SC 13D/A

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D
Under the Securities Exchange Act of 1934
(Amendment No. 2)*

Brigham Exploration Company (Name of Issuer)

Common Stock, $0.01 par value per share (Title of Class of Securities)

109178 10 3 (CUSIP Number)

Benjamin A. Silbert
Credit Suisse First Boston
11 Madison Avenue
New York, New York 10010
(212) 538-1453 (Name, Address and Telephone Number of Person Authorized
to Receive Notices and Communications)

December 20, 2002 (Date of Event which Requires Filing of this Statement)

        If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §240.13d-1(e), §240.13d-1(f) or §240.13d-1(g), check the following box    o.

        NOTE: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7(b) for other parties to whom copies are to be sent.

        *The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

        The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

(Continued on following page(s))
Page 1 of 11 Pages

CUSIP No.    109178 10 3 SCHEDULE 13D Page 2 of 11 Pages

(1)	NAMES OF REPORTING PERSONS. S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Credit Suisse First Boston, on behalf of the Credit Suisse First Boston Business Unit
(2)	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*			(a)  o
				(b)  o
(3)	SEC USE ONLY
(4)	SOURCE OF FUNDS* N/A
(5)	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)
				o
(6)	CITIZENSHIP OR PLACE OF ORGANIZATION Switzerland
NUMBER OF SHARES		(7)	SOLE VOTING POWER See Item 5
BENEFICIALLY
OWNED BY EACH REPORTING		(8)	SHARED VOTING POWER See Item 5
PERSON WITH
		(9)	SOLE DISPOSITIVE POWER See Item 5
		(10)	SHARED DISPOSITIVE POWER See Item 5
(11)	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON See Item 5
(12)	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*
				o
(13)	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) See Item 5
(14)	TYPE OF REPORTING PERSON* BK, HC, OO
*SEE INSTRUCTIONS BEFORE FILLING OUT! INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7 (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION.

CUSIP No.    109178 10 3 SCHEDULE 13D Page 3 of 11 Pages

Item 1. Security and Issuer.

        This Amendment No. 2 to Schedule 13D is filed by the undersigned to amend and supplement the Schedule 13D, filed on January 10, 2001 (the "Original 13D"), and the Amendment No. 1 to Schedule 13D, filed on April 9, 2001 (the "Amendment No. 1"). The Original 13D related to the common stock, $0.01 par value per share (the "Common Stock"), of Brigham Exploration Company, a Delaware corporation (the "Company"), that may be acquired upon exercise of warrants (the "November 2000 Warrants") to purchase 6,666,667 shares of Common Stock (the "November 2000 Warrant Shares"), and the Amendment No. 1 related to the acquisition of additional warrants (the "March 2001 Warrants") to purchase 2,105,263 shares of Common Stock (the "March 2001 Warrant Shares"). This Amendment No. 2 reports the acquisition of additional warrants (the "December 2002 Warrants," and together with the November 2000 Warrants and the March 2001 Warrants, the "Warrants") to purchase 2,298,850 shares of Common Stock (the "December 2002 Warrant Shares," and together with the November 2000 Warrant Shares and the March 2001 Warrant Shares, the "Warrant Shares") and 2,564,102 shares of Common Stock (the "December 2002 Common Shares"). The principal executive offices of the Company are at 6300 Bridge Point Parkway, Building 2, Suite 500, Austin, Texas 78730. Capitalized terms used herein and not otherwise defined shall have the meanings set forth in the Original 13D.

Item 2. Identity and Background.

        Item 2(a)-(c) & (f) is hereby amended and restated in its entirety as follows:

        "(a)-(c) & (f) This Statement is being filed by Credit Suisse First Boston, a Swiss bank (the "Bank"), on behalf of itself and its subsidiaries, to the extent that they constitute part of the Credit Suisse First Boston business unit (the "CSFB Business Unit" or the "Reporting Person"). The CSFB Business Unit is engaged in the corporate and investment banking, trading (equity, fixed income and foreign exchange), private equity investment and derivatives businesses on a worldwide basis. The Bank's registered head office is located at Uetlibergstrasse 231, P.O. Box 900, CH-8045 Zurich, Switzerland. The Bank and its subsidiaries engage in other separately managed activities, most of which constitute the independently operated Credit Suisse Asset Management business unit; the Credit Suisse Asset Management business unit provides asset management and investment advisory services to institutional investors worldwide.

        The Bank owns directly a majority of the voting stock, and all of the non-voting stock, of Credit Suisse First Boston, Inc., a Delaware corporation ("CSFBI"). The ultimate parent company of the Bank and CSFBI, and the direct owner of the remainder of the voting stock of CSFBI, is Credit Suisse Group, a corporation formed under the laws of Switzerland ("CSG").

CUSIP No.    109178 10 3 SCHEDULE 13D Page 4 of 11 Pages

        As of November 3, 2000, CSFBI acquired all of the voting stock of Donaldson, Lufkin & Jenrette, Inc., a Delaware corporation, which was renamed Credit Suisse First Boston (USA), Inc. ("CSFB-USA"), and the following entities became indirect subsidiaries of CSFBI: (1) DLJMB Funding III, Inc., a Delaware corporation ("Funding III"); (2) DLJ ESC II, L.P., a Delaware limited partnership ("ESC II"); (3) DLJ LBO Plans Management Corporation, a Delaware corporation ("LBO"); (4) DLJ Merchant Banking Partners III, L.P., a Delaware limited partnership ("MBP"); (5) DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III, C.V., a Netherlands Antilles limited partnership ("DOP"); (6) DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-1, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-1, C.V., a Netherlands Antilles limited partnership ("DOP-1"); (7) DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-2, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-2, C.V., a Netherlands Antilles limited partnership ("DOP-2"); (8) DLJ Merchant Banking III, Inc., a Delaware corporation ("MBIII Inc."); (9) DLJ MB PartnersIII GmbH & Co. KG, a German limited partnership ("MBP GmbH"); (10) Millenium Partners II, L.P., a Delaware limited partnership ("MPII"); (11) MBP III Plan Investors, L.P., a Delaware limited partnership ("MPIII"); and (12) DLJ Capital Investors, Inc., a Delaware corporation ("DLJCI" and together with the entities listed in (1) through (11) above the "DLJ Entities").

        Funding III is a Delaware corporation that makes investments for long-term appreciation. Funding III is a wholly owned subsidiary of DLJCI.

        ESC II is a Delaware limited partnership and "employee securities company" as defined in the Investment Company Act of 1940, as amended.

        LBO is a Delaware corporation and a registered investment advisor. LBO is a wholly owned subsidiary of DLJCI. As the Managing General Partner of ESC II and MPIII, LBO is responsible for the day-to-day management of these entities and makes the investment decisions on behalf these entities.

        MBP is a Delaware limited partnership that makes investments for long-term appreciation. MBP is the Managing Limited Partner of MBP GmbH and is responsible for the day-to-day management of this entity and makes the investment decisions on behalf of this entity.

        DOP, DOP-1 and DOP-2 are Netherlands Antilles limited partnerships that make investments for long-term appreciation.

        MBIII Inc. is a Delaware corporation and a registered investment adviser. MBIII Inc. is the Managing General Partner of MBP and MPII and the Advisory General Partner for DOP, DOP-1 and DOP-2. MBIII Inc. is responsible for the management of these entities and makes the investment decisions on behalf of these entities. MBIII Inc. is a wholly owned subsidiary of DLJCI.

CUSIP No.    109178 10 3 SCHEDULE 13D Page 5 of 11 Pages

        MBP GmbH is a German limited partnership that makes investments for long-term appreciation.

        MPII and MPIII are Delaware limited partnerships that make investments for long-term appreciation.

        DLJCI is a Delaware corporation and a holding company. DLJCI is a wholly owned subsidiary of CSFB-USA.

        CSFB-USA directly owns all of the capital stock of DLJCI. CSFB-USA, acting on its own behalf or through its subsidiaries, is a registered broker/dealer and registered investment advisor engaged in investment banking, institutional trading and research, investment management and financial and correspondent brokerage services.

        The principal business of CSG is acting as a holding company for a global financial services group with five distinct specialized business units that are independently operated. In addition to the two business units referred to above, CSG and its subsidiaries (other than the Bank and its subsidiaries) are comprised of (a) the Credit Suisse Private Banking business unit that engages in global private banking business, (b) the Credit Suisse business unit that engages in the Swiss domestic banking business and (c) the Winterthur business unit that engages in the global insurance business. CSG's principal business address is: Paradeplatz 8, Postfach 1, CH-8070, Zurich, Switzerland.

        CSG, for purposes of certain federal securities laws, may be deemed ultimately to control the Bank and the CSFB Business Unit. CSG, its executive officers and directors, and its direct and indirect subsidiaries (including all of the business units except the CSFB Business Unit), may beneficially own the Warrants, the Warrant Shares and the December 2002 Common Shares, and such Warrant Shares and December 2002 Common Shares are not reported in this Statement. Due to the separate management and independent operation of its business units, CSG disclaims beneficial ownership of the Warrants, the Warrant Shares and the December 2002 Common Shares beneficially owned by its direct and indirect subsidiaries, including the Reporting Person. The Reporting Person disclaims beneficial ownership of shares of Common Stock beneficially owned by CSG and any of CSG's and the Bank's other business units.

        The address of the principal business and office of CSFBI is 11 Madison Avenue, New York, New York 10010. The address of the principal business and office of each of the DLJ Entities is 277 Park Avenue, New York, New York 10172. The name, business address, citizenship, present principal occupation or employment and the name and business address of any corporation or organization in which each such employment is conducted, of each executive officer or director of the Reporting Person, CSFBI, CSFB-USA and those DLJ Entities that are corporations are set forth on Schedules A through G, respectively, attached hereto, each of which is incorporated by reference herein."

CUSIP No.    109178 10 3 SCHEDULE 13D Page 6 of 11 Pages

Item 3. Source and Amount of Funds or Other Consideration.

        Item 3 is hereby amended and restated in its entirety as follows:

        "The purchase price for the purchase of the November 2000 Warrants was funded through internally generated funds of Funding III and ESC II. The purchase price for the purchase of the March 2001 Warrants was funded through a combination of capital contributions from limited partners and internally generated funds of Funding III, ESC II, MBP and DOP. The purchase price for the purchase of the December 2002 Warrants and the December 2002 Common Shares was funded through a combination of capital contributions from limited partners and internally generated funds of MBP, DOP, DOP-1, DOP-2, MBP GmbH, MPII and MPIII."

Item 4. Purpose of Transaction.

        Item 4 is hereby amended and restated in its entirety as follows:

        "Of the November 2000 Warrants, Funding III purchased from the Company warrants to purchase 6,036,667 shares of Common Stock and ESC II purchased from the Company warrants to purchase 630,000 shares of Common Stock, both pursuant to a Securities Purchase Agreement dated November 1, 2000 by and among the Company, Funding III and ESC II (the "November 2000 Securities Purchase Agreement"). The November 2000 Warrants are immediately exercisable at a price of $3.00 per share (the "November 2000 Exercise Price") and expire on November 1, 2010.

        Of the March 2001 Warrants, Funding III purchased from the Company warrants to purchase 141,869 shares of Common Stock, ESC II purchased from the Company warrants to purchase 371,789 shares of Common Stock, MBP purchased from the Company warrants to purchase 1,527,154 shares of Common Stock, and DOP purchased from the Company warrants to purchase 64,451 shares of Common Stock, pursuant to a Securities Purchase Agreement dated March 5, 2001 by and among the Company, Funding III, ESC II, MBP and DOP (the "March 2001 Securities Purchase Agreement"). The March 2001 Warrants became exercisable after stockholder approval was received at the annual stockholders meeting on May 10, 2001. The March 2001 Warrants are exercisable at a price of $4.75 per share (the "March 2001 Exercise Price") and expire on March 5, 2011.

CUSIP No.    109178 10 3 SCHEDULE 13D Page 7 of 11 Pages

        Of the December 2002 Warrants, MBP purchased from the Company warrants to purchase 1,657,241 shares of Common Stock, DOP purchased from the Company warrants to purchase 90,262 shares of Common Stock, DOP-1 purchased from the Company warrants to purchase 30,211 shares of Common Stock, DOP-2 purchased from the Company warrants to purchase 21,522 shares of Common Stock, MBP GmbH purchased from the Company warrants to purchase 14,280 shares of Common Stock, MPII purchased from the Company warrants to purchase 2,878 shares of Common Stock, and MPIII purchased from the Company warrants to purchase 482,456 shares of Common Stock, pursuant to a Securities Purchase Agreement dated December 20, 2002 by and among the Company, MBP, DOP, DOP-1, DOP-2, MBP GmbH, MPII and MPIII (the "December 2002 Securities Purchase Agreement," and together with the November 2000 Securities Purchase Agreement and the March 2001 Securities Purchase Agreement, the "Securities Purchase Agreements"). The December 2002 Warrants are exercisable as of June 20, 2003 at a price of $4.35 per share (the "December 2002 Exercise Price," and together with the November 2000 Exercise Price and the March 2001 Exercise Price, the "Exercise Price") and expire December 20, 2012.

        The November 2000 Exercise Price and the March 2001 Exercise Price may be paid in cash or by the delivery of shares of Series A Preferred Stock of the Company, par value $0.01 per share ("Series A Preferred Stock"), issued and sold to Funding III, ESC II, MBP and DOP (as described below) based on 100% of the stated value of such shares, plus accrued dividends thereon. The December 2002 Exercise Price may be paid in cash or by the delivery of Series B Preferred Stock of the Company, par value $0.01 per share ("Series B Preferred Stock"), issued and sold to MBP, DOP, DOP-1, DOP-2, MBP GmbH, MPII and MPIII (as described below) based on 100% of the stated value of such shares, plus accrued dividends thereon. In addition, the November 2000 Warrants must be exercised upon the written request by the Company if the reported trading price per share of Common Stock exceeds $5.00 per share for sixty consecutive trading days, the March 2001 Warrants must be exercised upon the written request by the Company if the reported trading price per share of Common Stock exceeds $7.125 per share for sixty consecutive trading days, and the December 2002 Warrants must be exercised upon the written request by the Company if the reported trading price per share of Common Stock exceeds $6.375 per share for sixty consecutive trading days.

        The Exercise Price and number of shares of Common Stock purchasable upon exercise of the Warrants are subject to ordinary and customary anti-dilution adjustments in the case of mergers, consolidations, reclassifications, stock splits or dividend distributions in the form of securities of the Company. The Exercise Price is also subject to an anti-dilution adjustment on a weighted-average basis for the issuance of additional shares of Common Stock or securities that are exercisable for or convertible into Common Stock, other than options granted under employee benefit plans ("Common Stock Equivalents"), at a price per share that is less than the average of the high and low trading price per share of Common Stock for the twenty days immediately preceding the date such issuance was authorized by the board of directors of the Company (the "Market Price").

CUSIP No.    109178 10 3 SCHEDULE 13D Page 8 of 11 Pages

        Notwithstanding the preceding sentence, until March 5, 2003 for the March 2001 Warrants or until December 20, 2004 for the December 2002 Warrants, if the Company issues (i) additional shares of Common Stock at a price per share less than the then current March 2001 Exercise Price or December 2002 Exercise Price, then the March 2001 Exercise Price and/or December 2002 Exercise Price then in effect shall be adjusted to equal the price per share of such newly-issued shares of Common Stock, and (ii) Common Stock Equivalents having an exercise or conversion price that is less than the then current March 2001 Exercise Price and/or December 2002 Exercise Price, then the March 2001 Exercise Price and/or December 2002 Exercise Price then in effect shall be adjusted to equal the exercise or conversion price per share of such newly-issued Common Stock Equivalent. In addition, if an adjustment is made to the March 2001 Exercise Price and/or December 2002 Exercise Price as a result of the issuance of additional shares of Common Stock or Common Stock Equivalents, then the number of shares of Common Stock that may be acquired upon exercise of the March 2001 Warrants and/or December 2002 Warrants shall also be adjusted to a number of shares equal to (i) the number of shares of Common Stock that may be acquired upon exercise of the March 2001 Warrants or December 2002 Warrants immediately prior to such issuance, multiplied by (ii) a fraction, the numerator of which is the March 2001 Exercise Price or the December 2002 Exercise Price immediately prior to such issuance, and the denominator of which is the March 2001 Exercise Price or December 2002 Exercise Price immediately after such issuance. In accordance with the provisions described in this paragraph, because the December 2002 Exercise Price is lower than the March 2001 Exercise Price, the Company and the holders of the March 2001 Warrants have agreed to adjust the March 2001 Exercise Price to $4.35 per share but not adjust the number of shares of Common Stock that may be acquired upon exercise of the March 2001 Warrants.

        No adjustments shall be made to the Exercise Price upon the issuance of additional shares of Common Stock pursuant to (i) the exercise of warrants or options outstanding as of the date the Warrants were issued, (ii) the exercise of options granted under a employee benefit plan having a strike price that is not less than the lesser of Market Price or the fair market value per share as determined under the plan, or (iii) a public offering by the Company.

        Pursuant to the terms of the November 2000 Securities Purchase Agreement, simultaneous with their acquisitions of the November 2000 Warrants, Funding III purchased 905,500 shares of Series A Preferred Stock and ESC II purchased 94,500 shares of Series A Preferred Stock. Pursuant to the March 2001 Securities Purchase Agreement, simultaneous with their acquisitions of the March 2001 Warrants, Funding III purchased 33,694 shares of Series A Preferred Stock, ESC II purchased 88,300 shares of Series A Preferred Stock, MBP purchased 362,699 shares of Series A Preferred Stock, and DOP purchased 15,307 shares of Series A Preferred Stock. Dividends accrue on the Series A Preferred Stock at a rate of six percent per annum of the stated value of $20.00 per share, which dividends may be paid in cash or in-kind. If dividends are paid in kind, the dividend rate shall increase to 8% per annum. The shares of Series A Preferred Stock are senior in right of dividends and liquidation to the Common Stock and are not convertible into Common Stock. The Company may, at its option, redeem the Series A Preferred Stock at any time at 101% of its stated value. The Series A Preferred Stock is also mandatorily redeemable on November 1, 2010.

CUSIP No.    109178 10 3 SCHEDULE 13D Page 9 of 11 Pages

        Pursuant to the December 2002 Securities Purchase Agreement, simultaneous with their acquisitions of the December 2002 Warrants, MBP purchased 360,450 shares of Series B Preferred Stock, DOP purchased 19,632 shares of Series B Preferred Stock, DOP-1 purchased 6,571 shares of Series B Preferred Stock, DOP-2 purchased 4,681 shares of Series B Preferred Stock, MBP GmbH purchased 3,106 shares of Series B Preferred Stock, MPII purchased 626 shares of Series B Preferred Stock, and MPIII purchased 104,934 shares of Series B Preferred Stock. Dividends accrue on the Series B Preferred Stock at a rate of six percent per annum of the stated value of $20.00 per share, which dividends may be paid in cash or in-kind. If dividends are paid in kind, the dividend rate shall increase to 8% per annum. The shares of Series B Preferred Stock rank on parity with the Series A Preferred Stock, are senior in right of dividends and liquidation to the Common Stock and are not convertible into Common Stock. After December 20, 2007, the Company may, at its option, redeem the Series A Preferred Stock at 101% of its stated value. The Series B Preferred Stock is also mandatorily redeemable on November 1, 2012.

        Under the terms of the December 2002 Securities Purchase Agreement, MBP, DOP, DOP-1, DOP-2, MBP GmbH, MPII and MPIII have agreed not to acquire any additional shares of voting securities of the Company prior to December 20, 2003, without the consent of the board of directors of the Company.

        The December 2002 Common Shares were acquired pursuant to an Omnibus Agreement dated December 20, 2002 between the Company, MBP, DOP, DOP-1, DOP-2, MBP GmbH, MPII and MPIII (the "Omnibus Agreement"). Pursuant to the Omnibus Agreement, each of MBP, DOP, DOP-1, DOP-2, MBP GmbH, MPII and MPIII converted senior convertible debt acquired from Shell Capital Inc. the same day into an aggregate of 2,564,102 shares of Common Stock. Of the December 2002 Common Shares, MBP owns 1,848,463 shares of Common Stock, DOP owns 100,675 shares of Common Stock, DOP-1 owns 33,699 shares of Common Stock, DOP-2 owns 24,005 shares of Common Stock, MBP GmbH owned 15,926 shares of Common Stock, MPII owns 3,210 shares of Common Stock, and MPIII owns 538,124 shares of Common Stock.

        Funding III and ESC II acquired their respective November 2000 Warrants and March 2001 Warrants for general investment purposes. MBP and DOP acquired their respective November 2000 Warrants, March 2001 Warrants, December 2002 Warrants and December 2002 Common Shares for general investment purposes. DOP-1, DOP-2, MBP GmbH, MPII and MPIII acquired their respective December 2002 Warrants and December 2002 Common Shares for general investment purposes. Funding III, ESC II, MBP, DOP, DOP-1, DOP-2, MBP GmbH, MPII and MPIII reserve the right to change their respective business intent. Subject to the agreements discussed herein, in the Original 13D or in the Amendment No. 1 or attached hereto, to the Original 13D or to the Amendment No. 1, and to market conditions and other factors, any of Funding III, ESC II, MBP, DOP, DOP-1, DOP-2, MBP GmbH, MPII, MPIII or other affiliates of CSFB-USA may acquire or dispose of shares of Common Stock from time to time in the future. Any of Funding III, ESC II, MBP, DOP, DOP-1, DOP-2, MBP GmbH, MPII or MPIII may enter into agreements with third parties relating to acquisitions of shares of Common Stock, or open market, privately negotiated or other transactions and may enter into agreements with management of the Company relating to acquisitions of shares of Common Stock by members of management, issuances of options to management or may affect other similar agreements or transactions. Except as set forth herein, none of Funding III, ESC II, MBP, DOP, DOP-1, DOP-2, MBP GmbH, MPII or MPIII has any plan or proposals which relate to or would result in any of the transactions described in subparagraphs (a) through (j) of Item 4 of Schedule 13D."

CUSIP No.    109178 10 3 SCHEDULE 13D Page 10 of 11 Pages

Item 5. Interest in Securities of the Issuer.

        Item 5 is hereby amended and restated in its entirety as follows:

        "(a)-(b) As of the date of this Amendment No. 2 to Schedule 13D, Funding III directly holds Warrants convertible into 6,178,536 shares of Common Stock and has the shared power to vote and direct the disposition of such Warrants in accordance with the relationships described in Item 2.

        As of the date of this Amendment No. 2 to Schedule 13D, ESC II directly holds Warrants convertible into 1,001,789 shares of Common Stock and has the shared power to vote and direct the disposition of such Warrants in accordance with the relationships described in Item 2.

        As of the date of this Amendment No. 2 to Schedule 13D, MBP directly holds 1,848,463 shares of Common Stock and Warrants convertible into 3,184,395 shares of Common Stock and has the shared power to vote and direct the disposition of such shares and Warrants in accordance with the relationships described in Item 2.

        As of the date of this Amendment No. 2 to Schedule 13D, DOP directly holds 100,675 shares of Common Stock and Warrants convertible into 154,713 shares of Common Stock and has the shared power to vote and direct the disposition of such shares and Warrants in accordance with the relationships described in Item 2.

        As of the date of this Amendment No. 2 to Schedule 13D, DOP-1 directly holds 33,699 shares of Common Stock and Warrants convertible into 30,211 shares of Common Stock and has the shared power to vote and direct the disposition of such shares and Warrants in accordance with the relationships described in Item 2.

        As of the date of this Amendment No. 2 to Schedule 13D, DOP-2 directly holds 24,005 shares of Common Stock and Warrants convertible into 21,522 shares of Common Stock and has the shared power to vote and direct the disposition of such shares and Warrants in accordance with the relationships described in Item 2.

        As of the date of this Amendment No. 2 to Schedule 13D, MBP GmbH directly holds 15,926 shares of Common Stock and Warrants convertible into 14,280 shares of Common Stock and has the shared power to vote and direct the disposition of such shares and Warrants in accordance with the relationships described in Item 2.

        As of the date of this Amendment No. 2 to Schedule 13D, MPII directly holds 3,210 shares of Common Stock and Warrants convertible into 2,878 shares of Common Stock and has the shared power to vote and direct the disposition of such shares and Warrants in accordance with the relationships described in Item 2.

CUSIP No.    109178 10 3 SCHEDULE 13D Page 11 of 11 Pages

        As of the date of this Amendment No. 2 to Schedule 13D, MBIII directly holds 538,124 shares of Common Stock and Warrants convertible into 482,456 shares of Common Stock and has the shared power to vote and direct the disposition of such shares and Warrants in accordance with the relationships described in Item 2.

        As a result of the holdings of the Company's securities described above, the Reporting Person may be deemed to beneficially own indirectly 13,634,882 shares of Common Stock, representing 45.1% of the outstanding shares of Common Stock."

Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer.

        Unchanged.

Item 7. Material to be Filed as Exhibits.

Exhibit 1	Securities Purchase Agreement, dated December 20, 2002
Exhibit 2	Warrant Certificate No. 1 representing rights to purchase 1,657,241 shares of Common Stock (Warrant Certificate No. 2, representing rights to purchase 90,262 shares of Common Stock, Warrant Certificate No. 3, representing rights to purchase 30,211 shares of Common Stock, Warrant Certificate No. 4, representing rights to purchase 21,522 shares of Common Stock, Warrant Certificate No. 5, representing rights to purchase 14,280 shares of Common Stock, Warrant Certificate No. 6, representing rights to purchase 2,878 shares of Common Stock, Warrant Certificate No. 7, representing rights to purchase 482,456 shares of Common Stock, are substantially in the same form as Warrant Certificate No. 1)
Exhibit 3	Second Amendment to Registration Rights Agreement, dated December 20, 2002
Exhibit 4	Omnibus Agreement, dated December 20, 2002

        After reasonable inquiry and to the best of the undersigned's knowledge and belief, the undersigned certifies that the information set forth in this statement is true, complete and correct.

January 7, 2003	CREDIT SUISSE FIRST BOSTON, ON BEHALF OF THE CREDIT SUISSE FIRST BOSTON BUSINESS UNIT
	By:	/s/ Ivy Dodes
	Name: Ivy Dodes Title:  Managing Director

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Item 1. Security and Issuer.
Item 2. Identity and Background.
Item 3. Source and Amount of Funds or Other Consideration.
Item 4. Purpose of Transaction.
Item 5. Interest in Securities of the Issuer.
Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer.
Item 7. Material to be Filed as Exhibits.

EX-1

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EXHIBIT 1

SECURITIES PURCHASE AGREEMENT

        This SECURITIES PURCHASE AGREEMENT (this "Agreement"), is entered into as of December 20, 2002, between Brigham Exploration Company, a Delaware corporation (the "Company"), and the Credit Suisse First Boston entities listed on Schedule A hereto (collectively referred to as "Investors").

        WHEREAS, the Company has authorized the sale and issuance of an aggregate of up to 500,000, shares of its Series B Preferred Stock (the "Shares") and warrants to acquire 2,298,850 shares of its Common Stock, (the "Warrants"), in the form attached hereto as Exhibit A;

        WHEREAS, Investors desire to purchase the Shares and the Warrants on the terms and conditions set forth herein; and

        WHEREAS, the Company desires to issue and sell the Shares and the Warrants to Investors on the terms and conditions set forth herein;

        NOW, THEREFORE, in consideration of the premises and the mutual covenants and agreements herein contained, and intending to be legally bound hereby, the Company and Investors hereby agree as follows:

ARTICLE I
TERMS OF THE TRANSACTION

        1.1    Authorization of Shares.    On or prior to the Closing (as defined in Section 2.1 below), the Company shall have authorized (a) the sale and issuance to Investors of the Shares and the Warrants and (b) the issuance of such shares of Common Stock to be issued upon exercise of the Warrants (the "Warrant Shares"). The Shares shall have the rights, preferences, privileges and restrictions set forth in the Certificate of Designations of the Company, in the form attached hereto as Exhibit B as amended by the Certificate of Amendment of Certificate of Designations in the form attached hereto as Exhibit C (as so amended, the "Certificate of Designations").

        1.2    Sale and Purchase.    Subject to the terms and conditions hereof, at the Closing the Company hereby agrees to issue and sell to Investors, and Investors agree to purchase from the Company, 500,000 Units at a purchase price of Twenty Dollars ($20.00) per Unit, with each such Unit consisting of (i) one Share and (ii) Warrants to purchase 4.5977 Warrant Shares and such Shares and Warrants shall be allocated among the Investors as set forth on Schedule A hereto.

ARTICLE II
CLOSING

        2.1    Closing.    The closing of the sale and purchase of the Shares and Warrants under this Agreement (the "Closing") shall take place at the offices of Brigham Exploration Company, 6300 Bridge Point Parkway, Building 2, Suite 500, Austin, Texas 78730, at 10:00 a.m., local time, on the date of this Agreement or at such other time or place as the Company and Investors may mutually agree (the "Closing Date"). All closing transactions at the Closing shall be deemed to have occurred simultaneously.

Exh. 1-1

ARTICLE III
REPRESENTATIONS AND WARRANTIES OF THE COMPANY

        The Company represents and warrants to Investors, as of the date hereof, that:

        3.1    Corporate Organization.    The Company is a corporation duly organized, validly existing, and in good standing under the laws of the State of Delaware and has all requisite corporate power and authority in all material respects to own, lease, and operate its properties and to carry on its business as now being conducted. No actions or proceedings to dissolve the Company are pending or, to the best knowledge of the Company, threatened. The Company is duly qualified to do business as a foreign corporation and is in good standing in each jurisdiction where such qualification is necessary, except where the failure to so qualify or to be in good standing would not reasonably be expected to have a Material Adverse Effect.

        3.2    Capitalization of the Company.

        (a)  On the Closing Date, the authorized capital stock of the Company will consist of 50,000,000 shares of Common Stock and 10,000,000 shares of preferred stock, $.01 par value, 2,250,000 of which are designated as Series A Preferred Stock and 1,000,000 of which are designated as Series B Preferred Stock. As of the date hereof, (i) 16,302,857 shares of Common Stock are outstanding and 1,730,238 shares of preferred stock are outstanding and (ii) 1,852,235 shares of Common Stock are reserved for issuance upon exercise of outstanding employee, officer and director stock options and 16,990,503 shares of Common Stock are reserved for issuance upon exercise of outstanding warrants or conversion rights. All outstanding shares of capital stock of the Company have been validly issued and are fully paid and nonassessable, and no shares of capital stock of the Company are subject to, nor have any been issued in violation of, preemptive or similar rights. On the Closing Date, the rights, preferences, privileges and restrictions of the Shares will be as stated in the Certificate of Designations.

        (b)  Except as set forth above in subparagraph (a) of this Section 3.2, there are outstanding (i) no shares of capital stock or other voting securities of the Company; (ii) no securities of the Company convertible into or exchangeable for shares of capital stock or other voting securities of the Company; (iii) no options or other rights to acquire from the Company, and no obligation of the Company to issue or sell, any shares of capital stock or other voting securities of the Company or any securities of the Company convertible into or exchangeable for such capital stock or voting securities; and (iv) no equity equivalents, interests in the ownership or earnings, or other similar rights of or with respect to the Company.

        (c)  Neither the execution of this Agreement nor the performance of the Company's obligations hereunder, nor the consummation of any other transaction currently contemplated by the Company or any of its Subsidiaries, will trigger or cause any adjustment under any anti-dilution provisions or any other similar provisions contained in any agreement as currently in effect that have the effect of (i) causing a decrease in any exercise price or conversion price in any security exercisable for or convertible into shares of Common Stock (a "Common Stock Equivalent"), or (ii) causing an increase in the number of shares of Common Stock that may be acquired upon conversion or exercise of a Common Stock Equivalent.

        3.3    Authority Relative to This Agreement.    The Company has full corporate power and authority to execute, deliver, and perform this Agreement and to execute, deliver, and where applicable, perform the Ancillary Documents to which it is a party and to consummate the transactions contemplated hereby and thereby. The execution, delivery and performance by the Company of this Agreement and the execution, delivery, and where applicable, performance by it of the Ancillary Documents to which it is a party, and the consummation by it of the transactions contemplated hereby and thereby, have been (or prior to the Closing will have been) duly authorized by all necessary corporate action of the Company. This Agreement has been duly executed and delivered by the Company and constitutes, and

Exh. 1-2

each Ancillary Document executed or to be executed by the Company has been, or when executed will be, duly executed and delivered by the Company and constitutes, or when executed and delivered will constitute, a valid and legally binding obligation of the Company, enforceable against the Company in accordance with its terms, except that such enforceability may be limited by (i) applicable bankruptcy, insolvency, reorganization, moratorium, and similar laws affecting creditors' rights generally and (ii) general equitable principles (regardless of whether such enforceability is considered in a proceeding in equity or at law).

        3.4    Noncontravention.    The execution, delivery, and performance by the Company of this Agreement and the execution, delivery, and where applicable, the performance by it of Ancillary Documents to which it is a party and the consummation by it of the transactions contemplated hereby and thereby do not and will not (i) conflict with or result in a violation of any provision of the Company's Certificate of Incorporation, as amended, or the Company's Bylaws, as amended, or the charter, bylaws, partnership agreement or other governing instruments of any Subsidiary, (ii) conflict with or result in a violation of any provision of, or constitute (with or without the giving of notice or the passage of time or both) a default under, or give rise (with or without the giving of notice or the passage of time or both) to any loss of material benefit, or of any right of termination, cancellation, or acceleration under, any Material Agreement, (iii) result in the creation or imposition of any Encumbrance upon the properties of the Company or any Subsidiary or (iv) assuming compliance with the matters referred to in Section 3.5, violate any Applicable Law binding upon the Company or any Subsidiary, except, in the case of clauses (ii), (iii) and (iv) above, for any such conflicts, violations, defaults, terminations, cancellations, accelerations, or Encumbrances which would not, individually or in the aggregate, have a Material Adverse Effect on the Company.

        3.5    Consents and Approvals.    No consent, approval, order, or authorization of, or declaration, filing, or registration with, any Governmental Entity is required to be obtained or made by the Company or any Subsidiary in connection with the execution, delivery, or performance by the Company of this Agreement and the execution, delivery, and where applicable, performance of Ancillary Documents to which it is a party or the consummation of the transactions contemplated hereby and thereby, other than (i) compliance with any applicable requirements of the Securities Act; (ii) compliance with any applicable requirements of the Exchange Act; (iii) compliance with any applicable state securities laws; (iv) filing of the Certificate of Amendment of Certificate of Designations with the Delaware Secretary of State; (v) compliance with any applicable requirements of the HSR Act as a result of the exercise of any of the Warrants; and (vi) such consents, approvals, orders, or authorizations which, if not obtained, and such declarations, filings, or registrations which, if not made, would not, individually or in the aggregate, have a Material Adverse Effect on the Company. Except for such consents as are obtained before or contemporaneously with consummation of the Closing, no consent or approval of any person other than the Company, Investors or any Governmental Entity is required to be obtained or made by the Company or any Subsidiary in connection with the execution, delivery, or performance by the Company of this Agreement and execution, delivery and, where applicable, performance of the Ancillary Documents to which it is a party or the consummation of the transactions contemplated hereby and thereby, other than such consents, approvals, orders, or authorizations which, if not obtained, and such declarations, filings, or registrations which, if not made, would not, individually or in the aggregate, have a Material Adverse Effect on the Company.

        3.6    Authorization of Issuance; Reservation of Shares.    When issued and delivered pursuant to this Agreement and the Certificate of Designations against payment therefor, the Shares and the Warrants will be validly issued, fully paid and nonassessable. The Warrant Shares have been duly and validly reserved for issuance. The issuances of the Shares and the Warrants are not subject to any preemptive or similar rights.

        3.7    Financial Condition.    The audited consolidated balance sheet of the Company and its Subsidiaries as at December 31, 2001 and the related consolidated statement of income, stockholders'

Exh. 1-3

equity and cash flow of the Company and its Subsidiaries for the fiscal year ended on said date, with the opinion thereon of PricewaterhouseCoopers LLP heretofore furnished to the Investors and the unaudited consolidated balance sheet of the Company and its Subsidiaries as at September 30, 2002 and their related consolidated statements of income, stockholders' equity and cash flow of the Company and its Subsidiaries for the six-month period ended on such date heretofore furnished to the Investors, are complete and correct and fairly present the consolidated financial condition of the Company and its Subsidiaries as at said dates and the results of its operations for the fiscal year and the nine-month period on said dates, all in accordance with GAAP, as applied on a consistent basis (subject, in the case of the interim financial statements, to normal year-end adjustments). Neither the Company nor any Subsidiary has on the Closing Date any debt, trade payables, contingent liabilities, liabilities for taxes, unusual forward or long-term commitments or unrealized or anticipated losses from any unfavorable commitments, except as referred to or reflected or provided for in the Company's financial statements provided to the Investors as set forth in this Section 3.7 or in Schedule 3.7 or except to the extent that the existence of any of the foregoing would not have a Material Adverse Effect relative to the Company. Since December 31, 2001, there has been no change or event having a Material Adverse Effect relative to the Company, except as disclosed to the Investors in writing. Since December 31, 2001, neither the business nor the properties of the Company's Subsidiaries, taken as a whole, have been materially and adversely affected as a result of any fire, explosion, earthquake, flood, drought, windstorm, accident, strike or other labor disturbance, embargo, requisition or taking of property or cancellation of contracts, permits or concessions by any Governmental Entity, riot, activities of armed forces or acts of God or of any public enemy.

        3.8    Litigation.    Except as disclosed in Schedule 3.8 hereto, at the Closing Date there is no litigation, legal, administrative or arbitral proceeding, investigation or other action of any nature pending or, to the best of the Company's knowledge, threatened against or affecting the Company or any Subsidiary which both (a) involves the possibility of any judgment or liability against the Company or any Subsidiary not fully covered by insurance (except for normal deductibles), and (b) would be more likely than not to have a Material Adverse Effect relative to the Company.

        3.9    ERISA.    The Company and each ERISA Affiliate have complied in all material respects with ERISA and, where applicable, the Code regarding each Plan. Each Plan is, and has been, maintained in substantial compliance with ERISA and, where applicable, the Code.

        No act, omission or transaction has occurred which could result in imposition on the Company or any ERISA Affiliate (whether directly or indirectly) of an amount of $100,000 or more as (i) either a civil penalty assessed pursuant to section 502(c), (i) or (1) of ERISA or a tax imposed pursuant to Chapter 43 of Subtitle D of the Code or (ii) breach of fiduciary duty liability damages under section 409 of ERISA.

        No Plan (other than a defined contribution plan) or any trust created under any such Plan has been terminated since September 2, 1974. No liability to the Pension Benefit Guaranty Corporation in excess of $100,000 (other than for the payment of current premiums which are not past due) by the Company or any ERISA Affiliate has been or is expected by the Company or any ERISA Affiliate to be incurred with respect to any Plan. No ERISA Event with respect to any Plan has occurred which could reasonably be expected to result in liabilities of $100,000 or more.

        Full payment when due has been made of all amounts which the Company or any ERISA Affiliate is required under the terms of each Plan or applicable law to have paid as contributions to such Plan, and no accumulated funding deficiency in an amount of $100,000 or more (as defined in section 302 of ERISA and section 412 of the Code), whether or not waived, exists with respect to any Plan.

        The actuarial present value of the benefit liabilities under each Plan which is subject to Title IV of ERISA does not, as of the end of the Company's most recently ended fiscal year, exceed the current value of the assets (computed on a plan termination basis in accordance with Title IV of ERISA) of

Exh. 1-4

such Plan allocable to such benefit liabilities by $100,000 or more. The term "actuarial present value of the benefit liabilities" shall have the meaning specified in section 4041 of ERISA.

        None of the Company or any ERISA Affiliate sponsors, maintains, or contributes to an employee welfare benefit plan, as defined in section 3(1) of ERISA, including, without limitation, any such plan maintained to provide benefits to former employees of such entities, that may not be terminated by the Company or any ERISA Affiliate in its sole discretion at any time without any material liability.

        None of the Company or any ERISA Affiliate sponsors, maintains or contributes to, or has at any time in the preceding six calendar years, sponsored, maintained or contributed to, any Multiemployer Plan.

        None of the Company or any ERISA Affiliate is required to provide security under section 401(a)(29) of the Code due to a Plan amendment that results in an increase in current liability for the Plan.

        3.10    Taxes.    The Company has filed all United States Federal income tax returns and all other tax returns which are required to be filed by it and has paid all material taxes due pursuant to such returns or pursuant to any assessment received by the Company, except for any taxes which are being contested in good faith and by proper proceedings and against which adequate reserves are being maintained. The charges, accruals and reserves on the books of the Company in respect of taxes and other governmental charges are, in the opinion of the Company, adequate. No tax lien has been filed and, to the knowledge of the Company, no claim is being asserted with respect to any such tax, fee or other charge, except for any taxes, fees or other charges which are not material or which are being contested in good faith and by proper proceedings and against which adequate reserves are being maintained.

        3.11    Titles, etc.

        (a)  Subject to the matters set out in Schedule 3.11, each of the Company and the Subsidiaries has defensible title, in all material respects, to the material Oil and Gas Properties that are evaluated in the most recently delivered reserve report, free and clear of all Liens, other than Excepted Liens. Except for immaterial divergences, after giving full effect to the Excepted Liens, the Company owns, in all material respects, the net interests in production attributable to the Hydrocarbon Interests that are evaluated in the most recently delivered reserve report, and the ownership of such Hydrocarbon Interests shall not in any material respect obligate the Company to bear the costs and expenses relating to the maintenance, development and operations of each such Hydrocarbon Interest in an amount in excess of the working interest of such Hydrocarbon Interest (without a corresponding increase in net revenue interest). The Company does not believe, based upon information in its possession, that its most recently delivered reserve report materially overstates its oil and gas reserves, bearing in mind that reserves are evaluated based upon estimates and assumptions with respect to which reasonable minds of competent reserve engineers may differ.

        (b)  All leases and agreements necessary for the conduct of the business of the Company and the Subsidiaries are valid and subsisting, in all material respects, in full force and effect and there exists no default or event or circumstance which with the giving of notice or the passage of time or both would give rise to a default under any such lease or leases, which would have a Material Adverse Effect on the conduct of the business of the Company and the Subsidiaries.

        (c)  The Oil and Gas Properties presently owned (whether of record or beneficially owned), leased or licensed by the Company and the Subsidiaries, including, without limitation, all easements and rights of way, include all properties necessary to permit the Company and the Subsidiaries to conduct their business in all material respects in the same manner as its business has been conducted prior to the Closing Date.

Exh. 1-5

        (d)  All of the properties of the Company and the Subsidiaries which are reasonably necessary for the operation of their business are in good working condition in all material respects and are maintained in accordance with prudent business standards.

        3.12    No Material Misstatements.    Taken as a whole, the written information, statements, exhibits, certificates, documents and reports furnished to Investors by the Company or any Subsidiary in connection with the negotiation of this Agreement do not contain any material misstatement of fact or omit to state a material fact or any fact necessary to make the statements contained therein not materially misleading in the light of the circumstances in which made and with respect to the Company or any Subsidiary. As of the Closing Date, there is no fact peculiar to the Company or Subsidiary which has a Material Adverse Effect relative to the Company or in the future is reasonably likely to have (so far as the Company can now foresee) a Material Adverse Effect and which has not been set forth in this Agreement or the other documents, certificates and statements furnished to Investors by or on behalf of the Company or any Subsidiary prior to, or on, the Closing Date in connection with the transactions contemplated hereby.

        3.13    Investment Company Act.    Neither the Company nor any Subsidiary is an "investment company" or a company "controlled" by an "investment company," within the meaning of the Investment Company Act of 1940, as amended.

        3.14    Public Utility Holding Company Act.    Neither the Company nor any Subsidiary is a "holding company," or a "subsidiary company" of a "holding company," or an "affiliate" of a "holding company" or of a "subsidiary company" of a "holding company," or a "public utility" within the meaning of the Public Utility Holding Company Act of 1935, as amended.

        3.15    Subsidiaries.    Except as set forth on Schedule 3.15, the Company has no Subsidiaries. Each Subsidiary is a corporation, limited liability company or limited partnership, duly incorporated or organized, validly existing and in good standing under the laws of its jurisdiction of incorporation or organization, if applicable, and has all requisite corporate power and authority in all material respects to own, lease, and operate its properties and to carry on its business as now being conducted. Each Subsidiary is duly qualified to do business as a foreign corporation or limited partnership, if applicable, and is in good standing in each jurisdiction where such qualification is necessary, except where the failure to so qualify or to be in good standing would not reasonably be expected to have a Material Adverse Effect. There are outstanding (i) no securities of any Subsidiary of the Company convertible into or exchangeable for shares of capital stock or other voting securities of any Subsidiary of the Company and (ii) no options or other rights to acquire from any Subsidiary of the Company, and no obligation of any Subsidiary of the Company to issue or sell, any shares of capital stock or other voting securities of any Subsidiary of the Company or any securities of any Subsidiary of the Company convertible into or exchangeable for such capital stock or voting securities.

        3.16    Defaults.    Neither the Company nor any Subsidiary is in default nor has any event or circumstance occurred which, but for the expiration of any applicable grace period or the giving of notice, or both, would constitute a default under any material agreement or instrument to which the Company is a party or by which the Company is bound, which default would have a Material Adverse Effect.

        3.17    Environmental Matters.    Except for matters which are more likely than not to not have a Material Adverse Effect (or with respect to (c), (d) and (e) below, where the failure to take such actions is more likely than not to not have a Material Adverse Effect):

        (a)  To the best of the Company's knowledge, neither any Oil and Gas Property of the Company or any of its Subsidiaries nor the operations conducted thereon violate any order or requirement of any court or Governmental Entity or any Environmental Laws;

Exh. 1-6

        (b)  Without limitation of clause (a) above, no Oil and Gas Property of the Company or any of its Subsidiaries nor the operations currently conducted thereon or, to the best knowledge of the Company, by any prior owner or operator of such property or operation, are in violation of or subject to any existing, pending or threatened action, suit, investigation, inquiry or proceeding by or before any court or Governmental Entity or to any remedial obligations under Environmental Laws;

        (c)  All notices, permits, licenses or similar authorizations, if any, required to be obtained or filed by the Company or any of its Subsidiaries in connection with the operation or use of any and all Oil and Gas Property of the Company and each of its Subsidiaries, including without limitation present, or to the best of Company's knowledge, past treatment, storage, disposal or release of a hazardous substance or solid waste into the environment, have been duly obtained or filed, and the Company and each Subsidiary thereof are in compliance with the terms and conditions of all such notices, permits, licenses and similar authorizations;

        (d)  To the best of the Company's knowledge, all hazardous substances, solid waste, and oil and gas exploration and production wastes, if any, generated at any and all Oil and Gas Property of the Company and each of its Subsidiaries have in the past, during the tenure of ownership of the Company and its Subsidiaries and prior thereto, been transported, treated and disposed of in accordance with Environmental Laws and so as not to pose an imminent and substantial endangerment to public health or welfare or the environment, and, to the best knowledge of the Company, all such transport carriers and treatment and disposal facilities have been and are operating in compliance with Environmental Laws and so as not to pose an imminent and substantial endangerment to public health or welfare or the environment, and are not the subject of any existing, pending or threatened action, investigation or inquiry by any Governmental Entity in connection with any Environmental Laws;

        (e)  To the best of the Company's knowledge, no hazardous substances, solid waste, or oil and gas exploration and production wastes, have been disposed of or otherwise released and there has been no threatened release of any hazardous substances on or to any Oil and Gas Property of the Company or any of its Subsidiaries except in compliance with Environmental Laws and so as not to pose an imminent and substantial endangerment to public health or welfare or the environment; and

        (f)    To the extent applicable, all Oil and Gas Property of the Company and each of its Subsidiaries currently satisfies all design, operation, and equipment requirements imposed by the OPA or scheduled as of the Closing Date to be imposed by OPA during the term of this Agreement, and the Company does not have any reason to believe that such Oil and Gas Property, to the extent subject to OPA, will not be able to maintain compliance with the OPA requirements during the term of this Agreement; and

        (g)  Neither the Company nor any of its Subsidiaries has any known contingent liability in connection with any release or threatened release of any oil, hazardous substance or solid waste into the environment.

        3.18    Compliance with the Law.    Neither the Company nor any Subsidiary has violated any Governmental Requirement or failed to obtain any license, permit, franchise or other governmental authorization necessary for the ownership of any of its Oil and Gas Properties or the conduct of its business, which violation or failure would have (in the event such violation or failure were asserted by any Person through appropriate action) a Material Adverse Effect. Except for such acts or failures to act as would not have a Material Adverse Effect, the Oil and Gas Properties (and properties unitized therewith) have been maintained and developed, and to the best of the Company's knowledge operated, in a good and workmanlike manner and in conformity with all applicable laws and all rules, regulations and orders of all duly constituted authorities having jurisdiction and in conformity with the

Exh. 1-7

provisions of all leases, subleases or other contracts comprising a part of the Hydrocarbon Interests and other contracts and agreements forming a part of the Oil and Gas Properties; specifically in this connection, but subject to the Material Adverse Effect qualification set forth above, (i) after the Closing Date, no Oil and Gas Property is subject to having allowable production reduced below the full and regular allowable (including the maximum permissible tolerance) because of any overproduction (whether or not the same was permissible at the time) prior to the Closing Date and (ii) none of the wells comprising a part of the Oil and Gas Properties (or properties unitized therewith) are deviated from the vertical more than the maximum permitted by applicable laws, regulations, rules and orders, and such wells are, in fact, bottomed under and are producing from, and the well bores are wholly within, the Oil and Gas Properties (or in the case of wells located on properties unitized therewith, such unitized properties).

        3.19    Insurance.    Schedule 3.19 attached hereto contains an accurate and complete description of all material policies of fire, liability, workmen's compensation and other forms of insurance owned or held by the Company and each Subsidiary as of the Closing Date. All such policies are in full force and effect, all premiums with respect thereto covering all periods up to and including the Closing Date have been paid, and no notice of cancellation or termination has been received with respect to any such policy. Such policies are sufficient for compliance with all requirements of law and of all agreements to which the Company or any Subsidiary is a party; are valid, outstanding and enforceable policies; provide adequate insurance coverage in at least such amounts and against at least such risks (but including in any event public liability) as are usually insured against in the same general area by companies engaged in the same or a similar business for the assets and operations of the Company and each Subsidiary; will remain in full force and effect through the respective dates set forth in Schedule 3.19 with the payment of additional premiums; and will not in any way be affected by, or terminate or lapse by reason of, the transactions contemplated by this Agreement. Schedule 3.19 identifies all material risks, if any, which the Company, the Subsidiaries and their respective Board of Directors or officers have designated as being self insured. Neither the Company nor any Subsidiary has been refused any insurance with respect to its assets or operations, nor has its coverage been limited below usual and customary policy limits, by an insurance carrier to which it has applied for any such insurance or with which it has carried insurance during the last three years.

        3.20    Hedging Agreements.    Schedule 3.20 sets forth, as of the Closing Date, a true and complete list of all Hedging Agreements (including commodity price swap agreements, forward agreements or contracts of sale which provide for prepayment for deferred shipment or delivery of oil, gas or other commodities) of the Company and each Subsidiary.

        3.21    Material Agreements.    Set forth on Schedule 3.21 hereto is a complete and correct list of all material agreements, leases, indentures, purchase agreements, obligations in respect of letters of credit, guarantees, joint venture agreements, and other instruments in effect or to be in effect as of the Closing Date (other than Hedging Agreements) providing for, evidencing, securing or otherwise relating to any material Debt of the Company or any Subsidiary, and all obligations of the Company or any Subsidiary to issuers of surety or appeal bonds (excluding operator's bonds, plugging and abandonment bonds, and similar surety obligations obtained in the ordinary course of business) issued for account of the Company or any such Subsidiary.

        3.22    Gas Imbalances.    As of the Closing Date, except as set forth in the most recent Reserve Report furnished to Investors, on a net basis there are no gas imbalances, take or pay or other prepayments with respect to the Company's or any Subsidiary's Hydrocarbon Interests in the aggregate which would require the Company or such Subsidiary to deliver five percent (5%) or more of the monthly production from the Company's and its Subsidiaries' Hydrocarbons produced on a monthly basis from the Hydrocarbon Interests, at some future time without then or thereafter receiving full payment therefor.

Exh. 1-8

        3.23    Brokerage Fees.    The Company has not retained any financial advisor, broker, agent, or finder or paid or agreed to pay any financial advisor, broker, agent, or finder on account of the sale by the Company and the purchase by Investors of the Shares pursuant to this Agreement.

        3.24    SEC Filings.    The Company has complied in all material respects with its obligations to file with the Securities and Exchange Commission all forms, reports, schedules, statements and other documents required to be filed by it since January 1, 1999 under the Securities Act and the Exchange Act. All forms, reports, schedules, statements, and other documents (including all amendments thereto) filed by the Company with the Securities and Exchange Commission since such date are herein collectively referred to as the "SEC Filings". The SEC Filings, at the time filed, complied in all material respects with all applicable requirements of federal securities laws. None of the SEC Filings, including, without limitation, any financial statements or schedules included therein, at the time filed or as same may have been amended, contained any untrue statement of a material fact or omitted to state any material fact required to be stated therein or necessary in order to make the statements contained therein, in light of the circumstances under which they were made, not misleading.

        3.25    Stockholder Approval.    Neither the execution of this Agreement nor the consummation of the transactions contemplated hereunder require the approval of the stockholders of the Company under the applicable listing rules of the Nasdaq Stock Market, Inc.; provided, however, that certain of the anti-dilution provisions contained in the Warrants shall not be enforceable until after approval of the stockholders of the Company as set forth therein.

ARTICLE IV
REPRESENTATIONS AND WARRANTIES OF INVESTORS

        Each Investor represents and warrants to the Company that:

        4.1    Organization.    Each of DLJ Merchant Banking Partners III, LP ("MBP"); Millennium Partners II, L.P. ("MPII"); and MBP III Plan Investors, L.P. ("MPIII") is a limited partnership duly organized, validly existing and in good standing under the laws of the State of Delaware. Each of DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III, C.V.("DOP"); DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-1, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-1, C.V. ("DOP-1"); and DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-2, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-2, C.V. ("DOP-2") is a limited partnership (commanditaire vennootschap) duly organized, validly existing and in good standing under the laws of the Netherlands Antilles. DLJ MB PartnersIII GmbH & Co. KG ("MBP GmbH") is a limited partnership duly organized, validly existing and in good standing under the laws of the Republic of Germany. Each Investor has all requisite corporate power and authority in all material respects to own, lease, and operate its properties and to carry on its business as now being conducted. No actions or proceedings to dissolve either Investor are pending or, to the best knowledge of any Investor, threatened.

        4.2    Authority Relative to This Agreement.    Each Investor has full corporate or (if applicable) other power and authority to execute, deliver, and perform this Agreement and execute, deliver and, where applicable, perform the Ancillary Documents to which it is a party and to consummate the transactions contemplated hereby and thereby. The execution, delivery, and performance by each Investor of this Agreement and execution, delivery, and, where applicable, performance of the Ancillary Documents to which it is a party, and the consummation by it of the transactions contemplated hereby and thereby, have been duly authorized by all necessary corporate (if applicable) action of such Investor. This Agreement has been duly executed and delivered by each Investor and constitutes, and each Ancillary Document executed or to be executed by each Investor has been, or when executed will be, duly

Exh. 1-9

executed and delivered by such Investor and constitutes, or when executed and delivered will constitute, a valid and legally binding obligation of such Investor, enforceable against such Investor in accordance with its terms, except that such enforceability may be limited by (i) applicable bankruptcy, insolvency, reorganization, moratorium, and similar laws affecting creditors' rights generally and (ii) general equitable principles (regardless of whether such enforceability is considered in a proceeding in equity or at law).

        4.3    Noncontravention.    The execution, delivery, and performance by each Investor of this Agreement and the execution, delivery and, where applicable, performance of Ancillary Documents to which it is a party and the consummation by it of the transactions contemplated hereby and thereby do not and will not (i) conflict with or result in a violation of any provision of MBP's, MPII's or MPIII's Certificate of Limited Partnership or partnership agreement, DOP's, DOP-1's or DOP-2's Agreement of Limited Partnership, or MBP GmbH's Certificate of Kommanditgesellschaft/L.P., (ii) conflict with or result in a violation of any provision of, or constitute (with or without the giving of notice or the passage of time or both) a default under, or give rise (with or without the giving of notice or the passage of time or both) to any right of termination, cancellation, or acceleration under, any bond, debenture, note, mortgage, indenture, lease, agreement or other instrument or obligation to which any Investor is a party or by which Investor or any of its properties may be bound, (iii) result in the creation or imposition of any Encumbrance upon the properties of any Investor, or (iv) violate any Applicable Law binding upon any Investor, except, in the case of clauses (ii), (iii) and (iv) above, for any such conflicts, violations, defaults, terminations, cancellations, accelerations, or Encumbrances which would not, individually or in the aggregate, have a Material Adverse Effect on any Investor.

        4.4    Consents and Approvals.    No consent, approval, order, or authorization of, or declaration, filing, or registration with, any Governmental Entity is required to be obtained or made by Investors in connection with the execution, delivery, or performance by Investors of this Agreement and the execution, delivery and, where applicable, performance of the Ancillary Documents to which it is a party or the consummation of the transactions contemplated hereby or thereby. No consent or approval of any person other than any Governmental Entity is required to be obtained or made by any Investor in connection with the execution, delivery or performance by Investors of this Agreement and the execution, delivery and, where applicable, performance of the Ancillary Documents to which it is a party or the consummation of the transactions contemplated hereby or thereby.

        4.5    Purchase for Investment.    Each Investor understands that none of the Shares, the Warrants or the Warrant Shares have been registered under the Securities Act. Each Investor also understands that the Shares, the Warrants and the Warrant Shares are being offered and sold pursuant to an exemption from registration contained in the Securities Act based in part upon Investors' representations contained in this Agreement. Each Investor hereby represents and warrants as follows:

        (a)    Investor Bears Economic Risk.    Each Investor has substantial experience in evaluating and investing in private placement transactions of securities in companies similar to the Company so that it is capable of evaluating the merits and risks of its investment in the Company and has the capacity to protect its own interests. Without limiting the generality of the foregoing, each Investor further represents that it has such knowledge regarding the oil and gas industry and the business of the Company and the current circumstances surrounding such industry and business that it is capable of evaluating the merits and risks of the acquisition of the Shares, the Warrants and the Warrant Shares. Each Investor must bear the economic risk of this investment indefinitely unless the Shares, the Warrants or the Warrant Shares are registered pursuant to the Securities Act, or an exemption from registration is available. Each Investor understands that the Company has no present intention of registering the Shares, the Warrants or the Warrant Shares. Each Investor also understands that there is no assurance that any exemption from registration under the Securities Act will be available and that, even if available, such exemption may not allow an Investor to transfer all or any portion of the Shares, Warrants or Warrant Shares under the circumstances, in the amounts or at the times an Investor might propose.

Exh. 1-10

        (b)    Acquisition for Own Account.    Each Investor is acquiring the Shares, the Warrants and Warrant Shares for such Investor's own account for investment only, and not with a view towards their distribution.

        (c)    Investor Can Protect Its Interest.    Each Investor represents that by reason of its, or of its management's, business or financial experience, such Investor has the capacity to protect its own interests in connection with the transactions contemplated in this Agreement and the Ancillary Agreements. Further, no Investor is aware of any publication of any advertisement in connection with the transactions contemplated in the Agreement.

        (d)    Accredited Investor.    Each Investor represents that it is an accredited investor within the meaning of Regulation D under the Securities Act.

        (e)    Company Information.    Each Investor has had access to the Company's SEC Filings and has had an opportunity to discuss the Company's business, management and financial affairs with directors, officers and management of the Company and has had the opportunity to review the Company's operations and facilities. Each Investor has also had the opportunity to ask questions of, and receive answers from, the Company and its management regarding the terms and conditions of this investment. Each Investor hereby acknowledges and affirms that it has completed its own independent investigation, analysis, and evaluation of the Company and its subsidiaries, that it has made all such reviews and inspections of the business, assets, results of operations, condition (financial or otherwise), and prospects of the Company and its subsidiaries as it has deemed necessary or appropriate, and that in making its decision to enter into this Agreement and to consummate the transactions contemplated hereby it has relied solely on its own independent investigation, analysis, and evaluation of the Company and its subsidiaries, or that of its own independent advisers in evaluating its investment in the Shares, Warrants and Warrant Shares.

        (f)    Rule 144.    Each Investor acknowledges and agrees that the Shares and the Warrants, and, if issued, the Warrant Shares, must be held indefinitely unless they are subsequently registered under the Securities Act or an exemption from such registration is available. Each Investor has been advised or is aware of the provisions of Rule 144, which permits limited resale of shares purchased in a private placement subject to the satisfaction of certain conditions, including, among other things: the availability of certain current public information about the Company, the resale occurring following the required holding period under Rule 144 and the number of shares being sold during any three-month period not exceeding specified limitations.

        (g)    Transfer Restrictions.    Each Investor acknowledges and agrees that the Shares, the Warrants and the Warrant Shares are subject to restrictions on transfer as set forth in Section 5.5, below, and further understands that the Shares, the Warrants and the Warrant Shares will not have been registered pursuant to the Securities Act or any applicable state securities laws, that the Shares, the Warrants and the Warrant Shares will be characterized as "restricted securities" under federal securities laws, and that under such laws and applicable regulations the Shares, the Warrants and the Warrant Shares cannot be sold or otherwise disposed of without registration under the Securities Act or an exemption therefrom. In this connection, each Investor represents that it is familiar with Rule 144 promulgated under the Securities Act, as currently in effect, and understands the resale limitations imposed thereby and by the Securities Act. Appropriate stop transfer instructions may be issued to the transfer agent for securities of the Company (or a notation may be made in the appropriate records of the Company) in connection with the Shares, the Warrants or the Warrant Shares.

        (h)    Confirmation.    The acquisition of the Shares by an Investor at the Closing shall constitute such Investor's confirmation of the foregoing representations.

Exh. 1-11

        4.6    No Other Shares.    Except for such rights as may be conferred on an Investor under the First Purchase Agreement, the Second Purchase Agreement or by this Agreement and the Ancillary Documents, Investors do not beneficially own, directly or indirectly, any shares of capital stock or other securities of the Company or any of its Subsidiaries.

        4.7    Financial Resources.    Each Investor has the financial resources available to it as are necessary to perform its obligations to acquire the Shares pursuant to the terms of this Agreement.

        4.8    Brokerage Fees.    No Investor has retained any financial advisor, broker, agent, or finder or paid or agreed to pay any financial advisor, broker, agent, or finder on account of the sale by the Company and the purchase by Investors of the Shares pursuant to this Agreement.

ARTICLE V
ADDITIONAL AGREEMENTS

        5.1    Reasonable Best Efforts.

        (a)  Each party hereto agrees that it will use its reasonable best efforts to take, or cause to be taken, all action and to do, or cause to be done, all things reasonably necessary, proper, or advisable under Applicable Laws to consummate the transactions contemplated by this Agreement, including, without limitation, (i) cooperation in determining whether any consents, approvals, orders, authorizations, waivers, declarations, filings, or registrations of or with any Governmental Entity or third party are required in connection with the consummation of the transactions contemplated hereby; (ii) reasonable best efforts to obtain any such consents, approvals, orders, authorizations, and waivers and to effect any such declarations, filings, and registrations; (iii) reasonable best efforts to cause to be lifted or rescinded any injunction or restraining order or other order adversely affecting the ability of the parties to consummate the transactions contemplated hereby; (iv) reasonable best efforts to defend, and cooperation in defending, all lawsuits or other legal proceedings challenging this Agreement or the consummation of the transactions contemplated hereby; and (v) the execution of any additional instruments necessary to consummate the transactions contemplated hereby.

        (b)  Without limiting the generality of Section 5.1(a), to the extent required by the HSR Act, each of the parties hereto shall (i) file or cause to be filed, as promptly as practicable but in no event later than five (5) consecutive Business Days after the execution and delivery of this Agreement, with the Federal Trade Commission and the United States Department of Justice, all reports and other documents required to be filed by such party under the HSR Act concerning the transactions contemplated hereby and (ii) promptly comply with or cause to be complied with any requests by the Federal Trade Commission or the United States Department of Justice for additional information concerning such transactions, in each case so that the waiting period applicable to this Agreement and the transactions contemplated hereby under the HSR Act shall expire as soon as practicable after the execution and delivery of this Agreement. Each party hereto agrees to request, and to cooperate with the other party or parties in requesting, early termination of any applicable waiting period under the HSR Act. Notwithstanding the foregoing, if any report or other document is required to be filed by any Investor under the HSR Act solely as a result of the purchase and sale of the Shares or the Warrants (with no regard to any other securities held by such Investor or its Affiliates), the Company shall pay any and all fees and expenses, including filing fees and legal expenses, incurred by such Investor in connection with the filing of such reports or other documents and any other actions required to comply with the provisions of the HSR Act.

        5.2    Press Releases.    Except as may be required by Applicable Law or by the rules of any national securities exchange or registered securities association, prior to the Closing, neither Investors nor the Company shall issue any press release with respect to this Agreement or the transactions contemplated hereby without the prior consent of the other party (which consent shall not be unreasonably withheld under the circumstances). Any such press release required by Applicable Law or by the rules of any

Exh. 1-12

national securities exchange or registered securities association shall only be made after reasonable notice to the other party.

        5.3    Fees and Expenses.    Except as otherwise expressly provided in this Agreement, all fees and expenses, including fees and expenses of counsel, financial advisors and accountants, incurred in connection with this Agreement and the transactions contemplated hereby shall be paid by the party incurring such fee or expense.

        5.4    Survival.    The representations and warranties made herein shall survive the Closing, regardless of any investigation made by or on behalf of any party, until the second anniversary of the Closing Date; provided, however, the representations and warranties contained in Sections 3.9, 3.10 and 3.17 shall survive until the expiration of the applicable statute limitations relating to the subject matters of such representations and warranties (the "Survival Date".) All statements as to factual matters contained in any certificate or other instrument delivered by or on behalf of the Company pursuant hereto in connection with the transactions contemplated hereby shall be deemed to be representations and warranties by the Company herein for purposes of this Section 5.4. No action may be brought with respect to a breach of any representation or warranty after the Survival Date unless, prior to such time, the party seeking to bring such an action has notified the other parties of such claim, specifying in reasonable detail the nature of the loss suffered.

        5.5    Transfer Restrictions.

        (a)  Notwithstanding any provision contained in this Agreement to the contrary, each Investor agrees that it will not, directly or indirectly, sell, assign, transfer, pledge, encumber, or otherwise dispose of any of the Shares, Warrants or Warrant Shares except:

          (i)  In compliance with Rule 144; provided, however, that the Investor shall provide the Company with copies of all filings made with the Securities and Exchange Commission with respect to sales of securities under Rule 144 and with such other information and documents as the Company shall reasonably require in order to assure full compliance with Rule 144; or

        (ii)  Pursuant to a no-action letter or other interpretive statement or release of the Securities and Exchange Commission to the effect that the proposed sale or other disposition may be effected without registration under the Securities Act; or

        (iii)  Pursuant to an applicable exemption (other than Rule 144) under the Securities Act; provided, however, that the Investor shall have furnished the Company with an opinion of counsel, which opinion and counsel shall be reasonably acceptable to the Company, to the effect that such disposition does not require registration of such securities under the Securities Act; provided further, however, that no opinion of counsel shall be required in the case of a transfer to affiliates (as hereinafter defined) of Investor if such affiliates shall have furnished the Company with the representations contained in Section 4.5 of this Agreement and shall have agreed with the Company to be subject to the terms of this Agreement to the same extent as if an original holder of securities pursuant hereto. For purposes of this Section 5.5(a)(iii), "affiliates" shall mean one or more of (A) Affiliates as defined in Section 11.1, or (B) any other Investor; or

        (iv)  Pursuant to an effective registration statement filed under the Securities Act.

        (b)  It is agreed and understood by each Investor that the certificates or instruments representing the Shares, Warrants and Warrant Shares shall each 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 ANY APPLICABLE STATE SECURITIES LAWS, AND MAY NOT BE SOLD OR TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION THEREFROM. SUCH

Exh. 1-13

SECURITIES ARE SUBJECT TO THE RESTRICTIONS AND PRIVILEGES SPECIFIED IN A SECURITIES PURCHASE AGREEMENT, DATED AS OF DECEMBER 20, 2002, BETWEEN BRIGHAM EXPLORATION COMPANY AND THE INITIAL HOLDERS OF SECURITIES NAMED THEREIN, A COPY OF WHICH IS ON FILE WITH THE SECRETARY OF BRIGHAM EXPLORATION COMPANY AND WILL BE FURNISHED WITHOUT CHARGE TO THE HOLDER HEREOF UPON WRITTEN REQUEST, AND THE HOLDER OF THIS CERTIFICATE AGREES TO BE BOUND THEREBY."

        5.6    Consideration.    The sum of Five Hundred Thousand Dollars ($500,000) shall be deducted from the Purchase Price as consideration for the Investors entering into the purchase of the Units. The Company shall pay all reasonable out-of-pocket expenses ("Investor Expenses") incurred by the Investors, including attorneys' fees. At the Closing, the company shall pay $75,000 in partial payment of the Investor Expenses, with a detailed final accounting for the Investor Expenses to be submitted by the Investors within thirty (30) days after the Closing Date. The Company shall pay to the Investors such final amount of Investor Expenses (less expenses already paid at Closing) within thirty (30) days following the Company's receipt of such final accounting from the Investors.

        5.7    Action at Annual Meeting of Stockholders.

        (a)  The Company shall take all action necessary in accordance with applicable law and the Company's Certificate of Incorporation and Bylaws to have the Company's common stockholders, at the Annual Meeting to be held on or before May 31, 2003, consider and approve the matters described in the Stockholders Voting Agreement dated December 20, 2002, by and among the Company and certain of its stockholders, such approval, when so obtained, shall be referred to as the "Stockholder Approval". The Company shall not mail or otherwise distribute the proxy statement or information statement (or any related proxy materials or amendments or supplements thereto, if any) relating to the Annual Meeting to its stockholders without consultation with Investors and their counsel, and such proxy statement or information statement and such other items shall, to the extent same relate to the subject matter of the Stockholders Voting Agreement, be in such form as Investors and their counsel shall approve (such approval not to unreasonably withheld).

        (b)  The Company shall provide a certificate signed by a duly authorized officer of the Company to each holder of Warrants promptly after the Annual Meeting certifying whether the Stockholder Approval has been obtained at the Annual Meeting and whether the anti-dilution provisions contained in the Warrants are then enforceable.

        5.8    Capitalization Certificate.    The Company shall provide, immediately after the Closing, a schedule reflecting the capitalization of the Company as of immediately after the transactions contemplated by this Agreement, including at least the information provided in the representation in Section 3.2 and indicating the number of fully-diluted shares of Common Stock, and certified by the Chief Financial Officer of the Company (the "Certificate"). Until the second anniversary of the Closing Date, the Company shall amend the Certificate at any time after the Closing to reflect any changes to the Certificate (which in all cases shall reflect the capitalization of the Company as of immediately after the transactions contemplated by this Agreement) if the Company learns that the Certificate is incorrect or not complete in any respect. Notwithstanding any provision contained in this Agreement, the Amended Registration Rights Agreement and the Warrant Certificate, if the number of fully-diluted shares of common stock as reflected in the Certificate at any time is more than 33,828 shares in excess of 33,827,779 shares of Common Stock, then the number of shares purchasable upon exercise of the Warrant shall be increased to a number of shares equal to 6.796% of the fully-diluted shares of Common Stock. Upon any such adjustment to the number of shares to be acquired upon exercise of the Warrant, the holder of the Warrant shall deliver to the Company the Warrant Certificate for cancellation and immediately thereupon the Company shall issue a new Warrant Certificate reflecting the registered number of shares purchasable thereunder. For purposes of this Section 5.8, the term

Exh. 1-14

"fully-diluted shares of Common Stock" means the sum of shares of Common Stock outstanding, plus all shares of Common Stock issuable pursuant to (i) the conversion or exchange of securities that are convertible into or exchangeable for shares of Common Stock or the exercise of any option, warrant or other right to acquire shares of Common Stock from the Company, (ii) the conversion or exchange of any security that is convertible into or exchangeable for any securities referred to in Section 5.8(i) or the exercise of any security that is exercisable for any securities referenced in Section 5.8(i), and (iii) the exercise of any rights under any agreement regarding equity equivalents, interest in the ownership or earnings, or other similar rights of or with respect to the Company.

        5.9    Restrictions on Certain Actions.    Investors hereby agree (subject to the occurrence of the Closing) that for a period of one year from the Closing Date, Investors shall not, without the prior written approval of the Board of Directors of the Company, in any manner, directly or indirectly, acquire for their own accounts any Voting Securities (or beneficial ownership thereof), except by way of stock dividends or other distributions or offerings made available to holders of Voting Securities generally and except for acquisitions of Common Stock upon exercise of the Warrants (as defined herein), upon exercise of the Warrants (as defined in the First Purchase Agreement), upon exercise of the Warrants (as defined in the Second Purchase Agreement) or upon conversion of the Loans (as defined in the Assignment Agreement) in accordance with the Equity Conversion Agreement (as defined in the Assignment Agreement). The parties acknowledge that various Affiliates of the Investors are brokers or investment advisors or are otherwise engaged in transactions in securities generally as part of their ordinary course of business. The parties agree that actions taken by Affiliates of the Investors as such in the ordinary course of their business, such as acting as broker for clients acquiring shares of Voting Securities, shall not be deemed a violation of any of the provisions of this Section 5.9.

ARTICLE VI
CONDITIONS TO OBLIGATIONS OF THE COMPANY

        The obligations of the Company to consummate the transactions contemplated by this Agreement shall be subject to the fulfillment on or prior to the Closing Date of each of the following conditions:

        6.1    Representations and Warranties.    All the representations and warranties of Investors contained in this Agreement shall be true and correct in all material respects, except as affected by transactions contemplated or permitted by this Agreement.

        6.2    Covenants and Agreements.    Investors shall have performed and complied with in all material respects all covenants and agreements required by this Agreement to be performed or complied with by them on or prior to the Closing Date.

        6.3    HSR Act.    All waiting periods (and any extensions thereof) applicable to this Agreement and the transactions contemplated hereby under the HSR Act shall have expired or been terminated.

        6.4    Legal Proceedings.    No Proceeding shall, on the Closing Date, be pending or threatened seeking to restrain, prohibit or obtain damages or other relief in connection with this Agreement or the consummation of the transactions contemplated hereby.

        6.5    Consents.    All consents, approvals, orders, authorizations and waivers of, and all declarations, filings and registrations with, third parties (including Governmental Entities) required to be obtained or made by or on the part of the parties hereto, or otherwise reasonably necessary for the consummation of the transactions contemplated hereby, shall have been obtained or made, and all thereof shall be in full force and effect at the time of Closing.

Exh. 1-15

ARTICLE VII
CONDITIONS TO OBLIGATIONS OF INVESTORS

        The obligations of Investors to consummate the transactions contemplated by this Agreement shall be subject to the fulfillment on or prior to the Closing Date of each of the following conditions:

        7.1    Representations and Warranties.    All the representations and warranties of the Company contained in this Agreement shall be true and correct in all material respects, except as affected by transactions contemplated or permitted by this Agreement (or the announcement thereof).

        7.2    Covenants and Agreements.    The Company shall have performed and complied with in all material respects all covenants and agreements required by this Agreement to be performed or complied with by it on or prior to the Closing Date.

        7.3    HSR Act.    All waiting periods (and any extensions thereof) applicable to this Agreement and the transactions contemplated hereby under the HSR Act shall have expired or been terminated.

        7.4    Legal Proceedings.    No Proceeding shall, on the Closing Date, be pending or threatened seeking to restrain, prohibit or obtain damages or other relief in connection with this Agreement or the consummation of the transactions contemplated hereby.

        7.5    Consents.    All consents, approvals, orders, authorizations and waivers of, and all declarations, filings and registrations with, third parties (including Governmental Entities) required to be obtained or made by or on the part of the parties hereto, or otherwise reasonably necessary for the consummation of the transactions contemplated hereby, shall have been obtained or made, and all thereof shall be in full force and effect at the time of Closing.

        7.6    Legal Opinion.    Thompson & Knight, L.L.P., counsel to the Company, shall have delivered to the Investors a legal opinion satisfactory in form and substance to the Investors.

        7.7.    Assignment Agreement.    All conditions precedent to the effectiveness of the sale, assignment and transfer contemplated under the Assignment Agreement shall have been satisfied or waived.

        7.8    Letter Agreement.    All conditions precedent to the purchase of the Shares and Warrants contained in the Letter Agreement dated as of November 21, 2002, between the Company, BOG, and DLJ Merchant Banking III, Inc., shall have been satisfied or waived.

ARTICLE VIII
COVENANTS

        8.1    Affirmative Covenants.    The Company covenants and agrees that, so long as any of the Shares are outstanding:

        (a)    Financial Statements and Other Reports.    The Company shall deliver, or shall cause to be delivered, to the Investors:

        (i)    Annual Financial Statements.    As soon as available and in any event within 90 days after the end of each fiscal year of the Company and its consolidated Subsidiaries for such fiscal year, and the related consolidated and unaudited consolidating balance sheets of the Company and its consolidated Subsidiaries as at the end of such fiscal year, and setting forth in each case in comparative form the corresponding figures for the preceding fiscal year, and accompanied by the related opinion of independent public accountants which opinion shall state that said financial statements fairly present the consolidated financial condition and results of operations of the Company and its consolidated Subsidiaries as at the end of, and for, such fiscal year and that such financial statements have been prepared in accordance with GAAP except for such changes in such principles with which the independent public accountants shall have concurred.

Exh. 1-16

        (ii)    Quarterly Financial Statements.    As soon as available and in any event within 60 days after the end of each of the first three fiscal quarterly periods of each fiscal year of the Company, consolidated statements of income, stockholders' equity, changes in financial position and cash flow of the Company and its consolidated Subsidiaries for such period and for the period from the beginning of the respective fiscal year to the end of such period, and the related consolidated and consolidating balance sheets as at the end of such period.

        (iii)    Monthly Financial Statements.    As soon as available and in any event within forty-five (45) days after the end of each calendar month that is not also the end of one of the Company's first three fiscal quarterly periods or of the Company's fiscal year, consolidated statements of income and changes in financial position of the Company and its consolidated Subsidiaries for such period and for the period from the beginning of the respective fiscal year to the end of such period, and the related consolidated balance sheets as at the end of such period and beginning statements setting forth in each case in comparative form the corresponding figures for the corresponding period in the preceding fiscal year.]

        (b)    SEC Filings, Etc.    Promptly, upon its becoming available, each financial statement, report, notice or proxy statement sent by the Company to stockholders generally.

        (c)    Engineering Reports.    Not later than April 30 and October 30 of each year, the Company shall furnish to the Investors a Reserve Report as of the preceding December 31 and June 30, respectively. The Reserve Report to be furnished in April of each year shall be prepared by certified independent petroleum engineers or other independent petroleum consultant(s) and the Reserve Report to be furnished in October of each year shall be prepared by or under the supervision of the chief engineer or Vice President of Operations of the Company who shall certify such Reserve Report to have been prepared in accordance with the procedures used in the immediately preceding April Reserve Report. At Company's option, the Reserve Report to be furnished in October of each year may instead consist of a report from the independent petroleum engineers referred to above on any new wells and a roll-forward by Company on any wells previously reported in the Reserve Report described in the immediately preceding April.

        (d)    Exchange Act Reports.    At all times (i) timely file all reports required to be filed by the Company under Section 13(d) or Section 15 of the Exchange Act and the rules and regulations thereunder, and (ii) if the Company is no longer subject to the requirements of the Exchange Act, provide holders of the Shares reports in substantially the same form and at the same times as would be required if the Company were subject to the Exchange Act.

        (e)    Nasdaq Listing.    Maintain at all times a valid listing for the Common Stock on a national securities exchange or the National Market System or SmallCap Market of the NASDAQ Stock Market, Inc.

        (f)    Further Assurances.    The Company at its expense will promptly execute and deliver to the Investors upon request all such other documents, agreements and instruments to comply with or accomplish the covenants and agreements of the Company in this Agreement or any other agreements and documents executed by and between the Company and the Investors.

        8.2    Negative Covenants.    The Company covenants and agrees that, so long as at least 10% of the Shares are outstanding, without the prior written consent of the persons holding 75% of the then outstanding Shares:

        (a)    Dividends, Distributions and Redemptions.    The Company will not declare or pay any dividend, purchase, redeem, or otherwise acquire for value any, other than those issued under the First Purchase Agreement or the Second Purchase Agreement, Parity Security or Junior Security now or hereafter outstanding, return any capital or make a distribution of its assets to its stockholders.

        (b)    Nature of Business.    Neither the Company nor Brigham Oil & Gas, L.P. will allow any material change to be made in the character of its business as an independent oil and gas exploration and production company.

Exh. 1-17

        (c)    Environmental Matters.    Neither the Company nor any Subsidiary will knowingly cause or permit any of its Property to be in violation of, or knowingly do anything or permit anything to be done which will subject any such Property to any remedial obligations under any Environmental Laws, assuming disclosure to the applicable Governmental Authority of all relevant facts, conditions and circumstances, if any, pertaining to such Property where such violations or remedial obligations would have a Material Adverse Effect.

        (d)    Transactions with Affiliates.    Neither the Company nor any Subsidiary will enter into any transaction, including, without limitation, any purchase, sale, lease or exchange of Property or the rendering of any service, with any Affiliate unless such transactions are otherwise not in violation of this Agreement, and are upon fair and reasonable terms no less favorable to it than it would obtain in a comparable arm's length transaction with a Person not an Affiliate.

        8.3    Venture Capital Investment.    The rights contained in this Section 8 are intended to satisfy the requirement of management rights for purposes of qualifying the ownership of Common Stock, Preferred Stock and Warrants by one or more of the Investors as a venture capital investment for purposes of the Department of Labor "plan asset" regulation, 29 C.F.R. § 2510.3-101. In the event such rights are not satisfactory for such purpose, the Company and such Investors shall reasonably cooperate in good faith to agree upon mutually satisfactory management rights that satisfy such regulation.

        8.4    Amended Registration Rights Agreement.    Within two business days after the Closing, the Company shall execute and deliver to the Investors the Second Amendment to Registration Rights Agreement by and among the Company, the Investors, MB and ESC.

ARTICLE IX
AMENDMENT AND WAIVER

        9.1    Amendment.    This Agreement may not be amended except by an instrument in writing signed by or on behalf of all the parties hereto.

        9.2    Waiver.    No failure or delay by a party hereto in exercising any right, power, or privilege hereunder shall operate as a waiver thereof nor shall any single or partial exercise thereof preclude any other or further exercise thereof or the exercise of any other right, power, or privilege. The provisions of this Agreement may not be waived except by an instrument in writing signed by or on behalf of the party against whom such waiver is sought to be enforced.

ARTICLE X
MISCELLANEOUS

        10.1    Notices.    All notices, requests, demands, and other communications required or permitted to be given or made hereunder by any party hereto shall be in writing and shall be deemed to have been duly given or made if (i) delivered personally, (ii) sent by prepaid overnight courier service, or (iii) sent by telecopy or facsimile transmission, answer back requested, to the parties at the following addresses (or at such other addresses as shall be specified by the parties by like notice):

(a)

If to the Company:

Brigham Exploration Company
6300 Bridge Point Parkway
Building 2, Suite 500
Austin, TX 78730
Attention: Chief Financial Officer
Telefax: 512-427-3400

Exh. 1-18

with a copy to:

Thompson & Knight L.L.P.
1700 Pacific Avenue, Suite 3300
Dallas, Texas 75201
Attention: Joe Dannenmaier
Telefax: 214-969-1751

(b)

If to the Investors at:

Global Energy Partners
1100 Louisiana Street
Houston, Texas 77002
Fax: 713-890-1429
Attn: Steven A. Webster

and

CSFB Private Equity
11 Madison Avenue
New York, New York 10010
Fax: 917-326-8076
Attn: Ivy Dodes

with a copy to:

Gardere Wynne Sewell, LLP
1000 Louisiana, Suite 3400
Houston, Texas 77002
Attention: N.L. Stevens III
Telefax: 713-276-5807

Such notices, requests, demands, and other communications shall be effective (i) if delivered personally or sent by courier service, upon actual receipt by the intended recipient, or (ii) if sent by telecopy or facsimile transmission, when the answer back is received.

        10.2    Entire Agreement.    This Agreement, together with the Schedules, Exhibits, Annexes, and other writings referred to herein or delivered pursuant hereto, constitutes the entire agreement between the parties hereto with respect to the subject matter hereof and supersedes all prior agreements and understandings, both written and oral, between the parties and their Affiliates with respect to the subject matter hereof.

        10.3    Binding Effect; Assignment; No Third Party Benefit.    This Agreement shall be binding upon and inure to the benefit of the parties hereto and their respective successors and permitted assigns. Except as otherwise expressly provided in this Agreement, neither this Agreement nor any of the rights, interests or obligations hereunder shall be assigned by any of the parties hereto without the prior written consent of the other party. Nothing in this Agreement, express or implied, is intended to or shall confer upon any person other than the parties hereto, and their respective heirs, legal representatives, successors, and permitted assigns, any rights, benefits or remedies of any nature whatsoever under or by reason of this Agreement.

        10.4    Severability.    If any provision of this Agreement is held to be unenforceable, then this Agreement shall be considered divisible and such provision shall be deemed inoperative to the extent it is deemed unenforceable, and in all other respects this Agreement shall remain in full force and effect to the maximum extent permitted by Applicable Law.

Exh. 1-19

        10.5    Injunctive Relief.    The parties hereto acknowledge and agree that irreparable damage would occur in the event any of the provisions of this Agreement were not performed in accordance with their specific terms or were otherwise breached. It is accordingly agreed that the parties shall be entitled to an injunction or injunctions to prevent breaches of the provisions of this Agreement, and shall be entitled to enforce specifically the provisions of this Agreement, in any court of the United States or any state thereof having jurisdiction, in addition to any other remedy to which the parties may be entitled under this Agreement or at law or in equity.

        10.6    Governing Law.THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED AND ENFORCED IN ACCORDANCE WITH THE LAWS OF THE STATEOF NEW YORK, WITHOUT REGARD TO THE PRINCIPLES OF CONFLICTS OF LAWS THEREOF.

        10.7    Jurisdiction.    Except as otherwise expressly provided in this Agreement, any suit, action or proceeding seeking to enforce any provision of, or based on any matter arising out of or in connection with, this Agreement or the transactions contemplated hereby may be brought in the United States District Court for the Southern District of New York or any other New York State court sitting in New York City, and each of the parties hereby consents to the jurisdiction of such courts (and of the appropriate appellate courts therefrom) in any such suit, action or proceeding and irrevocably waives, to the fullest extent permitted by law, any objection which it may now or hereafter have to the laying of the venue of any such suit, action or proceeding in any such court or that any such suit, action or proceeding which is brought in any such court has been brought in an inconvenient forum. Process in any such suit, action or proceeding may be served on any party anywhere in the world, whether within or without the jurisdiction of any such court. Without limiting the foregoing, each party agrees that service of process on such party as provided in Section 10.01 shall be deemed effective service of process on such party.

        10.8    Counterparts.    This Agreement may be executed by the parties hereto in any number of counterparts, each of which shall be deemed an original, but all of which shall constitute one and the same agreement. Each counterpart may consist of a number of copies hereof each signed by less than all, but together signed by all, the parties hereto.

ARTICLE XI
DEFINITIONS

        11.1    Certain Defined Terms.    As used in this Agreement, each of the following terms has the meaning given it in this Article:

        "Affiliate" of any Person shall mean (i) any Person directly or indirectly controlled by, controlling or under common control with such first Person, (ii) any director or officer of such first Person or of any Person referred to in clause (i) above and (iii) if any Person in clause (i) above is an individual, any member of the immediate family (including parents, spouse and children) of such individual and any trust whose principal beneficiary is such individual or one or more members of such immediate family and any Person who is controlled by any such member or trust. For purposes of this definition, any Person which owns directly or indirectly 50% or more of the securities having ordinary voting power for the election of directors or other governing body of a corporation or 50% or more of the partnership or other ownership interests of any other Person (other than as a limited partner of such other Person) will be deemed to "control" (including, with its correlative meanings, "controlled by" and "under common control with") such corporation or other Person.

        "Ancillary Documents" means each agreement, instrument, and document (other than this Agreement) executed or to be executed by the Company or any Investor in connection with the sale and purchase of the Shares and Warrants and the other transactions contemplated by this Agreement.

Exh. 1-20

        "Applicable Law" means any statute, law, rule, or regulation or any judgment, order, writ, injunction, or decree of any Governmental Entity to which a specified person or property is subject.

        "Assignment Agreement" means the Assignment Agreement dated as of November 21, 2002, by and between Shell Capital Inc. as Assignor and the Investors as Assignees.

        "BOG" means Brigham Oil & Gas, L.P.

        "Business Day" shall mean any day other than a Saturday, a Sunday, or a day on which banking institutions in Austin, Texas are authorized or obligated by law or executive order to close.

        "Code" shall mean the Internal Revenue Code of 1986, as amended from time to time and any successor statute.

        "Common Stock" means the common stock, par value of $.01 per share, of the Company, and such other class of securities as shall represent the common equity of the Company.

        "Debt" shall mean, for any Person the sum of the following (without duplication): (i) all obligations of such Person for borrowed money or evidenced by bonds, debentures, notes or other similar instruments (including principal, interest, fees and charges); (ii) all obligations of such Person (whether contingent or otherwise) in respect of bankers acceptances, letters of credit, surety or other bonds and similar instruments; (iii) all obligations of such Person to pay the deferred purchase price of Property or services (other than for borrowed money) excluding Trade Payables; (iv) all obligations under leases which shall have been, or should have been, in accordance with GAAP, recorded as capital leases in respect of which such Person is liable (whether contingent or otherwise); (v) all obligations under leases (other than capital leases and oil and gas leases) which require such Person or its Affiliate to make payments exceeding $100,000 over the term of such lease, including payments at termination, which are substantially equal to at least eighty percent (80%) of the purchase price of the Property subject to such lease plus interest at an imputed market rate of interest; (vi) all Debt (as described in the other clauses of this definition) of others secured by a Lien on any asset of such Person, whether or not such Debt is assumed by such Person; (vii) all Debt (as described in the other clauses of this definition) of others guaranteed by such Person or in which such Person otherwise assures a creditor against loss of the Debt of others; (viii) all obligations or undertakings of such Person to maintain or cause to be maintained the financial position or covenants of others including without limitation agreements expressed as an agreement to purchase the Debt or Property of others or otherwise; (x) obligations to pay for goods or services whether or not such goods or services are actually received or utilized by such Person; (xi) any capital stock of such Person in which such Person has a mandatory obligation to redeem such stock; (xii) the undischarged balance of any production payment created by such Person or for the creation of which such Person directly or indirectly received payment; and (xiii) all obligations of such Person under Hedging Agreements.

        "Encumbrances" means liens, charges, pledges, options, mortgages, deeds of trust, security interests, claims, restrictions (whether on voting, sale, transfer, disposition, or otherwise), easements, and other encumbrances of every type and description, whether imposed by law, agreement, understanding, or otherwise.

        "Environmental Laws" shall mean any and all Governmental Requirements pertaining to the environment in effect in any and all jurisdictions in which the Company or any Subsidiary is conducting or at any time has conducted business, or where any Oil and Gas Property of the Company or any Subsidiary is located, including without limitation, the Oil Pollution Act of 1990 ("OPA"), the Clean Air Act, as amended, the Comprehensive Environmental, Response, Compensation, and Liability Act of 1980 ("CERCLA"), as amended, the Federal Water Pollution Control Act, as amended, the Occupational Safety and Health Act of 1970, as amended, the

Exh. 1-21

Resource Conservation and Recovery Act of 1976 ("RCRA"), as amended, the Safe Drinking Water ACT, as amended, the Toxic Substances Control Act, as amended, the Superfund Amendments and Reauthorization Act of 1986, as amended, the Hazardous Materials Transportation Act, as amended, and other environmental conservation or protection laws. As used in the provisions hereof relating to Environmental Laws, the term "oil" shall have the meaning specified in OPA, the terms "hazardous substance" and "release" (or "threatened release") have the meanings specified in CERCLA, and the terms "solid waste" and "disposal" (or "disposal") have the meanings specified in RCRA; provided that to the extent the laws of the state in which any Oil and Gas Property of the Company or any Subsidiary is located establish a meaning for "oil", "hazardous substance," "release," "solid waste" or "disposal" which is broader than that specified in either OPA, CERCLA or RCRA, such broader meaning shall apply.

        "ERISA" shall mean the Employee Retirement Income Security Act of 1974, as amended from time to time and any successor statute.

        "ERISA Affiliate" shall mean each trade or business (whether or not incorporated) which together with the Company or any Subsidiary of the Company would be deemed to be a "single employer" within the meaning of section 4001(b)(1) of ERISA or subsections (b), (c), (m) or (o) of section 414 of the Code.

        "ESC" means DLJ ESC II, LP, a Delaware limited partnership.

        "Excepted Liens" shall mean: (i) Liens for taxes, assessments or other governmental charges or levies not yet due or which are being contested in good faith by appropriate action and for which adequate reserves have been maintained in accordance with GAAP; (ii) Liens in connection with workmen's compensation, unemployment insurance or other social security, old age pension or public liability obligations not yet due or which are being contested in good faith by appropriate action and for which adequate reserves have been maintained in accordance with GAAP; (iii) operators', vendors', carriers', warehousemen's, repairmen's, mechanics', workmen's, materialmen's, construction or other like Liens arising by operation of law in the ordinary course of business or incident to the exploration, development, operation and maintenance of Oil and Gas Properties or customary landlord's liens, each of which is in respect of obligations that have not been outstanding more than 90 days or which are being contested in good faith by appropriate proceedings and for which adequate reserves have been maintained in accordance with GAAP; (iv) any Liens reserved in leases or farmout agreements for rent or royalties and for compliance with the terms of the farmout agreements or leases in the case of leasehold estates, to the extent that any such Lien referred to in this clause does not materially impair the use of the property covered by such Lien for the purposes for which such property is held or materially impair the value of such property subject thereto; (v) encumbrances (other than to secure the payment of borrowed money or the deferred purchase price of property or services), easements, restrictions, servitudes, permits, conditions, covenants, exceptions or reservations in any rights of way or other property for the purpose of roads, pipelines, transmission lines, transportation lines, distribution lines for the removal of gas, oil, coal or other minerals or timber, and other like purposes, or for the joint or common use of real estate, rights of way, facilities and equipment, and defects, irregularities, zoning restrictions and deficiencies in title of any rights of way or other property which in the aggregate do not materially impair the use of such rights of way or other property for the purposes of which such rights of way and other property are held or materially impair the value of such property subject thereto; (vi) deposits of cash or securities to secure the performance of bids, trade contracts, leases, statutory obligations and other obligations of a like nature incurred in the ordinary course of business; and (vii) Liens (including "Excepted Liens") permitted by or created pursuant to the Senior Credit Agreement and Liens permitted by or created pursuant to the Subordinated Credit Agreement.

Exh. 1-22

        "Exchange Act" means the Securities Exchange Act of 1934, as amended.

        "First Purchase Agreement" means that certain Securities Purchase Agreement dated as of November 1, 2000, between the Company, MB and ESC.

        "Governmental Entity" means any court or tribunal in any jurisdiction (domestic or foreign) or any public, governmental, or regulatory body, agency, department, commission, board, bureau, or other authority or instrumentality (domestic or foreign).

        "Governmental Requirement" shall mean any law, statute, code, ordinance, order, determination, rule, regulation, judgment, decree, injunction, franchise, permit, certificate, license, authorization or other directive or requirement (in the case of banking regulatory authorities whether or not having the force of law), including, without limitation, Environmental Laws, energy regulations and occupational, safety and health standards or controls, of any Governmental Entity.

        "Hedging Agreements" shall mean any commodity, interest rate or currency swap, cap, floor, collar, forward agreement or other exchange or protection agreements or any option with respect to any such transaction.

        "HSR Act" means the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended.

        "Hydrocarbon Interests" shall mean all rights, titles, interests and estates now or hereafter acquired in and to oil and gas leases, oil, gas and mineral leases, or other liquid or gaseous hydrocarbon leases, mineral fee interests, overriding royalty and royalty interests, net profit interests and production payment interests, including any reserved or residual interests of whatever nature.

        "Hydrocarbons" shall mean oil, gas, casinghead gas, drip gasoline, natural gasoline, condensate, distillate, liquid hydrocarbons, gaseous hydrocarbons and all products refined or separated therefrom.

        "Lien" shall mean any interest in property securing an obligation owed to, or a claim by, a person other than the owner of the property, whether such interest is based on the common law, statute or contract, and whether such obligation or claim is fixed or contingent, and including but not limited to (i) the lien or security interest arising from a mortgage, encumbrance, pledge, security agreement, conditional sale or trust receipt or a lease, consignment or bailment for security purposes or (ii) production payments and the like payable out of Oil and Gas Properties. The term "Lien" shall include reservations, exceptions, encroachments, easements, rights of way, covenants, conditions, restrictions, leases and other title exceptions and encumbrances affecting property. For the purposes of this Agreement, a Person shall be deemed to be the owner of any property which it has acquired or holds subject to a conditional sale agreement, or leases under a financing lease or other arrangement pursuant to which title to the Property has been retained by or vested in some other Person in a transaction intended to create a financing.

        "Material Adverse Effect" means, relative to the Company or the Investors, as the case may be, any change, development, or effect (individually or in the aggregate) which is, or is reasonably likely to be, materially adverse (i) to the business, assets, results of operations, condition (financial or otherwise), or prospects of the Company and the Subsidiaries considered as a whole, or the Investors, as the case may be, or (ii) to the ability of the Company or the Investors, as the case may be, to perform on a timely basis any material obligation of the Company or the Investors, as the case may be, under this Agreement or any agreement, instrument, or document entered into or delivered in connection herewith.

        "Material Agreement" means (a) any written agreement, contract, lease, commitment, understanding, instrument or obligation to which the Company or any Subsidiary is a party or by which the Company or any Subsidiary or any of their respective properties may be bound involving

Exh. 1-23

total value or consideration or liability in excess of $500,000, (b) any loan or credit agreement, bond, debenture, note, mortgage or indenture by which the Company or any Subsidiary or any of their respective properties may be bound, or (c) any agreement set forth as an exhibit to the Company's Form 10-K for the fiscal year ended December 31, 2001.

        "MB" means DLJMB Funding III, Inc., a Delaware corporation.

        "Oil and Gas Properties" shall mean Hydrocarbon Interests; the Properties now or hereafter pooled or unitized with Hydrocarbon Interests; all presently existing or future unitization, pooling agreements and declarations of pooled units and the units created thereby (including without limitation all units created under orders, regulations and rules of any Governmental Authority) which may affect all or any portion of the Hydrocarbon Interests; all operating agreements, contracts and other agreements which relate to any of the Hydrocarbon Interests or the production, sale, purchase, exchange or processing of Hydrocarbons from or attributable to such Hydrocarbon Interests; all Hydrocarbons in and under and which may be produced and saved or attributable to the Hydrocarbon Interests, including all oil in tanks, the lands covered thereby and all rents, issues, profits, proceeds, products, revenues and other incomes from or attributable to the Hydrocarbon Interests; all tenements, hereditaments, appurtenances and Properties in any manner appertaining, belonging, affixed or incidental to the Hydrocarbon Interests; and all Properties, rights, titles, interests and estates described or referred to above, including any and all Property, real or personal, now owned or hereinafter acquired and situated upon, used, held for use or useful in connection with the operating, working or development of any of such Hydrocarbon Interests or Property (excluding drilling rigs, automotive equipment or other personal property which may be on such premises for the purpose of drilling a well or for other similar temporary uses) and including any and all oil wells, gas wells, injection wells or other wells, buildings, structures, fuel separators, liquid extraction plants, plant compressors, pumps, pumping units, field gathering systems, tanks and tank batteries, fixtures, valves, fittings, machinery and parts, engines, boilers, meters, apparatus, appliances, tools, implements, cables, wires, towers, casing, tubing and rods, similar equipment, surface leases, rights-of-way, easements and servitudes together with all additions, substitutions, replacements, accessions and attachments to any and all of the foregoing.

        "Person" or "person" means any individual, corporation, partnership, joint venture, association, joint-stock company, trust, enterprise, unincorporated organization, or Governmental Entity.

        "Plan" shall mean any employee pension benefit plan, as defined in Section 3(2) of ERISA, which (i) is currently or hereafter sponsored, maintained or contributed to by the Company, any Subsidiary or an ERISA Affiliate or (ii) was at any time during the preceding six calendar years sponsored, maintained or contributed to, by the Company, any Subsidiary or an ERISA Affiliate.

        "Proceeding" means any action, suit or proceeding, whether civil, criminal, administrative, arbitrative or investigative, any appeal in such an action, suit or proceeding, and any inquiry or investigation that could lead to such an action, suit or proceeding.

        "Reasonable best efforts" means a party's best efforts in accordance with reasonable commercial practice and without the incurrence of unreasonable expense.

        "Rule 144" means Rule 144 promulgated under the Securities Act.

        "Second Purchase Agreement" means that certain Securities Purchase Agreement dated as of March 5, 2001, between the Company, MB, MBP, DOP and ESC.

        "Securities Act" means the Securities Act of 1933, as amended.

        "Senior Credit Agreement" means that certain Amended and Restated Credit Agreement dated as of February 17, 2000, by and between BOG, Bank of Montreal, as Agent, and the

Exh. 1-24

Lenders signatory thereto, as amended on October 31, 2000, together with the "Loan Documents" described therein.

        "Subordinated Credit Agreement" means the Subordinated Credit Agreement dated as of October 31, 2000 by and between BOG, Shell Capital, Inc., as Agent, and the Lenders signatory thereto, together with the "Loan Documents" described therein.

        "Subsidiaries" means Brigham Oil & Gas, L.P.; Brigham, Inc.; Brigham Holdings I, LLC and Brigham Holdings II, LLC.

        "to the best of the Company's knowledge" and similar references to the knowledge of the Company mean the actual knowledge of the executive officers and senior management personnel of the Company after making a reasonable inquiry of individuals responsible for the particular matter.

        "Voting Securities" means shares of Common Stock and any other securities of the Company entitled to vote generally for the election of directors or any other securities (including, without limitation, rights, warrants, and options) convertible into or exchangeable or exercisable for any of the foregoing (whether or not presently convertible, exchangeable, or exercisable).

Exh. 1-25

        IN WITNESS WHEREOF, the parties have executed this Agreement, or caused this Agreement to be executed by their duly authorized representatives, all as of the day and year first above written.

THE COMPANY:
BRIGHAM EXPLORATION COMPANY
By:	/s/  DAVID T. BRIGHAM
	Name:	David T. Brigham
	Title:	Executive Vice President Land and Administration

INVESTORS:
DLJ MERCHANT BANKING PARTNERS III, L.P.
By:	DLJ MERCHANT BANKING III, INC., its Managing General Partner
By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact
DLJ MERCHANT BANKING III, INC., AS ADVISORY GENERAL PARTNER ON BEHALF OF DLJ OFFSHORE PARTNERS III, C.V.
By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact
DLJ MERCHANT BANKING III, INC., AS ADVISORY GENERAL PARTNER ON BEHALF OF DLJ OFFSHORE PARTNERS III-1, C.V. AND AS ATTORNEY-IN-FACT FOR DLJ MERCHANT BANKING III, L.P., AS ASSOCIATE GENERAL PARTNER OF DLJ OFFSHORE PARTNERS III-1, C.V.
By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact

Exh. 1-26

DLJ MERCHANT BANKING III, INC., AS ADVISORY GENERAL PARTNER ON BEHALF OF DLJ OFFSHORE PARTNERS III-2, C.V. AND AS ATTORNEY-IN-FACT FOR DLJ MERCHANT BANKING III, L.P., AS ASSOCIATE GENERAL PARTNER OF DLJ OFFSHORE PARTNERS III-2, C.V.
By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact

DLJ MB PARTNERSIII GmbH & CO. KG
By:	DLJ MERCHANT BANKING III, L.P., its Managing Limited Partner
	By:	DLJ MERCHANT BANKING III, INC., its General Partner
		By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact
MILLENNIUM PARTNERS II, L.P.
By:	DLJ MERCHANT BANKING III, INC., its Managing General Partner
	By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact
MBP III PLAN INVESTORS, L.P.
By:	DLJ LBO PLANS MANAGEMENT CORPORATION, its Managing General Partner
	By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact

Exh. 1-27

SCHEDULE A

Name	No. of Shares	No. of Warrants
DLJ Merchant Banking Partners III, L.P.	360,450	1,657,241
DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III, C.V.	19,632	90,262
DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-1, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-1, C.V.	6,571	30,211
DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-2, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-2, C.V.	4,681	21,522
DLJ MB PartnersIII GmbH & Co. KG	3,106	14,280
Millennium Partners II, L.P.	626	2,878
MBP III Plan Investors, L.P.	104,934	482,456

Exh. 1-28

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EXHIBIT 1

SECURITIES PURCHASE AGREEMENT
SCHEDULE A

EX-2

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EXHIBIT 2

THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY APPLICABLE STATE SECURITIES LAWS, AND MAY NOT BE SOLD OR TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION THEREFROM. SUCH SECURITIES ARE SUBJECT TO THE RESTRICTIONS AND PRIVILEGES SPECIFIED IN THIS WARRANT CERTIFICATE AND IN A SECURITIES PURCHASE AGREEMENT, DATED AS OF DECEMBER 20, 2002, BETWEEN BRIGHAM EXPLORATION COMPANY AND THE INITIAL HOLDER OF SECURITIES NAMED THEREIN, A COPY OF WHICH IS ON FILE WITH THE SECRETARY OF BRIGHAM EXPLORATION COMPANY AND WILL BE FURNISHED WITHOUT CHARGE TO THE HOLDER HEREOF UPON WRITTEN REQUEST, AND THE HOLDER OF THIS CERTIFICATE AGREES TO BE BOUND THEREBY.

WARRANT CERTIFICATE

Number of Warrants: 1,657,241 Warrant No. W-001

        This Warrant certificate ("Warrant Certificate") certifies that, for value received, DLJ Merchant Banking Partners III, L.P. is the registered holder of the number of warrants (the "Warrants") set forth above. Each Warrant entitles the holder thereof, at any time or from time to time during the Exercise Period, to purchase from the Company one fully paid and nonassessable share of Common Stock at the Exercise Price, subject to adjustment as provided herein. Initially capitalized terms used but not defined herein shall have the meanings ascribed to them in the Securities Purchase Agreement.

        "Common Stock" means the common stock, $.01 par value per share, of the Company and such other class of securities as shall then represent the common equity of the Company.

        "Company" means Brigham Exploration Company, a Delaware corporation.

        "Exercise Deferral Period" means the period of time beginning on the Issuance Date and ending six months after the Issuance Date.

        "Exercise Period" means the period of time beginning six months after the Issuance Date and ending at 5:00 p.m. (New York City time) on the Expiration Date.

        "Exercise Price," subject in all circumstances to adjustment in accordance with Section 2, means $4.35 per share.

        "Expiration Date" means the tenth anniversary of the Issuance Date.

        "Issuance Date" means December 20, 2002.

        "Person" means any individual, corporation, company, partnership, joint venture, trust, limited liability company, unincorporated organization or government or any agency, instrumentality or political subdivision thereof, or any other form of entity.

        "Preferred Stock" means shares of the Series B Preferred Stock, par value $0.01 per share, of the Company.

        "Preferred Value" per share of Preferred Stock means the Stated Value of such Share, plus, without duplication, all accrued and unpaid dividends on such share to and including the applicable date of Warrant exercise.

        "Price" means the average of the "high" and "low" prices as reported in The Wall Street Journal's listing for such day (corrected for obvious typographical errors) or if such shares are not

Exh. 2-1

reported in such listing, the average of the reported high and low sales prices on the largest national securities exchange (based on the aggregate dollar value of securities listed) on which such shares are listed or traded, or if such shares are not listed or traded on any national securities exchange, then the average of the reported high and low sales prices for such shares in the over-the-counter market, as reported on the National Association of Securities Dealers Automated Quotations System, or, if such prices shall not be reported thereon, the average of the closing bid and asked prices so reported, or, if such prices shall not be reported, then the average of the closing bid and asked prices reported by the National Quotations Bureau Incorporated. The "Average" Price per share for any period shall be determined by dividing the sum of the Prices determined for the individual trading days in such period by the number of trading days in such period.

        "Securities Purchase Agreement" means the Securities Purchase Agreement, dated as of December 20, 2002, between the Company and the Credit Suisse First Boston entities listed in Schedule A thereto.

        "Stated Value" means the stated value per share of Preferred Stock, which is $20.00 per share.

        Section 1.    Exercise of Warrants.    (a) The Warrants may be exercised in whole or in part, at any time or from time to time, during the Exercise Period, by (i) presentation and surrender to the Company at its address set forth in Section 10 of this Warrant Certificate with the Election To Exercise, attached hereto as Exhibit A, duly completed and executed, and (ii) payment of the Exercise Price, for the number of Warrants being exercised by either: (1) bank draft or cashiers check, or (2) provided that the Company receives at least 5 days prior notice and subject to Section 1(d), delivery to the Company of certificate(s) representing a number of shares of Preferred Stock having an aggregate Preferred Value equal to the aggregate Exercise Price for the number of Warrants being exercised. If the aggregate Preferred Value of the Preferred Stock delivered in payment of the aggregate Exercise Price exceeds (because of fractional shares) the aggregate Exercise Price for the number of Warrants being exercised; then (subject to Section 1(d)) the Company will promptly pay to the holder of the Warrants in cash such excess amount; provided that such excess amount shall in no event be more than the Preferred Value of one share of Preferred Stock. If the holder of this Warrant Certificate at any time exercises less than all the Warrants, the Company shall issue to such a holder a warrant certificate identical in form to this Warrant Certificate, but evidencing a number of Warrants equal to the number of Warrants originally represented by this Warrant Certificate less the number of Warrants previously exercised. Likewise, upon the presentation and surrender of this Warrant Certificate to the Company at its address set forth in Section 10 and at the request of the holder, the Company will, without expense, at the option of the holder, issue to the holder in substitution for this Warrant Certificate one or more warrant certificates in identical form and for an aggregate number of Warrants equal to the number of Warrants evidenced by this Warrant Certificate.

        (b)  To the extent that the Warrants have not been exercised at or prior to the Expiration Date, such Warrants shall expire and the rights of the holder shall become void and of no effect.

        (c)  Upon surrender of this Warrant Certificate in conformity with the foregoing provisions, the Company shall transfer to the holder of this Warrant Certificate appropriate evidence of ownership of the shares of Common Stock or other securities or property (including any money) to which the holder is entitled, registered or otherwise placed in, or payable to the order of, the name or names of the holder or such transferee as may be directed in writing by the holder, and shall deliver such evidence of ownership and any other securities or property (including any money) to the Person or Persons entitled to receive the same, together with an amount in cash in lieu of any fraction of a share.

        (d)  In connection with payment of the Exercise Price with shares of Preferred Stock, the Company may require that at the time of such exercise it receive representations and warranties from the applicable holder of the Warrants regarding such holder's title to the Preferred Stock and the lack

Exh. 2-2

of encumbrances thereon. If the Company is unable to consummate an exercise of Warrants through payment of the Exercise Price with shares of Preferred Stock because of any limitations contained or construed in the Delaware General Corporation Law, the Company shall use its best efforts to take all such action as may be necessary to place the Company in a position to do so. In the event the Company, after the taking of any action by it as contemplated above, is unable to consummate such exercise, the Company shall accept such number of shares of Preferred Stock in payment as it shall then be authorized to do so under the Delaware General Corporation Law.

        (e)  The Company shall not be required to issue a fractional share of Common Stock upon the exercise of Warrants. As to any fraction of a share which the Warrant holder would otherwise be entitled to purchase upon such exercise, the Company may pay a cash adjustment in respect of such fraction in an amount equal to the same fraction of the Price per share of Common Stock on the date of exercise.

        Section 2.    Antidilution Adjustments.    The shares of Common Stock purchasable on exercise of the Warrants are shares of Common Stock as constituted as of the Issuance Date. The number and kind of securities purchasable upon the exercise of the Warrants, and the Exercise Price, shall be subject to adjustment from time to time upon the happening of certain events, as follows:

        (a)    Mergers, Consolidations and Reclassifications.    In case of any reclassification or change of outstanding securities issuable upon exercise of the Warrants at any time after the Issuance Date (other than a change in par value, or from par value to no par value, or from no par value to par value or as a result of a subdivision or combination to which Section 2(b) applies), or in case of any consolidation or merger of the Company with or into any entity or other person (other than a merger with another entity or other person in which the Company is the surviving corporation and which does not result in any reclassification or change in the securities issuable upon exercise of this Warrant Certificate), the holder of the Warrants shall have, and the Company, or such successor corporation or other entity, shall covenant in the constituent documents effecting any of the foregoing transactions that such holder does have the right to obtain, upon the exercise of the Warrants, in lieu of each share of Common Stock, other securities, money or other property theretofore issuable upon exercise of a Warrant, the kind and amount of shares of stock, other securities, money or other property receivable upon such reclassification, change, consolidation or merger by a holder of the shares of Common Stock, other securities, money or other property issuable upon exercise of a Warrant if the Warrants had been exercised immediately prior to such reclassification, change, consolidation or merger. The constituent documents effecting any such reclassification, change, consolidation or merger shall provide for adjustments which shall be as nearly equivalent as may be practicable to the adjustments provided in this Section 2(a). The provisions of this Section 2(a) shall similarly apply to successive reclassifications, changes, consolidations or mergers.

        (b)    Subdivisions and Combinations.    If the Company, at any time after the Issuance Date, shall subdivide its shares of Common Stock into a greater number of shares, the Exercise Price in effect immediately prior to such subdivision shall be proportionately reduced, and the number of shares of Common Stock purchasable upon exercise of the Warrants shall be proportionately increased, as at the effective date of such subdivision, or if the Company shall take a record of holders of its Common Stock for such purpose, as at such record date, whichever is earlier. If the Company, at any time after the Issuance Date, shall combine its shares of Common Stock into a smaller number of shares, the Exercise Price in effect immediately prior to such combination shall be proportionately increased, and the number of shares of Common Stock purchasable upon exercise of the Warrants shall be proportionately reduced, as at the effective date of such combination, or if the Company shall take a record of holders of its Common Stock for purposes of such combination, as at such record date, whichever is earlier.

Exh. 2-3

        (c)    Dividends and Distributions.    If the Company at any time after the Issuance Date shall declare a dividend on its Common Stock payable in stock or other securities of the Company to the holders of its Common Stock, the holder of this Warrant Certificate shall, without additional cost, be entitled to receive upon any exercise of a Warrant, in addition to the Common Stock to which such holder would otherwise be entitled upon such exercise, the number of shares of stock or other securities which such holder would have been entitled to receive if he had been a holder immediately prior to the record date for such dividend (or, if no record date shall have been established, the payment date for such dividend) of the number of shares of Common Stock purchasable on exercise of such Warrant immediately prior to such record date or payment date, as the case may be.

        (d)    Certain Issuances of Securities.    Subject to Section 2(f), if the Company at any time after the Issuance Date shall issue any additional shares of Common Stock (otherwise than as provided in subsections (a) through (c) of this Section 2) at a price per share less than the Average Price per share of Common Stock for the 20 trading days immediately preceding the date of the authorization of such issuance (the "Market Price") by the Board of Directors or its compensation committee (as applicable), then the Exercise Price upon each such issuance shall be adjusted to that price determined by multiplying the Exercise Price by a fraction:

            i.  the numerator of which shall be the sum of (1) the number of shares of Common Stock outstanding immediately prior to the issuance of such additional shares of Common Stock multiplied by the Market Price, and (2) the consideration, if any, received by the Company upon the issuance of such additional shares of Common Stock, and

          ii.  the denominator of which shall be the Market Price multiplied by the total number of shares of Common Stock outstanding immediately after the issuance of such additional shares of Common Stock.

No adjustments of the Exercise Price shall be made under this Section 2(d) upon the issuance of any additional shares of Common Stock that (v) are issued pursuant to any grant or award made prior to the Issuance Date under any thrift plan, stock purchase plan, stock bonus plan, stock option plan, employee stock ownership plan, incentive or profit sharing arrangement or other benefit or compensation plan for the benefit of the Company's officers, directors and/or employees ("Employee Benefit Plans") that has been approved by the Board of Directors of the Company or its compensation committee and that otherwise would cause an adjustment under this Section 2(d); (w) are issued pursuant to any grant or award made on or after the Issuance Date under any Employee Benefit Plan if the "Market Price" of any such issuance is not less than the lesser of the Market Price as determined above and the "Fair Market Value", as defined under the applicable Employee Benefit Plan, on the date of Board or compensation committee authorization); (x) are issued pursuant to any Common Stock Equivalent (as hereinafter defined) (i) if upon the issuance of any such Common Stock Equivalent, any such adjustments shall previously have been made pursuant to Section 2(e), (ii) if no adjustment was required pursuant to Section 2(e), or (iii) if such Common Stock Equivalent was issued prior to this Warrant Certificate; (y) are issued pursuant to a public offering by the Company; or (z) results in an adjustment pursuant to Section 2(f).

        (e)    Common Stock Equivalents.

            i.  Subject to Section 2(f), if the Company shall, after the Issuance Date, issue any security or evidence of indebtedness which is convertible into or exchangeable for Common Stock ("Convertible Security"), or any warrant, option or other right to subscribe for or purchase Common Stock or any Convertible Security, other than pursuant to Employee Benefit Plans (together with Convertible Securities, "Common Stock Equivalent"), then the Exercise Price upon each such issuance shall be adjusted as provided in Section 2(d) on the basis that (i) the maximum number of additional shares of Common Stock issuable pursuant

Exh. 2-4

to all such Common Stock Equivalents shall be deemed to have been issued as of the date of issuance of such Common Stock Equivalent; and (ii) the aggregate consideration for such maximum number of additional shares of Common Stock shall be deemed to be the minimum consideration received and receivable by the Company for the issuance of such additional shares of Common Stock pursuant to such Common Stock Equivalent.

          ii.  Notwithstanding the foregoing, no adjustment shall be made pursuant to this Section 2(e) unless the consideration received and receivable by the Company per share of Common Stock for the issuance of such additional shares of Common Stock pursuant to such Common Stock Equivalent is less than the Market Price. No adjustment of the Exercise Price shall be made under this Section 2(e) upon the issuance of any Convertible Security which is issued pursuant to the exercise of any warrants or other subscription or purchase rights therefor, if any adjustment shall previously have been made in the Exercise Price then in effect upon the issuance of such warrants or other rights pursuant to this Section 2(e). No adjustment shall be made under this Section 2(e) if an adjustment is to be made under Section 2(f). No adjustment shall be made as a result of adjustment in the exercise or conversion price of Common Stock Equivalents, if those adjustments occur by the terms of such Common Stock Equivalents.

        (f)    Special Adjustments of Exercise Price.    Notwithstanding anything to the contrary in Section 2(d) or Section 2(e), this Section 2(f) shall govern adjustments to the Exercise Price for the transactions described in this Section 2(f) .

            i.  If the Company at any time after the Issuance Date and prior to the second anniversary of the Issuance Date shall issue any additional shares of Common Stock (otherwise than as provided in subsections (a) through (c) of Section 2; pursuant to any Employee Benefit Plan; pursuant to any Common Stock Equivalent outstanding as of the Issuance Date; or pursuant to a public offering) or upon the issuance of any such Common Stock for which any adjustments shall previously have been made pursuant to Section 2(e) or Section 2(f)(ii); and the New Stock Issue Price (defined below) of such additional shares is less than the Exercise Price then in effect, then the Exercise Price upon each such issuance shall be adjusted to the New Stock Issue Price of such additional shares. The "New Stock Issuance Price" shall be determined by dividing the total amount of consideration received by the Company for such issue or sale by the number of shares of Common Stock issued or sold.

          ii.  If the Company at any time after the Issuance Date and prior to the second anniversary of the Issuance Date, issues any Common Stock Equivalent (which by definition excludes Employee Benefit Plan securities) (otherwise than as provided in subsections (a) through (c) of Section 2; or pursuant to any Common Stock Equivalent outstanding as of the Issuance Date) and the New CSE Exercise Price (defined below) of such Common Stock Equivalents is less than the Exercise Price then in effect, then the Exercise Price upon each such issuance shall be adjusted to the New CSE Exercise Price of such Common Stock Equivalents. The "New CSE Exercise Price" shall be determined by dividing (x) the total amount, if any, received or receivable by the Company as consideration for the issuance of such Common Stock Equivalents, plus the minimum aggregate amount of additional consideration payable to the Company upon the exercise, conversion or exchange of such Common Stock Equivalents, plus, in the case of any such Common Stock Equivalents which relate to Convertible Securities, the minimum aggregate amount of additional consideration, if any, payable to the Company upon the conversion or exchange of such Convertible Securities, by (y) the total maximum number of shares of Common Stock issuable upon the exercise, conversion or exchange of all such Common Stock Equivalents.

Exh. 2-5

        (g)    Miscellaneous.    The following provisions shall be applicable to the making of adjustments in the Exercise Price hereinbefore provided in this Section 2:

            i.  The consideration received by the Company shall be deemed to be the following: (I) to the extent that any additional shares of Common Stock or any Common Stock Equivalent shall be issued for cash consideration, the consideration received by the Company therefor, or, if such additional shares of Common Stock or Common Stock Equivalent are offered by the Company for subscription, the subscription price, or, if such additional shares of Common Stock or Common Stock Equivalent are sold to underwriters or dealers for public offering without a subscription offering, the initial public offering price, in any such case excluding any amounts paid or receivable for accrued interest or accrued dividends and without deduction of any compensation, discounts, commissions or expenses paid or incurred by the Company for and in the underwriting of, or otherwise in connection with, the issue thereof; (II) to the extent that such issuance shall be for a consideration other than cash, then, except as herein otherwise expressly provided, the fair value of such consideration at the time of such issuance as determined in good faith by the Company's Board of Directors, as evidenced by a certified resolution of the Board of Directors delivered to the holder of this Warrant Certificate setting forth such determination. The consideration for any additional shares of Common Stock issuable pursuant to any Common Stock Equivalent shall be the consideration received by the Company for issuing such Common Stock Equivalent, plus the additional consideration payable to the Company upon the exercise, conversion or exchange of such Common Stock Equivalent. In case of the issuance at any time of any additional shares of Common Stock or Common Stock Equivalent in payment or satisfaction of any dividend upon any class of stock other than Common Stock, the Company shall be deemed to have received for such additional shares of Common Stock or Common Stock Equivalent (which shall not be deemed to be a dividend payable in, or other distribution of, Common Stock under Section 2(c) above) consideration equal to the amount of such dividend so paid or satisfied. In the event additional shares of Common Stock or Common Stock Equivalents are issued together with other shares or securities or other assets of the Company or its subsidiaries for consideration which covers both, the consideration for such shares of Common Stock and Common Stock Equivalents shall be computed based on the respective portions of such consideration so received, computed as provided in this Section 2(g)i., as determined and allocated in good faith by the Board of Directors of the Company.

          ii.  Upon the expiration of the right to convert, exchange or exercise any Common Stock Equivalent the issuance of which effected an adjustment in the Exercise Price, if any such Common Stock Equivalent shall not have been converted, exercised or exchanged, the number of shares of Common Stock deemed to be issued and outstanding because they were issuable upon conversion, exchange or exercise of any such Common Stock Equivalent shall no longer be computed as set forth above, and the Exercise Price shall forthwith be readjusted and thereafter be the price which it would have been (but reflecting any other adjustments in the Exercise Price made pursuant to the provisions of Section 2(d) after the issuance of such Common Stock Equivalent) had the adjustment of the Exercise Price made upon the issuance or sale of such Common Stock Equivalent been made on the basis of the issuance only of the number of additional shares of Common Stock actually issued upon exercise, conversion or exchange of such Common Stock Equivalent and thereupon only the number of additional shares of Common Stock actually so issued shall be deemed to have been issued and only the consideration actually received by the Company (computed as in this Section 2(f)(i)) shall be deemed to have been received by the Company.

Exh. 2-6

          iii.  The number of shares of Common Stock at any time outstanding shall not include any shares thereof then directly or indirectly owned or held by or for the account of the Company or its wholly owned subsidiaries.

          iv.  Upon each adjustment of the Exercise Price as a result of the calculations made in Section 2(d), (e) and (f) hereof, this Warrant shall thereafter evidence the right to purchase, at the adjusted Exercise Price, that number of shares of Common Stock obtained by (i) multiplying the number of shares covered by this Warrant immediately prior to such adjustment of the number of shares by the Exercise Price in effect immediately prior to such adjustment of the Exercise Price and (ii) dividing the product so obtained by the Exercise Price in effect immediately after such adjustment of the Exercise Price.

          v.  For the purpose of this Section 2, the term "shares of Common Stock" shall mean shares of (i) the class of stock designated as the Common Stock at the date hereof or (ii) any other class of stock resulting from successive changes or reclassifications of such shares consisting solely of changes in par value, or from par value to no par value, or from no par value to par value. If at any time, because of an adjustment pursuant to Section 2(a), the Warrants shall entitle the holders to purchase any securities other than shares of Common Stock, thereafter the number of such other securities so purchasable upon exercise of each Warrant and the Exercise Price of such securities shall be subject to adjustment from time to time in a manner and on terms as nearly equivalent as practicable to the provisions with respect to the Common Stock contained in this Section 2.

        (h)    Calculation of Exercise Price.    The Exercise Price in effect from time to time shall be calculated to four decimal places and rounded to the nearest thousandth.

        (i)    Shareholder Approval.    Notwithstanding anything to the contrary herein, any provision hereof providing for adjustments to the Exercise Price that would require shareholder approval pursuant to the Nasdaq Market Rules shall be subject to the Company's obtaining such requisite approval.

Exh. 2-7

        Section 3.    Notice of Adjustments.    Whenever the Exercise Price or the number of shares of Common Stock is required to be adjusted as provided in Section 2, the Company shall forthwith compute the adjusted Exercise Price or the number of shares of Common Stock issuable and shall prepare and mail to the holder hereof a certificate setting forth such adjusted Exercise Price or such number of shares of Common Stock, showing in reasonable detail the facts upon which the adjustment is based.

        Section 4.    Voluntary Reduction.    (a) The Company may at its option, but shall not be obligated to, at any time during the term of the Warrants, reduce the then current Exercise Price by any amount selected by the Board of Directors; provided that if the Company elects so to reduce the then current Exercise Price, such reduction shall be irrevocable during its effective period and remain in effect for a minimum of 30 days following the date of such election, after which time the Company may, at its option, reinstate the Exercise Price in effect prior to such reduction. Whenever the Exercise Price is reduced, the Company shall mail to the holder a notice of the reduction at least 30 days before the date the reduced Exercise Price takes effect, stating the reduced Exercise Price and the period for which such reduced Exercise Price will be in effect.

        (b)  The Company may make such decreases in the Exercise Price, in addition to those required or allowed by this Section 4, as shall be determined by it, as evidenced by a certified resolution of the Board of Directors delivered to the holders, to be advisable to avoid or diminish any income tax to the holder resulting from any dividend or distribution of stock or issuance of rights or warrants to purchase or subscribe for stock or from any event treated as such for income tax purposes.

        Section 5.    Mandatory Exercise.

        (a)  If (i) the Price of the Common Stock averages at least 150% of the Exercise Price (as adjusted to reflect any stock split, combination, reclassification, recapitalization, exchange, stock dividend or other distribution payable in Common Stock with respect to shares of Common Stock) for sixty (60) consecutive trading days in the principal market in which the Common Stock is traded and (ii) the Company gives written notice pursuant to Section 10 hereof (the "Company Notice") to the holder hereof of the satisfaction of the condition in clause (i) within thirty (30) days after the expiration of the relevant 60-day-trading period, then (x) within ten (10) days after the Company Notice, the holder shall notify the Company whether the holder will pay all of the Exercise Price by delivery of Preferred Stock in accordance with Section 1(a)(ii)(2), and (y) within fifteen (15) days after the Company Notice, the holder hereof shall exercise all of the Warrants. If the Company gives the Company Notice on a timely basis within the Exercise Deferral Period, and the exercise of the Warrants pursuant to the foregoing would otherwise occur during the Exercise Deferral Period, then the exercise of the Warrants shall be deferred until no later than the third Business Day (as defined in the Securities Purchase Agreement) following the expiration of the Exercise Deferral Period (the "Deferred Exercise Date"). If required by this Section 5, the holder hereof agrees to exercise the Warrants, and to purchase shares of Common Stock pursuant to the terms of this Warrant Certificate. If the holder has not fulfilled its obligations to exercise the Warrants pursuant to this Section 5 within fifteen (15) days after the holder's receipt of the Company Notice or by the Deferred Exercise Date, as applicable, then (without limiting the Company's available remedies) (A) the obligations of holder under this Section 5 shall continue but the purchase rights otherwise represented by this Warrant Certificate shall terminate, (B) the Company may thereafter refuse, in its sole discretion, to allow holder to exercise the Warrants (including pursuant to this Section 5), (C) all obligations of the Company under Sections 3, 6, 7 and 8 shall terminate, (D) no further adjustments to the Exercise Price shall be made unless the Company in its sole discretion consents in writing. Each Warrant holder's obligations under this Section 5(a) shall be subject to the expiration or termination of all waiting periods (and any extensions thereof) applicable to exercise of such holder's Warrants under the HSR Act (as defined below); provided that such holder shall have certified in writing to the Company that a

Exh. 2-8

filing under the HSR Act is required and provided further that such holder shall use its best efforts to cause the expiration or termination of such waiting period to occur as promptly as practicable.

        (b)  Holder represents and warrants to the Company that holder has full corporate power and authority to execute, deliver, and perform this Warrant Certificate and to consummate the transactions contemplated hereby. The execution, delivery, and performance by holder of this Warrant Certificate have been duly authorized by all necessary corporate action of holder. This Warrant Certificate has been duly executed and delivered by holder and constitutes a valid and legally binding obligation of holder, enforceable against holder in accordance with its terms, except that such enforceability may be limited by (i) applicable bankruptcy, insolvency, reorganization, moratorium, and similar laws affecting creditors' rights generally and (ii) general equitable principles (regardless of whether such enforceability is considered in a proceeding in equity or at law).

        (c)  The right to require exercise of the Warrants is hereby declared by the parties hereto to be a unique right, the loss of which is not readily susceptible to monetary quantification. Consequently, the parties hereto agree that an action for specific performance of the exercise and purchase obligations created by this Section 5 is an available remedy for the breach of the provisions of this Section 5. If the Company is forced to institute legal proceedings to enforce its rights in accordance with the provisions of this Section 5, it shall be entitled to recover its reasonable attorneys' fees and court costs incurred in enforcing such rights.

        (d)  Holder is executing this Warrant Certificate in order to make and agree to the covenants, representations and warranties of holder contained in this Section 5, which shall be binding upon the holder's successors and assigns.

        Section 6.    Notices to Warrant Holders.    In the event:

        (a)  the Company shall authorize any consolidation or merger to which the Company is a party and for which approval of any stockholders of the Company is required, or of the conveyance or sale of all or substantially all of the assets of the Company, or of any reclassification or change of the Common Stock or other securities issuable upon exercise of the Warrants (other than a change in par value, or from par value to no par value, or from no par value to par value or as result of a subdivision or combination), or a tender offer or exchange offer for shares of Common Stock (or other securities issuable upon the exercise of the Warrants); or

        (b)  the Company shall declare any dividend (or any other distribution) on the Common Stock or any other class of its capital stock, other than dividends on the Shares, as defined in the Securities Purchase Agreement; or

        (c)  the Company shall authorize the granting to the holders of Common Stock or any other class of its capital stock of rights or warrants to subscribe for or purchase any shares of any class or series of capital stock or any other securities convertible into or exchangeable for shares of stock; or

        (d)  of the voluntary or involuntary dissolution, liquidation or winding up of the Company; then the Company shall cause to be sent to the holder hereof, at least 30 days prior to the applicable record date hereinafter specified, or promptly in the case of events for which there is no record date, a written notice stating (x) the date for the determination of the holders of record of shares of Common Stock (or other securities issuable upon the exercise of the Warrants) entitled to receive any such dividends or other distribution, (y) the initial expiration date set forth in any tender offer or exchange offer for shares of Common Stock (or other securities issuable upon the exercise of the Warrants), or (z) the date on which any of the events specified in subsections (a)-(d) is expected to become effective or consummated, and the date as of which it is expected that holders of record of shares of Common Stock (or other securities issuable upon the exercise of the Warrants) shall be entitled to exchange such shares for securities or other property, if any,

Exh. 2-9

deliverable upon any such event. Failure to give such notice or any defect therein shall not affect the legality or validity of any such event, or the vote upon any such action.

        Section 7.    Reports to Warrant Holders.    The Company will cause to be delivered, by first-class mail, postage prepaid, to holder at such holder's address appearing hereon, or such other address as the holder shall specify, a copy of any reports delivered by the Company to the holders of Common Stock.

        Section 8.    Covenants of the Company.    The Company covenants and agrees that:

        (a)  Until the Expiration Date, the Company shall at all times reserve and keep available, out of the aggregate of its authorized but unissued Common Stock (and other securities), for the purpose of enabling it to satisfy any obligation to issue shares of Common Stock (and other securities) upon the exercise of the Warrants, the number of shares of Common Stock (and other securities) issuable upon the exercise of such Warrants.

        (b)  The Company shall pay all expenses, taxes and other charges payable in connection with the preparation, issuance and delivery of new warrant certificates on transfer of the Warrants.

        (c)  All Common Stock (and other securities) which may be issued upon exercise of the Warrants shall upon issuance be validly issued, fully paid, non-assessable and free from all preemptive rights and all taxes, liens and charges with respect to the issuance thereof, and will not be subject to any restrictions on voting or transfer thereof except as set forth in the Securities Purchase Agreement, any stockholders agreement and except for restrictions arising under state or federal securities laws.

        (d)  All original issue taxes payable in respect of the issuance of shares of Common Stock to the registered holder hereof upon the exercise of the Warrants shall be borne by the Company; provided, that the Company shall not be required to pay any tax or charge imposed in connection with any transfer involved in the issuance of any certificates representing shares of Common Stock (and other securities) in any name other than that of the registered holder hereof, and in such case the Company shall not be required to issue or deliver any certificate representing shares of Common Stock (and other securities) until such tax or other charge has been paid or it has been established to the Company's satisfaction that no such tax or charge is due.

        (e)  As soon as practicable after the receipt from the holder of this Warrant Certificate of notice of the intent to exercise of a number of warrants sufficient to require a filing under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 and the rules, regulations and formal interpretations thereunder, as amended from time to time (the "HSR Act") (and after the receipt, if applicable, of the notice referred to in Rule 803.5 of the HSR Act), but in any event no later than the 15th business day after receipt of such notice(s), the Company will (i) if required by the HSR Act, prepare and file with Antitrust Division of the Department of Justice (the "DOJ") and the Federal Trade Commission (the "FTC") the Notification and Report Form (accompanied by all documentary attachments contemplated thereby) required by the HSR Act, (ii) upon request of the holder, request early termination of the waiting period imposed by the HSR Act, and (iii) coordinate and cooperate with the holder in responding to formal and informal requests for additional information and documentary material from the DOJ and the FTC in connection with such filing. Notwithstanding the foregoing, if the holder is required to file with the DOJ and FTC the Notification and Report Form solely as a result of its holding and/or purchasing shares of Common Stock issued pursuant to this Warrant (with no regard to any other securities held by such holder or its affiliates) and the holder certifies such fact to the Company in writing, the Company agrees to promptly reimburse the holder for all fees and expenses for the preparation and filing of such form, including all legal expenses and filing fees.

Exh. 2-10

        (f)    The Company will not change the par value of the Common Stock from par value $0.01 per share to any higher par value which exceeds the Exercise Price then in effect, and will reduce the par value of the Common Stock upon any event described in Section 2 that would, but for this provision, reduce the Exercise Price below the par value of the Common Stock.

        Section 9.    No Rights as Stockholder.    The holder of the Warrants shall not, by virtue of holding such Warrants, be entitled to any rights of a stockholder of the Company either at law or in equity, and the rights of the holder of the Warrants are limited to those expressed herein.

        Section 10.    Notices.    All notices, requests, demands, and other communications required or permitted to be given or made hereunder by any party hereto shall be in writing and shall be deemed to have been duly given or made if (i) delivered personally, (ii) sent by prepaid overnight courier service, or (iii) sent by telecopy or facsimile transmission, answer back requested, to the parties at the following addresses (or at such other addresses as shall be specified by the parties by like notice):

if to the holder:

Global Energy Partners
1100 Louisiana Street
Houston, Texas 77002
Fax: 713-890-1429
Attn: Steven A. Webster

and

CSFB Private Equity
11 Madison Avenue
New York, New York 10010
Fax: 917-326-8076
Attn: Ivy Dodes

with a copy to:

Gardere Wynne Sewell LLP
1000 Louisiana, Suite 3400
Houston, Texas 77002
Attention: N.L. Stevens III
Telefax: 713-276-5807

and if to the Company:

Brigham Exploration Company
6300 Bridge Point Parkway
Building 2, Suite 500
Austin, Texas 78730
Attention: Chief Financial Officer
Telecopier: (512) 472-3400

Such notices, requests, demands, and other communications shall be effective (i) if delivered personally or sent by courier service, upon actual receipt by the intended recipient, or (ii) if sent by telecopy or facsimile transmission, when the answer back is received.

        Section 11.    Governing Law.    This Warrant Certificate shall be governed by and construed in accordance with the laws of the State of New York without regard to principles of conflict of laws.

        Section 12.    Lost, Stolen, Mutilated or Destroyed Warrant Certificates.    Upon receipt by the Company of evidence reasonably satisfactory to it of the ownership of and the loss, theft, destruction or

Exh. 2-11

mutilation of any Warrant Certificate, then, in the absence of notice to the Company that such Warrant Certificate has been acquired by a bona fide purchaser, the Company shall execute and deliver, in exchange for or in lieu of the lost, stolen, destroyed or mutilated Warrant Certificate, a substitute Warrant Certificate of the same tenor and evidencing a like number of Warrants.

        Section 13.    Transfer.    Subject to Section 14 hereof and to the Securities Purchase Agreement, transfer of Warrants, in whole or in part, shall be registered on the books of the Company to be maintained for such purposes, upon surrender of the Warrant Certificate representing such Warrants at the principal office of the Company referred to in Section 10, together with a written assignment substantially in the form of Exhibit B to this Warrant Certificate and a written agreement, in form reasonably satisfactory to the Company, setting forth the new Warrant holder's agreement to be bound by all of the terms of this Warrant Certificate (including without limitation Section 14) and by Section 5.5 of the Securities Purchase Agreement, each duly executed by the holder, and funds sufficient to pay any transfer taxes payable by such holder upon the making of such transfer. Upon such surrender and, if required, such payment, the Company shall execute and deliver a new Warrant Certificate or Warrant Certificates in the name of the assignee or assignees and in the denomination specified in such instrument of assignment, and shall issue to the assignor a new Warrant Certificate or Warrant Certificates evidencing the portion of the old Warrant Certificate not so assigned, and the old Warrant Certificate shall promptly be canceled.

        Section 14.    Restrictions on Transferability.    The Warrant Certificate represents Warrants referred to in the Securities Purchase Agreement. Said Securities Purchase Agreement is hereby incorporated by reference in and made a part of this instrument and is hereby referred to for a description of certain limitations of rights, obligations, duties and immunities thereunder of the Company and the holders, and in the event of any conflict between the terms of this Warrant Certificate and the provisions of the Securities Purchase Agreement, the provisions of the Securities Purchase Agreement shall control.

        Section 15.    Severability.    If any provision of this Warrant Certificate is held to be unenforceable, then this Warrant Certificate shall be considered divisible and such provision shall be deemed inoperative to the extent it is deemed unenforceable, and in all other respects this Warrant Certificate shall remain in full force and effect to the maximum extent permitted by Applicable Law (as defined in the Securities Purchase Agreement).

Exh. 2-12

        IN WITNESS WHEREOF, the Company has caused this Warrant Certificate to be executed as of December 20, 2002, by the undersigned, thereunto duly authorized.

			BRIGHAM EXPLORATION COMPANY
			By:	/s/  DAVID T. BRIGHAM David T. Brigham Executive Vice President Land & Administration
DLJ MERCHANT BANKING PARTNERS III, L.P.
By:	DLJ MERCHANT BANKING III, INC., its Managing General Partner
	By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact

Exh. 2-13

EXHIBIT A

ELECTION TO EXERCISE

[To be executed on exercise of the Warrant evidenced by this Warrant Certificate pursuant to Section 1(a)]

TO: Brigham Exploration Company

        The undersigned, the holder of the Warrants evidenced by the attached Warrant Certificate, hereby irrevocably elects to exercise                        of such Warrants, and herewith makes payment of                        representing the aggregate Exercise Price thereof, and requests that the certificate representing the securities issuable hereunder be issued in the name of                         and delivered to                        , whose address is                        .

        The Exercise Price is being paid by bank draft or cashier's check.

Dated:

Name of Registered Holder:

Signature:

Title:

Address:

Notice: The above signature(s) must correspond with the name as written on the face of the Warrant Certificate in every detail, without alteration or enlargement or any change whatsoever.

Exh. 2-14

EXHIBIT B

ASSIGNMENT FORM

        FOR VALUE RECEIVED the undersigned registered owner of the attached Warrant Certificate hereby sells, assigns and transfers unto the assignee named below all of the rights of the undersigned under this Warrant Certificate, with respect to the number of shares of Common Stock set forth below:

Name and Address of Assignee:

No. of Shares of
Common Stock

and does hereby irrevocably constitute and appoint                                                 attorney-in-fact to register such transfer on the books of Brigham Exploration Company maintained for that purpose, with full power of substitution in the premises.

Dated:

Name:

Signature:

Witness:

        The assignee named above hereby agrees to purchase and take the attached Warrant Certificate pursuant to and in accordance with the terms and conditions of the Warrant Certificate and Section 5.5 of the Securities Purchase Agreement, dated as of December     , 2002, between Brigham Exploration Company and the initial holder named therein and agrees to be bound thereby.

Dated:

Name:

Signature:

Exh. 2-15

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EXHIBIT 2

EXHIBIT A ELECTION TO EXERCISE [To be executed on exercise of the Warrant evidenced by this Warrant Certificate pursuant to Section 1(a)]
EXHIBIT B ASSIGNMENT FORM

EX-3

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EXHIBIT 3

SECOND AMENDMENT TO
REGISTRATION RIGHTS AGREEMENT

        This Second Amendment to Registration Rights Agreement (this "Amendment") is entered into as of December 21, 2002, by and among Brigham Exploration Company, a Delaware corporation (the "Company"), and the Credit Suisse First Boston entities listed on Schedule A hereto (the "CSFB Entities").

RECITALS

        WHEREAS, pursuant to that certain Registration Rights Agreement, dated as of November 1, 2000 (the "Agreement"), by and among the Company, DLJMB Funding III, Inc., a Delaware corporation, and DLJ ESC II, L.P., a Delaware limited partnership (collectively, the "November 2000 Investors"), the Company provided certain registration rights to the November 2000 Investors regarding shares of the Company's common stock issuable upon exercise of warrants issued by the Company to the November 2000 Investors;

        WHEREAS, pursuant to that certain First Amendment to Registration Rights Agreement, dated March 5, 2001 (the "March 2002 Amendment"), by and among the Company, each of the November 2000 Investors, DLJ Merchant Banking Partners III, L.P., a Delaware limited partnership, and DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III, C.V., a Netherlands Antilles limited partnership (collectively, the "March 2001 Investors"), the Company provided certain registration rights under the Agreement to the March 2001 Investors regarding shares of the Company's common stock issuable upon exercise of warrants issued by the Company to the March 2001 Investors;

        WHEREAS, each of the November 2000 Investors is a party to a certain Warrant Certificate (the "November 2000 Warrant Certificates"), dated as of November 1, 2000, by and between the Company and such investor;

        WHEREAS, each of the March 2001 Investors is a party to a certain Warrant Certificate (the "March 2001 Warrant Certificates"), dated as of March 5, 2001, by and between the Company and such investor;

        WHEREAS, each of DLJ Merchant Banking Partners III, L.P., a Delaware limited partnership; DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III, C.V., a Netherlands Antilles limited partnership; DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-1, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-1, C.V., a Netherlands Antilles limited partnership; DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-2, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-2, C.V., a Netherlands Antilles limited partnership; DLJ MB PartnersIII GmbH & Co. KG, a German limited partnership; Millennium Partners II, L.P., a Delaware limited partnership; and MBP III Plan Investors, L.P., a Delaware limited partnership (collectively, the "December 2002 Investors, and together with the November 2000 Investors and the March 2001 Investors, the "Investors") is a party to a certain Warrant Certificate (the "December 2002 Warrant Certificates," and together with the November 2000 Warrant Certificates and the March 2001 Warrant Certificates, the "Warrant Certificates"), dated as of December 20, 2002, by and between the Company and such investor;

Exh. 3-1

        WHEREAS, the December 2002 Warrant Certificates were executed and delivered in connection with the consummation of transactions contemplated by that certain Securities Purchase Agreement, dated December 20, 2002, by and among the Company and the December 2002 Investors;

        WHEREAS, pursuant to the Warrant Certificates, each Holder (as defined in the Agreement) has been issued a warrant (the "Warrant") to purchase shares of the Company's common stock, par value $0.01 per share (the "Company's Common Stock");

        WHEREAS, the December 2002 Investors and Shell Capital Inc. ("SCI") are parties to that certain Assignment Agreement, dated as of November 21, 2002 (the "Assignment Agreement"), whereby the December 2002 Investors have purchased from SCI a note payable by Brigham Oil & Gas, L.P. in the principal amount of $10,000,000 (the "Note") that is convertible into 2,564,102 shares of the Company's Common Stock;

        WHEREAS, the Company and the December 2002 Investors are parties to that certain Omnibus Agreement, dated as of December 20, 2002 (the "Omnibus Agreement"), whereby the December 2002 Investors have converted the Note into 2,564,102 shares of the Company's Common Stock; and

        WHEREAS, to induce the Investors to enter into the Warrant Certificates, the Securities Purchase Agreement, and the Omnibus Agreement, the Company has agreed to provide registration rights with respect to the shares issuable upon exercise of the Warrants and upon conversion under the Omnibus Agreement;

        NOW, THEREFORE, for and in consideration of the foregoing, and other good and valuable consideration, the sufficiency of which are hereby acknowledged, the parties hereto, intending to be legally bound, do hereby agree as follows:

        1.    Amendments.

        (a)  The "RECITALS" section of the Agreement is amended by deleting such section entirely and replacing it with the following:

        "WHEREAS, each of DLJMB Funding III, Inc. ("MB") and DLJ ESC II, L.P. ("ESC") (MB and ESC are sometimes referred to collectively as the "November 2000 Investors") is a party to a certain Warrant Certificate (the "November 2000 Warrant Certificates"), dated as of November 1, 2000, by and between the Company and such investor;

        WHEREAS, each of the November 2000 Investors, DLJ Merchant Banking Partners III, L.P. ("MBP") and DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III, C.V. ("DOP") (the November 2000 Investors, MBP and DOP are sometimes referred to collectively as the "March 2001 Investors") is a party to a certain Warrant Certificate (the "March 2001 Warrant Certificates"), dated as of March 5, 2001, by and between the Company and such investor;

        WHEREAS, each of MBP; DOP; DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-1, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-1, C.V. ("DOP-1"); DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-2, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-2, C.V. ("DOP-2"); DLJ MB PartnersIII GmbH & Co. KG ("MBP GmbH"); Millennium Partners II, L.P. ("MPII"); and MBP III Plan Investors, L.P. ("MPIII") (MBP, DOP, DOP-1, DOP-2, MBP GmbH, MPII and MPIII are sometimes referred to collectively as the "December 2002 Investors," and together with the November 2000 Investors and the March 2001 Investors, the "Investors") is a party to a certain Warrant Certificate (the "December 2002 Warrant Certificates," and together with the November 2000 Warrant Certificates

Exh. 3-2

and the March 2001 Warrant Certificates, the "Warrant Certificates"), dated as of December 20, 2002, by and between the Company and such investor;

        WHEREAS, the November 2000 Warrant Certificates were executed and delivered to the November 2000 Investors in connection with the consummation of transactions contemplated by that certain Securities Purchase Agreement, dated as of November 1, 2000, by and among the Company and the November 2000 Investors;

        WHEREAS, the March 2001 Warrant Certificates were executed and delivered in connection with the consummation of transactions contemplated by that certain Securities Purchase Agreement, dated as of March 5, 2001, by and among the Company and the March 2001 Investors;

        WHEREAS, the December 2002 Warrant Certificates were executed and delivered in connection with the consummation of transactions contemplated by that certain Securities Purchase Agreement, dated December 20, 2002, by and among the Company and the December 2002 Investors;

        WHEREAS, pursuant to the Warrant Certificates, each Holder (as defined in the Agreement) has been issued a warrant (the "Warrant") to purchase shares of the Company's common stock, par value $0.01 per share (the "Company's Common Stock");

        WHEREAS, the December 2002 Investors and Shell Capital Inc. ("SCI") are parties to that certain Assignment Agreement, dated as of November 21, 2002 (the "Assignment Agreement"), whereby the December 2002 Investors have purchased from SCI a note payable by Brigham Oil & Gas, L.P. in the principal amount of $10,000,000 (the "Note") that is convertible into 2,564,102 shares of the Company's Common Stock;

        WHEREAS, the Company and the December 2002 Investors are parties to that certain Omnibus Agreement, dated as of December 20, 2002 (the "Omnibus Agreement"), whereby the December 2002 Investors have converted the Note into 2,564,102 shares of the Company's Common Stock; and

        WHEREAS, to induce the Investors to enter into the Warrant Certificates, the Securities Purchase Agreement, and the Omnibus Agreement, the Company has agreed to provide registration rights with respect to the shares issuable upon exercise of the Warrants and upon conversion under the Omnibus Agreement;"

        (b)  The definition of Registrable Securities in Section 1(d) of the Agreement is amended by deleting such Section 1(d) entirely and replacing it with the following:

        "(d) "Registrable Securities" means (i) the Common Stock of the Company issued upon exercise of the Warrants or issuable in connection with the future exercise of the Warrants; (ii) the Common Stock of the Company issued in connection with the Omnibus Agreement; and (iii) any Common Stock of the Company issued as (or issuable upon the conversion or exercise of any warrant, right or other security which is issued as) a dividend or other distribution with respect to, or in exchange for or in replacement of, such Warrants or Common Stock, excluding in all cases, however, any Registrable Securities sold by a person in a transaction in which its rights under this Agreement are not assigned;"

        (c)  Section 2(a) of the Agreement is amended by deleting such Section 2(a) entirely and replacing it with the following:

        "(a) If the Company shall receive a written request from the Holders of at least 25% of the Registrable Securities then outstanding (the "Initiating Holders") that the Company file a registration statement under the Act covering the registration of at least 25% of the Registrable Securities, then the Company shall (i) within 10 days after the receipt of such request, give written

Exh. 3-3

notice of such request to all Holders; (ii) subject to the limitations set forth below, file with the SEC a registration statement within 60 days after the receipt of such request, which registration statement shall cover all Registrable Securities that the Holders request to be registered within 30 days of receipt of the Company's notice; and (iii) use its best efforts to cause such registration statement to be declared effective on or prior to 120 days following the registration request."

        (d)  Section 2(b) of the Agreement is amended by deleting such Section 2(b) entirely and replacing it with the following:

        "(b) The Company is obligated to effect only three registrations pursuant to this Section 2."

        (e)  Section 4(a) of the Agreement is amended by deleting such Section 4 entirely and replacing it with the following:

        "(a) If the Company shall receive a written request from the Holders of at least 25% of the Registrable Securities then outstanding that the Company effect a registration on Form S-3 and the reasonably anticipated aggregate offering price to the public would equal or exceed $2,000,000, then the Company shall (i) within 10 days after the receipt of such request, give written notice of such request to all Holders; (ii) subject to the limitations set forth below, file with the SEC a Form S-3 within 60 days after the receipt of such request, which Form S-3 shall cover all Registrable Securities that the Holders request to be registered within 30 days of receipt of the Company's notice; and (iii) use its best efforts to cause such Form S-3 to be declared effective on or prior to 120 days following the registration request."

        (f)    Section 5(a) of the Agreement is amended by deleting such Section 5(a) entirely and replacing it with the following:

        "(a) Prepare and file with the SEC a registration statement with respect to such Registrable Securities and use its commercially reasonable efforts to cause such registration statement to be declared effective and, upon the request of the Holders of 25% of the Registrable Securities registered thereunder, keep such registration statement continuously effective until the earlier of one year or until the first date when all Registrable Securities covered by a registration statement shall have been sold or otherwise disposed of by the Holders whether pursuant to a registration statement or otherwise;"

        (g)  Section 8(a) of the Agreement is amended by deleting such Section 8(a) entirely and replacing it with the following:

        "(a) The Holders requesting registration under Section 2 must distribute the Registrable Securities covered by their request by means of a public offering. Simultaneously with making the request for registration under Section 2(a), the Initiating Holders shall provide the Company with the names of one or more reputable national or regional underwriters who have indicated a willingness to underwrite the offering, and the Company shall use its best efforts to enter into an underwriting agreement in customary form and reasonably acceptable to the Holders with one or more of such underwriters. Any failure of the Initiating Holders to provide underwriter information to the Company, or any failure by such underwriter(s) to proceed with the offering on customary terms, shall relieve the Company of its obligation to file such registration statement within 60 days after receipt of the registration request, though the Company shall still be obligated to use its reasonable best efforts to effect the registration as soon as practicable using such alternative underwriters as shall be identified by the Initiating Holders and reasonably acceptable to the Company. The right of any Holder to include its Registrable Securities in such registration under Section 2 shall be conditioned upon such Holder's participation in such underwriting and the inclusion of such Holder's Registrable Securities in the underwriting to the extent provided herein. All Holders proposing to distribute their Registrable Securities through such underwriting shall (together with the Company as provided in Section 5(e)) enter into an underwriting

Exh. 3-4

agreement in customary form with the underwriter or underwriters selected for such underwriting by a majority in interest of the Initiating Holders. Notwithstanding any other provision of Section 2, if the underwriter advises the Initiating Holders in writing that marketing factors require a limitation of the number of shares to be underwritten, then the Initiating Holders shall so advise all Holders of Registrable Securities which would otherwise have been underwritten pursuant to Section 2, and the number of shares of Registrable Securities that may be included in the registration shall be apportioned first pro rata among the selling Holders, including the Initiating Holders, according to the total amount of Registrable Securities requested to be sold in such registration by such Holders, then to the Company and then pro rata among any other selling stockholders according to the total amount of securities otherwise entitled to be included therein owned by each such selling stockholder, or in such other proportions as shall mutually be agreed to by such selling stockholders."

        (h)  Schedule A to the Agreement is amended by deleting such Schedule A entirely and replacing it with Schedule A to this Amendment.

        2.    No Other Changes.    Except as explicitly amended by this Amendment, the terms, conditions, rights and obligations under the Agreement shall remain in full force and effect.

        3.    Counterparts.    This Amendment may be executed by the parties hereto in any number of counterparts, each of which shall be deemed an original, but all of which shall constitute one and the same agreement.

Exh. 3-5

        IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of the date set forth above.

BRIGHAM EXPLORATION COMPANY

By:	/s/ DAVID T. BRIGHAM
Name:	David T. Brigham
Title:	Executive Vice President Land and Administration

Address:
Brigham Exploration Company
6300 Bridge Point Parkway
Building 2, Suite 500
Austin, TX 78730
Attention: Chief Financial Officer
Fax: 512-427-3400

DLJ MB FUNDING III, INC.

By: /s/ ROBERT CABES ROBERT CABES
Attorney-in-Fact

DLJ ESC II, LP

By:	DLJ LBO PLANS MANAGEMENT CORPORATION, its general partner
	By:	/s/ ROBERT CABES ROBERT CABES Attorney-in-Fact

DLJ MERCHANT BANKING PARTNERS III, L.P.

By:	DLJ MERCHANT BANKING III, INC., its Managing General Partner
	By:	/s/ ROBERT CABES ROBERT CABES Attorney-in-Fact

Exh. 3-6

DLJ MERCHANT BANKING III, INC., AS ADVISORY
GENERAL PARTNER ON BEHALF OF
DLJ OFFSHORE PARTNERS III, C.V.

By: /s/ ROBERT CABES ROBERT CABES
Attorney-in-Fact

DLJ MERCHANT BANKING III, INC.,
AS ADVISORY GENERAL PARTNER ON BEHALF OF
DLJ OFFSHORE PARTNERS III-1, C.V. AND AS
ATTORNEY-IN-FACT FOR DLJ MERCHANT BANKING III, L.P.,
AS ASSOCIATE GENERAL PARTNER OF
DLJ OFFSHORE PARTNERS III-1, C.V.

By: /s/ ROBERT CABES ROBERT CABES
Attorney-in-Fact

DLJ MERCHANT BANKING III, INC., AS ADVISORY
GENERAL PARTNER ON BEHALF OF
DLJ OFFSHORE PARTNERS III-2, C.V. AND
AS ATTORNEY-IN-FACT FOR DLJ MERCHANT BANKING III, L.P.,
AS ASSOCIATE GENERAL PARTNER OF
DLJ OFFSHORE PARTNERS III-2, C.V.

By: /s/ ROBERT CABES ROBERT CABES
Attorney-in-Fact

DLJ MB PARTNERSIII GmbH & CO. KG

By:	DLJ MERCHANT BANKING III, L.P., its Managing Limited Partner
	By:	DLJ MERCHANT BANKING III, INC., its General Partner
		By:	/s/ ROBERT CABES ROBERT CABES Attorney-in-Fact

Exh. 3-7

MILLENNIUM PARTNERS II, L.P.

By:	DLJ MERCHANT BANKING III, INC., its Managing General Partner
	By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact

MBP III PLAN INVESTORS, L.P.

By:	DLJ LBO PLANS MANAGEMENT CORPORATION, its Managing General Partner
	By:	/s/ ROBERT CABES ROBERT CABES Attorney-in-Fact

ADDRESSES FOR NOTICES TO CSFB ENTITIES:

Global Energy Partners
1100 Louisiana Street
Houston, Texas 77002
Fax: 713-890-1429
Attn: Steven A. Webster

and

CSFB Private Equity
11 Madison Avenue
New York, New York 10010
Fax: 212-448-3502
Attn: Dorian S. Forshner

Exh. 3-8

Schedule A
to Registration Rights Agreement

	Number of Shares
Holder Name	November 1, 2000	March 5, 2001	December 20, 2002
DLJ Merchant Banking Partners III, L.P.	4,681,393	1,478,337	1,848,463 1,657,241	* **
DLJ MB Funding III, Inc	125,748	39,709	- -0-
DLJ ESC II, LP	1,409,326	445,048	- -0-
DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III, C.V.	255,680	80,741	100,675 90,262	* **
DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-1, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-1, C.V.	85,360	26,956	33,699 30,211	* **
DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-2, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-2, C.V.	60,807	19,200	24,005 21,522	* **
DLJ MB PartnersIII GmbH & Co. KG	40,340	12,741	15,926 14,280	* **
Millennium Partners II, L.P.	8,013	2,531	3,210 2,878	* **
MBP III Plan Investors, L.P.	- -0-	- -0-	538,124 482,456	* **
Total	6,666,667	2,105,263	2,564,102 2,298,850	* **

*

Shares of Common Stock acquired pursuant to Omnibus Agreement

**

Shares of Common Stock issuable upon exercise of December 2002 Warrant Certificates

Exh. 3-9

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EXHIBIT 3

SECOND AMENDMENT TO REGISTRATION RIGHTS AGREEMENT
RECITALS
Schedule A to Registration Rights Agreement

EX-4

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EXHIBIT 4

OMNIBUS AGREEMENT

        This Omnibus Agreement (this "Agreement"), dated as of December 20, 2002, is by and among Brigham Exploration Company, a Delaware corporation (the "Company"), Brigham Oil & Gas, L.P., a Delaware limited partnership (the "Borrower"), and the Credit Suisse First Boston entities listed on Schedule A hereto (the "CSFB Entities"). Unless otherwise defined herein, all terms used herein shall have the meaning given such terms in the Credit Agreement (defined herein).

RECITALS

        WHEREAS, the CSFB Entities and Shell Capital Inc., a Delaware corporation ("SCI") are parties to that certain Assignment Agreement, dated as of November 21, 2002 (the "Assignment Agreement"), pursuant to which the CSFB Entities purchased the Assigned Interest (as such term is defined in the Assignment Agreement) (the "Assignment") held by SCI pursuant to that certain Amended and Restated Credit Agreement, dated as of February 17, 2000, among the Borrower, Agent, and each of the Lenders (as amended and supplemented, the "Credit Agreement");

        WHEREAS, the parties desire that the CSFB Entities immediately convert all outstanding Loans acquired by the CSFB Entities pursuant to the Assignment Agreement into 2,564,102 shares of the Company's common stock, $0.01 par value (the "Shares"), in accordance with the Equity Conversion Agreement (the "Conversion");

        WHEREAS, the parties desire to waive certain actions required under the Credit Agreement or other Loan Documents in order to effect the Conversion in an expedient manner; and

        WHEREAS, the Company, the Borrower and SCI are parties to that certain Exchange Agreement, dated as of November 21, 2002 (the "Exchange Agreement"), pursuant to which certain of the Loan Documents will be amended or terminated;

        NOW, THEREFORE, in consideration of the mutual representations, covenants, and agreements contained herein, the parties hereto, intending to be legally bound, hereby agree as follows:

        1.    No Liability; Release.    The Company and the Borrower agree that, upon completion of the Assignment and the Conversion, the CSFB Entities will not be a party to the Credit Agreement or any of the Loan Documents, and effective as of such time, the Company and the Borrower hereby release and indemnify the CSFB Entities from any liability of any kind thereunder (whether for matters occurring before or after the Conversion). The CSFB Entities acknowledge and agree that, upon completion of the Assignment and Conversion, they will have no further rights or obligations under the Credit Agreement or any of the Loan Documents and will cease to be a party under the Loan Documents.

        2.    Waiver of Delivery of Notes to the CSFB Entities.    The CSFB Entities hereby irrevocably waive the requirement under Section 12.06(d) of the Credit Agreement that the Borrower deliver new Notes representing the principal amount of the CSFB Entities' Maximum Credit Amount following the Assignment.

        3.    Conversion; Delivery of Stock Certificates.    On the Closing Date (as defined in the Assignment Agreement), the Company shall deliver stock certificates representing the Shares to the CSFB Entities in accordance with the allocations set forth in Schedule A hereto. The CSFB Entities shall not be required to present a Note representing the outstanding Loans owned in order to effect the Conversion.

Exh. 4-1

        4.    Waiver of Conversion Notice.    The Company and the Borrower hereby irrevocably waive any requirement under the Equity Conversion Agreement, including but not limited to Section 2.01(h) thereof, to provide any notice of the Conversion.

        5.    Inducement Payment.    The Company shall pay the CSFB Entities the sum of Five Hundred Thousand Dollars ($500,000) on the Closing Date as an inducement by the Company to the CSFB Entities to exercise their conversion rights under the Equity Conversion Agreement. In addition, the Company shall pay or reimburse all reasonable out-of-pocket expenses incurred by the CSFB Entities, including attorneys' fees, in connection with the transactions contemplated by the Assignment Agreement or this Agreement.

        6.    Conditions Precedent.    The effectiveness of this Agreement is subject to the execution and delivery of a consent and waiver letter executed by the Company, the Borrower, Agent and each of the Lenders in the form attached hereto as Exhibit A.

        7.    Notices.    All notices and other communications provided for herein (including, without limitation, any modifications of, or waivers, requests or consents under, this Agreement) shall be given or made in writing (including, without limitation, by telex or telecopy) to the intended recipient at its "Address for Notices" specified below its name on the signature pages hereof or, as to either party, at such other address as shall be designated by such party in a notice to the other party.

        8.    Amendment, Modification or Waiver.    No provision of this Agreement may be amended, modified or waived except by an instrument in writing signed by the parties.

        9.    Successors and Assigns.    This Agreement shall be binding upon and inure to the benefit of the parties hereto and their respective successors and assigns.

        10.    Governing Law.    This Agreement shall be, in accordance with New York General Obligations Law Section 5-1401, governed by and construed in accordance with the laws of the State of New York.

        11.    Headings.    The section headings appearing herein are included solely for convenience of reference and are not intended to affect the interpretation of any provision of this Agreement.

        12.    Counterparts.    This Agreement may be executed in any number of counterparts, each of which shall be identical and all of which, taken together, shall constitute one and the same instrument, and each of the parties hereto may execute this Agreement by signing any such counterpart.

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK.]

Exh. 4-2

        IN WITNESS WHEREOF, the parties hereto have executed this Agreement, or caused this Agreement to be executed by their respective duly authorized officers, as of the day and year first above written.

BRIGHAM EXPLORATION COMPANY
By:	/s/  DAVID T. BRIGHAM
Name:	David T. Brigham
Title:	Executive Vice President Land & Administration
Address for Notice:
6300 Bridge Point Parkway Building 2, Suite 500 Austin, TX 78730
BRIGHAM OIL & GAS, L.P.
	By:	Brigham, Inc.     Its General Partner
		By:	/s/  DAVID T. BRIGHAM
		Name:	David T. Brigham
		Title:	Executive Vice President
Address for Notice:
6300 Bridge Point Parkway Building 2, Suite 500 Austin, TX 78730
CSFB ENTITIES:
DLJ MERCHANT BANKING PARTNERS III, L.P.
By:	DLJ MERCHANT BANKING III, INC., its Managing General Partner
	By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact

Exh. 4-3

DLJ MERCHANT BANKING III, INC., AS ADVISORY GENERAL PARTNER ON BEHALF OF DLJ OFFSHORE PARTNERS III, C.V.
	By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact
DLJ MERCHANT BANKING III, INC., AS ADVISORY GENERAL PARTNER ON BEHALF OF DLJ OFFSHORE PARTNERS III-1, C.V. AND AS ATTORNEY-IN-FACT FOR DLJ MERCHANT BANKING III, L.P., AS ASSOCIATE GENERAL PARTNER OF DLJ OFFSHORE PARTNERS III-1, C.V.
	By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact
DLJ MERCHANT BANKING III, INC., AS ADVISORY GENERAL PARTNER ON BEHALF OF DLJ OFFSHORE PARTNERS III-2, C.V. AND AS ATTORNEY-IN-FACT FOR DLJ MERCHANT BANKING III, L.P., AS ASSOCIATE GENERAL PARTNER OF DLJ OFFSHORE PARTNERS III-2, C.V.
	By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact
DLJ MB PARTNERSIII GmbH & CO. KG
By:	DLJ MERCHANT BANKING III, L.P., its Managing Limited Partner
	By:	DLJ MERCHANT BANKING III, INC., its General Partner
		By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact

Exh. 4-4

MILLENNIUM PARTNERS II, L.P.
By:	DLJ MERCHANT BANKING III, INC., its Managing General Partner
	By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact
MBP III PLAN INVESTORS, L.P.
By:	DLJ LBO PLANS MANAGEMENT CORPORATION, its Managing General Partner
	By:	/s/  ROBERT CABES ROBERT CABES Attorney-in-Fact
ADDRESSES FOR NOTICES TO THE CSFB ENTITIES:
Global Energy Partners 1100 Louisiana Street Houston, Texas 77002 Fax: 713-890-1429 Attn: Steven A. Webster
and
CSFB Private Equity 11 Madison Avenue New York, New York 10010 Fax: 212-448-3502 Attn: Dorian S. Forshner

Exh. 4-5

SCHEDULE A

Holder Name	No. of Shares
DLJ Merchant Banking Partners III, L.P.	1,848,463
DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III, C.V.	100,675
DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-1, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-1, C.V.	33,699
DLJ Merchant Banking III, Inc., as Advisory General Partner on behalf of DLJ Offshore Partners III-2, C.V. and as attorney-in-fact for DLJ Merchant Banking III, L.P., as Associate General Partner of DLJ Offshore Partners III-2, C.V.	24,005
DLJ MB PartnersIII GmbH & Co. KG	15,926
Millennium Partners II, L.P.	3,210
MBP III Plan Investors, L.P.	538,124

Exh. 4-6

EXHIBIT A

        [Brigham Exploration Company Letterhead]

Bank of Montreal
700 Louisiana Street, Suite 4400
Houston, Texas 77002

Societe Generale
1111 Bagby Street, Suite 2020
Houston, Texas 77002

Shell Capital Inc.
910 Louisiana Street, Suite 5000
Houston, Texas 77002

The Royal Bank of Scotland plc
600 Travis Street, Suite 6070
Houston, Texas 77002

Re:        Consent and Waiver Request

Gentlemen and Ladies:

        Reference is made to (a) the Amended and Restated Credit Agreement dated as of February 17, 2000 (as amended to date, the "Senior Credit Agreement") among Brigham Oil & Gas, L.P., as Borrower ("Borrower"), Bank of Montreal, as Agent (in such capacity, "Senior Agent", and individually, "BMO"), and BMO, Societe Generale ("Soc Gen"), and Shell Capital Inc. ("SCI"), as Lenders, and (b) the Subordinated Credit Agreement dated as of October 31, 2000 (as amended to date, the "Subordinated Credit Agreement") as originally between Borrower and SCI and now among Borrower, the Royal Bank of Scotland plc, as Agent (as successor to SCI), and the Lenders signatory thereto.

        As used in this consent and waiver letter, "Loan Documents" means the "Loan Documents" as defined in either the Senior Credit Agreement or the Subordinated Credit Agreement, and "Brigham" means Brigham Exploration Company.

        Brigham and Borrower intend to participate in the transactions or enter into the agreements (a copy of each of which is attached hereto) described below:

        1.    a certain Assignment Agreement dated as of November 21, 2002 (the "Assignment Agreement") between SCI, DLJ Merchant Banking Partners III, L.P. and various other affiliates of, or entities otherwise associated with, Credit Suisse First Boston (collectively, "CSFB") pursuant to which, among other things, SCI will assign to CSFB the principal amount of the loans outstanding under the Senior Credit Agreement equal to $10,000,000 and the right to convert such loans into common stock of Brigham pursuant to the Equity Conversion Agreement dated as of February 17, 2000 (as amended to date, the "Equity Conversion Agreement") among SCI, Brigham and Borrower;

        2.    a certain Omnibus Agreement by and among Brigham, the Borrower and CSFB in the form attached to the Assignment Agreement, that provides, among other things, for the exercise by CSFB of its conversion right (the "Note Conversion") in accordance with the Equity Conversion Agreement, the payment of $500,000 by Brigham to CSFB as an inducement to the Note Conversion, and the consequent issuance of 2,564,102 shares of Brigham's common stock to CSFB;

        3.    a certain Exchange Agreement dated as of November 21, 2002 (the "Exchange Agreement") by and between Brigham, the Borrower and SCI, pursuant to which, among other things, Brigham will issue 550,000 shares of its common stock to SCI, SCI will surrender all of its

Exh. 4-7

warrants issued by Brigham, and Brigham, the Borrower and SCI will terminate the Equity Conversion Agreement and other documents described therein;

        4.    a certain Registration Rights Agreement between Brigham and SCI in the form attached to the Exchange Agreement, pursuant to which SCI and its successors and assigns will have "demand" and "piggy back" registration rights to obtain registration of such 550,000 shares of common stock in certain circumstances; and

        5.    the sale by Brigham to CSFB, for $10,000,000 in cash, of shares of a new, mandatorily redeemable preferred stock plus new warrants to purchase common stock of Brigham at $4.35 per share, as more fully described on Exhibit A.

        As a result of these transactions, both the "Maximum Credit Amount" of SCI under the Senior Credit Agreement and the principal balance of SCI's loans under the Senior Credit Agreement will be reduced to $30,000,000, and, after giving effect to the Note Conversion, CSFB will have no such "Maximum Credit Amount".

        Please execute a copy of this consent and waiver letter in the space provided below to evidence (a) your consent to the execution of the documents described above and the consummation of the transactions therein and herein on the terms described above, (b) your agreement that the Assignment Agreement and the Note Conversion may be completed without any issuance of a new $10,000,000 promissory note to CSFB and without any surrender of such a note by CFSB to Brigham or Borrower, (c) your agreement that, upon completion of the Assignment Agreement and the Note Conversion, CSFB will not be a party to the Senior Credit Agreement or any of the Loan Documents and your release of CSFB from any liability of any kind thereunder (whether for matters occurring before or after the Note Conversion), and (d) your agreement to confirm the foregoing in writing directly to CSFB, if hereafter requested to do so.

        Brigham and Borrower hereby (x) waive any requirement in the Loan Documents that the Senior Agent or SCI give either of them notice of any of the transactions described above (whether under Section 12.06(d) of the Senior Credit Agreement, under the Equity Conversion Agreement, or otherwise), (y) agree to issue a new promissory note to SCI, in the stated amount of $30,000,000, and (z) confirm to Senior Agent, BMO, Soc Gen and SCI that the Loan Documents remain in full force and effect and (except as described in the Exchange Agreement) will remain in full force and effect after giving effect to the transactions described above.

        This consent and waiver letter shall be governed by and construed under the laws of the State of Texas. This consent and waiver letter may be executed in multiple counterparts, and by the different parties hereto in separate counterparts (which may be delivered, among other ways, by the exchange of faxed signature pages), and all of such counterparts will constitute a single letter agreement.

Exh. 4-8

        Thank you very much for your cooperation.

Yours truly,
BRIGHAM EXPLORATION COMPANY
	By:	Name: Title:
BRIGHAM OIL & GAS, L.P.
By:	Brigham, Inc., its general partner
	By:	Name: Title:

CONSENTED TO as of the date set out above:

BANK OF MONTREAL, as Senior Agent and Lender
By:
	Name:
	Title:
SOCIETE GENERALE
By:
	Name:
	Title:
SHELL CAPITAL INC.
By:
	Name:
	Title:
THE ROYAL BANK OF SCOTLAND plc
By:
	Name:	Peter Buchanan
	Title:	Director

Exh. 4-9

EXHIBIT A

[Description of preferred stock and warrants to come based on final term sheet.]

Exh. 4-10

QuickLinks

EXHIBIT 4

OMNIBUS AGREEMENT
RECITALS
SCHEDULE A
EXHIBIT A
EXHIBIT A