REGISTRATION RIGHTS AGREEMENT

Exhibit 10.8

REGISTRATION RIGHTS AGREEMENT

DATED AS OF AUGUST 11, 2005

BY AND BETWEEN

BRONCO DRILLING COMPANY, INC.

AND

BRONCO DRILLING HOLDINGS, L.L.C.

TABLE OF CONTENTS

REGISTRATION RIGHTS AGREEMENT

THIS REGISTRATION RIGHTS AGREEMENT (the “Agreement”) is made and entered into as of August 11, 2005, by and between Bronco Drilling Company, Inc., a Delaware corporation (the “Company”), and Bronco Drilling Holdings, L.L.C., a Delaware limited liability company (the “Stockholder”).

WHEREAS, the Company was formed in May 2005 as a wholly owned subsidiary of the Bronco Drilling Company, L.L.C., an Oklahoma limited liability company (“Bronco”) in contemplation of an initial public offering of common stock of the Company (“Common Stock Offering”);

WHEREAS, immediately prior to the commencement of the Common Stock Offering, on the date hereof the Company, Bronco and Stockholder will enter into a transaction (the “Merger”) in which (i) Bronco mergers with and into the Company with the Company being the surviving corporation of the Merger and (ii) Stockholder will receive 13,360,000 validly issued, fully paid and nonassessable shares of common stock, par value $0.01 per share, of the Company; and

WHEREAS, in connection with the Merger, the parties hereto desire to enter into this Agreement to govern certain of their rights, duties and obligations relating to registration of the Registrable Securities (as defined herein).

NOW, THEREFORE, for good, valuable and binding consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto, intending to be legally bound hereby, now agree as follows:

STATEMENT OF AGREEMENT

Section 1. Definitions.

As used in this Agreement, the following terms shall have the meanings set forth below:

“Charter” means the Amended and Restated Certificate of Incorporation of the Company, as amended from time to time.

“Commission” means the United States Securities and Exchange Commission or any other United States federal agency at the time administering the Securities Act.

“Common Stock” means the Company’s common stock, par value $0.01 per share, or any other shares of capital stock or other securities of the Company into which such shares of Common Stock shall be reclassified or changed, including by reason of a merger, consolidation, reorganization or recapitalization. If the Common Stock has been so reclassified or changed, or if the Company pays a dividend or makes a distribution on the Common Stock in shares of capital stock, or subdivides (or combines) its outstanding shares of Common Stock into a greater (or smaller) number of shares of Common Stock, a share of Common Stock shall be deemed to be

such number of shares of stock and amount of other securities to which a holder of a share of Common Stock outstanding immediately prior to such change, reclassification, exchange, dividend, distribution, subdivision or combination would be entitled.

“Delay Period” has the meaning set forth in Section 4(a) of this Agreement.

“Demand Notice” has the meaning set forth in Section 2(a) of this Agreement.

“Demand Registration” has the meaning set forth in Section 2(a) of this Agreement.

“Exchange Act” means the U.S. Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder.

“Holder” means a person who owns Registrable Securities and is either (i) the Stockholder or a Permitted Transferee of the Stockholder that has agreed to be bound by the terms of this Agreement as if such Person were the Stockholder, (ii) upon the death of any Holder, the executor of the estate of such Holder or such Holder’s heirs, devisees, legatees or assigns or (iii) upon the disability of any Holder, any guardian or conservator of such Holder.

“Interruption Period” has the meaning set forth in the last paragraph in Section 4(b).

“Losses” has the meaning set forth in Section 6(a) of this Agreement.

“Misstatement/Omission” has the meaning set forth in Section 6(a) of this Agreement.

“Permitted Transferee” means any Person to whom the rights under this Agreement have been assigned in accordance with the provisions of Section 10(d) hereof.

“Person” means any natural person, corporation, partnership, firm, association, trust, government, governmental agency, limited liability company or any other entity, whether acting in an individual, fiduciary or other capacity.

“Piggyback Registration” has the meaning set forth in Section 3(a) of this Agreement.

“Prospectus” means the prospectus included in any Registration Statement, as amended or supplemented by any prospectus supplement, with respect to the terms of the offering of any portion of the Registrable Securities covered by such Registration Statement, and all other amendments and supplements to the Prospectus, including post-effective amendments, and all material incorporated by reference or deemed to be incorporated by reference in such prospectus.

“Registrable Securities” means the shares of Common Stock issued to the Stockholder in connection with the Reorganization. If as a result of any reclassification, stock dividends or stock splits or in connection with a combination of shares, recapitalization, merger, consolidation or other reorganization or other transaction or event, any capital stock, evidence of indebtedness, warrants, options, rights or other securities (collectively “Other Securities”) are issued or transferred to a Holder in respect of Registrable Securities held by the Holder, references herein

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to Registrable Securities shall be deemed to include such Other Securities. As to any particular Registrable Securities, such securities will cease to be Registrable Securities when (i) they have been distributed to the public pursuant to an offering registered under the Securities Act, (ii) they have been distributed to the public pursuant to Rule 144 (or any successor provision) under the Securities Act, or (iii) they have been sold to any Person to whom the rights under this Agreement are not assigned in accordance with this Agreement.

“Registration Statement” means any registration statement under the Securities Act of the Company that covers any of the Registrable Securities, including the related Prospectus, amendments and supplements to such registration statement or Prospectus, including pre- and post-effective amendments, all exhibits, and all materials incorporated by reference or deemed to be incorporated by reference in such registration statement or Prospectus.

“Securities Act” means the United States Securities Act of 1933, as amended, and the rules and regulations of the Commission promulgated thereunder.

“Stockholder” has the meaning set forth in the introductory paragraph of this Agreement.

Section 2. Demand Registrations.

(a) Right to Demand. Upon the terms and subject to the conditions of this Agreement, (i) Holders of at least a majority of the aggregate amount of outstanding Registrable Securities shall have the right, by written notice (the “Demand Notice”) given to the Company, to request the Company to register under and in accordance with the provisions of the Securities Act all or part of the Registrable Securities designated by such Holders (a “Demand Registration”). Upon receipt of any such Demand Notice, the Company will promptly notify all other Holders of the receipt of such Demand Notice and allow them the opportunity to include Registrable Securities in the proposed registration by giving notice to the Company within five days after the Holder receives such notice; provided, that Holders joining in a proposed registration pursuant to this sentence shall not be deemed to have exercised a Demand Registration for purposes of Section 2(b) hereof and such Holders shall be included in such registration on the basis set forth in Section 2(h) hereof. The Company shall not be required to register any Registrable Securities under this Section 2 unless the anticipated aggregate offering price to the public for any such offering of the Registrable Securities included in such Demand Notice is expected to be at least $1 million.

(b) Number of Demand Registrations. Holders shall be entitled to have three Demand Registrations effected. A Demand Registration shall not be deemed to be effected and shall not count as a Demand Registration of any Person (i) if a Registration Statement with respect thereto shall not have become effective under the Securities Act and remained effective (A) for at least 180 days (excluding any Interruption Period or Delay Period) in the case of a Demand Registration that is not on a Form S-3 or other comparable form or (B) for at least two years (excluding any Interruption Period or Delay Period) in the case of a Demand Registration on Form S-3 or other comparable form, or until the completion of the distribution of the Registrable Securities thereunder, whichever is earlier (including, without limitation, because of withdrawal of such Registration Statement by the Holders pursuant to Section 2(f) hereunder), (ii) if, after it has become effective, such registration is interfered with for any reason by any stop

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order, injunction or other order or requirement of the Commission or any governmental authority, or as a result of the initiation of any proceeding for such stop order by the Commission through no fault of the Holders and the result of such interference is to prevent the Holders from disposing of such Registrable Securities proposed to be sold in accordance with the intended methods of disposition, or (iii) if the conditions to closing specified in the purchase agreement or underwriting agreement entered into in connection with any underwritten offering shall not be satisfied or waived with the consent of the Holders of a majority in number of the Registrable Securities to be included in such Demand Registration, other than as a result of any breach by the Holders or any underwriter of its obligations thereunder or hereunder.

(c) Registration Statement. Subject to paragraph (a) above, as soon as practicable, but in any event within 45 days of the date on which the Company first receives one or more Demand Notices pursuant to Section 2(a) hereof, the Company shall file with the Commission a Registration Statement on the appropriate form for the registration and sale of the total number of Registrable Securities specified in such Demand Notice, together with the number of Registrable Securities requested to be included in the Demand Registration by other Holders, in accordance with the intended method or methods of distribution specified by the Holders in such Demand Notice. The Company shall use its best efforts to cause such Registration Statement to be declared effective by the Commission as soon as reasonably practicable.

(d) Amendments; Supplements. Subject to Section 4(a), upon the occurrence of any event that would cause the Registration Statement (A) to contain a material misstatement or omission or (B) to be not effective and usable for resale of Registrable Securities during the period that such Registration Statement is required to be effective and usable, the Company shall file an amendment to the Registration Statement as soon as reasonably practicable, in the case of clause (A), correcting any such misstatement or omission and, in the case of either clause (A) or (B), use its best efforts to cause such amendment to be declared effective and such Registration Statement to become usable as soon as reasonably practicable thereafter.

(e) Effectiveness. The Company agrees to use its best efforts to keep any Registration Statement filed pursuant to this Section 2 continuously effective and usable for the sale of Registrable Securities until the earlier of (i) (a) in the case of a Demand Registration for delayed or continuous offerings of Registrable Securities filed on Form S-3 or another comparable form, two years after the date on which the Commission declares such Registration Statement effective (excluding any Interruption Period or Delay Period) or (b) in the case of a Demand Registration that is not on Form S-3 or another comparable form, 180 days from the date on which the Commission declares such Registration Statement effective (excluding any Interruption Period or Delay Period) and (ii) the date on which there are no longer any Registrable Securities.

(f) Holders Withdrawal. Holders of a majority in number of the Registrable Securities to be included in a Demand Registration pursuant to this Section 2 may, at any time prior to the effective date of the Registration Statement in respect thereof, revoke such request by providing a written notice to the Company to such effect.

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(g) Preemption of Demand Registration. Notwithstanding anything to the contrary contained herein, after receiving a written request for a Demand Registration, the Company may elect to effect an underwritten primary registration in lieu of the Demand Registration if the Company’s Board of Directors believes that such primary registration would be in the best interests of the Company. If the Company so elects to effect a primary registration, the Company shall give prompt written notice (which shall be given not later than 20 days after the date of the Demand Notice) to all Holders of its intention to effect such a registration and shall afford the Holders the rights contained in Section 3 with respect to Piggyback Registrations. In the event that the Company so elects to effect a primary registration after receiving a request for a Demand Registration, the Company shall use its best efforts to have the Registration Statement declared effective by the Commission as soon as reasonably practicable. In addition, the request for a Demand Registration shall be deemed to have been withdrawn and such primary registration shall not be deemed to be a Demand Registration.

(h) Priority on Demand Registrations. If a Demand Registration is an underwritten offering and includes securities for sale by the Company, and the managing underwriter (such underwriter to be chosen by Holders of a majority of the Registrable Securities included in such registration, subject to the Company’s reasonable approval) advises the Company, in writing, that, in its good faith judgment, the number of securities requested to be included in such registration exceeds the number which can be sold in such offering without materially and adversely affecting the marketability of the offering, then the Company will include in any such registration the maximum number of shares that the managing underwriter advises the Company can be sold in such offering allocated as follows: (i) first, the Registrable Securities requested to be included in such registration by the initiating Holders and securities of other Holders of Registrable Securities, with such securities to be included on a pro rata basis (or in such other proportion mutually agreed among such Holders) based on the amount of securities requested to be included therein and (ii) second, to the extent that any other securities may be included without exceeding the limitations recommended by the underwriter as aforesaid, the securities that the Company proposes to sell. If the initiating Holders are not allowed to register all of the Registrable Securities requested to be included by such Holders because of allocations required by this section, such initiating Holders shall not be deemed to have exercised a Demand Registration for purposes of Section 2(b).

Section 3. Piggyback Registrations.

(a) Right to Piggyback Registrations. Whenever the Company or another party having registration rights proposes that the Company register any of the Company’s equity securities under the Securities Act (other than a registration on Form S-4 relating solely to a transaction described in Rule 145 of the Securities Act or a registration on Form S-8 or any successor forms thereto), whether or not for sale for the Company’s own account, the Company will give prompt written notice of such proposed filing to all Holders at least 30 days before the anticipated filing date. Such notice shall offer such Holders the opportunity to register such amount of Registrable Securities as they shall 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 inclusion therein within 20 days after such notice has been given by the Company to the Holders. If the Registration Statement relating to the Piggyback Registration is for an underwritten

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offering, such Registrable Securities shall be included in the underwriting on the same terms and conditions as the securities otherwise being sold through the underwriters. Each Holder shall be permitted to withdraw all or part of the Registrable Securities from a Piggyback Registration at any time prior to the effective time of such Piggyback Registration.

(b) Priority on Piggyback Registrations. If a Piggyback Registration is an underwritten offering by or through one or more underwriters of recognized standing and the managing underwriters advise the party or parties initiating such offering in writing (a copy of which writing shall be provided to the Holders) that in their good faith judgment the number of securities requested to be included in such registration exceeds the number which can be sold in such offering without materially and adversely affecting the marketability of the offering, then any such registration shall include the maximum number of shares that such managing underwriters advise can be sold in such offering allocated as follows: (i) first, the securities the party or parties initiating such offering propose to sell, and (ii) second, to the extent that any other securities may be included without exceeding the limitations recommended by the underwriters as aforesaid, (x) if the Company has initiated such offering, the Registrable Securities to be included in such registration by the Holders, with such additional securities to be included on a pro rata basis (or in such other proportion mutually agreed among the Holders and such other holders), based on the amount of Registrable Securities and other securities requested to be included therein, and (y) if a party other than the Company initiated such offering (subject to Section 3(b)(i) above), securities proposed to be sold by the Company, and the Registrable Securities to be included in such registration by the Holders, with such additional securities to be included on a pro rata basis (or in such other proportion mutually agreed among the Company, the Holders and such other holders), based on the amount of Registrable Securities and other securities requested to be included therein.

Section 4. Obligations of the Company.

(a) Delay Period. Notwithstanding the foregoing, the Company shall have the right to delay the filing of any Registration Statement otherwise required to be prepared and filed by the Company pursuant to Sections 2 or 3, or to suspend the use of any Registration Statement, for a period not in excess of 60 consecutive calendar days (a “Delay Period”) if (i) the Board of Directors of the Company by written resolution determines that filing or maintaining the effectiveness of such Registration Statement would have a material adverse effect on the Company or the holders of its capital stock in relation to any material acquisition or disposition, financing or other corporate transaction or (ii) the Board of Directors of the Company by written resolution determines in good faith that the filing of a Registration Statement or maintaining the effectiveness of a current Registration Statement would require disclosure of material information that the Company has a valid business purpose for retaining as confidential at such time. The Company shall not be entitled to exercise a Delay Period more than one time in any 12-month period.

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(b) Registration Procedures. Whenever the Company is required to register Registrable Securities pursuant to Sections 2 or 3 hereof, the Company will use its best efforts to effect the registration to permit the sale of such Registrable Securities in accordance with the intended method or methods of disposition thereof, and pursuant thereto the Company will as expeditiously as possible:

(1) prepare and file with the Commission a Registration Statement with respect to such Registrable Securities as prescribed by Sections 2 or 3 on a form available for the sale of the Registrable Securities by the holders thereof in accordance with the intended method or methods of distribution thereof and use its best efforts to cause each such Registration Statement to become and remain effective within the time periods and otherwise as provided herein;

(2) prepare and file with the Commission such amendments (including post-effective amendments) to the Registration Statement and such supplements to the Prospectus as may be necessary to keep such Registration Statement effective and to comply with the provisions of the Securities Act with respect to the disposition of all securities covered by such Registration Statement until such time as all of such securities have been disposed of in accordance with the intended methods of disposition by the seller or sellers thereof set forth in such Registration Statement;

(3) furnish to each selling Holder of Registrable Securities covered by a Registration Statement and to each underwriter, if any, such number of copies of such Registration Statement, each amendment and post-effective amendment thereto, the Prospectus included in such Registration Statement (including each preliminary prospectus and any supplement to such Prospectus and any other prospectus filed under Rule 424 of the Securities Act), in each case including all exhibits, and such other documents as such Holder may reasonably request in order to facilitate the disposition of the Registrable Securities owned by such Holder or to be disposed of by such underwriter (the Company hereby consenting to the use in accordance with all applicable law of each such Registration Statement (or amendment or post-effective amendment thereto) and each such Prospectus (or preliminary prospectus or supplement thereto) by each such Holder and the underwriters, if any, in connection with the offering and sale of the Registrable Securities covered by such Registration Statement or Prospectus);

(4) use its best efforts to register or qualify and, if applicable, to cooperate with the selling Holders, the underwriters, if any, and their respective counsel in connection with the registration or qualification (or exemption from such registration or qualification) of, the Registrable Securities for offer and sale under the securities or blue sky laws of such jurisdictions as any selling Holder or managing underwriters (if any) shall reasonably request, 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 do any and all other acts or things necessary or advisable to enable the disposition in such jurisdictions of the securities covered by the applicable Registration Statement; provided, that, the Company will not be required to (i) qualify generally to do business in any jurisdiction where it would not otherwise be required to qualify but for this paragraph or (ii) consent to general service of process or taxation in any such jurisdiction where it is not so subject;

(5) cause all such Registrable Securities to be listed or quoted (as the case may be) on each national securities exchange or other securities market on which securities of the same class as the Registrable Securities are then listed or quoted;

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(6) provide a transfer agent and registrar for all such Registrable Securities and a CUSIP number for all such Registrable Securities not later than the effective date of such Registration Statement;

(7) comply with all applicable rules and regulations of the Commission, and make available to its security holders an earnings statement 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 45 days after the end of any 12-month period (or 90 days after the end of any 12-month period if such period is a fiscal year) (or in each case within such extended period of time as may be permitted by the Commission for filing the applicable report with the Commission) (i) commencing at the end of any fiscal quarter in which Registrable Securities are sold to underwriters in an underwritten offering or (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;

(8) use its best efforts to prevent the issuance of any order suspending the effectiveness of a Registration Statement or suspending the qualification (or exemption from qualification) of any of the Registrable Securities included therein for sale in any jurisdiction, and, in the event of the issuance of any stop order suspending the effectiveness of a Registration Statement, or of any order suspending the qualification of any Registrable Securities included in such Registration Statement for sale in any jurisdiction, the Company will use its best efforts promptly to obtain the withdrawal of such order at the earliest possible moment;

(9) obtain “cold comfort” letters and updates thereof (which letters and updates (in form, scope and substance) shall be reasonably satisfactory to the managing underwriters, if any, and the Holders) 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), addressed to each of the underwriters, if any, and each selling Holder of Registrable Securities, such letters to be in customary form and covering matters of the type customarily covered in “cold comfort” letters in connection with underwritten offerings and such other matters as the underwriters, if any, or the Holders of a majority of the Registrable Securities being included in the registration may reasonably request;

(10) obtain opinions of independent counsel to the Company and updates thereof (which counsel and opinions (in form, scope and substance) shall be reasonably satisfactory to the managing underwriters, if any, and the Holders of a majority of the Registrable Securities being included in the registration), addressed to each selling Holder and each of the underwriters, if any, covering the matters customarily covered in opinions of issuer’s counsel requested in underwritten offerings, such as the effectiveness of the Registration Statement and such other matters as may be requested by such counsel and underwriters, if any;

(11) promptly notify the selling Holders and the managing underwriters, if any, and confirm such notice in writing, when a Prospectus or any supplement or post-effective amendment to such Prospectus has been filed, and, with respect to a Registration Statement or any post-effective amendment thereto, when the same has become effective, of any

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request by the Commission or any other federal or state governmental authority for amendments or supplements to a Registration Statement or related Prospectus or for additional information, of the issuance by the Commission of any stop order suspending the effectiveness of a Registration Statement or of any order preventing or suspending the use of any Prospectus or the initiation of any proceedings by any Person for that purpose, of the receipt by the Company of any notification with respect to the suspension of the qualification or exemption from qualification of a Registration Statement or any of the Registrable Securities for offer or sale under the securities or blue sky laws of any jurisdiction, or the contemplation, initiation or threatening, of any proceeding for such purpose, and of the happening of any event or the existence of any facts that make any statement made in such Registration Statement or Prospectus untrue in any material respect or that require the making of any changes in such Registration Statement or Prospectus so that 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 light of the circumstances under which they were made (in the case of any Prospectus), not misleading (which notice shall be accompanied by an instruction to the selling Holders and the managing underwriters, if any, to suspend the use of the Prospectus until the requisite changes have been made);

(12) if requested by the managing underwriters, if any, or a Holder of Registrable Securities being sold, promptly incorporate in a prospectus, supplement or post-effective amendment such information as the managing underwriters, if any, and the Holders of a majority of the Registrable Securities being sold reasonably request to be included therein relating to the sale of the Registrable Securities, including, without limitation, information with respect to the number of shares of Registrable Securities being sold to underwriters, the purchase price being paid therefor by such underwriters and with respect to any other terms of the underwritten offering of the Registrable Securities to be sold in such offering, and make all required filings of such prospectus, supplement or post-effective amendment promptly following notification of the matters to be incorporated in such supplement or post-effective amendment;

(13) if requested, furnish to each selling Holder of Registrable Securities and the managing underwriter, without charge, at least one signed copy of the Registration Statement;

(14) as promptly as practicable upon the occurrence of any event contemplated by Section 4(b)(11) above, prepare a supplement or post-effective amendment to the Registration Statement or the Prospectus, or any document incorporated therein by reference, or file any other required document so that, as thereafter delivered to the purchasers of the Registrable Securities being sold hereunder, the Prospectus will not contain an untrue statement of a material fact or an omission to state a material fact required to be stated in a Registration Statement or Prospectus or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading; and

(15) if such offering is an underwritten offering, enter into such agreements (including an underwriting agreement in form, scope and substance as is customary in underwritten offerings) and take all such other appropriate and reasonable actions requested by the Holders owning a majority of the Registrable Securities being sold in connection therewith or by the managing underwriters (including cooperating in reasonable marketing efforts, including

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in connection with any Demand Registration, participation by senior executives of the Company in any “roadshow” or similar meeting with potential investors) in order to expedite or facilitate the disposition of such Registrable Securities, and in such connection, provide indemnification provisions and procedures substantially to the effect set forth in Section 6 hereof with respect to all parties to be indemnified pursuant to said Section. The above shall be done at each closing under such underwriting or similar agreement, or as and to the extent required thereunder.

Each Holder agrees by acquisition of such Registrable Securities that, upon receipt of written notice from the Company of the happening of any event of the kind described in Section 4(b)(11), such Holder will forthwith discontinue disposition of such Registrable Securities covered by such Registration Statement until such Holder’s receipt of the copies of the supplemented or amended Registration Statement contemplated by Section 4(b)(14), or until it is advised in writing by the Company that the use of the applicable Prospectus may be resumed, and has received copies of any additional or supplemental filings that are incorporated or deemed to be incorporated by reference in such prospectus (such period during which disposition is discontinued being an “Interruption Period”), and, if so directed by the Company, such Holder will deliver to the Company all copies of the Prospectus covering such Registrable Securities current at the time of receipt of such notice.

Section 5. Registration Expenses.

(a) Expenses Payable by the Company. The Company shall bear all expenses incurred with respect to the registration or attempted registration of the Registrable Securities pursuant to Sections 2 or 3 of this Agreement as provided herein. Such expenses shall include, without limitation, (i) all registration, qualification and filing fees (including, without limitation, (A) fees with respect to compliance with the Commission, (B) fees with respect to filings required to be made with the national securities exchange or national market system on which the Common Stock is then traded or quoted and (C) fees and expenses of compliance with state securities or blue sky laws (including, without limitation, fees and disbursements of counsel for the Company or the underwriters, or both, in connection with blue sky qualifications of Registrable Securities)), (ii) messenger and delivery expenses, word processing, duplicating and printing expenses (including without limitation, expenses of printing certificates for Registrable Securities in a form eligible for deposit with The Depository Trust Company, printing preliminary prospectuses, prospectuses, prospectus supplements, including those delivered to or for the account of the Holders and provided in this Agreement, and blue sky memoranda), (iii) fees and disbursements of counsel for the Company, (iv) fees and disbursements of all independent certificated public accountants for the Company (including, without limitation, the expense of any “comfort letters” required by or incident to such performance), (v) all out-of-pocket expenses of the Company (including without limitation, expenses incurred by the Company, its officers, directors, and employees performing legal or accounting duties or preparing or participating in “roadshow” presentations or of any public relations, investor relations or other consultants or advisors retained by the Company in connection with any roadshow, including travel and lodging expenses of such roadshows), (vi) fees and expenses incurred in connection with the quotation or listing of shares of Common Stock on any national securities exchange or other securities market, and (vii) reasonable fees and expenses of one firm of counsel for all selling Holders (which shall be chosen by the Holders of a majority of Registrable Securities to be included in such offering).

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(b) Expenses Payable by the Holders. Each Holder shall pay all underwriting discounts and commissions or placement fees of underwriters or broker’s commissions incurred in connection with the sale or other disposition of Registrable Securities for or on behalf of such Holder’s account.

Section 6. Indemnification.

(a) Indemnification by the Company. The Company agrees to indemnify, to the fullest extent permitted by law, each Holder, each affiliate of a Holder and each director, officer, employee, manager, stockholder, partner, member, counsel, agent or representative of such Holder and its affiliates and each Person who controls any such Person (within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act) (collectively, “Holder Indemnified Parties”) against, and hold it and them harmless from, all losses, claims, damages, liabilities, actions, proceedings, costs (including, without limitation, costs of preparation and attorneys’ fees and disbursements) and expenses, including expenses of investigation and amounts paid in settlement (collectively, “Losses”) arising out of, caused by or based upon any untrue or alleged untrue statement of material fact contained in any Registration Statement, or any omission or alleged omission of a material fact required to be stated therein or necessary to make the statements therein not misleading (a “Misstatement/Omission”), or any violation or alleged violation by the Company of the Securities Act, the Exchange Act, any state securities law, or any rule or regulation promulgated under the Securities Act, the Exchange Act or any state securities law, except that the Company shall not be liable insofar as such Misstatement/Omission or violation is made in reliance upon and in conformity with information furnished in writing to the Company by such Holder expressly for use therein; provided, further, that the Company shall not be liable for a Holder’s failure to deliver or cause to be delivered (to the extent such delivery is required under the Securities Act) the Prospectus contained in the Registration Statement, furnished to it by the Company on a timely basis at or prior to the time such action is required by the Securities Act to the person claiming a Misstatement/Omission if such Misstatement/Omission was corrected in such Prospectus. In connection with an underwritten offering, the Company will indemnify such underwriters, selling brokers, dealer managers and similar securities industry professionals participating in the distribution, their officers and directors and each Person who controls such underwriters (within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act) to the same extent as provided above with respect to the indemnification of the Holders. This indemnity shall be in addition to any other indemnification arrangements to which the Company may otherwise be party.

(b) Indemnification by the Holders. In connection with any Registration Statement in which a Holder is participating, each such Holder agrees to indemnify, to the fullest extent permitted by law, the Company and each director and officer of the Company and each Person who controls the Company (within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act) against, and hold it harmless from, any Losses arising out of or based upon (i) any Misstatement/Omission contained in the Registration Statement, if and to the extent that such Misstatement/Omission was made in reliance upon and in conformity with information furnished in writing by such Holder for use therein, or (ii) the failure by such Holder to deliver or cause to be delivered (to the extent such delivery is required under the Securities Act) the Prospectus contained in the Registration Statement, furnished to it by the Company on a

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timely basis at or prior to the time such action is required by the Securities Act to the person claiming a Misstatement/Omission if such Misstatement/Omission was corrected in such Prospectus. Notwithstanding the foregoing, the obligation to indemnify will be individual (several and not joint) to each Holder and will be limited to the net amount of proceeds (net of payment of all expenses) received by such Holder from the sale of Registrable Securities pursuant to such Registration Statement giving rise to such indemnification obligation.

(c) Conduct of Indemnification Proceedings. In case any action, claim or proceeding shall be brought against any Person entitled to indemnification hereunder, such indemnified party shall promptly notify each indemnifying party in writing, and such indemnifying party shall assume the defense thereof, including the employment of one counsel reasonably satisfactory to such indemnified party and payment of all fees and expenses incurred in connection with the defense thereof. The failure to so notify such indemnifying party shall relieve such indemnifying party of its indemnification obligations to such indemnified party to the extent that such failure to notify materially prejudiced such indemnifying party but not from any liability that it or they may have to the indemnified party for contribution or otherwise. Each indemnified party shall have the right to employ separate counsel in such action, claim or proceeding and participate in the defense thereof, but the fees and expenses of such counsel shall be at the expense of each indemnified party unless: (i) such indemnifying party has agreed to pay such expenses; (ii) such indemnifying party has failed promptly to assume the defense and employ counsel reasonably satisfactory to such indemnified party; or (iii) the named parties to any such action, claim or proceeding (including any impleaded parties) include both such indemnified party and such indemnifying party or an affiliate or controlling person of such indemnifying party, and such indemnified party shall have been advised in writing by counsel that either (x) there may be one or more legal defenses available to it which are different from or in addition to those available to such indemnifying party or such affiliate or controlling person or (y) a conflict of interest may exist if such counsel represents such indemnified party and such indemnifying party or its affiliate or controlling person; provided, however, that such indemnifying party shall not, in connection with any one such action or proceeding or separate but substantially similar or related actions or proceedings in the same jurisdiction arising out of the same general allegations or circumstances, be responsible hereunder for the fees and expenses of more than one separate firm of attorneys (in addition to any local counsel), which counsel shall be designated by such indemnified party or, in the event that such indemnified party is a Holder Indemnified Party, by the Holders of a majority of the Registrable Securities included in the subject Registration Statement.

No indemnifying party shall be liable for any settlement effected without its written consent (which consent may not be unreasonably delayed or withheld). Each indemnifying party agrees that it will not, without the indemnified party’s prior written consent, consent to entry of any judgment or settle or compromise any pending or threatened claim, action or proceeding in respect of which indemnification or contribution may be sought hereunder unless the foregoing contains an unconditional release, in form and substance reasonably satisfactory to the indemnified parties, of the indemnified parties from all liability and obligation arising therefrom. The indemnifying party’s liability to any such indemnified party hereunder shall not be extinguished solely because any other indemnified party is not entitled to indemnity hereunder.

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(d) Survival. The indemnification provided for under this Agreement will (i) remain in full force and effect regardless of any investigation made by or on behalf of the indemnified party or any officer, director or controlling Person of such indemnified party, (ii) survive the transfer of securities and (iii) survive the termination of this Agreement.

(e) Right to Contribution. If the indemnification provided for in this Section 6 is unavailable to, or insufficient to hold harmless, an indemnified party under Section 6(a) or Section 6(b) above in respect of any Losses referred to in such Sections, then each applicable indemnifying party shall have an obligation to contribute to the amount paid or payable by such indemnified party as a result of such Losses in such proportion as is appropriate to reflect the relative fault of the Company, on the one hand, and of the Holder, on the other, in connection with the Misstatement/Omission or violation which resulted in such Losses, taking into account any other relevant equitable considerations. The amount paid or payable by a party as a result of the Losses referred to above shall be deemed to include, subject to the limitations set forth in Section 6(c) above, any legal or other fees or expenses reasonably incurred by such party in connection with any investigation, lawsuit or legal or administrative action or proceeding.

The relative fault of the Company, on the one hand, and of the Holder, on the other, shall be determined by reference to, among other things, whether the relevant Misstatement/Omission or violation relates to information supplied by the Company or by the Holder and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such Misstatement/Omission or violation.

The Company and each Holder agree that it would not be just and equitable if contribution pursuant to this Section 6(e) were determined by pro rata allocation or by any other method of allocation which does not take account of the equitable considerations referred to above. Notwithstanding the provisions of this Section 6(e), a Holder shall not be required to contribute any amount in excess of the amount by which (i) the amount (net of payment of all expenses) at which the securities that were sold by such Holder and distributed to the public were offered to the public exceeds (ii) the amount of any damages which such Holder has otherwise been required to pay by reason of such Misstatement/Omission or violation.

No Person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any Person who was not guilty of such fraudulent misrepresentation.

Section 7. Rules 144 and 144A.

The Company shall timely file the reports required to be filed by it under the Securities Act and the Exchange Act (including but not limited to the reports under Sections 13 and 15(d) of the Exchange Act referred to in subparagraph (c) of Rule 144 adopted by the Commission under the Securities Act) and the rules and regulations adopted by the Commission thereunder (or, if the Company is not required to file such reports, it will, upon the request of any Holder, make publicly available other information) and will take such further action as any Holder may reasonably request, all to the extent required from time to time to enable such Holder to sell Registrable Securities without registration under the Securities Act within the limitation of the exemptions provided by (a) Rule 144 and Rule 144A under the Securities Act, as such Rules may be amended from time to time, or (b) any similar rule or regulation hereafter adopted by the Commission.

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Section 8. Underwritten Registrations.

(a) No Person may participate in any registration hereunder which is underwritten unless such Person (i) agrees to sell such Person’s securities on the basis provided in any underwriting arrangements approved by the Person or Persons entitled hereunder to approve such arrangements and (ii) completes and executes all questionnaires, powers of attorney, customary indemnities, underwriting agreements and other documents required under the terms of such underwriting arrangements; provided, that, no Holder included in any underwritten registration shall be required to make any representations or warranties to the Company or the underwriters other than representations and warranties regarding such Holder and such Holder’s intended method of distribution.

(b) If any of the Registrable Securities covered by any Registration Statement are to be sold in an underwritten offering, the investment banker or investment bankers and manager or managers that will manage the offering will be selected by, and the underwriting arrangements with respect thereto will be approved by, the Company; provided, however, that such investment bankers and managers and underwriting arrangements must be reasonably satisfactory to the Holders of the majority of Registrable Securities to be included in such offering.

Section 9. Covenants of Holders.

Each of the Holders hereby agrees (a) to cooperate with the Company and to furnish to the Company all such information regarding such Holder, its ownership of Registrable Securities and the disposition of such securities in connection with the preparation of the Registration Statement and any filings with any state securities commissions as the Company may reasonably request, (b) to the extent required by the Securities Act, to deliver or cause delivery of the Prospectus contained in the Registration Statement, any amendment or supplement thereto, to any purchaser of the Registrable Securities covered by the Registration Statement from the Holder and (c) if requested by the Company, to notify the Company of any sale of Registrable Securities by such Holder.

Section 10. Miscellaneous.

(a) No Inconsistent Agreements. The Company will not hereafter enter into any agreement with respect to its securities that is inconsistent with, adversely effects or violates the rights granted to the Holders in this Agreement; it being understood that the granting of additional demand or piggyback registration rights with respect to capital stock of the Company shall not be deemed adverse to the rights granted to Holders hereunder so long as they do not (x) reduce the amount of Registrable Securities that any Holder may include in any registration contemplated in this Agreement or (y) restrict or otherwise limit the exercise by any Holder of its rights hereunder.

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(b) Remedies. Any Person having rights under any provision of this Agreement will be entitled to enforce such rights specifically to recover damages caused by reason of any breach of any provision of this Agreement and to exercise all other rights granted by law. The parties hereto agree and acknowledge that money damages may not be an adequate remedy for any breach of the provisions of this Agreement and hereby agree to waive the defense in any action for specific performance or injunctive relief that a remedy at law would be adequate. Accordingly, any party may in its sole discretion apply to any court of law or equity of competent jurisdiction (without posting any bond or other security) for specific performance and for other injunctive relief in order to enforce or prevent violation of the provisions of this Agreement.

(c) Amendments and Waivers. Except as otherwise provided herein, the provisions of this Agreement, including the provisions of this sentence, may be amended, modified, supplemented or waived only upon the prior written consent of the Company and Holders of a majority of the outstanding Registrable Securities.

(d) Successors and Assigns. This Agreement shall be binding upon and inure to the benefit of the parties hereto and their respective successors and assigns. The Holders may assign all rights under this agreement; provided, however, that no Holder may transfer or assign its rights hereunder unless such transferring Holder shall, prior to any such transfer, obtain from the transferee a joinder agreement in a form reasonably satisfactory to the Company and deliver a copy of such joinder agreement to the Company and to the Holders. Only persons (other than the initial Stockholder hereto) that execute a joinder agreement shall be deemed to be Holders (“Permitted Transferee”). The Company shall be given written notice by the transferring Holder at the time of the transfer stating the name and address of the transferee and identifying the Registrable Securities transferred, provided, that, failure to give such notice shall not affect the validity of such transfer or assignment.

(e) Termination of Registration Rights. The rights of any Holder to cause the Company to register Registrable Securities under this Agreement shall terminate with respect to such Holder as soon as such Holder is legally able to dispose of all of its Registrable Securities in one transaction pursuant to Rule 144 under the Securities Act.

(f) Severability. In the event that any one or more of the provisions contained herein, or the application thereof in any circumstances, is held invalid, illegal or unenforceable in any respect for any reason, the validity, legality and enforceability of any such provision in every other respect and of the remaining provisions hereof shall not be in any way impaired or affected, it being intended that the rights and privileges of the parties hereto shall be enforceable to the fullest extent permitted by law.

(g) Counterparts. This Agreement may be executed in any number of counterparts, any one of which need not contain the signatures of more than one party, but each of which when so executed shall be deemed to be an original and all such counterparts taken together shall constitute one and the same Agreement.

(h) Descriptive Headings: Interpretation. The descriptive headings of this Agreement are inserted for convenience of reference only and shall not limit or otherwise affect the meaning hereof. The use of the word “including” in this Agreement shall be by way of example rather than by limitation.

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(i) Notices. All notices, requests and other communications provided for or permitted to be given under this Agreement must be in writing and shall be given by personal delivery, by certified or registered United States mail (postage prepaid, return receipt requested), by a nationally recognized overnight delivery service for next day delivery, or by facsimile transmission, as follows (or to such other address as any party may give in a notice given in accordance with the provisions hereof):

If to the Company:

Bronco Drilling Company, Inc.

14313 North May Avenue

Suite 100

Oklahoma City, OK 73134

Attention: Chief Executive Officer

Facsimile: (405) 848-8816

with a copy (which shall not constitute notice) to:

Akin Gump Strauss Hauer & Feld LLP

1700 Pacific Avenue

Suite 4100

Dallas, TX 75201

Attention: Seth R. Molay, P.C.

Facsimile: (214) 969-4343

If to the Stockholder:

Wexford Capital LLC

411 West Putnam Avenue

Greenwich, CT 06830

Attention: Arthur Amron

Facsimile: (203) 862-7312

All notices, requests or other communications will be effective and deemed given only as follows: (i) if given by personal delivery, upon such personal delivery, (ii) if sent by certified or registered mail, on the fifth business day after being deposited in the United States mail, (iii) if sent for next day delivery by overnight delivery service, on the date of delivery as confirmed by written confirmation of delivery, (iv) if sent by facsimile, upon the transmitter’s confirmation of receipt of such facsimile transmission, except that if such confirmation is received after 5:00 p.m. (in the recipient’s time zone) on a business day, or is received on a day that is not a business day, then such notice, request or communication will not be deemed effective or given until the next succeeding business day. Notices, requests and other communications sent in any other manner, including by electronic mail, will not be effective.

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(j) GOVERNING LAW; SUBMISSION TO JURISDICTION. THIS AGREEMENT SHALL BE DEEMED TO BE MADE IN AND IN ALL RESPECTS SHALL BE INTERPRETED, CONSTRUED AND GOVERNED BY AND IN ACCORDANCE WITH THE LAW OF THE STATE OF DELAWARE WITHOUT REGARD TO THE CONFLICT OF LAW PRINCIPLES THEREOF. The parties hereby irrevocably submit to the jurisdiction of any federal court located in the State of Delaware or any Delaware state court solely in respect of the interpretation and enforcement of the provisions of this Agreement and of the documents referred to in this Agreement, and in respect of the transactions contemplated hereby, and hereby waive, and agree not to assert, as a defense in any action, suit or proceeding for the interpretation or enforcement hereof or of any such document, that it is not subject thereto or that such action, suit or proceeding may not be brought or is not maintainable in said courts or that the venue thereof may not be appropriate or that this Agreement or any such document may not be enforced in or by such courts, and the parties hereto irrevocably agree that all claims with respect to such action or proceeding shall be heard and determined in such a Delaware state or federal court. The parties hereby consent to and grant any such court jurisdiction over the person of such parties and over the subject matter of such dispute and agree that mailing of process or other papers in connection with any such action or proceeding in the manner provided in the Section on notices above or in such other manner as may be permitted by law shall be valid and sufficient service thereof.

EACH PARTY ACKNOWLEDGES AND AGREES THAT ANY CONTROVERSY WHICH MAY ARISE UNDER THIS AGREEMENT IS LIKELY TO INVOLVE COMPLICATED AND DIFFICULT ISSUES, AND THEREFORE EACH SUCH PARTY HEREBY IRREVOCABLY AND UNCONDITIONALLY WAIVES ANY RIGHT SUCH PARTY MAY HAVE TO A TRIAL BY JURY IN RESPECT OF ANY LITIGATION DIRECTLY OR INDIRECTLY ARISING OUT OF OR RELATING TO THIS AGREEMENT, OR THE TRANSACTIONS CONTEMPLATED BY THIS AGREEMENT. EACH PARTY CERTIFIES AND ACKNOWLEDGES THAT (I) NO REPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER, (II) EACH PARTY UNDERSTANDS AND HAS CONSIDERED THE IMPLICATIONS OF THIS WAIVER, (III) EACH PARTY MAKES THIS WAIVER VOLUNTARILY, AND (IV) EACH PARTY HAS BEEN INDUCED TO ENTER INTO THIS AGREEMENT BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS IN THIS SECTION.

(k) Entire Agreement. This Agreement is intended by the parties as a final expression of their agreement and intended to be a complete and exclusive statement of the agreement and understanding of the parties hereto in respect of the subject matter contained herein. This Agreement supersedes all prior agreements and understandings between the parties with respect to such subject matter.

[Signature Page Follows]

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