REGISTRATION RIGHTS AGREEMENT

the Holders requesting registration a resolution of the Board that, in the good faith judgment of the Board, such registration and offering would reasonably be expected to materially adversely affect any bona fide material financing of the Company or any material transaction under consideration by the Company or would require disclosure of information that has not been disclosed to the public and is not otherwise required to be disclosed at that time, the premature disclosure of which would materially adversely affect the Company.  Such Board resolution shall contain a statement of the reasons for such postponement and an approximation of the anticipated delay.  The Holders receiving such resolution shall keep the information contained in such resolution confidential on the same terms set forth in Section 5(p).  If the Company shall so postpone the filing of a Registration Statement, the Holder who made the Demand Registration shall have the right to withdraw the request for registration by giving written notice to the Company within twenty (20) days of the anticipated termination date of the postponement period, as provided in such resolution delivered to the Holders, and in the event of such withdrawal, such request shall not be counted for purposes of the number of Demand Registrations to which such Holder is entitled pursuant to the terms herein.

(d)           Use, and Suspension of Use, of Shelf Registration.  If the Company has filed a Registration Statement for a Shelf Registration, the Company shall be entitled to suspend (but not more than an aggregate of ninety (90) days in any twelve month period), for a reasonable period of time not in excess of ninety (90) days, the offer or sale of Registrable Securities pursuant to such Registration Statement if (i) a “road show” is not then in progress with respect to a proposed offering of Registrable Securities pursuant to such Registration Statement and no Holder has executed an underwriting agreement with respect to a pending sale of Registrable Securities pursuant to such Registration Statement and (ii) the Company delivers to the Holders of Registrable Securities included in such Registration Statement a resolution of the Board that, in the good faith judgment of the Board, such offer or sale would reasonably be expected to materially adversely affect any bona fide material financing of the Company or any material transaction under consideration by the Company or would require disclosure of information that has not been disclosed to the public and is not otherwise required to be disclosed at that time, the premature disclosure of which would materially adversely affect the Company.  Such Board resolution shall contain a statement of the reasons for such postponement and an approximation of the anticipated delay.  The Holders receiving such resolution shall keep the information contained in such certificate confidential on the same terms set forth in Section 5(p).

Section 3.              Piggyback Registration.

(a)           Right to Piggyback.  If, at any time after an IPO, the Company proposes to file a registration statement under the Securities Act with respect to an offering of Common Stock (other than a registration statement (i) on Form S-4, Form S-8 or any successor forms thereto, (ii) filed solely in connection with an exchange offer or any employee benefit or dividend reinvestment plan or (iii) filed for a Demand Registration that is not a Shelf Registration), then, each such time, the Company shall give prompt written notice of such proposed filing at least fifteen (15) days before the anticipated filing date (the “Piggyback Notice”) to all Holders.  The Piggyback Notice shall offer Holders the opportunity to include in such registration statement the number of Registrable Securities as each such Holder may request (a “Piggyback Registration”).  Subject to Section 3(b) hereof, the Company shall include in each such Piggyback Registration all Registrable Securities with respect to which the Company has received written requests for

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inclusion therein within ten (10) days after notice has been given to the Holders.  Holders exercising their rights under this Section 3(a) shall be permitted to withdraw all or part of the Registrable Securities from a Piggyback Registration at any time prior to the effective date of such Piggyback Registration.  The Company shall not be required to maintain the effectiveness of the Registration Statement for a Piggyback Registration beyond the earlier to occur of (i) one hundred eighty (180) days after the effective date thereof and (ii) consummation of the distribution of the Registrable Securities included in such Registration Statement.  Notwithstanding the foregoing, any Holder participating in a Shelf Registration may request that such Holder’s Registrable Securities be removed from such Registration Statement after effectiveness, in which event the Company shall promptly either withdraw such Registration Statement or file a post-effective amendment to such Registration Statement removing such Registrable Securities.

(b)           Priority on Piggyback Registrations.  The Company shall use its reasonable best efforts to cause the managing underwriter or underwriters of a proposed underwritten offering to include all Registrable Securities requested by Holders under this Section on the same terms and conditions as any other shares of Common Stock of the Company included therein.  Notwithstanding the foregoing, if the managing underwriter or underwriters of such underwritten offering have informed the Company in writing that in its or their view the total number of shares or dollar amount of Common Stock that the Holders, the Company and any other Persons having rights to participate in such registration, intend to include in such offering is such as to adversely affect the success of such offering, then the number of shares of Common Stock that in the opinion of such managing underwriter can be sold without adversely affecting such offering shall be included in the following order:

First, the shares of Common Stock being offered for the account of the Company;

Second, the Investor Securities, pro rata based on the number of Investor Securities requested to be included by Holders thereof;

Third, the Management Securities, pro rata based on the number of Management Securities requested to be included by the Holders thereof; and

Fourth, the shares of Common Stock being offered for the account of any other Persons, pro rata based on the number of shares of Common Stock requested to be included by the holders thereof.

Notwithstanding anything contained herein to the contrary, the Company hereby agrees that (i) any Piggyback Registration that is a Shelf Registration shall contain all language (including, without limitation, on the Prospectus cover sheet, the principal stockholders’ table and the plan of distribution) as may be reasonably requested by a Holder to allow for a Partner Distribution and (ii) the Company shall, at the reasonable request of any Holder seeking to effect a Partner Distribution, file any Prospectus supplement or post-effective amendments and otherwise take any action reasonably necessary to include such language, if such language was not included in the initial Registration Statement, or revise such language if deemed reasonably necessary by such Holder to effect such Partner Distribution.

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Notwithstanding anything herein to the contrary, in respect of any offering contemplated herein (whether under Section 2, Section 3 or otherwise) no Holder or any of its affiliates (other than the Company), officers, directors, partners, members, stockholders or representatives shall be required, directly or indirectly, to make any representations or warranties to, or agreements with, the Company or the underwriters (including, without limitation, agreements with respect to indemnification) other than representations, warranties or agreements regarding such Holder, its ownership of and title to the Registrable Securities and its intended method of distribution, and any liability of any such Holder or its affiliates (other than the Company) to any underwriter or other Person under such underwriting agreement shall be limited to liability arising from breach of its representations and warranties and shall be limited to an amount equal to the total price at which the Registrable Securities sold by such Holder were offered to the public (net of discounts and commissions paid by such Holder in connection with such offering).

Section 4.              Restrictions on Public Sale by Holders.

Each Holder agrees, in connection with any underwritten offering made pursuant to a Registration Statement (whether or not such Holder elected to include Registrable Securities in such Registration Statement), if requested (pursuant to a written notice) by the managing underwriter or underwriters in an underwritten offering, not to effect any public sale or distribution of any Common Stock (except as part of such underwritten offering), including a sale pursuant to Rule 144, or to give any Demand Notice, in each case during the period commencing on the date of the request (which shall be no earlier than 14 days prior to the expected “pricing” of such offering) and continuing for not more than (a) ninety (90) days with respect to any underwritten public offering made prior to the second anniversary of the IPO or (b) sixty (60) days with respect to any underwritten public offering made after the second anniversary of the IPO, after the date of the Prospectus (or Prospectus supplement if the offering is a Shelf Registration) pursuant to which such public offering shall be made or such shorter period as is required by the managing underwriter, provided, however, that the Company and all officers, directors and managers, as applicable, of the Company must be subject to the same restrictions.

Section 5.              Registration Procedures.

If and whenever the Company is required to register the offer and sale under the Securities Act of any Registrable Securities pursuant to the terms of this Agreement, the Company shall take all such actions as are reasonably necessary to cause such registration to be effected as expeditiously as possible, including the following:

Prepare and file with the SEC a Registration Statement or Registration Statements on any form which shall be available for the offer and sale of the Registrable Securities by the Holders in accordance with the intended method or methods of distribution of such Registrable Securities (including, without limitation, a Partner Distribution), and use its reasonable best efforts to cause such Registration Statement to become effective and to remain effective as provided herein; provided, however, that no later than ten (10) days before filing a Registration Statement or Prospectus or any amendments or supplements thereto (including, without limitation, documents that would be incorporated or deemed to be incorporated therein by reference), the Company shall furnish or otherwise make available to the Holders of the Registrable Securities covered by

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such Registration Statement, their counsel and the managing underwriters, if any, copies of all such documents proposed to be filed, which documents shall be subject to the review and comments of such Holders, counsel and managing underwriters.  The Company shall not file any such Registration Statement or Prospectus or any amendments or supplements thereto (including, without limitation, such documents that, upon filing, would be incorporated or deemed to be incorporated by reference therein) with respect to a Demand Registration to which the Holders of 66 2/3% of the Registrable Securities covered by such Registration Statement, their counsel, or the managing underwriters, if any, shall reasonably object, unless, in the opinion of the Company and its counsel, such filing is necessary to comply with applicable law.

Prepare and file with the SEC such amendments and post-effective amendments to each Registration Statement as may be necessary to keep such Registration Statement continuously effective during the period provided herein and comply in all material respects with the provisions of the Securities Act with respect to the disposition of all securities covered by such Registration Statement; and cause the related Prospectus to be supplemented by any Prospectus supplement as may be necessary to comply with the provisions of the Securities Act with respect to the disposition of the securities covered by such Registration Statement, and as so supplemented to be filed pursuant to Rule 424 (or any similar provisions then in force) under the Securities Act; provided, however, that any Holder of Registrable Securities that has been included in a Registration Statement for a Shelf Registration may request that such Holder’s Registrable Securities be removed from such Registration Statement, in which event the Company shall promptly either withdraw such Registration Statement or file a post-effective amendment to such Registration Statement removing such Registrable Securities.

Notify each Holder of Registrable Securities included in a Registration Statement, its counsel and the managing underwriters, if any, promptly, and (if requested by any such Person) confirm such notice in writing, (i) when a Prospectus or any Prospectus supplement or post-effective amendment related to such Registration Statements has been filed, and, with respect to a Registration Statement or any post-effective amendment, when the same has become effective, (ii) of any notice from the SEC that there will be a review of such Registration Statement and promptly provide such Holders, their counsel and the managing underwriters, if any, with a copy of any SEC comments received by the Company in connection therewith, (iii) of any request by the SEC or any other Federal or state governmental authority for amendments or supplements to such Registration Statement or related Prospectus or for additional information, (iv) of the issuance by the SEC of any stop order suspending the effectiveness of such Registration Statement or the initiation of any proceedings for that purpose, (v) if at any time the representations and warranties of the Company contained in any applicable agreement (including, without limitation, any underwriting agreement) contemplated by Section 5(o) below cease to be true and correct, (vi) of the receipt by the Company of any notification with respect to the suspension of the qualification or exemption from qualification of any of such Registrable Securities for sale in any jurisdiction, or the initiation or threatening of any proceeding for such purpose, and (vii) of the occurrence of any event that makes any statement made in such Registration Statement or related Prospectus or any document incorporated or deemed to be incorporated therein by reference untrue in any material respect or that requires the making of any changes in such Registration Statement, Prospectus or documents so that, in the case of the Registration Statement, it will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein, in

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light of the circumstances under which they were made, not misleading, and that in the case of the Prospectus, it will not contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading.

Use its reasonable best efforts to obtain the withdrawal of any order suspending the effectiveness of a Registration Statement, or the lifting of any suspension of the qualification (or exemption from qualification) of any of the Registrable Securities for sale in any jurisdiction.

If requested by the managing underwriters, if any, or any Holder of Registrable Securities being sold in connection with an underwritten offering, promptly include in a Prospectus supplement or post-effective amendment such information as the managing underwriters, if any, and such Holders may reasonably request in order to permit the intended method of distribution of such Registrable Securities and make all required filings of such Prospectus supplement or such post-effective amendment as soon as practicable after the Company has received such request.

Furnish or make available to each Holder of Registrable Securities included in a Registration Statement, its counsel and each managing underwriter, if any, without charge, at least five (5) conformed copies of such Registration Statement, the Prospectus and Prospectus supplements, if applicable, and each post-effective amendment thereto, including financial statements (but excluding schedules, all documents incorporated or deemed to be incorporated therein by reference and all exhibits, unless requested by such holder, counsel or underwriter).

Deliver to each Holder of Registrable Securities included in a Registration Statement, its counsel and the underwriters, if any, without charge, as many copies of the  related Prospectus or Prospectuses (including each form of Prospectus) and each amendment or supplement thereto as such Persons may reasonably request in connection with the distribution of such Registrable Securities; and the Company, subject to the last paragraph of this Section 5, hereby consents to the use of such Prospectus and each amendment or supplement thereto by each of such Holders and the underwriters, if any, in connection with the offer and sale of such Registrable Securities.

Prior to any public offering of Registrable Securities, use its reasonable best efforts to register or qualify or cooperate with the Holders of such Registrable Securities, the underwriters, if any, and their respective counsel in connection with the registration or qualification (or exemption from such registration or qualification) of such Registrable Securities for offer and sale under the securities or “Blue Sky” laws of such jurisdictions within the United States as any seller or underwriter reasonably requests and to keep each such registration or qualification (or exemption therefrom) effective during the period such Registration Statement is required to be kept effective and to take any other action that may be necessary or advisable to enable such Holders to consummate the disposition of such Registrable Securities in such jurisdiction; provided, however, that the Company will not be required to (i) qualify generally to do business in any jurisdiction where it is not then so qualified or (ii) take any action that would subject it to general service of process in any such jurisdiction where it is not then so subject.

Cooperate with the Holders of Registrable Securities included in a Registration Statement and the managing underwriters, if any, to facilitate the timely preparation and delivery of

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certificates (not bearing any legends) representing such Registrable Securities, after receiving written representations from each such Holder that the Registrable Securities represented by the certificates so delivered by such Holder will be transferred in accordance with such Registration Statement, and enable certificates representing such Registrable Securities to be in such denominations and registered in such names as the managing underwriters, if any, or Holders may request at least two (2) Business Days prior to any sale of such Registrable Securities in a firm commitment public offering, but in any other such sale, within ten (10) Business Days prior to having to deliver such certificates.

Use its reasonable best efforts to cause the Registrable Securities covered by a Registration Statement to be registered with or approved by such other governmental agencies or authorities within the United States, except as may be required solely as a consequence of the nature of the business of the Holder of such Registrable Securities, in which case the Company will cooperate in all reasonable respects with the filing of such registration and the granting of such approvals, as may be necessary to enable such Holders or the underwriters, if any, to consummate the disposition of such Registrable Securities.

Upon the occurrence of any event contemplated by Section 5(c)(vii) above, prepare a supplement or post-effective amendment to a Registration Statement or a supplement to the related Prospectus or any document incorporated or deemed to be incorporated therein by reference, or file any other required document so that, as thereafter delivered to the purchasers of the Registrable Securities being sold thereunder, such Prospectus will not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading.

Prior to the effective date of a Registration Statement, provide a CUSIP number for the Registrable Securities being offered and sold thereunder.

Provide and cause to be maintained a transfer agent and registrar for all Registrable Securities covered by a Registration Statement from and after a date not later than the effective date of such Registration Statement.

Use its reasonable best efforts to cause all Registrable Securities covered by a Registration Statement to be authorized to be quoted on the NASDAQ Global Market or listed on a national securities exchange if shares of the particular class of Registrable Securities are at that time quoted on the NASDAQ Global Market or listed on such exchange, as the case may be.

Enter into such agreements (including, without limitation, an underwriting agreement in form, scope and substance as is customary in underwritten offerings) and take all such other actions reasonably requested by the Holders of a majority of the Registrable Securities included in a Registration Statement (including those reasonably requested by the managing underwriters, if any) to expedite or facilitate the offer and sale of such Registrable Securities, and in such connection, whether or not an underwriting agreement is entered into and whether or not such Registration Statement includes an underwritten offering, (i) make such representations and warranties to the Holders of the Registrable Securities included in such Registration Statement and the underwriters, if any, in form, substance and scope as are customarily made by issuers to

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underwriters in underwritten offerings, and, if true, confirm the same if and when requested, (ii) furnish to such Holders opinions of counsel and a negative assurance letter to the Company and updates thereof (which counsel, opinions and letter (in form, scope and substance, in the case of such opinions and such letter) shall be reasonably satisfactory to such Holders, the managing underwriters, if any, and counsels to such Holders), addressed to each such Holder and each of the underwriters, if any, covering the matters customarily covered in opinions and negative assurance letters requested in underwritten offerings and such other matters as may be reasonably requested by such Holders, counsel and underwriters, (iii) obtain “cold comfort” letters and updates thereof from the independent certified public accountants of the Company (and, if necessary, any other independent certified public accountants of any subsidiary of the Company or of any business acquired by the Company for which financial statements and financial data are, or are required to be, included in the Registration Statement) who have certified the financial statements included in such Registration Statement, addressed to each such Holder (unless such accountants shall be prohibited from so addressing such letters by applicable standards of the accounting profession) and each of the underwriters, if any, such letters to be in customary form and covering matters of the type customarily covered in “cold comfort” letters in connection with underwritten offerings, which form and substance shall be reasonably acceptable to such Holders, (iv) obtain a report of the independent petroleum engineers of the Company relating to the oil and natural gas reserves of the Company, such report to be in customary form and covering matters customarily covered in such reports, (v) if an underwriting agreement is entered into, the same shall contain indemnification provisions and procedures substantially to the effect set forth in Section 7 hereof with respect to all parties to be indemnified pursuant to said Section and (vi) deliver such documents and certificates as may be reasonably requested by any such Holder, such Holder’s counsel and the managing underwriters, if any, to evidence the continued validity of the representations and warranties made pursuant to Section 5(o)(i) above and to evidence compliance with the conditions contained in the underwriting agreement or other agreement entered into by the Company.  The above shall be done at each closing under such underwriting or similar agreement, or as and to the extent required thereunder.

Make available for inspection by the Holders of Registrable Securities included in a Registration Statement, any underwriter participating in an offer and sale of such Registrable Securities, if any, and any attorneys or accountants retained by such Holders or underwriter, at the offices where normally kept, during reasonable business hours, all financial and other records, pertinent corporate documents and properties of the Company and its subsidiaries, and cause the officers, directors and employees of the Company and its subsidiaries to supply all information in each case reasonably requested by any such Holder, underwriter, attorney or accountant in connection with such Registration Statement; provided, however, that any information that is not publicly available at the time of delivery of such information shall be kept confidential by such Persons (other than disclosure by such Persons to such Persons’ respective affiliates) unless (i) disclosure of such information is required by court or administrative order or other legal process, (ii) disclosure of such information is required by law, or (iii) such information becomes generally available to the public other than as a result of a disclosure or failure to safeguard by such Person.  In the case of a proposed disclosure pursuant to (i) or (ii) above, such Person shall be required to give the Company written notice of the proposed disclosure prior to such disclosure and, if requested by the Company, assist the Company in seeking to prevent or limit the proposed disclosure.

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Comply with all applicable rules and regulations of the SEC and make available to the holders of the Common Stock earning statements satisfying the provisions of Section 11(a) of the Securities Act and Rule 158 thereunder, or any similar rule promulgated under the Securities Act, no later than forty-five (45) days after the end of any twelve (12) month period (or ninety (90) days after the end of any twelve (12) month period if such period is a fiscal year) (i) commencing at the end of any fiscal quarter in which Registrable Securities are sold to underwriters in a firm commitment or best efforts underwritten offering and (ii) if not sold to underwriters in such an offering, commencing on the first day of the first fiscal quarter of the Company after the effective date of a Registration Statement, which statements shall cover one of said twelve (12) month periods.

Cause its officers to support the marketing of the Registrable Securities covered by a Registration Statement (including, without limitation, participation in “road shows”).

Notwithstanding anything contained herein to the contrary, the Company hereby agrees that any Shelf Registration shall contain all language (including, without limitation, on the prospectus cover sheet, the principal stockholders’ table and the plan of distribution) as may be reasonably requested by a Holder of Registrable Securities included in such Shelf Registration.  The Company may require each such Holder to furnish to the Company in writing such information required in connection with such registration regarding such Holder and the distribution of such Registrable Securities as the Company may, from time to time, reasonably request in writing.

Each Holder agrees if such Holder has Registrable Securities included in a Registration Statement that, upon receipt of any notice from the Company of the occurrence of any event of the kind described in Section 5(c)(iii), 5(c)(iv), 5(c)(v), 5(c)(vi) or 5(c)(vii) hereof, such Holder will forthwith discontinue disposition of such Registrable Securities covered by such Registration Statement or Prospectus until such Holder is advised in writing by the Company that the disposition may be resumed and, if applicable, has received copies of the supplemented or amended Prospectus contemplated by Section 5(k) hereof, together with any additional or supplemental filings that are incorporated or deemed to be incorporated by reference in such Prospectus; provided, however, that the Company shall extend the time periods under Section 2 with respect to the length of time that the effectiveness of such Registration Statement must be maintained by the amount of time the holder is required to discontinue disposition of such securities.

Section 6.              Registration Expenses.

The Company shall pay all Registration Expenses in connection with the registration of the Registrable Securities pursuant to this Agreement regardless of whether or not any Registration Statement is filed or becomes effective.  In addition, the Company shall pay its internal expenses (including, without limitation, all salaries and expenses of its officers and employees performing legal or accounting duties), the expense of any annual audit, the fees and expenses incurred in connection with the listing of the securities to be registered on any securities exchange on which similar securities issued by the Company are then listed and rating agency fees and the fees and expenses of any Person, including special experts, retained by the Company.

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The Company shall not be required to pay (i) fees and disbursements of any counsel retained by any Holder of Registrable Securities or by any underwriter (except as set forth in clauses 6(i)(B) and 6(viii)), (ii) any underwriter’s fees (including discounts, commissions or fees of underwriters, selling brokers, dealer managers or similar securities industry professionals) relating to the distribution of Registrable Securities for the account of a Holder or (iii) any other expenses of a Holder not specifically required to be paid by the Company pursuant to the first paragraph of this Section 6.

Section 7.              Indemnification.

Indemnification by the Company.  The Company shall, without limitation as to time, indemnify and hold harmless, to the fullest extent permitted by law, each Holder whose Registrable Securities are covered by a Registration Statement or Prospectus, the affiliates, officers, directors, partners, members, managers, stockholders, accountants, attorneys, agents and employees of each of them, each Person who controls each such Holder (within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act) and the officers, directors, partners, members, managers, stockholders, accountants, attorneys, agents and employees of each such controlling person (collectively, the “Stockholder Indemnified Persons”), from and against any and all Losses, as incurred, arising out of or based upon (i) any untrue statement (or alleged untrue statement) of a material fact contained in any Prospectus, offering circular or other document (including, without limitation, any related Registration Statement, Issuer Free Writing Prospectus, or similar issuer information filed or required to be filed pursuant to Rule 433(d) under the Securities Act) incident to any such registration, qualification, or compliance, (ii) any omission (or alleged omission) to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading or, with respect to any prospectus, necessary to make the statements therein, in light of the circumstances under which they were made, not misleading, or (iii) any violation by the Company of the Securities Act or state securities or Blue Sky laws or, in each case, any rule or regulation thereunder applicable to the Company and relating to action or inaction required of the Company in connection with any such registration, qualification, or compliance, and will reimburse each such Stockholder Indemnified Person for any legal and any other expenses reasonably incurred in connection with investigating and defending or settling any Proceeding relating to any such Losses; provided, however, that the Company will not be liable in any such case to the extent that any such Losses arise out of or are based on any untrue statement or omission by such Holder or underwriter, but only to the extent, that such untrue statement (or alleged untrue statement) or omission (or alleged omission) is made in such Registration Statement, Prospectus, offering circular, or other document in reliance upon and in conformity with written information furnished to the Company by such Holder or underwriter specifically for use in connection with the preparation of such Registration Statement, Prospectus, offering circular or other document.  It is agreed that the indemnity agreement contained in this Section 7(a) shall not apply to amounts paid in settlement of any such Losses if such settlement is effected without the consent of the Company (which consent shall not be unreasonably withheld).  The Company also agrees to indemnify any underwriter of Registrable Securities and each Person who controls (within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act) such underwriter, on substantially the same basis as that provided to the Stockholder Indemnified Persons in this Section 7(a).