which shall note the number of shares of Common Stock issued to date, be delivered to the holder as follows:

ISSUE TO:

	(NAME OF HOLDER)
	(ADDRESS, INCLUDING ZIP CODE)
DELIVER TO:

(NAME OF HOLDER)

(ADDRESS, INCLUDING ZIP CODE)

Dated:                     , 200_

NAME OF HOLDER¹

By

Name:

Title:

¹ Name of Holder must conform in all respects to name of holder as specified on the face of the Warrant.

EXHIBIT B to

Common Stock Purchase Warrant

FORM OF ASSIGNMENT

FOR VALUE RECEIVED, the undersigned hereby sells, assigns, and transfers unto the Assignee named below all of the rights of the undersigned to purchase Common Stock, par value $.001 per share (“Common Stock”), of ATP OIL & GAS CORPORATION represented by the Warrant, with respect to the number of shares of Common Stock set forth below:

Name of Assignee Address Number of Shares

and does hereby irrevocably constitute and appoint              Attorney to make such transfer on the books of ATP OIL & GAS CORPORATION maintained for that purpose, with full power of substitution in the premises.

Dated:                     , 200_ NAME OF HOLDER¹

By

Name:

Title:

¹ Name of Holder must conform in all respects to name of holder as specified on the face of the Warrant.

EX-10.1

Exhibit 10.1

AMENDMENT NO. 2

TO THE

SECOND AMENDED AND RESTATED

FINANCING AGREEMENT

THIS AMENDMENT NO. 2, dated as of December 3, 2003 (this “Amendment”), to the Second Amended and Restated Financing Agreement, dated as of August 13, 2003, as amended or otherwise modified from time to time (the “Financing Agreement”), by and among ATP Oil & Gas Corporation, a Texas corporation (the ”Borrower”), each subsidiary of the Borrower listed as a “Guarantor” on the signature pages thereto (each a “Guarantor” and collectively, the “Guarantors” and, together with the Borrower, each a “Loan Party” and collectively, the “Loan Parties”), each of the lenders from time to time party thereto (each a “Lender” and collectively, the ”Lenders”), Ableco Finance LLC, a Delaware limited liability company (“Ableco”), as collateral agent and administrative agent for the Lenders (in such capacity, the ”Collateral Agent” or the “Administrative Agent”), and Wells Fargo Foothill, Inc., a California corporation (“Foothill”), as funding agent for the Lenders (in such capacity, the “Funding Agent”, and together with the Administrative Agent and the Collateral Agent, each an “Agent” and collectively the “Agents”).

W I T N E S S E T H:

WHEREAS, pursuant to the Financing Agreement, among the Borrower, the Guarantors and each of the Lenders from time to time party thereto, Ableco, in its capacity as the Collateral Agent and Administrative Agent for the Lenders, and Foothill, in its capacity as Funding Agent for the Lenders, the Lenders have agreed to make certain revolving loans, which includes a subfacility for the issuance of Letters of Credit (as defined in the Financing Agreement) to the Borrower; and

WHEREAS, the Borrower has requested that Ableco and its Affiliate assignees, and Ableco and its Affiliate assignees have agreed to provide an additional revolving D credit commitment in an aggregate principal amount not to exceed $15,000,000, the proceeds of which will be used to fund expenditures related to the Oil and Gas Properties (as defined in the Financing Agreement) of ATP Oil & Gas (UK) Limited, a wholly owned subsidiary of the Borrower (“ATP UK”), located in the United Kingdom sector of the North Sea (the “UK Oil and Gas Properties”), to fund general working capital of the Borrower and the Foreign Subsidiaries and to pay fees and expenses related to this Amendment and the other Loan Documents.

NOW, THEREFORE, in consideration of the premises and agreements herein, the parties hereto hereby agree as follows:

1. Definitions. All terms used herein that are defined in the Financing Agreement and not otherwise defined herein are used herein as defined therein.

2. Recitals. Clause (ii) of the second WHEREAS paragraph set forth in the Recitals is hereby amended by deleting in its entirety the phrase “three revolving credit facilities” and substituting in lieu thereof the phrase “four revolving credit facilities”.

3. Changes to Definitions. Each of the following definitions set forth in Section 1.01 of the Financing Agreement is hereby amended, restated, modified, supplemented, deleted or added:

(a) The second proviso of the definition of the term “Borrowing Base” contained in Section 1.01 of the Financing Agreement is hereby amended by deleting the date “February 28, 2004” and substituting in lieu thereof the date “February 16, 2004”.

(b) The definition of the term “Commitments” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Commitments’ means, with respect to each Lender, such Lender’s Revolving A Credit Commitment, Revolving B Credit Commitment, Revolving C Credit Commitment and Revolving D Credit Commitment.”

(c) The definition of the term “Final Maturity Date” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Final Maturity Date’ means (i) with respect to the Total Revolving A Credit Commitment, the Total Revolving B Credit Commitment and the Total Revolving C Credit Commitment, August 1, 2007, and (ii) with respect to the Total Revolving D Credit Commitment, February 16, 2004, or, in either case of clause (i) or (ii) above, such earlier date on which the applicable Loans shall become due and payable in accordance with the terms of this Agreement and the other Loan Documents.”

(d) The definition of the term “EBITDA Deficit” contained in Section 1.01 of the Financing Agreement is hereby deleted in its entirety.

(e) The definition of the term “Foreign Subsidiaries” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Foreign Subsidiaries’ means each of ATP Netherlands and any other subsidiary of the borrower or any other Foreign Subsidiary organized under the laws of a country other than the United States to the extent the formation or acquisition of such Subsidiary is in compliance with the terms and provisions of the Loan Documents, but shall not include ATP UK or any of its Subsidiaries.”

-2-

(f) The definition of the term “Guaranty” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Guaranty’ means each guaranty, substantially in the form of Exhibit A or such other guaranty the terms and conditions of which are satisfactory to the Agents, including, without limitation, each guaranty which may be entered into in compliance with the laws of England and Wales, the Netherlands or any other foreign jurisdiction.”

(g) The definition of the term “Pledge Agreement” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Pledge Agreement’ means a Pledge and Security Agreement made by a Loan Party in favor of the Collateral Agent for the benefit of the Lenders, substantially in the form of Exhibit C or such other form the terms and conditions of which are satisfactory to the Agents, including, without limitation, each pledge agreement, deed of pledge, share charge or other document or instrument (including, without limitation, the Dutch Security Agreements) entered into in compliance with the laws of the England and Wales, the Netherlands or any other foreign jurisdiction, in each case, securing the Obligations and delivered to the Collateral Agent.”

(h) The definition of the term “Petroleum Engineers” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Petroleum Engineers’ means (a) in the case of Oil and Gas Properties within the jurisdiction of the United States, Ryder Scott Company, L.P. and (b) in the case of Oil and Gas Properties within the jurisdiction of the United Kingdom, Troy-Ikoda Limited or, in either case, such other petroleum engineers of recognized national standing in the applicable country as may be selected by the Borrower with the prior consent of the Agents.”

(i) The definition of the term “Pro Rata Share” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Pro Rata Share’ means:

(a) with respect to a Lender’s obligation to make Revolving A Loans and receive payments of interest, fees, and principal with respect thereto, the percentage obtained by dividing (i) such Lender’s Revolving A Credit Commitment, by (ii) the Total Revolving A Credit Commitment, provided, that, if the Total Revolving A Credit Commitment has been reduced to zero, the

-3-

numerator shall be the aggregate unpaid principal amount of such Lender’s Revolving A Loans (including an amount equal to such Revolving A Loan Lender’s Pro Rata Share (as determined by clause (e) hereof) of the Agent Advances) and its interest in the Letter of Credit Obligations and the denominator shall be the aggregate unpaid principal amount of all Revolving A Loans (including an aggregate amount equal to the Revolving A Lenders’ Pro Rata Share (as determined by clause (e) hereof) of the Agent Advances) and Letter of Credit Obligations,

(b) with respect to a Lender’s obligation to make Revolving B Loans and receive payments of interest, fees, and principal with respect thereto, the percentage obtained by dividing (i) such Lender’s Revolving B Credit Commitment, by (ii) the Total Revolving B Credit Commitment, provided, that, if the Total Revolving B Credit Commitment has been reduced to zero, the numerator shall be the aggregate unpaid principal amount of such Lender’s Revolving B Loans (including an amount equal to such Revolving B Loan Lender’s Pro Rata Share (as determined by clause (e) hereof) of the Agent Advances) and the denominator shall be the aggregate unpaid principal amount of all Revolving B Loans (including an aggregate amount equal to the Revolving B Lenders’ Pro Rata Share (as determined by clause (e) hereof) of the Agent Advances),

(c) with respect to a Lender’s obligation to make Revolving C Loans and receive payments of interest, fees, and principal with respect thereto, the percentage obtained by dividing (i) such Lender’s Revolving C Credit Commitment, by (ii) the Total Revolving C Credit Commitment, provided, that, if the Total Revolving C Credit Commitment has been reduced to zero, the numerator shall be the aggregate unpaid principal amount of such Lender’s Revolving C Loans (including an amount equal to such Revolving C Loan Lender’s Pro Rata Share (as determined by clause (e) hereof) of the Agent Advances) and the denominator shall be the aggregate unpaid principal amount of all Revolving C Loans (including an aggregate amount equal to the Revolving C Lenders’ Pro Rata Share (as determined by clause (e) hereof) of the Agent Advances),

(d) with respect to a Lender’s obligation to make Revolving D Loans and receive payments of interest, fees, and principal with respect thereto, the percentage obtained by dividing (i) such Lender’s Revolving D Credit Commitment, by (ii) the Total Revolving D Credit Commitment, provided, that, if the Total Revolving D Credit Commitment has been reduced to zero, the numerator shall be the aggregate unpaid principal amount of such Lender’s Revolving D Loans (including an amount equal to such Revolving D Loan Lender’s Pro Rata Share (as determined by clause (e) hereof) of the Agent Advances) and the denominator shall be the aggregate unpaid principal amount of

-4-

all Revolving D Loans (including an aggregate amount equal to the Revolving D Lenders’ Pro Rata Share (as determined by clause (e) hereof) of the Agent Advances), and

(e) with respect to all other matters (including, without limitation, the indemnification obligations arising under Section 10.05), the percentage obtained by dividing (i) the sum of such Lender’s Revolving A Credit Commitment, Revolving B Credit Commitment, Revolving C Credit Commitment and Revolving D Credit Commitment, by (ii) the sum of the Total Revolving Credit Commitment, provided, that, if such Lender’s Revolving A Credit Commitment, Revolving B Credit Commitment, Revolving C Credit Commitment or Revolving D Credit Commitment shall have been reduced to zero, such Lender’s Revolving A Credit Commitment, Revolving B Credit Commitment, Revolving C Credit Commitment or Revolving D Credit Commitment, as the case may be, shall be deemed to be the aggregate unpaid principal amount of such Lender’s Revolving A Loans, Revolving B Loans, Revolving C Loans or Revolving D Loans, as the case may be (including Agent Advances), and its interest in the Letter of Credit Obligations and if the Total Revolving A Credit Commitment, Total Revolving B Credit Commitment, Total Revolving C Credit Commitment or Total Revolving D Credit Commitment shall have been reduced to zero, the Total Revolving A Credit Commitment, Total Revolving B Credit Commitment, Total Revolving C Credit Commitment or Total Revolving D Credit Commitment, as the case may be, shall be deemed to be the aggregate unpaid principal amount of all Revolving A Loans, Revolving B Loans, Revolving C Loans and Revolving D Loans (including Agent Advances) and Letter of Credit Obligations.”

(j) The definition of the term “Required Lenders” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Required Lenders’ means at any time, Lenders whose Pro Rata Shares aggregate at least 51% as determined pursuant to clause (e) of the definition of “Pro Rata Share”; provided, that (a) so long as Foothill and its Affiliates hold not less than 30% of the aggregate principal amount of the Revolving A Credit Commitment, or if the Revolving A Credit Commitment has been terminated or reduced to zero, the Revolving A Loans, “Required Lenders” shall include Foothill, and (b) so long as Ableco and its Affiliates or Related Funds hold not less than 30% of the aggregate principal amount of the Revolving B Credit Commitment, the Revolving C Credit Commitment and the Revolving D Credit Commitment, or if any of the Revolving B Credit Commitment, the Revolving C Credit Commitment or the Revolving D Credit Commitment has been terminated or reduced to zero, the Revolving B Loans, the Revolving C Loans or the Revolving D Loans, as applicable, “Required Lenders” shall include Ableco.”

-5-

(k) The definition of the term “Revolving C Loan Lender” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Revolving C Loan Lender’ means a Lender with a Revolving C Credit Commitment.”

(l) The definition of the term “Revolving Loan Commitment” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Revolving Loan Commitment’ means, with respect to each Lender, such Lender’s Revolving A Loan Commitment, Revolving B Loan Commitment, Revolving C Loan Commitment and Revolving D Loan Commitment.”

(m) The definition of the term “Revolving Loan Lender” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Revolving Loan Lender’ means, collectively, the Revolving A Loan Lenders, Revolving B Loan Lenders, Revolving C Loan Lenders and Revolving D Loan Lenders.”

(n) The definition of the term “Revolving Loans “ contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Revolving Loans’ means, collectively, the Revolving A Loans, Revolving B Loans, Revolving C Loans and Revolving D Loans.”

(o) The definition of the term “Security Agreement” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Security Agreement’ means a Security Agreement made by a Loan Party in favor of the Collateral Agent for the benefit of the Lenders, substantially in the form of Exhibit B or such other form the terms and conditions of which are satisfactory to the Agents, including, without limitation, each security agreement, instrument or other document entered into in compliance with the laws of England and Wales, the Netherlands or any other foreign jurisdiction, in each case, securing the Obligations and delivered to the Collateral Agent.”

(p) The definition of the term “Specified Event of Default” contained in Section 1.01 of the Financing Agreement is hereby deleted in its entirety.

-6-

(q) The definition of the term “Total Revolving Credit Commitment” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“‘Total Revolving Credit Commitment’ means the sum of the Total Revolving A Credit Commitment, the Total Revolving B Credit Commitment, the Total Revolving C Credit Commitment and the Total Revolving D Credit Commitment.”

(r) Each of the following definitions of the terms is hereby added to Section 1.01 of the Financing Agreement in the appropriate alphabetical order:

“ ‘IPE’ means the International Petroleum Exchange or its successor entity.”

“ ‘IPE Strip Price’ means the lower of (i) as of any date of determination (A) for the 24 month period commencing with the month in which the date of determination occurs, the average of the 24 succeeding monthly futures contract prices, commencing with the month during which the determination date occurs, for each of the appropriate crude oil and natural gas categories included in the most recent UK Reserve Report provided by the Borrower to the Agents pursuant to Section 7.01(a)(xxv), as quoted on the IPE, and (B) for periods after such 24 month period, the average of the quoted prices for the period from and including the 13^th month in such 24 month period through the 24^th month in such period; provided, that if the IPE no longer provides futures contract price quotes or has ceased to operate, the comparable futures contract prices quoted on such other nationally recognized commodities exchange as the Agents shall designate.”

“ ‘Material Adverse Deviation’ means any of the following deviations from any of the following line items set forth in the Weekly Cash Flow Schedules:

(i) at the end of each week, for the period including the period of the week ending December 5, 2003 through the end of the applicable weekly period, the aggregate amount of actual Collections from the sale of Hydrocarbons of the Loan Parties for such period is less than 90% of the aggregate amount of Collections from the sale of Hydrocarbons of the Loan Parties on the line items entitled “Cash Inflows/Revenue Receipts” set forth in the Weekly Cash Flow Schedules for such period; provided, that, for purposes of such calculation, the Borrower may include any Collections received by it on or prior to the date on which the Borrower is required to deliver its weekly report pursuant to Section 7.01(a)(xxvii),

(ii) at the end of each week, for the period including the period of the week ending December 5, 2003 through the end of the applicable weekly period, the aggregate amount of actual loans, capital contributions or other

-7-

distributions from the Borrower to ATP UK is greater than 110% of the aggregate amount of such loans, capital contributions or other distributions from the Borrower to ATP UK on the line items entitled “UK Disbursements – Other” and “UK Disbursements — Helvellyn” set forth in the Weekly Cash Flow Schedules for such period, or

(iii) at the end of each week, for the period including the period of the week ending December 5, 2003 through the end of the applicable weekly period, the aggregate amount of actual disbursements by ATP UK to develop its Oil and Gas Properties at Helvellyn is greater than 110% of the aggregate amount of such disbursements by ATP UK on the line item entitled “UK Disbursements – Helvellyn” set forth in the Weekly Cash Flow Schedules for such period.”

“ ‘UK PV-10’ means, as of any date of determination, the sum of the present values of the amounts of net revenues before income taxes expected to be received in each of the months following the date of determination on the basis of estimated production from Proved Reserves during such months determined as follows:

(a) each such monthly net revenue amount shall be calculated (x) on the basis of the applicable IPE Strip Price for the appropriate category of oil or gas as of such date of determination, adjusting such price to reflect (A) the difference between the appropriate IPE futures contract prices and the sales prices at the delivery point where the gas or oil, as the case may be, produced by the applicable Oil and Gas Property, is sold with respect to Hydrocarbons produced from specific Oil and Gas Properties of ATP UK, (B) the prices for fixed price contracts for such month, (C) the prices for hedged volumes for such month and (D) Btu content, (y) assuming that production costs remain constant throughout the periods of the calculation of such monthly net revenues, and (z) otherwise applying the financial accounting and reporting standards prescribed by the SEC for application of the successful efforts method of accounting for such revenues under Rule 4-10 of Regulation S-X as promulgated by the SEC from time to time except for pricing parameters which are addressed in clause (x) above; and

(b) the present value of each such monthly net revenue amount shall be determined by discounting each such monthly net revenue amount from the month in which it is expected to be received, on a monthly basis, to such date of determination at a rate of 10% per annum.”

“ ‘Revolving D Credit Commitment’ means, with respect to each Lender, the commitment of such Lender to make Revolving D Loans to the Borrower in the amount set forth opposite such Lender’s name in Schedule 1.01(A) hereto, as such amount may be terminated or reduced from time to time in accordance with the terms of the Financing Agreement.”

-8-

“ ‘Revolving D Loan’ means a loan made by a Lender to the Borrower pursuant to Section 2.01(a)(iv).”

“ ‘Revolving D Loan Lender’ means a Lender with a Revolving D Credit Commitment.”

“ ‘Total Revolving D Credit Commitment’ means the sum of the amounts of the Lenders’ Revolving D Credit Commitments.”

“ ‘UK Reserve Report’ has the meaning specified therefor in Section 7.01(a)(xxv).”

“ ‘Weekly Cash Flow Schedules’ has the meaning specified therefor in Section 7.01(a)(xiv).”

4. Commitments. (a) Section 2.01(a) of the Financing Agreement is hereby amended by inserting immediately after clause (iii) the following new clause (iv):

“(iv) each Revolving D Loan Lender severally agrees to make Revolving D Loans to the Borrower at any time and from time to time from December 3, 2003 to the Final Maturity Date, or until the earlier reduction of its Revolving D Credit Commitment to zero in accordance with the terms hereof, in an aggregate principal amount of Revolving D Loans at any time outstanding not to exceed the amount of such Lender’s Revolving D Credit Commitment.”

(b) Section 2.01(b) of the Financing Agreement is hereby amended by inserting immediately after clause (iii) the following new clause (iv):

“(iv) The aggregate principal amount of Revolving D Loans outstanding at any time to the Borrower shall not exceed the lesser of the Total Revolving D Credit Commitment and 110% of the principal amount of outstanding loans and other disbursements set forth in the Foreign Working Capital Budget for the applicable week.”

(c) Before giving effect to the amendment set forth in clause (b) above, existing clause (viii) of Section 2.01(b) of the Financing Agreement is hereby deleted in its entirety.

(d) Before giving effect to the amendment set forth in clause (b) above, the following clauses of Section 2.01(b) of the Financing Agreement shall be renumbered as follows: clause (iv) shall be renumbered clause (v), clause (v) shall be renumbered clause (vi), clause (vi) shall be renumbered clause (vii), and clause (vii) shall be renumbered clause (viii).

-9-

5. Making the Loans. (a) Clause (iii) of Section 2.02(a) of the Financing Agreement is hereby amended by (i) deleting the word “or” between the phrases “a Revolving B Loan” and “a Revolving C Loan” and inserting in lieu thereof a comma, and (ii) inserting immediately prior to the comma at the end of such clause the phrase “or a Revolving D Loan”.

(b) Section 2.02(b) of the Financing Agreement is hereby amended by inserting immediately prior to the period at the end of such Section, the following proviso:

“; provided, that, if Foothill is the Funding Agent, any Revolving Loan may be made in a minimum amount of $100,000 and in an integral multiple of $100,000”

(c) Section 2.02(c) of the Financing Agreement is hereby amended by (i) deleting the word “and” between the phrases “the Total Revolving B Credit Commitment” and “the Total Revolving C Credit Commitment” and inserting in lieu thereof a comma, and (ii) inserting immediately prior to the comma after the phrase “the Total Revolving C Credit Commitment”, the phrase “and the Total Revolving D Credit Commitment”.

6. Repayment of Loans; Evidence of Debt . Section 2.03(a) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(a) The outstanding principal of the Revolving Loans shall be due and payable on the applicable Final Maturity Date; provided, however, that, if on February 16, 2004, the Total Revolving C Credit Commitment is terminated pursuant to Section 2.05(a), (x) the aggregate outstanding principal of the Revolving C Loans shall be repayable in monthly installments, on the last day of each month, commencing on February 29, 2004 until paid in full, in an amount equal to $400,000 per month, with the last such installment to be in the amount necessary to repay in full the unpaid principal amount of the remaining aggregate outstanding amount of the Revolving C Loans, and (y) the aggregate outstanding principal of the Foreign Loans shall be repayable in monthly installments, on the last day of each month, commencing on February 29, 2004, until paid in full, in an amount equal to $500,000 per month, with the last such installment to be in the amount necessary to repay in full the unpaid principal amount of the remaining aggregate outstanding amount of the Foreign Loans.”

7. Interest. (a) The proviso of clause (ii) of Section 2.04(a) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“provided, that, so long as no Event of Default has occurred and is continuing, a portion of the interest on the Revolving B Loans equal to 1.0% per annum that has accrued during such period shall be capitalized on each interest payment date and added to the outstanding principal amount of the Revolving B Loans and the interest otherwise payable in cash shall be reduced by the amount of interest so capitalized, but such interest may, at the option of the Borrower after notice to the Agents, be paid in cash by the Borrower.”

-10-

(b) The first and second provisos of clause (iii) of Section 2.04(a) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“provided, that, if on February 16, 2004, the then applicable Borrowing Base is equal to or greater than $110,000,000 and there exists no Event of Default, interest on each Revolving C Loan shall be at a rate per annum equal to the greater of (i) the Reference Rate plus 7.0% and (ii) 11.25%; provided, further, that so long as no Event of Default has occurred and is continuing, a portion of the interest on the Revolving C Loans equal to 2.0% per annum that has accrued during such period shall be capitalized on each interest payment date and added to the outstanding principal amount of the Revolving C Loans and the interest otherwise payable in cash shall be reduced by the amount of interest so capitalized, but such interest may, at the option of the Borrower after notice to the Agents, be paid in cash by the Borrower.”

(c) Section 2.04(a) of the Financing Agreement is hereby amended by inserting immediately after clause (iii) the following new clause (iv):

“(iv) Each Revolving D Loan shall bear interest on the principal amount thereof from time to time outstanding, from the date of such Revolving D Loan until such principal amount becomes due, at a rate per annum equal to 15.0%; provided, that, so long as no Event of Default has occurred and is continuing, a portion of the interest on the Revolving D Loans equal to 5.0% per annum that has accrued during such period shall be capitalized on each interest payment date and added to the outstanding principal amount of the Revolving D Loans and the interest otherwise payable in cash shall be reduced by the amount of interest so capitalized, but such interest may, at the option of the Borrower after notice to the Agents, be paid in cash by the Borrower. For purposes of this Agreement and the other Loan Documents, the amounts so capitalized hereunder shall bear interest in accordance with this Section 2.04 as though such amounts constituted a Revolving D Loan made by the Revolving D Loan Lenders to the Borrower.”

8. Reduction of Commitments. Section 2.05(a) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(i) Each of the Total Revolving A Credit Commitment, the Total Revolving B Credit Commitment, the Total Revolving C Credit Commitment and the Total Revolving D Credit Commitment shall terminate on the applicable Final Maturity Date; provided, however, that, if on February 16, 2004, the then applicable Borrowing Base is less than $110,000,000, the Total Revolving C Credit Commitment shall terminate. Notwithstanding anything contained in this Agreement or the other Loan Documents, unless all of the Revolving D Lenders otherwise agree, each prepayment (whether pursuant to an optional, scheduled or

-11-

mandatory prepayment) of the Revolving D Loans shall result in a permanent reduction in the Total Revolving D Credit Commitment in an amount equal to the amount of such prepayment.

(ii) The Borrower may, without premium or penalty, reduce (w) the Total Revolving A Credit Commitment to an amount (which may be zero) not less than the sum of (A) the aggregate unpaid principal amount of all Revolving A Loans then outstanding, (B) the aggregate principal amount of all Revolving A Loans not yet made as to which a Notice of Borrowing has been given by the Borrower under Section 2.02, (C) the Letter of Credit Obligations at such time and (D) the stated amount of all Letters of Credit not yet issued as to which a request has been made and not withdrawn; (x) the Total Revolving B Credit Commitment to an amount (which may be zero) not less than the sum of (A) the aggregate unpaid principal amount of all Revolving B Loans then outstanding, (B) the aggregate principal amount of all Revolving B Loans not yet made as to which a Notice of Borrowing has been given by the Borrower under Section 2.02 and (C) the aggregate principal amount of Revolving B Loans not yet made but which will be made pursuant to Section 2.05(c)(ii) upon the opening or establishment of a Letter of Credit pursuant to Section 3.03(a); (y) the Total Revolving C Credit Commitment to an amount (which may be zero) not less than the sum of (A) the aggregate unpaid principal amount of all Revolving C Loans then outstanding, (B) the aggregate principal amount of all Revolving C Loans not yet made as to which a Notice of Borrowing has been given by the Borrower under Section 2.02 and (C) the aggregate principal amount of Revolving C Loans not yet made but which will be made pursuant to Section 2.05(c)(ii) upon the opening or establishment of a Letter of Credit pursuant to Section 3.03(a); and (z) the Total Revolving D Credit Commitment to an amount (which may be zero) not less than the sum of (A) the aggregate unpaid principal amount of all Revolving D Loans then outstanding and (B) the aggregate principal amount of all Revolving D Loans not yet made as to which a Notice of Borrowing has been given by the Borrower under Section 2.02. Each such reduction shall be in an amount which is an integral multiple of $1,000,000 (unless the applicable Total Revolving Credit Commitment in effect immediately prior to such reduction is less than $1,000,000), shall be made by providing not less than five (5) Business Days’ prior written notice to the Agents and shall be irrevocable.

(iii) Once reduced, the Total Revolving A Credit Commitment, the Total Revolving B Credit Commitment, the Total Revolving C Credit Commitment and the Total Revolving D Credit Commitment may not be increased. Each such reduction of the Total Revolving A Credit Commitment, the Total Revolving B Credit Commitment, the Total Revolving C Credit Commitment or the Total Revolving D Credit Commitment shall reduce the Revolving A Credit Commitment, the Revolving B Credit Commitment, the Revolving C Credit Commitment or the Revolving D Credit Commitment, as the

-12-

case may be, of each Lender proportionately in accordance with its Pro Rata Share thereof.”

9. Mandatory Prepayments. (a) Clause (viii) of Section 2.05(c) of the Financing Agreement is hereby deleted in its entirety.

(b) Immediately after giving effect to clause (a) above, clause (xi) of Section 2.05(c) of the Financing Agreement shall be renumbered clause (viii).

10. Application of Payments. Section 2.05(d) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“In the absence of an Event of Default, the prepayments required under Section 2.05(c)(i), (c)(iii), (c)(iv), (c)(v), (c)(vi), (c)(vii) and (c)(viii) shall be applied as follows:

(i) the proceeds from any prepayment pursuant to any Disposition of Collateral of ATP UK, any incurrence by ATP UK of any Indebtedness, any Extraordinary Receipts of ATP UK, the repayment of any Foreign Loans made to ATP UK or any Collections of ATP UK shall be applied as follows: first, ratably to the Revolving D Loans until paid in full, second, ratably to the Revolving C Loans until paid in full, third, ratably to the Revolving B Loans until paid in full, and, fourth, ratably to the Revolving A Loans and Letter of Credit Obligations (or, to the extent such Letter of Credit Obligations are contingent, to provide cash collateral in an amount equal to 110% of such Letter of Credit Obligations) until paid in full; and

(ii) the proceeds from any prepayment pursuant to any Disposition of any Capital Stock of ATP UK or any issuance by ATP UK of any shares of its Capital Stock shall be applied as follows: (x) 65% of the proceeds of such Disposition or issuance shall be applied first, ratably to the Revolving C Loans until paid in full, second, ratably to the Revolving B Loans until paid in full, third, ratably to the Revolving A Loans and Letter of Credit Obligations (or, to the extent such Letter of Credit Obligations are contingent, to provide cash collateral in an amount equal to 110% of such Letter of Credit Obligations) until paid in full, and, fourth, ratably to the Revolving D Loans until paid in full, and (y) the remaining proceeds shall be applied first, ratably to the Revolving D Loans until paid in full, second, ratably to the Revolving C Loans until paid in full, third, ratably to the Revolving B Loans until paid in full, and, fourth, ratably to the Revolving A Loans and Letter of Credit Obligations (or, to the extent such Letter of Credit Obligations are contingent, to provide cash collateral in an amount equal to 110% of such Letter of Credit Obligations) until paid in full; and

(iii) the proceeds of any other prepayment pursuant to Sections 2.05(c)(i) (other than funds to cash collateralize the Letter of Credit Obligations

-13-

or to prepay the Revolving A Loans as a result of the Revolving A Loans exceeding 100% of the amount attributable to clause (i) of the definition of “Borrowing Base”), (c)(iii) (other than Collections of ATP UK, Collections related to specific items of Collateral identified in clause (i) or (ii) of this Section 2.05(d)), (c)(iv) (other than Dispositions of Collateral of ATP UK and of shares of Capital Stock of ATP UK), (c)(v) (other than the issuance by ATP UK of any shares of its Capital Stock or the incurrence by ATP UK of any Indebtedness), (c)(vi) (other than any Extraordinary Receipts of ATP UK), (c)(vii) and (c)(viii) (other than repayments of Foreign Loans made to ATP UK) shall be applied as follows: first, ratably to the Revolving C Loans until paid in full, second, ratably to the Revolving B Loans until paid in full, third, ratably to the Revolving A Loans and Letter of Credit Obligations (or, to the extent such Letter of Credit Obligations are contingent, to provide cash collateral in an amount equal to 110% of such Letter of Credit Obligations) until paid in full, and, fourth, ratably to the Revolving D Loans until paid in full.”

11. Apportionment of Payments. (a) Section 4.04(b) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“Subject to Section 4.04(e) and the other provisions of this Agreement, after the occurrence and during the continuance of an Event of Default, the Funding Agent may, and upon the direction of the Required Lenders or the Required Revolving A Lenders shall, apply all payments in respect of any Obligations and all proceeds of the Collateral: (i) first, ratably to pay the Obligations in respect of any fees (including any fees or charges assessed by the L/C Issuer), expense reimbursements, indemnities and other amounts then due to the Agents or the L/C Issuer until paid in full; (ii) second, ratably to pay the Revolving A Loans in respect of any fees (including Letter of Credit Fees), expense reimbursements and indemnities then due to the Revolving A Loan Lenders until paid in full; (iii) third, ratably to pay interest due in respect of the Agent Advances until paid in full; (iv) fourth, ratably to pay principal of the Agent Advances until paid in full; (v) fifth, ratably to pay interest due in respect of the Revolving A Loans and Letter of Credit Obligations until paid in full; (vi) sixth, ratably to pay principal of the Revolving A Loans and Letter of Credit Obligations (or, to the extent such Letter of Credit Obligations are contingent, to provide cash collateral in an amount up to 110% of such Letter of Credit Obligations) then due and payable until paid in full; (vii) seventh, ratably to pay the Revolving B Loans and Revolving C Loans in respect of any fees, expense reimbursements and indemnities then due to the Revolving B Loan Lenders and the Revolving C Loan Lenders until paid in full; (viii) eighth, ratably to pay interest due in respect of the Revolving B Loans and the Revolving C Loans until paid in full; (ix) ninth, ratably to pay principal of the Revolving B Loans and the Revolving C Loans then due and payable until paid in full; (x) tenth, ratably to pay the Revolving D Loans in respect of any fees, expense reimbursements and

-14-

indemnities then due to the Revolving D Loan Lenders until paid in full; (xi) eleventh, ratably to pay interest due in respect of the Revolving D Loans until paid in full; (xii) twelfth, ratably to pay principal of the Revolving D Loans then due and payable until paid in full; and (xiii) thirteenth, to the ratable payment of all other Obligations then due and payable.”

(b) Section 4.04(c) of the Financing Agreement is hereby amended and restated in its entirety as follows:

“In each instance, so long as no Event of Default has occurred and is continuing, Section 4.04(b) shall not be deemed to apply to any payment by the Borrower specified by the Borrower to the Funding Agent to be for the payment of the principal of or interest on the Revolving A Loans, the Revolving B Loans, the Revolving C Loans or the Revolving D Loans or other related Obligations then due and payable under any provision of this Agreement or the prepayment of all or part of the principal of the Revolving A Loans, the Revolving B Loans, the Revolving C Loans or the Revolving D Loans in accordance with the terms and conditions of Section 2.05.”

(c) Section 4.04 of the Financing Agreement is hereby amended by inserting immediately after clause (d) the following new clause (e):

“(e) Notwithstanding anything contained in this Agreement, including, without limitation, Section 4.04(b), after the occurrence and during the continuance of an Event of Default, 100% of the proceeds from any Collateral of ATP UK and 35% of the proceeds from the Disposition or issuance of any shares of Capital Stock of ATP UK shall be applied to the Obligations in the following order of priority: (i) first, ratably to pay the Revolving D Loans in respect of any fees, expense reimbursements and indemnities then due to the Revolving D Loan Lenders until paid in full; (ii) second, ratably to pay interest due in respect of the Revolving D Loans until paid in full; (iii) third, ratably to pay principal of the Revolving D Loans then due and payable until paid in full; (iv) fourth, ratably to pay the Obligations in respect of any fees (including any fees or charges assessed by the L/C Issuer), expense reimbursements, indemnities and other amounts then due to the Agents or the L/C Issuer until paid in full; (v) fifth, ratably to pay the Revolving A Loans in respect of any fees (including Letter of Credit Fees), expense reimbursements and indemnities then due to the Revolving A Loan Lenders until paid in full; (vi) sixth, ratably to pay interest due in respect of the Agent Advances until paid in full; (vii) seventh, ratably to pay principal of the Agent Advances until paid in full; (viii) eighth, ratably to pay interest due in respect of the Revolving A Loans and Letter of Credit Obligations until paid in full; (ix) ninth, ratably to pay principal of the Revolving A Loans and Letter of Credit Obligations (or, to the extent such Letter of Credit Obligations are contingent, to provide cash collateral in an amount up to 110% of such Letter of

-15-

Credit Obligations) then due and payable until paid in full; (x) tenth, ratably to pay the Revolving B Loans and Revolving C Loans in respect of any fees, expense reimbursements and indemnities then due to the Revolving B Loan Lenders and the Revolving C Loan Lenders until paid in full; (xi) eleventh, ratably to pay interest due in respect of the Revolving B Loans and the Revolving C Loans until paid in full; (xii) twelfth, ratably to pay principal of the Revolving B Loans and the Revolving C Loans then due and payable until paid in full; and (xiii) thirteenth, to the ratable payment of all other Obligations then due and payable.”

(d) Before giving effect to the amendment set forth in clause (c) above, Section 4.04(e) of the Financing Agreement shall be re-referenced and referred to as Section 4.04(f).

12. Use of Proceeds. Section 6.01(t) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“The proceeds of the Loans shall be used (a) to purchase the Existing Indebtedness of the Borrower in the outstanding principal amount of approximately $50,000,000, (b) to repay all of the Indebtedness of the Borrower under the Subordinated Note Documents, (c) to pay fees and expenses in connection with the transactions contemplated hereby, (d) to fund working capital of the Borrower, (e) subject to the terms and conditions contained in the Loan Documents, to repay any other outstanding Loans, and (f) subject to the terms and conditions set forth in Section 7.02(e), to fund working capital of the Foreign Subsidiaries and ATP UK in an aggregate amount not to exceed $17,500,000, provided, that, the funds made available to any of the Foreign Subsidiaries or ATP UK in excess of $7,500,000 shall be from the proceeds of the Revolving D Loans, and the funding of all such working capital shall be pursuant to a budget to be delivered by the Borrower to the Agents and which, with the consent of the Agents, may be updated by the Borrower from time to time, in each case the form and substance of which shall be satisfactory to the Agents in their sole discretion (the “Foreign Working Capital Budget”). The Letters of Credit will be used for general working capital purposes.”

13. Reporting Requirements. (a) Section 7.01(a)(viii) of the Financing Agreement is hereby amended by inserting immediately prior to the end of such Section, the following proviso:

“; provided, further, that on or prior to February 16, 2004, the Borrower shall deliver to the Agents the Reserve Report dated December 31, 2003 and such other information required to be delivered pursuant to Section 7.01(a)(vi), and shall deliver to the Agents a Borrowing Base Certificate and such other information required to be delivered pursuant to this Section 7.01(a)(viii), updating the NYMEX Strip Price as of January 31, 2004 and rolling forward

-16-

production and the classifications as to Proved Developed Producing Reserves, Proved Developed Non-Producing Reserves and Proved Undeveloped Reserves as of February 16, 2004, it being acknowledged by the parties that on and after February 16, 2004 until the delivery of an updated Borrowing Base Certificate pursuant to this Section 7.01(a)(viii), the Borrowing Base Certificate delivered pursuant to this proviso shall be the effective Borrowing Base Certificate”

(b) Section 7.01(a) of the Financing Agreement is hereby amended by deleting at the end of clause (xxiii) the word “and” and inserting immediately after clause (xxiii) the following new clauses (xxiv), (xxv), (xxvi) and (xxvii):

“(xxiv) on or prior to November 30, 2003, the Borrower shall have delivered to the Agents internally prepared weekly cash flow schedules as at the end of each week, for each period commencing at the end of the immediately preceding week and ending with the end of such week for the period from November 30, 2003 through March 5, 2004, which, with the consent of the Agents, may be updated by the Borrower from time to time (the “Weekly Cash Flow Schedules”), all in reasonable detail, and such weekly cash flow schedules shall include an updated Foreign Working Capital Budget, all in form and substance satisfactory to the Agents;

(xxv) not later than 60 days after June 30^th and December 31^st of each year (but, in the case of the UK Reserve Report dated December 31, 2003, not later than February 16, 2004), a reserve report related to ATP UK’s Oil and Gas Properties, similar in scope and substance to the Reserve Report (each such reserve report, the “UK Reserve Report”), prepared under the supervision of the chief engineer of the Borrower who shall certify the information contained in such reserve report to be true and accurate, and together with each such UK Reserve Report, a certificate of an Authorized Officer certifying that, to the best of his knowledge (A) the information contained in the UK Reserve Report and any other information delivered in connection therewith is true and correct, (B) ATP UK owns good and defensible title to its Oil and Gas Properties evaluated in such UK Reserve Report and such Oil and Gas Properties are free and clear of all Liens except for Permitted Liens, (C) except as set forth on an exhibit to the certificate, on a net basis there are no gas imbalances, take-or-pay or other prepayments with respect to such Oil and Gas Properties evaluated in such UK Reserve Report which would require the Borrower or its Subsidiaries to deliver Hydrocarbons produced from such Oil and Gas Properties or make cash payments at some future time without then or thereafter receiving full payment therefor, (D) except as set forth on an exhibit to the certificate, none of such Oil and Gas Properties have been sold since the date of the UK Reserve Report most recently delivered pursuant to this Section 7.01(a)(xxv), which exhibit shall list all of its Oil and Gas Properties sold and in such detail as is reasonably required by the Collateral Agent, (E) attached as an exhibit to the certificate is a list of such Oil and Gas

-17-

Properties added to and deleted from the UK Reserve Report most recently delivered pursuant to this Section 7.01(a)(xxv) and a list of all Persons disbursing proceeds to the Borrower or its Subsidiaries, as applicable, from such Oil and Gas Properties, (F) attached to the certificate as an exhibit is a list of all of the Oil and Gas Properties of ATP UK evaluated by such Reserve Report that are subject to a Mortgage, a Security Agreement or other security instrument, that in each case create a perfected, first priority Lien in such Oil and Gas Properties in favor of the Collateral Agent for the ratable benefit of the Lenders, except as to priority solely in respect of Permitted Liens that are inchoate Liens securing obligations for the payment of money not overdue or otherwise payable, and (G) except as set forth on an exhibit to such certificate, there has not been any change in the working interest or net revenue interest of ATP UK in any of the Oil and Gas Properties included on such UK Reserve Report, which change has occurred since the date of the last certificate delivered pursuant to this Section 7.01(a)(xxv), such exhibit to set forth the reason for such change;

(xxvi) as soon as available and in any event within 30 days after the end of each month, a report setting forth, in form reasonably acceptable to the Agents, the calculation of the UK PV-10 of the Proved Developed Producing Reserves, Proved Developed Non-Producing Reserves and Proved Undeveloped Reserves as determined by the UK Reserve Report most recently delivered by the Borrower under Section 7.01(a)(xxv), such calculation to be made by multiplying (x) the volumetric quantity of the categories of estimated Proved Reserves set forth in such UK Reserve Report less such aggregate projected production of Proved Reserves since the date of and as provided in such Reserve Report by (y) the applicable IPE Strip Price as of the last Business Day of the month preceding the date of the delivery by the Borrower of such report to the Agents; each such report shall (A) include a discussion of (I) any changes since the date of such Reserve Report in the categorization of any Oil and Gas Properties among Proved Developed Producing Reserves, Proved Developed Non-Producing Reserves, Proved Undeveloped Reserves and “other”, (II) any changes in the working interest or net revenue interest in the Oil and Gas Properties of ATP UK and reflected on such UK Reserve Report, (III) information related to any new Oil and Gas Properties in which ATP UK has an interest, including, without limitation, a description of such property, the license number, the royalty, working, operating or other interests or preferential rights of any other Person (including a brief description of each such interest) and any other information as the Agents may reasonably request, (IV) a report setting forth in a reasonable detail, all Oil and Gas Properties of ATP UK subject to licenses that will expire within 180 days thereof and the status of any extensions of such licenses, and (V) such other information as the Agents shall reasonably consider appropriate or necessary from the perspective of an asset-based lender; and (B) be accompanied by a certificate of an Authorized Officer of the Borrower certifying to the completeness and accuracy of the information (other than the projections of quantities of reserves)

-18-

set forth in the report, including the methodology for the calculation of the PV-10 of Proved Reserves;

(xxvii) as soon as available at the end of each week and in any event prior to Wednesday of the following week, a report setting forth the actual results on a weekly and cumulative basis for each item set forth in the Weekly Cash Flow Schedules in comparative form to the corresponding weekly or cumulative period, to be accompanied by a certificate of the Chief Financial Officer of the Borrower certifying as to the completeness and accuracy of the information set forth in such report; and”

(c) Before giving effect to the amendment set forth in clause (a) above, Section 7.01(a)(xxiv) of the Financing Agreement shall be renumbered and referred to as Section 7.01(a)(xxviii).

14. Negative Covenants.

(a) Section 7.02(a) of the Financing Agreement is hereby amended and restated to read as follows:

“Create, incur, assume or suffer to exist, or permit any of its Subsidiaries to create, incur, assume or suffer to exist, any Lien upon or with respect to any of its properties, whether now owned or hereafter acquired; file or suffer to exist under the Uniform Commercial Code or any similar law or statute of any jurisdiction, a financing statement (or the equivalent thereof) that names it or any of its Subsidiaries as debtor; sign or suffer to exist any security agreement authorizing any secured party thereunder to file such financing statement (or the equivalent thereof); sell any of its property or assets subject to an understanding or agreement, contingent or otherwise, to repurchase such property or assets (including sales of accounts receivable) with recourse to it or any of its Subsidiaries or assign or otherwise transfer, or permit any of its Subsidiaries to assign or otherwise transfer, any account or other right to receive income; other than, as to all of the above, Permitted Liens; provided, that, no Liens shall be permitted on any assets included in the Borrowing Base other than the Liens of the Collateral Agent for the benefit of the Lenders and any Permitted Lien that is an inchoate Lien securing obligations for the payment of money not overdue or otherwise payable.”

(b) Clause (iii) of Section 7.02(e) of the Financing Agreement immediately prior to the proviso is hereby amended and restated to read as follows:

“(iii) loans or advances to the Foreign Subsidiaries or ATP UK by the Borrower (x) existing on the Effective Date in an aggregate amount not exceeding $19,500,000 and (y) to be made by the Borrower after the Effective Date in an

-19-

aggregate amount from the Effective Date not to exceed $17,500,000 (such loans and advances, the “Foreign Loans”)”

(c) Subclause (I)(C) of clause (iii) of Section 7.02(e) of the Financing Agreement is hereby amended by deleting the reference to the date “February 28, 2004” and substituting in lieu thereof the date “February 16, 2004”.

(d) The following new subsection (y) is hereby added to Section 7.02 of the Financing Agreement:

“(y) Collateral Coverage. From and after February 16, 2004, permit the then applicable Borrowing Base to be less than an amount equal to 150% of the sum of the aggregate amount of the Revolving Loans and Letter of Credit Obligations.”

15. Financial Covenants. (a) Section 7.03(b) of the Financing Agreement is hereby amended by deleting the parenthetical “(in each case, other than the Foreign Subsidiaries)” and substituting in lieu thereof the parenthetical “(in each case, other than the Foreign Subsidiaries and ATP UK)”.

(b) Section 7.03(d) of the Financing Agreement is hereby amended by deleting the parenthetical “(in each case, other than the Foreign Subsidiaries)” and substituting in lieu thereof the parenthetical “(in each case, other than the Foreign Subsidiaries and ATP UK)”.

(c) Section 7.03(f) of the Financing Agreement is hereby amended and restated to read as follows:

“Permit an amount equal to the sum of (x) Cash and Cash Equivalents and Permitted Investments in the accounts specified in Section 8.01 and (y) the amount of Availability, to be less than $1,000,000 from the Effective Date until February 16, 2004, and $2,500,000 on and after February 16, 2004.”

16. Collection of Accounts Receivable; Management of Collateral. (a) The sixth, seventh and eighth sentences of Section 8.01(a) of the Financing Agreement are hereby amended and restated in their entirety to read as follows:

“Until the Funding Agent shall advise the Loan Parties to the contrary after the occurrence and during the continuance of an Event of Default, the Loan Parties may and will enforce, collect and receive all amounts owing on the Accounts Receivable of the Loan Parties for and on the Funding Agent’s benefit and behalf, but at the Loan Parties’ expense, and such privilege shall terminate, at the election of any Agent, upon the occurrence and during the continuance of an Event of Default. So long as Availability is not greater than $20,000,000, the Funding Agent shall have the right to direct all funds received in the Collection Accounts to be sent by wire transfer or Automated Clearing House, Inc. payment

-20-

to the Funding Agent’s Account for application at the end of each Business Day to reduce the then principal balance of the Revolving Loans, conditional upon final payment to the Funding Agent.”

(b) Section 8.01(a) of the Financing Agreement is hereby amended by inserting immediately prior to the end of such Section, the following paragraph:

“On or prior to December 10, 2003, ATP UK shall (i) establish and maintain one or more depository accounts, under the dominion and control of the Funding Agent pursuant to a blocked account agreement among the Funding Agent, ATP UK and the applicable English financial institution, in form and substance satisfactory to the Agents, in respect of its Collections and (ii) instruct all of its Account Debtors to remit all such Collections to such depository accounts. ATP UK shall at all times deposit all Collections into such accounts that are received by it from any source promptly, and in any event no later than the first Business Day, after the date of receipt thereof. So long as no Event of Default shall have occurred and be continuing, ATP UK may use the funds on deposit in its bank accounts for its working capital purposes. During the continuance of an Event of Default, the Funding Agent shall have the right to convert all non-Dollar denominated balances in ATP UK’s bank accounts into Dollars (at the Loan Parties’ sole expense) and cause all amounts in such accounts to be wired into the Funding Agent’s Account or a Collection Account. The arrangements contemplated in Section 8.01(a) may not be modified by any Loan Party or any other Subsidiary of any Loan Party without the prior written consent of the Agents.”

17. Events of Default. (a) Clause (t) of Section 9.01 of the Financing Agreement is hereby amended by deleting the word “or” immediately after the semicolon and (b) immediately after clause (u) of Section 9.01 of the Financing Agreement, the following new clauses (v), (w), (x) and (y) are hereby inserted:

“(v) a Material Adverse Deviation shall have occurred;

(w) on or prior to March 1, 2004, ATP UK shall fail to produce Hydrocarbons from the Helvellyn field in the United Kingdom sector of the North Sea in an amount less than 12.5 mcfe of Hydrocarbons each day;

(x) the aggregate amount of the Hydrocarbons produced by the Borrower, net to the Borrower’s interest, in the United States in any calendar month shall be less than 20% of the aggregate amount of Hydrocarbons produced by the Borrower, net to the Borrower’s interest, in the United States in the immediately preceding month; or

(y) at the end of each calendar month, commencing on December 31, 2003, the NYMEX Strip Price for the majority of categories of crude oil or

-21-

natural gas produced by the Loan Parties shall be less than 20% of the NYMEX Strip Price for such applicable categories at the end of the immediately preceding calendar month;”

18. Lenders’ Commitments. Schedule 1.01(A) of the Financing Agreement is hereby amended and restated in its entirety as set forth in Exhibit A hereto.

19. Schedules. Each of Schedule 6.01(o), 6.01(s), 6.01(v), 6.01(x), 6.01(dd), and 6.01(ff) of the Financing Agreement is hereby modified and revised to include all information required to be provided therein with respect to, and solely with respect to, ATP UK, each as set forth in Exhibit B-1, Exhibit B-2, Exhibit B-3, Exhibit B-4, Exhibit B-5 and Exhibit B-6, respectively.

20. Conditions to Effectiveness. The effectiveness of this Amendment (the date of such effectiveness, the “Amendment Effective Date”) is subject to the conditions precedent that:

(a) this Amendment shall have been duly executed by an Authorized Officer of the Borrower and each Guarantor and the Agents and the Lenders, original counterparts of which shall have been delivered to the Administrative Agent;

(b) each of the representations and warranties made by each Loan Party in or pursuant to the Loan Documents shall be true and correct in all material respects on and as of the Amendment Effective Date as if made on and as of such date (unless such representations and warranties are stated to relate to a specific earlier date, in which case such representations and warranties shall be true and correct in all material respects as of such earlier date);

(c) no Default or Event of Default shall have occurred and be continuing on such date or after giving effect to this Amendment;

(d) the Administrative Agent shall, for the ratable benefit of the Lenders, have received a fee equal to $375,000 as set forth in the Supplemental Fee Letter, dated as of November 14, 2003, from the Borrower to the Agents;

(e) the Administrative Agent shall have received copies of the resolutions of the Borrower, certified as of the Amendment Effective Date, by an Authorized Officer, the Secretary or an assistant secretary thereof, authorizing (i) the increase in the Commitments and (ii) the execution, delivery and performance by the Borrower of this Agreement;

(f) the Agents shall have received an opinion of counsel to the Loan Parties as to such other matters as the Agents may reasonably request;

-22-

(g) the Administrative Agent shall have received copies of each Material Contract as in effect on the Amendment Effective Date, each of which is set forth on Exhibit B-4, certified by an Authorized Officer of the Borrower as true and correct copies of the relevant Material Contracts, together with a certificate of an Authorized Officer of the Borrower stating that such Material Contracts remain in full force and effect and that none of the Loan Parties has breached or defaulted in any of its obligations under such Material Contracts;

(h) substantially contemporaneously with the satisfaction of each of the other conditions precedent set forth in this paragraph 20, the Administrative Agent shall have received each of the following documents, duly executed and/or delivered by ATP UK, each in form and substance satisfactory to the Administrative Agent (it being understood and agreed that the delivery of such documents hereunder shall satisfy the requirements specified therefor under the Consent and Amendment No. 1 to the Financing Agreement, dated as of November 14, 2003 (“Amendment No. 1”) to deliver such documents on or prior to December 3, 2003, as such date was extended by the Overadvance Letter, dated as of November 26, 2003, from the Agents and the Lenders to the Borrower and the Guarantor): (i) a Debenture, made by ATP UK made in favor of the Administrative Agent for the benefit of the Agents and the Lenders (the “Debenture”), (ii) a Charge Over Shares, made ATP in favor of the Administrative Agent for the benefit of the Agents and the Lenders (the “Charge Over Shares”), (iii) a notice of charge in relation to the Charged Accounts (as such term is defined in the Debenture), duly executed by ATP UK and delivered to the financial institution where the Charged Accounts are established (the “Charged Accounts Notice”), (iv) a stamped and undated stock transfer form, duly executed by the Borrower in respect of the remaining Capital Stock of ATP UK pledged to the Administrative Agent, (v) evidence that the Secretary of State has consented to the security interests created by the Debenture and the Charge over Shares, (vi) organizational documents of ATP UK, each certified by an officer of ATP UK, including, without limitation, its memorandum and articles of association and resolutions and/or consents related to the transactions contemplated by this Amendment, the Debenture and the Charge Over Shares, and (vii) such other agreements, instruments or other documents required by the Agents;

(i) the Administrative Agent shall have received satisfactory evidence that the Administrative Agent for the benefit of the Agents and the Lenders, shall have been granted Liens on substantially all of the assets of ATP UK, including, without limitation, Liens on the UK Oil and Gas Properties, and such Liens shall be validly perfected, first priority on such assets and properties, and the Loan Parties shall have satisfied each other agreement set forth in Paragraph 9(b) of Amendment No. 1;

(j) the Agents shall have received updated Weekly Cash Flow Schedules (as defined in Amendment No. 1 to the Financing Agreement), which updated Weekly Cash Flow Schedules shall be the same as the Weekly Cash Flow Schedules delivered pursuant to Amendment No. 1 to the Financing Agreement, but shall set forth a new line item for disbursements by ATP UK to develop its Oil and Gas Properties at Helvellyn, all in form and substance satisfactory to the Agents and which updated Weekly Cash Flow Schedules, shall be certified by the Chief Financial Officer of the Borrower and attached hereto as Exhibit C; and

-23-

(k) all other legal matters incident to this Amendment shall be satisfactory to the Agents and their counsel.

21. Representations and Warranties. Each of the Loan Parties hereby jointly and severally represents and warrants to the Agents and the Lenders as follows:

(a) Each of the Loan Parties has all requisite power and authority to execute, deliver and perform this Amendment, and to perform the Financing Agreement, as amended hereby.

(b) The execution, delivery and performance of this Amendment by each of the Loan Parties, and the performance by each of the Loan Parties of the Financing Agreement, as amended hereby, (i) have been duly authorized by all necessary action, (ii) do not and will not contravene its charter or by-laws, its limited liability company or operating agreement or its certificate of partnership or partnership agreement, as applicable, or any applicable law or any contractual restriction binding on or otherwise affecting it or any of its properties, (iii) do not and will not result in or require the creation of any Lien (other than pursuant to any Loan Document) upon or with respect to any of its material properties, and (iv) do not and will not result in any material default, noncompliance, suspension, revocation, impairment, forfeiture or nonrenewal of any material permit, license, authorization or approval applicable to its operations or any of its properties.

(c) No authorization or approval or other action by, and no notice to or filing with, any Governmental Authority is required in connection with the due execution, delivery and performance by any Loan Party of this Amendment or the performance by any Loan Party of the Financing Agreement, as amended hereby.

(d) This Amendment and the Financing Agreement, as amended hereby, constitute the legal, valid and binding obligations of each Loan Party, enforceable against such Persons in accordance with their terms, except as may be limited by applicable bankruptcy, insolvency, reorganization, moratorium or other similar laws.

22. Post-Closing Deliveries. Each of the Loan Parties and ATP UK shall deliver or cause to be delivered to the Agents the following:

(a) on or prior to December 10, 2003, title opinions of the Borrower’s counsel or other evidence satisfactory to the Agents of the title of ATP UK to its Oil and Gas Properties;

(b) on or prior to December 10, 2003, opinions of counsel in the United Kingdom as to such matters as the Agents reasonably request; and

(c) on or prior to December 18, 2003, appropriate additional insured and loss payable endorsement certificates in favor of the Administrative Agent for the benefit of

-24-

the Agents and the Lenders, in form and substance reasonably satisfactory to the Agents from the insurance providers of ATP UK.

23. Ratification. Except as otherwise expressly provided herein, each Loan Party confirms and agrees that (a) each Loan Document to which it is a party is, and shall continue to be, in full force and effect and is hereby ratified and confirmed in all respects except that on and after the date on which this Amendment is effective all references in any such Loan Document to “the Financing Agreement”, “thereto”, “thereof”, “thereunder”, or words of like import referring to the Financing Agreement shall mean the Financing Agreement as amended by this Amendment, and (b) to the extent that any such Loan Document purports to assign or pledge to the Administrative Agent, or to grant to the Administrative Agent a security interest in or lien on, any collateral as security for its obligations from time to time existing in respect of the Loan Documents, such pledge, assignment and/or grant of a security interest or lien is hereby ratified and confirmed in all respects as security for all of its obligations, whether now existing or hereafter arising. This Amendment does not and shall not affect any Obligation or Guarantee Obligation (as the case may be), other than as expressly provided herein, of any Loan Party under or arising from the Financing Agreement or any other Loan Document, all of which obligations are hereby ratified and shall remain in full force and effect. Except as expressly provided herein, the execution, delivery and effectiveness of this Amendment shall not operate as a waiver of any right, power or remedy of the Agents or the Lenders under the Financing Agreement or any other Loan Document, nor constitute a waiver of any provision of the Financing Agreement or any other Loan Document.

24. Expenses. The Borrower hereby agrees to pay to the Agents upon demand the amount of any and all fees, costs and expenses, including the reasonable fees, disbursements and other client charges of the Agents’ counsel, which the Agents may incur in connection with this Amendment, the amounts of which the Borrower agrees may be charged to the Loan Account.

25. Counterparts. This Amendment may be executed in any number of counterparts and by the different parties hereto in separate counterparts, each of which shall be deemed to be an original, but all of which taken together shall constitute one and the same waiver. Delivery of an executed counterpart of this Amendment by telecopier or by electronic mail shall be equally as effective as delivery of an original executed counterpart of this Amendment.

26. Governing Law. This Amendment shall be governed by and construed in accordance with the law of the State of New York applicable to contracts made and to be performed within such state.

-25-

IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed and delivered by their duly authorized officers as of the date first above written.

AGENTS AND LENDERS:
ABLECO FINANCE LLC, as Collateral Agent, Administrative Agent and Lender, for itself as a Lender and on behalf of its affiliate assigns as Lenders
By:	/s/    KEVIN GENDA
Title:	Senior Vice President

WELLS FARGO FOOTHILL, INC., as Funding Agent and Lender
By:	/s/    DREW STAWIN
Title:	Senior Vice President
BORROWER:
ATP OIL & GAS CORPORATION
By:	/s/    ALBERT L. REESE, JR.
Title:	Senior Vice President
GUARANTORS:
ATP ENERGY, INC.
By:	/s/    ALBERT L. REESE, JR.
Title:	Senior Vice President
ATP OIL & GAS (UK) LIMITED
By:	/s/    T. PAUL BULMAHN
Title:	Director

EX-10.2

Exhibit 10.2

CONSENT AND AMENDMENT NO. 3

TO THE

SECOND AMENDED AND RESTATED

FINANCING AGREEMENT

THIS CONSENT AND AMENDMENT NO. 3, dated as of February 16, 2004 (this “Amendment”), to the Second Amended and Restated Financing Agreement, dated as of August 13, 2003, as amended pursuant to the Consent and Amendment No. 1, dated as of November 14, 2003, and Amendment No. 2, dated as of December 3, 2003, and as supplemented by the Joinder Agreement, dated as of December 3, 2003 (as amended, supplemented or otherwise modified from time to time, the “Financing Agreement”), by and among ATP Oil & Gas Corporation, a Texas corporation (the ”Borrower”), each subsidiary of the Borrower listed as a “Guarantor” on the signature pages thereto (together with ATP Oil & Gas (UK) Limited, each a “Guarantor” and collectively, the “Guarantors” and, together with the Borrower, each a “Loan Party” and collectively, the “Loan Parties”), each of the lenders from time to time party thereto (each a “Lender” and collectively, the ”Lenders”), Ableco Finance LLC, a Delaware limited liability company (“Ableco”), as collateral agent and administrative agent for the Lenders (in such capacity, the ”Collateral Agent” or the “Administrative Agent”), and Wells Fargo Foothill, Inc., a California corporation (“Foothill”), as funding agent for the Lenders (in such capacity, the “Funding Agent”, and together with the Administrative Agent and the Collateral Agent, each an “Agent” and collectively the “Agents”).

W I T N E S S E T H:

WHEREAS, pursuant to the Financing Agreement among the Borrower, the Guarantors, each of the Lenders from time to time party thereto, Ableco, in its capacity as the Collateral Agent and Administrative Agent for the Lenders, and Foothill, in its capacity as Funding Agent for the Lenders, the Lenders have agreed to make certain revolving loans, which includes a subfacility for the issuance of Letters of Credit (as defined in the Financing Agreement), to the Borrower;

WHEREAS, the Borrower has advised the Lenders that the Borrower is in default under certain financial covenants set forth in the Financing Agreement and has requested a waiver of such defaults, and has requested certain amendments to the Financing Agreement; and

WHEREAS, the Lenders have agreed to waivers of such defaults and to such amendments subject to the conditions set forth herein;

NOW, THEREFORE, in consideration of the premises and agreements herein, the parties hereto hereby agree as follows:

1. Definitions. All terms used herein that are defined in the Financing Agreement and not otherwise defined herein are used herein as defined therein.

2. Changes to Definitions. Each of the following definitions set forth in Section 1.01 of the Financing Agreement is hereby amended, restated, modified, supplemented, deleted or added:

(a) The definition of “Availability” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Availability’ means, at any time, the difference between (a) (i) the lesser of (x) the Borrowing Base and (y) the sum of the Total Revolving A Credit Commitment, the Total Revolving B Credit Commitment and the Total Revolving C Credit Commitment minus (ii) the sum of (A) the aggregate outstanding principal amount of all Revolving A Loans, Revolving B Loans, Revolving C Loans and Letter of Credit Obligations and (B) the Availability Reserve, and (b) the aggregate amount, if any, of all trade payables of the Borrower and its Subsidiaries (other than the Foreign Subsidiaries) aged in excess of historical levels.”

(b) Subclause (y) of the first proviso of the definition of “Borrowing Base” contained in Section 1.01 of the Financing Agreement is hereby amended by deleting the amount $20,000,000” and substituting “$25,000,000” in lieu thereof.

(c) The second proviso of the definition of “Borrowing Base” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“provided, further, that (I) for the period from the Effective Date through and including March 31, 2004, (AA) the percentage advance rate applicable to Proved Undeveloped Reserves set forth in clause (iii) shall equal 30%, (BB) the percentage limitation set forth in subclause (x) of the immediately preceding proviso shall equal 60%, and (CC) the dollar limitation set forth in subclause (y) of the immediately preceding proviso shall equal $45,000,000, and (II) for the period from and including April 1, 2004 through and including April 30, 2004, (AA) the percentage advance rate applicable to Proved Undeveloped Reserves set forth in clause (iii) shall equal 25%, (BB) the percentage limitation set forth in subclause (x) of the immediately preceding proviso shall equal 50%, and (CC) the dollar limitation set forth in subclause (y) of the immediately preceding proviso shall equal $35,000,000”

-2-

(d) The definition of the term “Consolidated EBITDA” contained in Section 1.01 of the Financing Agreement is hereby amended by deleting the word “and” immediately preceding clause (E) and substituting a comma in lieu thereof and inserting immediately prior to the period at the end of such definition the following clauses (F) and (G) to read as follows:

“, (F) any accruals for, and payments of (to the extent such payments were not accrued), the Legacy Award, and (G) fees accruals for, and payments of (to the extent such payments were not accrued), fees by the Borrower to the Agents and Lenders in connection with amendments to this Agreement, provided that such amount described in this clause (G) shall be added for purposes of calculating Consolidated EBITDA solely for purposes of calculating compliance with any financial covenant for the fiscal periods ended January 31, 2004, February 29, 2004, March 31, 2004 and April 30, 2004 and shall not be added for purposes of calculating compliance with any financial covenant for any other fiscal period”

(e) The definition of the term “Consolidated Funded Indebtedness” contained in Section 1.01 of the Financing Agreement is hereby amended by (i) inserting immediately prior to the phrase “, but excluding” the following phrase “and all cash payments required to be made by the Borrower to holders of its preferred Capital Stock issued pursuant to the Permitted Preferred Equity Issuance”, (ii) inserting a clause “(i)” immediately prior to the phrase “any obligations of such Person” and (iii) inserting immediately prior to the period at the end of such definition a new clause (ii) to read as follows:

“and (ii) any liabilities constituting Indebtedness in respect of the Legacy Award”

(f) Clause (ii) of the definition of the term “Final Maturity Date” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“with respect to the Total Revolving D Credit Commitment, January 31, 2005,”

(g) The definition of the term “Loan Document” contained in Section 1.01 of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“ ‘Loan Document’ means this Agreement, the Assignment Documents, the Fee Letter, any Guaranty, any Security Agreement, any Pledge Agreement, any Mortgage, any Letter of Credit Application, the Warrant Agreements, the Registration Rights Agreement and any other agreement, instrument, and other document executed and delivered pursuant hereto or thereto or otherwise evidencing or securing any Loan, any Letter of Credit Obligation or any other Obligation.”

-3-

3. New Definitions. Each of the following definitions of the terms “Availability Blockage Date”, “Availability Reserve”, “Common Stock”, “Legacy”, “Legacy Award”, “Legacy Settlement”, “Permitted Preferred Equity Issuance”, “Registration Rights Agreement”, “Warrants”, “Warrant Agreements”, “Warrant Holders” and “Warrant Stock” is hereby added to Section 1.01 of the Financing Agreement in the appropriate alphabetical order:

“ ‘Availability Blockage Date’ means the earlier of (i) April 30, 2004 and (ii) the date on which the Permitted Preferred Equity Issuance shall have been consummated.”

“ ‘Availability Reserve’ means an amount equal to the sum of (i) for the period commencing February 16, 2004 and ending April 30, 2004, or such later date as may be determined by the Agents at their sole discretion, $2,000,000, and (ii) on and after the Availability Blockage Date, $14,000,000.”

“ ‘Common Stock’ means the Common Stock of the Borrower, par value $0.001 per share.”

“ ‘Legacy’ means Legacy Resources Co., L.P.”

“ ‘Legacy Award’ means the award by the arbitration panel in the matter styled Legacy Resources Co., LP, Claimant, against ATP Oil & Gas Corporation, Respondent, dated December 16, 2003, in favor of Legacy.”

“ ‘Legacy Settlement’ means the settlement arrangements to be entered into between Legacy and the Borrower to satisfy the payment of the Borrower of the Legacy Award, such arrangement to be on terms and conditions acceptable to the Agents in their sole discretion.”

“ ‘Permitted Preferred Equity Issuance’ has the meaning specified therefor in Section 7.02(l).”

“ ‘Registration Rights Agreement’ means the Registration Rights Agreement, in form and substance satisfactory to the Agents, by and between the Borrower and each Warrant Holder, with respect to the demand and piggy-back registration rights of each Warrant Holder with respect to shares of Warrant Stock that any such Warrant Holder may acquire and the anti-dilution and tag-along provisions applicable thereto.”

“ ‘Warrants’ has the meaning specified therefor in Section 12.01.”

“ ‘Warrant Agreements’ has the meaning specified therefor in Section 12.01.”

“ ‘Warrant Holders’ means the holders of any of the Warrant Agreements.”

“ ‘Warrant Stock’ has the meaning specified therefor in Section 12.01.”

-4-

4. Commitments.

(a) Section 2.01(b)(i) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(i) The aggregate principal amount of Revolving A Loans outstanding at any time to the Borrower shall not exceed the difference between (A) the lesser of (x) the Total Revolving A Credit Commitment and (y) 100% of the amount attributable to clause (i) of the definition of “Borrowing Base”, and (B) the sum of (I) the aggregate Letter of Credit Obligations and (II) if the Availability Reserve exceeds the Total Revolving B Credit Commitment and the Total Revolving C Credit Commitment, the amount of such excess of the Availability Reserve.”

(b) Section 2.01(b)(ii) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

(ii) The aggregate principal amount of Revolving B Loans outstanding at any time to the Borrower shall not exceed the difference between (A) Total Revolving B Credit Commitment and (B) if the Availability Reserve exceeds the Total Revolving C Credit Commitment, the amount of such excess of the Availability Reserve.”

(c) Section 2.01(b)(iii) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(iii) The aggregate principal amount of Revolving C Loans outstanding at any time to the Borrower shall not exceed the difference between (x) the Total Revolving C Credit Commitment and (y) the Availability Reserve.”

(d) Section 2.01(b)(v) of the Financing Agreement is hereby amended by inserting immediately prior to the period at the end of such Section, the following proviso:

“(v) The aggregate principal amount of the Revolving A Loans, the Revolving B Loans and the Revolving C Loans outstanding at any time to the Borrower shall not exceed the lower of (A) the difference between (x) the sum of the Total Revolving A Credit Commitment, the Total Revolving B Credit Commitment and the Total Revolving C Credit Commitment and (y) the sum of the aggregate Letter of Credit Obligations and the Availability Reserve, and (B) the difference between (x) the then current Borrowing Base and (y) the sum of the aggregate Letter of Credit Obligations and the Availability Reserve.”

5. Repayment of Loans; Evidence of Debt. The proviso set forth in Section 2.03(a) of the Financing Agreement is hereby deleted in its entirety.

6. Interest. Section 2.04(a)(iii) of the Financing Agreement is hereby amended by deleting the date “February 16, 2004” and substituting the date “January 31, 2005” in lieu thereof.

-5-

7. Reduction of Commitment; Prepayment of Loans. Section 2.05(a)(i) of the Financing Agreement is hereby amended and restated in its entirety as follows:

“(i) Each of the Total Revolving A Credit Commitment, the Total Revolving B Credit Commitment, the Total Revolving C Credit Commitment and the Total Revolving D Credit Commitment shall terminate on the applicable Final Maturity Date; provided, however, that, (x) if on January 31, 2005, the then applicable Borrowing Base is less than $110,000,000, the Total Revolving C Credit Commitment shall terminate, (y) unless all of the Revolving D Lenders otherwise agree, (A) each prepayment (whether pursuant to an optional, scheduled or mandatory prepayment) of the Revolving D Loans shall result in a permanent reduction in the Total Revolving D Credit Commitment in an amount equal to the amount of such prepayment and (B) on the last day of each month, commencing May 31, 2004, if the aggregate amount of commitment reductions to the Total Revolving D Credit Commitment as a result of a mandatory prepayment pursuant to Section 2.05(c)(x) during such month is less than $500,000, the Total Revolving D Credit Commitment shall be permanently reduced in an amount equal to the difference between (I) $500,000 and (II) the aggregate amount of commitment reductions as a result of a mandatory prepayment pursuant to Section 2.05(c)(x) during such month, and (z) any prepayment of the Revolving Loans as a result of a mandatory prepayment required pursuant to Section 2.05(c)(ix) shall result in a permanent reduction in the applicable Total Revolving Credit Commitment to which such payment is applied in an amount equal to the amount of such prepayment.”

8. Mandatory Prepayments. (a) Clause (i) of Section 2.05(c) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(i) If at any time the aggregate principal amount of the sum of the Revolving A Loans, the Revolving B Loans and the Revolving C Loans plus the outstanding amount of all Letter of Credit Obligations exceeds the difference between the Borrowing Base and the Availability Reserve, the Borrower will immediately prepay the applicable Revolving Loans to the full extent of any such excess in accordance with Section 2.05(d). On each day that any Revolving A Loan, Revolving B Loan, Revolving C Loan or Letter of Credit Obligations are outstanding, the Borrower shall hereby be deemed to represent and warrant to the Agents and the Lenders that the difference between the Borrowing Base and the Availability Reserve calculated as of such day equals or exceeds the aggregate principal amount of all Revolving A Loans, Revolving B Loans, Revolving C Loans and Letter of Credit Obligations outstanding on such day. If, at any time after the Borrower has complied with the first sentence of this Section 2.05(c)(i), the aggregate Letter of Credit Obligations is greater than the lesser of (A) the then current Borrowing Base minus the Availability Reserve and (B) the Total Revolving A Credit Commitment, provided, that, for purposes of calculating the

-6-

immediately preceding clause (B), if the Availability Reserve exceeds the sum of the Total Revolving B Credit Commitment and the Total Revolving C Credit Commitment, the amount in excess of the Availability Reserve shall be deducted from clause (B), the Borrower shall provide cash collateral to the Funding Agent in an amount equal to 110% of such excess, which cash collateral shall be deposited in an account under the sole and exclusive control of the Funding Agent for the benefit of the Agents, the Lenders and/or the L/C Issuer and, provided that no Event of Default shall have occurred and be continuing, such cash collateral shall be returned to the Borrower, at such time as the aggregate Letter of Credit Obligations plus the aggregate principal amount of all outstanding Revolving Loans no longer exceeds the lesser of (A) the then current Borrowing Base minus the Availability Reserve and (B) the Total Revolving A Credit Commitment, provided, that, for purposes of calculating the immediately preceding clause (B), if the Availability Reserve exceeds the difference between (x) the sum of the Total Revolving B Credit Commitment and the Total Revolving C Credit Commitment, the amount in excess of the Availability Reserve shall be deducted from clause (B).”

(b) Clause (viii) of Section 2.05(c) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(viii) Commencing on the earlier of (x) the payment in full of all of the Revolving D Loans and (y) February 1, 2005, immediately upon receipt by the Borrower of any amount from any Foreign Subsidiary or ATP UK related to the Foreign Loans, the Borrower shall prepay the outstanding principal of the Revolving Loans in an amount equal thereto.”

(c) Section 2.05(c) of the Financing Agreement is hereby amended by inserting immediately after clause (viii) the following new clauses (ix) and (x):

“(ix) If any Loan Party or any of its Subsidiaries shall make a payment to satisfy the Legacy Award (either pursuant to the Legacy Settlement or otherwise) either (x) on or prior to April 30, 2004, or (y) after April 30, 2004 if Availability is or will be, after giving effect to such payment, less than $5,000,000, the Borrower shall, immediately prior to the making of such payment, prepay the outstanding principal amount of the Revolving Loans in an amount equal to the amount of such payment.”

“(x) Until the earlier of (x) the payment in full of all of the Revolving D Loans and (y) January 31, 2005, immediately upon receipt of cash proceeds by ATP UK from its operations in the Helvellyn field in the North Sea—UK Sector, the Borrower shall prepay the outstanding principal amount of the Revolving D Loans in an amount equal to (A) for the period commencing May 1, 2004 through and including July 31, 2004, 75% of the aggregate cash proceeds received

-7-

therefrom (less any operating expenses, including, without limitation, any expenses related to royalties, severance taxes, commissions and other cash expenses (which other cash expenses shall be consistent with such estimates set forth in the UK Reserve Report) directly attributable to production from such field), and (B) from and after August 1, 2004, 50% of the aggregate cash proceeds received therefrom (less any operating expenses, including, without limitation, any expenses related to royalties, severance taxes, commissions and other cash expenses (which other cash expenses shall be consistent with such estimates set forth in the UK Reserve Report) directly attributable to production from such field).”

9. Application of Payments. (a) Section 2.05(d) of the Financing Agreement is hereby amended by deleting the word “and” and substituting a comma in lieu thereof and adding, immediately after the reference to clause “(c)(viii)” the phrase “, (c)(ix) and (c)(x)”.

(b) Section 2.05(d)(i) of the Financing Agreement is hereby amended by deleting the word “or” immediately prior to the phrase “any Collections of ATP UK” and substituting a comma in lieu thereof and adding, immediately after such phrase, the following “or any events described in Section 2.05(c)(ix) and Section 2.05(c)(x)”.

10. Letter of Credit Guaranty. The first sentence of Section 3.01(b) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“The aggregate Letter of Credit Obligations shall not exceed the lowest of (i) the difference between (A) the Total Revolving A Credit Commitment and (B) the aggregate principal amount of all Revolving A Loans then outstanding, (ii) the difference between (A) the Borrowing Base minus the Availability Reserve and (B) the aggregate principal amount of all Revolving A Loans, Revolving B Loans and Revolving C Loans then outstanding, and (iii) the L/C Subfacility; provided, however, that, for purposes of calculating the immediately preceding clause (ii), if the aggregate amount of the Availability Reserve exceeds the Total Revolving B Credit Commitment and the Total Revolving C Credit Commitment, the amount in excess of the Availability Reserve shall be deducted from the immediately preceding clause (ii).”

11. Use of Proceeds. Clause (f) of Section 6.01(t) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(f) subject to the terms and conditions set forth in Section 7.02(e), to fund working capital of the Foreign Subsidiaries and ATP UK in an aggregate amount not to exceed $21,000,000, provided, that, the funds made available to any of the Foreign Subsidiaries or ATP UK in excess of $7,500,000 shall be from the proceeds of the Revolving D Loans and the funds made available on and after February 16, 2004, shall be made available only to ATP UK, and the funding of all such working capital shall be pursuant to a budget to be delivered by the

-8-

Borrower to the Agents and which, with the consent of the Agents, may be updated by the Borrower from time to time and shall be updated on February 16, 2004, in each case the form and substance of which shall be satisfactory to the Agents in their sole discretion (the “Foreign Working Capital Budget”)”

12. Reporting Requirements. (a) Section 7.01(a)(vi) of the Financing Agreement is hereby amended by inserting immediately after the phrase “not later than 60 days after June 30^th and December 31^st of each year” and immediately prior to the comma, the parenthetical “(except as otherwise provided in Section 7.01(a)(viii))”.

(b) Section 7.01(a)(viii) of the Financing Agreement is hereby amended by (i) deleting the three references to the date “February 16, 2004” and substituting the date “March 15, 2004” in lieu thereof, (ii) deleting the single reference to the date “January 31, 2004” and substituting the date “February 29, 2004” in lieu thereof, and (iii) inserting immediately prior to the semicolon at the end of such section, the following:

“, and commencing February 16, 2004 until the date on which the Agents receive a satisfactory Reserve Report dated December 31, 2003 referred to in this proviso, the Borrowing Base shall be determined based upon the interim draft Reserve Report and which information contained therein shall be adjusted by the Agents in their sole discretion, based upon, among other things, a review by Netherland & Sewell”

13. Borrowing Base. Section 7.01(p) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(p) Maintain all Revolving A Loans, Revolving B Loans, Revolving C Loans and Letter of Credit Obligations in compliance with the then current Borrowing Base minus the Availability Reserve.”

14. Additional Affirmative Covenant. Section 7.01 of the Financing Agreement shall be amended by adding the following new clause (v) at the end of such Section:

“(v) Brazos 544. On or before February 29, 2004, complete, or cause to be completed, all work and take such other actions as are necessary in respect of the compression job related to the Proved Reserves referred to as Brazos 544.”

15. Loans, Advances, Investments, Etc. (a) Clause (iii) of Section 7.02(e) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(iii) loans or advances to the Foreign Subsidiaries or ATP UK by the Borrower (x) existing on the Effective Date in an aggregate amount not exceeding $19,500,000, and (y) after the Effective Date through April 30, 2004, in an aggregate amount not to exceed $21,000,000 (such loans and advances described in clauses (x) and (y), the “Foreign Loans”), provided, that, (I) before and after

-9-

giving effect to each such Foreign Loan (A) no Default or Event of Default exists, (B) the liabilities (including, without limitation, all production taxes and royalty or other lease payments) of the Loan Parties are current, (C) Availability is greater than $2,500,000, and (D) no other provision in this Agreement would be violated thereby, (II) each such Foreign Loan is made in accordance with the most recent Foreign Working Capital Budget, (III) each such Foreign Loan once repaid or prepaid may not be reborrowed, (IV) the proceeds of each such Foreign Loan are used to fund working capital of ATP UK related to its Oil and Gas Properties located in the jurisdiction of the United Kingdom commonly referred to as the UK Sector — North Sea and ATP Netherlands related to its Oil and Gas Properties located in the jurisdiction of the Netherlands commonly referred to as the Netherlands Sector – North Sea, and, in the case of proceeds of each such Foreign Loan made after February 16, 2004, are used solely to fund working capital of ATP UK related to the Helvellyn field in the North Sea — UK Sector, and, in the case of such Foreign Loans made on and after February 16, 2004, to fund working capital of ATP UK related to its Oil and Gas Properties referred to as Helvellyn, and (V) at the end of each month, commencing upon the earlier of January 31, 2005 and the month in which all of the Revolving D Loans have been paid in full, the Loan Parties shall pay, or cause to be paid, the Foreign Loans in a principal amount equal to not less than $500,000”

(b) Subclause (x) of the proviso contained in Section 7.02(e)(vi) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(x) the excess of the Borrowing Base minus the Availability Reserve over the sum of the aggregate outstanding principal amount of all Revolving A Loans, Revolving B Loans, Revolving C Loans and all Letter of Credit Obligations would be $2,500,000 or greater”

16. Capital Expenditures. Section 7.02(g) of the Financing Agreement is hereby amended by (i) deleting the word “and” immediately prior to clause (ii), and (ii) adding immediately prior to the period at the end of the first sentence the following new clause (iii):

“; and (iii) for the period commencing February 1, 2004 through and including April 30, 2004, any Capital Expenditures related to (x) the Oil and Gas Property referred to as Garden Banks 186 that would cause the incurrence of such expenditures to exceed $9,682,200 for such period, (y) the Oil and Gas Property referred to as Ship Shoal 358 that would cause the incurrence of such expenditures to exceed $4,862,500 for such period, and (z) the Oil and Gas Property referred to as Matagorda Island that would cause the incurrence of such expenditures to exceed $3,608,750 for such period”

17. Restricted Payments. (a) The first proviso of Section 7.02(h) of the Financing Agreement is hereby amended by (i) deleting the word “and” immediately prior to

-10-

clause (C) and substituting a comma in lieu thereof and (ii) inserting new clauses (D) and (E) immediately prior to the second proviso to read as follows:

“, (D) the Borrower may, on or prior to May 16, 2004, repurchase the Warrants issued pursuant to Article XII to the extent that immediately before and after giving effect to such repurchase, Availability is not less than $7,500,000 and no Default or Event of Default shall exist, and (E) the Borrower may pay dividends on its preferred Capital Stock issued in connection with a Permitted Preferred Equity Issuance, provided, that (x) such dividends do not commence until 90 days after the issuance thereof and (y) such dividends may be made in cash so long as (I) no Default or Event of Default shall have occurred and be continuing or would result from the making of any such cash payment, and (II) immediately before and after giving effect to any such payment, Availability is not less than $5,000,000”

(b) The second proviso of Section 7.02(h) of the Financing Agreement is hereby amending by deleting in its entirety the phrase “the Loans and Letter of Credit Obligations exceed the Borrowing Base” and substituting in lieu thereof the following: “the sum of the Revolving A Loans, the Revolving B Loans, the Revolving C Loans and the Letter of Credit Obligations exceeds the Borrowing Base minus the Availability Reserve”.

18. Limitation on Issuance of Capital Stock. The proviso in Section 7.02(l) the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“provided, however, that (i) the Borrower may issue or sell or enter into any agreement or arrangement for the issuance or sale of additional shares of its Capital Stock that is of a class traded on the Effective Date on a national securities exchange in a public offering pursuant to a registration statement that has been or will be filed with, and declared effective by, the SEC (a “Secondary Public Offering”) and (ii) the Borrower may issue or sell or enter into any agreement or arrangement, upon such terms and conditions satisfactory to the Agents, for the issuance or sale of its preferred Capital Stock, pursuant to terms and conditions which shall include, among other things, the provisions set forth in Section 7.02(h) related to the payment of dividends, and such other terms and conditions that are satisfactory to the Agents as determined in their sole discretion, exercised reasonably (a “Permitted Preferred Equity Issuance”)”

19. Reserves. Section 7.02(x) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(x) Reserves. Permit, on April 30, 2004, the Borrower’s Proved Developed Producing Reserves, Proved Developed Non-Producing Reserves and Proved Undeveloped Reserves to contain less than 120 bcfe and the Borrower’s Proved Developed Producing Reserves to contain less than 40 bcfe. On April 30, 2004, the Borrower shall provide satisfactory evidence and certify to the matters described in the immediately preceding sentence.”

-11-

20. Collateral Coverage. Section 7.02(y) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(y) From and after April 30, 2004, permit the sum of (x) the then applicable Borrowing Base and (y) 65% of the UK PV-10 of the Proved Developed Producing Reserves of ATP UK related to the Helvellyn field in the North Sea — UK Sector to be less than an amount equal to 125% of the sum of the aggregate amount of the Revolving Loans and Letter of Credit Obligations.”

21. Total Leverage Ratio. Section 7.03(a) of the Financing Agreement is hereby amended by deleting the ratios for each fiscal period set forth below and substituting in lieu thereof new ratios set forth opposite to each such fiscal period set forth below:

Fiscal Period	Ratio
Twelve month period ended January 31, 2004	3.35 to 1.0
Twelve month period ended February 29, 2004	3.30 to 1.0
Twelve month period ended March 31, 2004	2.90 to 1.0
Twelve month period ended April 30, 2004	2.75 to 1.0

22. Domestic Leverage Ratio. Section 7.03(b) of the Financing Agreement is hereby amended by deleting the ratios for each fiscal period set forth below and substituting in lieu thereof new ratios set forth opposite to each such fiscal period set forth below:

Fiscal Period	Ratio
Twelve month period ended January 31, 2004	3.28 to 1.0
Twelve month period ended February 29, 2004	3.28 to 1.0
Twelve month period ended March 31, 2004	2.90 to 1.0
Twelve month period ended April 30, 2004	2.75 to1 .0

23. Consolidated EBITDA. Section 7.03(e) of the Financing Agreement is hereby amended by deleting the Consolidated EBITDA amounts for each fiscal period set forth below and substituting in lieu thereof new Consolidated EBITDA amounts set forth opposite to each such fiscal period set forth below:

Fiscal Period	Consolidated EBITDA
Four month period ended January 31, 2004	$	7,686,000
Five month period ended February 29, 2004	$	11,809,000
Six month period ended March 31, 2004	$	19,402,000
Seven month period ended April 30, 2004	$	26,660,000

24. Current Ratio. Section 7.03(g) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(g) Permit the ratio of current assets (which shall include an amount equal to the principal amount of Loans available to be borrowed by the Borrower

-12-

under this Agreement, but shall exclude an amount equal to any increase (but not decrease) resulting from the application of FASB 133 and FASB 143) to current liabilities (excluding (i) all Indebtedness and accrued interest expense otherwise included as current liabilities, (ii) an amount equal to any increase (but not decrease) in current liabilities resulting from the application of FASB 133 and FASB 143 and (iii) any accruals for, and payments of (to the extent such payments were not accrued), the Legacy Award) to be, for the end of each fiscal month commencing on October 31, 2003 and through and including December 31, 2004, less than .35 to 1.0, and (z) for the end of each fiscal month commencing on January 31, 2005 and thereafter, less than 1.0 to 1.0 of the Borrower.”

25. Gulf of Mexico Production. Section 7.03 of the Financing Agreement is hereby amended by inserting immediately after clause (g) the following new clause (h):

“(h) Gulf of Mexico Production. Permit the amount of Hydrocarbons produced by, or capable of being produced from, the Oil and Gas Properties of the Borrower located in the Gulf of Mexico (other than production declines as a result of (x) a performance failure by a third party not as a result of any actions or inactions of the Borrower or (y) any acts of God), to be less than 85% of the amount of Hydrocarbons projected to be produced in the Weekly Cash Flow Schedules for each of the months of February 2004, March 2004 and April 2004, to be measured on a cumulative basis.”

26. Events of Default. (a) Section 9.01(c) of the Financing Agreement is hereby amended by (i) deleting the word “and” in subclause (i) and substituting a comma in lieu thereof and (ii) inserting immediately after the reference to clause “(s)” the following “, and (v)”.

(b) Section 9.01(w) of the Financing Agreement is hereby amended and restated in its entirety to read as follows:

“(w) by March 1, 2004, ATP UK, on a daily basis, shall fail to produce Hydrocarbons from the Helvellyn field in the United Kingdom sector of the North Sea in an amount equal to or exceeding 12.5 mcfe of Hydrocarbons;”

27. Issuance of Equity Interests. The following new Article XII shall be added to the Financing Agreement:

“ARTICLE XII

ISSUANCE OF EQUITY INTERESTS

Section 12.01 Authorization and Issuance of Warrants. On February 16, 2004, the Borrower shall issue to the Lenders or their designees one or more warrant certificates covering the purchase of shares of Common Stock of

-13-

the Borrower substantially in a form acceptable to the Agents (such certificates, and all warrant certificates covering such stock issued upon transfer, division or combination of, or in substitution for, any thereof, the “Warrant Agreements” and such rights to purchase Common Stock of the Borrower provided thereby being herein called the “Warrants”) in an amount equal to 750,000 shares of Common Stock of the Borrower (the “Warrant Stock”). It is understood and agreed that the Warrants contain provisions affecting the number of shares of Common Stock of the Borrower that may be acquired, which provisions are set forth in the Warrants. Such Warrants will have an exercise price equal to $6.75 per share and will be exercisable on and after May 17, 2004 and cease to be exercisable on February 16, 2009.

Section 12.02 Securities Act Matters.

(a) Each Warrant Holder represents and warrants to the Borrower that:

(i) it is acquiring the Warrants hereunder for its own account, without a view to the distribution thereof, all without prejudice, however, to the right of any Warrant Holder at any time, in accordance with this Agreement, lawfully to sell or otherwise to dispose of all or any part of the Warrants or Warrant Stock held by it,

(ii) it is an “accredited investor” within the meaning of Regulation D under the Securities Act, and

(iii) it understands that, as of the date of issuance of the Warrants, the Warrants and the Warrant Stock have not been registered under the Securities Act and that they may not be resold unless they are registered under such act or an exemption from registration is available, and the Warrants and the Warrant Shares will contain appropriate restrictive legends to this effect.

(b) The Borrower represents and warrants to each Warrant Holder that:

(i) Assuming the truth and accuracy of each Warrant Holder’s representations and warranties contained in the immediately preceding paragraphs, the issuance of the Warrants to each Warrant Holder hereunder and the issuance of shares of Common Stock to each Warrant Holder pursuant to the Warrants are exempt from the registration and prospectus delivery requirements of the Securities Act, and

(ii) All stock and securities of the Borrower heretofore issued and sold by the Borrower were, and all securities of the Borrower issued

-14-

and sold by the Borrower on and after the date hereof are or will be issued and sold in accordance with, or are or will be exempt from, the registration and prospectus delivery requirements of the Securities Act.

(c) The Borrower agrees that neither it nor any Person acting on its behalf has offered or will offer the Warrants or Warrant Stock or any part thereof or any similar securities for issue or sale to, or has solicited or will solicit any offer to acquire any of the same from, any Person so as to bring the issuance and sale of the Warrants or Warrant Stock hereunder within the provisions of the registration and prospectus delivery requirements of the Securities Act.

Section 12.03 Certain Taxes. The Borrower shall pay all taxes (other than Federal, state or local income taxes) which may be payable in connection with the execution and delivery of this Agreement or the issuance of the Warrants or Warrant Stock hereunder or in connection with any modification of this Agreement or the Warrants and shall hold each Warrant Holder, Lender and Agent harmless without limitation as to time against any and all liabilities with respect to all such taxes. The obligations of the Borrower under this Section 12.03 shall survive any redemption, repurchase or acquisition of Warrants or Warrant Stock by the Borrower, any termination of this Agreement, and any cancellation or termination of the Warrants. The parties hereto agree that for income tax purposes, the aggregate purchase price to be attributed to the Warrants issued to the Warrant Holders hereunder on February 16, 2004 is $750,000.

Section 12.04 Cancellation and Issuance. If any Warrant Holder assigns or otherwise transfers all or any of its Loans (including by selling participations therein) to any Person, each Warrant Holder may request (upon 10 days’ prior notice to the Borrower) that (a) a number of Warrants held by each Warrant Holder be canceled on the date of such assignment and transfer and (b) a like number of Warrants be issued by the Borrower to the Person to whom such Loans are being assigned or otherwise transferred. Upon the date specified in such request:

(i) the Borrower shall issue, and each Warrant Holder shall surrender (or cause to be surrendered) for cancellation, such number of Warrants as aforesaid, provided that such issuance shall not violate the Securities Act or any applicable state securities laws;

(ii) the Borrower will deliver to each Person that receives a certificate for Warrants a favorable legal opinion from counsel to the Borrower acceptable to such Person, covering the matters set forth in the opinion of counsel to the Borrower and its Subsidiaries as may be reasonably requested (to the extent relating to the Warrants);

-15-

(iii) each Person that receives Warrants will deliver a certificate to the Borrower affirming the representations and warranties contained in Section12.02(a) hereof as of such date; and

(iv) the Borrower will deliver a certificate to each Person that receives Warrants affirming the representations and warranties contained in Section 12.02(b) hereof as of such date.”

28. Waiver. (a) Effective as of the Amendment Effective Date (as hereinafter defined), and in reliance upon the representations and warranties of the Borrower and the Guarantors set forth in the Financing Agreement, this Amendment and the other Loan Documents, and in accordance with Section 11.02 of the Financing Agreement, the Lenders hereby consent to, and waive, each of the following Events of Default:

(i) the failure by the Borrower to comply with the minimum ratio of Consolidated Funded Indebtedness to Consolidated EBITDA requirement for the fiscal period ending December 31, 2003 set forth in Section 7.03(a) of the Financing Agreement; and

(ii) the failure by the Borrower to comply with the minimum Consolidated EBITDA requirement for the fiscal period ending December 31, 2003 set forth in Section 7.03(e) of the Financing Agreement.

(b) The consent and waiver of the Events of Default relating to the events set forth in paragraph (a) above (i) shall be effective only in each specific instance set forth herein and for the specific purposes set forth herein, and (ii) does not allow for any other or further departure from the terms and conditions of the Financing Agreement or any other Loan Documents, which terms and conditions shall continue in full force and effect.

29. Conditions to Effectiveness. The effectiveness of this Amendment (the date of such effectiveness, the “Amendment Effective Date”) is subject to the following conditions precedent that:

(a) this Amendment shall have been duly executed by an Authorized Officer of the Borrower and each Guarantor and the Agents and the Lenders and delivered to the Agents;

(b) the Registration Rights Agreement, dated as of the Amendment Effective Date, shall have been duly executed by an Authorized Officer of the Borrower and each of the initial holders of the Warrants (as defined in the Financing Agreement after giving effect to this Amendment), and delivered to the Agents;

(c) each of the Warrant Agreements, dated the Amendment Effective Date, shall have been duly executed by an Authorized Officer of the Borrower and delivered to the Agents;

-16-

(d) after giving effect to this Amendment, each of the representations and warranties made by each Loan Party in or pursuant to the Loan Documents shall be true and correct in all material respects on and as of the Amendment Effective Date as if made on and as of such date (unless such representations and warranties are stated to relate to a specific earlier date, in which case such representations and warranties shall be true and correct in all material respects as of such earlier date);

(e) after giving effect to this Amendment, no Default or Event of Default shall have occurred and be continuing on such date;

(f) the sale by the Borrower of a certain portion of its Proved Reserves to NI Energy Venture Inc. shall have been consummated and the Agents shall be satisfied that the Funding Agent shall have received the proceeds therefrom;

(g) a Borrowing Base Certificate, dated as of the Amendment Effective Date, shall have been duly executed by the Borrower and delivered to the Agents;

(h) all fees and expenses of the Agents and the Lenders (including, without limitation, fees and expenses of counsel) shall be paid in full, it being understood that such fees and expenses may be charged to the Borrower’s Loan Account; and

(i) all other legal matters incident to this Amendment shall be satisfactory to the Agents and their counsel.

30. Post-Closing Deliveries. On or prior to February 23, 2004, the Borrower shall deliver to the Agents an opinion of counsel to the Borrower, in form and substance satisfactory to the Agents, as to such matters related to this Amendment and the issuance of the Warrants and the Warrant Agreements as the Agents may reasonably request.

31. Representations and Warranties. Each of the Loan Parties hereby jointly and severally represents and warrants to the Agents and the Lenders as follows:

(a) Each of the Loan Parties has all requisite power and authority to execute, deliver and perform this Amendment, and to perform the Financing Agreement, as amended hereby, and this Amendment has been duly executed and delivered by each Loan Party.

(b) The execution, delivery and performance of this Amendment by each of the Loan Parties, and the performance by each of the Loan Parties of the Financing Agreement, as amended hereby, (i) have been duly authorized by all necessary action, (ii) do not and will not contravene its charter or by-laws, its limited liability company or operating agreement or its certificate of partnership or partnership agreement, as applicable, or any applicable law or any contractual restriction binding on or otherwise affecting it or any of its properties, (iii) do not and will not result in or require the creation of any Lien (other than pursuant to any Loan Document) upon or with respect to any of its material properties, and (iv) do not and will not result in any material default, noncompliance, suspension, revocation,

-17-

impairment, forfeiture or nonrenewal of any material permit, license, authorization or approval applicable to its operations or any of its properties.

(c) No authorization or approval or other action by, and no notice to or filing with, any Governmental Authority is required in connection with the due execution, delivery and performance by any Loan Party of this Amendment or the performance by any Loan Party of the Financing Agreement, as amended hereby.

(d) This Amendment and the Financing Agreement, as amended hereby, constitute the legal, valid and binding obligations of each Loan Party, enforceable against such Persons in accordance with their terms, except as may be limited by applicable bankruptcy, insolvency, reorganization, moratorium or other similar laws.

32. Ratification. Except as otherwise expressly provided herein, each Loan Party confirms and agrees that (a) each Loan Document to which it is a party is, and shall continue to be, in full force and effect and is hereby ratified and confirmed in all respects except that on and after the date on which this Amendment is effective all references in any such Loan Document to “the Financing Agreement”, “thereto”, “thereof”, “thereunder”, or words of like import referring to the Financing Agreement shall mean the Financing Agreement as amended by this Amendment, and (b) to the extent that any such Loan Document purports to assign or pledge to the Administrative Agent, or to grant to the Administrative Agent a security interest in or lien on, any collateral as security for its obligations from time to time existing in respect of the Loan Documents, such pledge, assignment and/or grant of a security interest or lien is hereby ratified and confirmed in all respects as security for all of its obligations, whether now existing or hereafter arising. This Amendment does not and shall not affect any Obligation or Guarantee Obligation (as the case may be), other than as expressly provided herein, of any Loan Party under or arising from the Financing Agreement or any other Loan Document, all of which obligations are hereby ratified and shall remain in full force and effect. Except as expressly provided herein, the execution, delivery and effectiveness of this Amendment shall not operate as a waiver of any right, power or remedy of the Agents or the Lenders under the Financing Agreement or any other Loan Document, nor constitute a waiver of any provision of the Financing Agreement or any other Loan Document.

-18-

33. Expenses. The Borrower hereby agrees to pay to the Agents upon demand the amount of any and all fees, costs and expenses, including the reasonable fees, disbursements and other client charges of the Agents’ counsel, which the Agents may incur in connection with this Amendment, the amounts of which the Borrower agrees may be charged to the Loan Account.

34. Counterparts. This Amendment may be executed in any number of counterparts and by the different parties hereto in separate counterparts, each of which shall be deemed to be an original, but all of which taken together shall constitute one and the same waiver. Delivery of an executed counterpart of this Amendment by telecopier shall be equally as effective as delivery of an original executed counterpart of this Amendment.

35. Governing Law. This Amendment shall be governed by and construed in accordance with the law of the State of New York applicable to contracts made and to be performed within such state.

-19-

IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed and delivered by their duly authorized officers as of the date first above written.

AGENTS AND LENDERS:
ABLECO FINANCE LLC,as Collateral Agent, Administrative Agent and Lender, for itself as a Lender and on behalf of its affiliate assigns as Lenders
By:	/s/    KEVIN GENDA
Title:	Senior Vice President
WELLS FARGO FOOTHILL, INC., as Funding Agent and Lender
By:	/s/    DREW STAWIN
Title:	Senior Vice President
BORROWER:
ATP OIL & GAS CORPORATION
By:	/s/    T. PAUL BULMAHN
Title:	President
GUARANTOR:
ATP ENERGY, INC.
By:	/s/    T. PAUL BULMAHN
Title:	President
ATP OIL & GAS (UK) LIMITED
By:	/s/    T. PAUL BULMAHN
Title:	Director

EX-99.1

News Release

For Immediate Release

Company contacts:

T. Paul Bulmahn, Chairman and President

Albert L. Reese Jr., SVP and Chief Financial Officer

713-622-3311

ATP Oil & Gas Corporation Amends Senior Credit Facility

HOUSTON – February 27, 2004 – (PRNewswire) – ATP Oil & Gas Corporation (NASDAQ: ATPG) today announced an amendment to its $125 million senior credit facility. As announced in our quarterly report on Form 10-Q for the period ended September 30, 2003, we executed an amendment in November 2003 to our credit agreement that, among other things, contemplated a new $15 million Tranche to be secured by our North Sea oil and gas properties in addition to our U.S. properties. On December 3, 2003, we executed a second amendment to our credit agreement, which implemented the $15 million UK Tranche, with a maturity date of February 16, 2004, implemented a borrowing base coverage test of 150% commencing February 16, 2004, modified several of the financial covenants contained in the credit agreement and added new reporting and compliance covenants and events of default under the credit agreement. We incurred fees of approximately $750,000 in connection with the execution of the second amendment, half of which were paid on December 3, 2003 with the remainder paid February 16, 2004.

On February 23, 2004 we finalized the conditions subsequent to the third amendment to the credit agreement which is effective as of February 16, 2004. The third amendment extended the maturity of the UK Tranche to January 31, 2005, reduced the borrowing base coverage test from 150% of the amounts outstanding under our credit facility to 125%, extended the measuring date for such test from February 16, 2004 to April 30, 2004, imposed a new borrowing base reserve of $14 million at April 30, 2004 and provided waivers for non-compliance with certain financial covenants as of December 31, 2003. In order to satisfy this additional reserve requirement, remain in compliance with our existing credit facility and meet our capital expenditure needs, we expect to require approximately $30 million in additional financing before the end of the first quarter 2004. As consideration for the execution of the third amendment, we issued warrants which we may repurchase under certain conditions to our lenders to purchase 750,000 shares of our common stock, exercisable at a price of $6.75 per share.

For additional information regarding the amendments, please refer to the Form 8-K filed as of this date.

ATP Oil & Gas Corporation 4600 Post Oak Place Suite 200 Houston, TX 77027

1

About ATP Oil & Gas Corporation

ATP Oil & Gas is a development and production company of natural gas and oil in the Gulf of Mexico and the North Sea. The company trades publicly as ATPG on the NASDAQ National Market.

Forward-looking Statements

Certain statements included in this news release are “forward-looking statements” under the Private Securities Litigation Reform Act of 1995. ATP cautions that assumptions, expectations, projections, intentions, or beliefs about future events may, and often do, vary from actual results and the differences can be material. Some of the key factors which could cause actual results to vary from those ATP expects include changes in natural gas and oil prices, the timing of planned capital expenditures, availability of acquisitions, uncertainties in estimating proved reserves and forecasting production results, operational factors affecting the commencement or maintenance of producing wells, the condition of the capital markets generally, as well as our ability to access them, and uncertainties regarding environmental regulations or litigation and other legal or regulatory developments affecting our business. More information about the risks and uncertainties relating to ATP’s forward-looking statements are found in our SEC filings

# # #

ATP Oil & Gas Corporation 4600 Post Oak Place Suite 200 Houston, TX 77027

2