Exhibit 4.1

UNIT CORPORATION

and

WILMINGTON TRUST FSB

as Trustee

Indenture

Dated as of May 18, 2011

Debt Securities

TABLE OF CONTENTS

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INDENTURE dated as of May 18, 2011 between UNIT CORPORATION, a corporation duly organized and existing under the laws of the State of Delaware (hereinafter sometimes called the “ Company ”), and WILMINGTON TRUST FSB, a federal savings bank (hereinafter sometimes called the “ Trustee ”).

RECITALS OF THE COMPANY

The Company has duly authorized the execution and delivery of this Indenture to provide for the issuance from time to time of its debentures, notes, bonds or other evidences of indebtedness to be issued in one or more series unlimited as to principal amount (herein called the “ Debt Securities ”), as in this Indenture provided.

All things necessary to make this Indenture a valid agreement of the Company, in accordance with its terms, have been done.

NOW, THEREFORE, THIS INDENTURE WITNESSETH

That in order to declare the terms and conditions upon which the Debt Securities are authenticated, issued and delivered, and in consideration of the premises, and of the purchase and acceptance of the Debt Securities by the holders thereof, the Company and the Trustee covenant and agree with each other, for the benefit of the respective Holders from time to time of the Debt Securities or any series thereof, as follows:

ARTICLE 1

D EFINITIONS

Section 1.01 . Certain Terms Defined. The terms defined in this Section 1.01 (except as herein otherwise expressly provided or unless the context otherwise requires) for all purposes of this Indenture and of any Indenture supplemental hereto shall have the respective meanings specified in this Section 1.01. All other terms used in this Indenture which are defined in the Trust Indenture Act or which are by reference therein defined in the Securities Act (except as herein otherwise expressly provided or unless the context otherwise requires), shall have the meanings assigned to such terms in the Trust Indenture Act and in the Securities Act as in force as of the date of original execution of this Indenture.

“ Affiliate ” of any specified Person means any other Person, directly or indirectly, controlling or controlled by or under direct or indirect common control with such specified Person. For the purposes of this definition, “ control ” when used with respect to any Person means the power to direct the management and policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise; and the terms “ controlling ” and “ controlled ” have meanings correlative to the foregoing.

“ Bank Indebtedness ” means any and all amounts payable under or in respect of (i) the Credit Agreement, as supplemented, amended, modified, refinanced or replaced at any time from time to time, and (ii) any lines of credit and letters of credit of the Company, in each case, including principal, premium (if any), interest (including interest accruing on or after the filing of any petition in bankruptcy or for reorganization relating to the Company whether or not a claim for post-filing interest is allowed in such proceedings), fees, charges, expenses, reimbursement obligations, guarantees and all other amounts payable thereunder or in respect thereof.

“ Banks ” has the meaning specified in the Credit Agreement.

“ Board of Directors ” means either the Board of Directors of the Company or any duly authorized committee or subcommittee of such Board, except as the context may otherwise require.

“ business day ” means any day that is not a Saturday, a Sunday or legal holiday and, with respect to any Place of Payment specified pursuant to Section 2.03, any other day on which banking institutions or trust companies in such Place of Payment are authorized or obligated by law or executive order to close.

“ Cash Equivalents ” means:

(i) securities issued or directly and fully guaranteed or insured by the United States Government or any agency or instrumentality of the United States (provided that the full faith and credit of the United States is pledged in support thereof), having a maturity within one year after the date of acquisition thereof;

(ii) marketable general obligations issued by any state of the United States of America or any political subdivision of any such state or any public instrumentality thereof maturing within one year after the date of acquisition thereof and, at the time of such acquisition, having a credit rating of at least “A” or the equivalent thereof from either Standard & Poor’s Ratings Services or Moody’s Investors Service, Inc. (or an equivalent rating by another nationally recognized rating agency if both of the two named rating agencies cease publishing ratings of investments);

(iii) certificates of deposit, time deposits, eurodollar time deposits, overnight bank deposits or bankers’ acceptances having maturities of not more than one year after the date of acquisition thereof issued by any commercial bank the long-term debt of which is rated at the time of acquisition at least “A” or the equivalent thereof by Standard & Poor’s Ratings Services, or “A” or the equivalent thereof by Moody’s Investors Service, Inc. (or an equivalent rating by another nationally recognized rating agency if both of the two named rating agencies cease publishing ratings of investments), and having combined capital and surplus in excess of $500 million;

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(iv) repurchase obligations with a term of not more than seven days for underlying securities of the types described in clauses (i), (ii) and (iii) above entered into with any bank meeting the qualifications specified in clause (iii) above;

(v) commercial paper rated at the time of acquisition thereof at least “ A-2 ” or the equivalent thereof by Standard & Poor’s Ratings Services or “P-2” or the equivalent thereof by Moody’s Investors Service, Inc. (or an equivalent rating by another nationally recognized rating agency if both of the two named rating agencies cease publishing ratings of investments), and in any case maturing within one year after the date of acquisition thereof; and

(vi) interests in any investment company or money market fund which invests 95% or more of its assets in instruments of the type specified in clauses (i) through (v) above.

“ Capitalized Lease Obligation ” means an obligation that is required to be classified and accounted for as a capitalized lease for financial reporting purposes in accordance with GAAP; and the amount of Indebtedness represented by such obligation shall be the capitalized amount of such obligation determined in accordance with GAAP; and the Stated Maturity thereof shall be the date of the last payment of rent or any other amount due under such lease prior to the first date upon which such lease may be terminated by the lessee without payment of a penalty.

“ Capital Stock ” of any Person means any and all shares, interests, rights to purchase, warrants, options, participations or other equivalents of or interests (including partnership interests) in (however designated) equity of such Person, including any Preferred Stock, but excluding any debt securities convertible into such equity.

“ Common Stock ” means the common stock ($0.20 par value), of the Company, which stock is currently listed on the New York Stock Exchange.

“ Company ” means Unit Corporation a Delaware corporation, and, subject to the provisions of Article 10, shall also include its successors and assigns.

“ Company Order ” means a written order of the Company, signed by its Chairman of the Board, President or any Vice President and by its Treasurer, Secretary, any Assistant Treasurer or any Assistant Secretary.

“ corporate trust office of the Trustee ” or other similar term means the office of the Trustee at which the corporate trust business of the Trustee shall, at any particular time, be principally administered in the United States of America, which office is currently located at 246 Goose Lane, Suite 105, Guilford, CT 06437, Attention: Unit Corporation Administrator.

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“ Credit Agreement ” means the First Amended and Restated Senior Credit Agreement dated May 24, 2007, as may be amended from time to time, among the Company and certain of its subsidiaries, each as a Borrower, and the Banks party thereto, as supplemented, amended, modified, refinanced or replaced at any time from time to time.

“ Currency ” means Dollars or Foreign Currency.

“ Debt Security ” or “ Debt Securities ” has the meaning stated in the first recital of this Indenture and more particularly means any debt security or debt securities, as the case may be, of any series authenticated and delivered under this Indenture.

“ Debt Security Register ” has the meaning specified in Section 2.07(a).

“ Default ” means any event which is, or after notice or passage of time or both would be, an Event of Default.

“ Depositary ” means, unless otherwise specified by the Company pursuant to either Section 2.03 or 2.15, with respect to registered Debt Securities of any series issuable or issued in whole or in part in the form of one or more Global Securities, The Depository Trust Company, New York, New York, or any successor thereto registered as a clearing agency under the Exchange Act or other applicable statute or regulations.

“ Designated Senior Indebtedness ” means (i) the Bank Indebtedness and (ii) any other Senior Indebtedness.

“ Disqualified Stock ” of a Person means Redeemable Stock of such Person as to which the maturity, mandatory redemption, conversion or exchange or redemption at the option of the holder thereof occurs, or may occur, on or prior to the first anniversary of the Stated Maturity of the Debt Securities of the applicable series.

“ Dollar ” or “ $ ” means such currency of the United States as at the time of payment is legal tender for the payment of public and private debts.

“ Dollar Equivalent ” means, with respect to any monetary amount in a Foreign Currency, at any time for the determination thereof, the amount of Dollars obtained by converting such Foreign Currency involved in such computation into Dollars at the spot rate for the purchase of Dollars with the applicable Foreign Currency as quoted by Merrill Lynch, Pierce, Fenner & Smith Incorporated (unless another comparable financial institution is designated by the Company) in New York, New York at approximately 11:00 a.m. (New York time) on the date two business days prior to such determination.

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“ Event of Default ” has the meaning specified in Section 6.01.

“ Exchange Act ” means the Securities Exchange Act of 1934, as amended.

“ Floating Rate Security ” means a Debt Security that provides for the payment of interest at a variable rate determined periodically by reference to an interest rate index or formula specified pursuant to Section 2.03.

“ Foreign Currency ” means a currency issued or adopted by the government of any country other than the United States or a composite currency the value of which is determined by reference to the values of the currencies of any group of countries.

“ GAAP ” means generally accepted accounting principles in the United States as in effect as of the date on which the Debt Securities of the applicable series are issued, including those set forth in the opinions and pronouncements of the Accounting Principles Board of the American Institute of Certified Public Accountants and statements and pronouncements of the Financial Accounting Standards Board or in such other statements by such other entity as approved by a significant segment of the accounting profession. All ratios and computations based on GAAP contained in this Indenture shall be computed in conformity with GAAP consistently applied.

“ Global Security ” means, with respect to any series of Debt Securities issued hereunder, a Debt Security which is executed by the Company and authenticated and delivered by the Trustee to the Depositary or pursuant to the Depositary’s instruction, all in accordance with this Indenture and any Indentures supplemental hereto, or resolution of the Board of Directors and set forth in an officers’ Certificate, which shall be registered in the name of the Depositary or its nominee and which shall represent, and shall be denominated in an amount equal to the aggregate principal amount of, all the Outstanding Debt Securities of such series or any portion thereof, in either case having the same terms, including, without limitation, the same original issue date, date or dates on which principal is due and interest rate or method of determining interest.

“ Guarantee ” means any obligation, contingent or otherwise, of any Person directly or indirectly guaranteeing any Indebtedness or other obligation of any other Person and any obligation, direct or indirect, contingent or otherwise, of such Person (i) to purchase or pay (or advance or supply funds for the purchase or payment of) such Indebtedness or other obligation of such other Person or (ii) entered into for purposes of assuring in any other manner the obligee of such Indebtedness or other obligation of the payment thereof or to protect such obligee against loss in respect thereof (in whole or in part); provided , however , that the term “Guarantee” shall not include endorsements for collection or deposit in the ordinary course of business. The term “Guarantee” used as a verb has a corresponding meaning.

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“ Holder ,” “ Holder of Debt Securities ” or other similar terms mean, with respect to a Registered Security, the Registered Holder.

“ Incur ” means issue, assume, Guarantee, incur or otherwise become liable for; provided , however , that any Indebtedness or Capital Stock of a Person existing at the time such Person becomes a Subsidiary (whether by merger, consolidation, acquisition or otherwise) shall be deemed to be incurred by such Subsidiary at the time it becomes a Subsidiary. The terms “ Incurred ”, “ Incurrence ” and “ Incurring ” shall each have a correlative meaning.

“ Indebtedness ” means, with respect to any Person on any date of determination (without duplication),

(i) the principal of Indebtedness of such Person for borrowed money;

(ii) the principal of obligations of such Person evidenced by bonds, debentures, notes or other similar instruments;

(iii) all Capitalized Lease Obligations of such Person;

(iv) all obligations of such Person to pay the deferred and unpaid purchase price of property or services (except Trade Payables);

(v) all obligations of such Person in respect of letters of credit, banker’s acceptances or other similar instruments or credit transactions (including reimbursement obligations with respect thereto), other than obligations with respect to letters of credit securing obligations (other than obligations described in (i) through (iv) above) entered into in the ordinary course of business of such Person to the extent such letters of credit are not drawn upon or, if and to the extent drawn upon, such drawing is reimbursed no later than the third business day following receipt by such Person of a demand for reimbursement following payment on the letter of credit;

(vi) the amount of all obligations of such Person with respect to the redemption, repayment or other repurchase of any Disqualified Stock (but excluding, in each case, any accrued dividends);

(vii) all Indebtedness of other Persons secured by a Lien on any asset of such Person, whether or not such Indebtedness is assumed by such Person; provided , however , that the amount of such Indebtedness shall be the lesser of (A) the fair market value of such asset at such date of determination or (B) the amount of such Indebtedness of such other Persons; and

(viii) all Indebtedness of other Persons to the extent Guaranteed by such Person.

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For purposes of this definition, the maximum fixed redemption, repayment or repurchase price of any Disqualified Stock or Preferred Stock that does not have a fixed redemption, repayment or repurchase price shall be calculated in accordance with the terms of such Stock as if such Stock were redeemed, repaid or repurchased on any date on which Indebtedness shall be required to be determined pursuant to this Indenture; provided , however , that if such Stock is not then permitted to be redeemed, repaid or repurchased, the redemption, repayment or repurchase price shall be the book value of such Stock as reflected in the most recent financial statements of such Person. The amount of Indebtedness of any Person at any date shall be the outstanding balance at such date of all unconditional obligations as described above and the maximum liability, upon the occurrence of the contingency giving rise to the obligation, of any contingent obligations at such date.

“ Indenture ” means this instrument as originally executed, or, if amended or supplemented as herein provided, as so amended or supplemented and shall include the form and terms of particular series of Debt Securities as contemplated hereunder, whether or not a supplemental Indenture is entered into with respect thereto.

“ Issue Date ” means, with respect to any series of Debt Securities, the date upon which such Debt Securities first were issued and authenticated under this Indenture and any Indenture supplemental hereto.

“ Lien ” means any mortgage, pledge, security interest, encumbrance, lien or charge of any kind (including any conditional sale or other title retention agreement or lease in the nature thereof).

“ Officers’ Certificate ” means a certificate signed by the Chairman of the Board, the President, principal executive officer, or any Vice President and by the Treasurer, chief accounting officer, principal financial officer, the Secretary or any Assistant Treasurer or Assistant Secretary of the Company. Each such certificate shall include the statements provided for in Section 13.05, if applicable.

“ Opinion of Counsel ” means an opinion in writing signed by legal counsel for the Company (which counsel may be an employee of the Company), or outside counsel for the Company. Each such opinion shall include the statements provided for in Section 13.05, if applicable.

“ Original Issue Discount Debt Security ” means any Debt Security which provides for an amount less than the principal amount thereof to be due and payable upon a declaration or acceleration of the maturity thereof pursuant to Section 6.01.

“ Outstanding ” when used with respect to any series of Debt Securities, means, as of the date of determination, all Debt Securities of that series theretofore authenticated and delivered under this Indenture, except:

(i) Debt Securities of that series theretofore canceled by the Trustee or delivered to the Trustee for cancellation;

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(ii) Debt Securities of that series for whose payment or redemption money in the necessary amount has been theretofore deposited with the Trustee or any paying agent (other than the Company) in trust or set aside and segregated in trust by the Company (if the Company shall act as its own paying agent) for the holders of such Debt Securities; provided , that, if such Debt Securities are to be redeemed, notice of such redemption has been duly given pursuant to this Indenture or provision therefor satisfactory to the Trustee has been made; and

(iii) Debt Securities of that series which have been paid pursuant to Section 2.09 or in exchange for or in lieu of which other Debt Securities have been authenticated and delivered pursuant to this Indenture, other than any such Debt Securities in respect of which there shall have been presented to the Trustee proof satisfactory to it that such Debt Securities are held by a bona fide purchaser in whose hands such Debt Securities are valid obligations of the Company;

provided , however , that in determining whether the Holders of the requisite principal amount of the Outstanding Debt Securities of any series have given any request, demand, authorization, direction, notice, consent or waiver hereunder, Debt Securities owned by the Company or any other obligor upon the Debt Securities or any Affiliate of the Company or of such other obligor shall be disregarded and deemed not to be Outstanding, except that, in determining whether the Trustee shall be protected in relying upon any such request, demand, authorization, direction, notice, consent or waiver, only Debt Securities which the Trustee knows to be so owned shall be so disregarded. Debt Securities so owned which have been pledged in good faith may be regarded as Outstanding if the pledgee establishes to the satisfaction of the Trustee the pledgee’s right so to act with respect to such Debt Securities and that the pledgee is not the Company or any other obligor upon the Debt Securities or an Affiliate of the Company or of such other obligor.

In determining whether the Holders of the requisite principal amount of outstanding Debt Securities have given any request, demand, authorization, direction, notice, consent or waiver hereunder, the principal amount of an Original Issue Discount Debt Security that shall be deemed to be Outstanding for such purposes shall be the amount of the principal thereof that would be due and payable as of the date of such determination upon a declaration of acceleration of the maturity thereof pursuant to Section 6.01. In determining whether the Holders of the requisite principal amount of the Outstanding Debt Securities of any series have given any request, demand, authorization, direction, notice, consent or waiver hereunder, the principal amount of a Debt Security denominated in one or more Foreign Currencies that shall be deemed to be Outstanding for such purposes shall be the Dollar Equivalent, determined in the manner provided as contemplated by Section 2.03 on the date of original issuance of such Debt Security, of the principal amount (or, in the case of any Original Issue Discount Security, the Dollar Equivalent on the date of original issuance of such Debt Security of the amount determined as provided in the preceding sentence above) of such Debt Security.

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“ pari passu ”, as applied to the ranking of any Indebtedness of a Person in relation to other Indebtedness of such Person, means that each such Indebtedness either (i) is not subordinate in right of payment to any Indebtedness or (ii) is subordinate in right of payment to the same Indebtedness as is the other, and is so subordinate to the same extent, and is not subordinate in right of payment to each other or to any Indebtedness as to which the other is not so subordinate.

“ Person ” means any individual, corporation, partnership, joint venture, association, limited liability company, joint stock company, trust, unincorporated organization, government or any agency or political subdivision thereof or any other entity.

“ Place of Payment ” means, when used with respect to the Debt Securities of any series, the place or places where the principal of, and premium, if any, and interest on, the Debt Securities of that series are payable as specified pursuant to Section 2.03.

“ Preferred Stock ” as applied to the Capital Stock of any corporation, means Capital Stock of any class or classes (however designated) which is preferred as to the payment of dividends, or as to the distribution of assets upon any voluntary or involuntary liquidation or dissolution of such corporation, over shares of Capital Stock of any other class of such corporation.

“ Redeemable Stock ” means, with respect to any Person, any Capital Stock which by its terms (or by the terms of any security into which it is convertible or for which it is exchangeable) or upon the happening of any event (i) matures or is mandatorily redeemable pursuant to a sinking fund obligation or otherwise, (ii) is convertible or exchangeable for Indebtedness (other than Preferred Stock) or Disqualified Stock or (iii) is redeemable at the option of the holder thereof, in whole or in part.

“ Registered Holder ” means the Person in whose name a Registered Security is registered in the Debt Security Register (as defined in Section 2.07(a)).

“ Registered Security ” means any Debt Security registered as to principal and interest in the Debt Security Register (as defined in Section 2.07(a)).

“ Registrar ” has the meaning set forth in Section 2.07(a).

“ Representative ” means the trustee, agent or representative (if any) for an issue of Indebtedness.

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“ responsible officer ” means, when used with respect to the Trustee, any officer within the corporate trust office of the Trustee, including, the President, any Vice President, any Second Vice President, any Assistant Vice President, the Secretary, any senior trust officer, any trust officer or any other officer of the Trustee performing functions similar to those performed by the persons who at the time shall be such officers, and any other officer of the Trustee to whom corporate trust matters are referred because of his knowledge of and familiarity with the particular subject.

“ Secured Indebtedness ” means any Indebtedness of the Company secured by a Lien.

“ Securities Act ” means the Securities Act of 1933, as amended.

“ Senior Indebtedness ” means, as to any series of Debt Securities subordinated pursuant to the provisions of Article 12, the Indebtedness of the Company identified as Senior Indebtedness in the resolution of the Board of Directors and accompanying Officers’ Certificate or supplemental Indenture setting forth the terms, including as to subordination, of such series.

“ Senior Subordinated Indebtedness ” means the Debt Securities and any other Indebtedness of the Company that specifically provides that such Indebtedness is to rank equally with the Debt Securities in right of payment and is not subordinated by its terms in right of payment to any Indebtedness or other obligation of the Company which is not Senior Indebtedness.

“ Stated Maturity ” means, with respect to any security, the date specified in such security as the fixed date on which the payment of principal of such security is due and payable, including pursuant to any mandatory redemption provision (but excluding any provision providing for the repurchase of such security at the option of the holder thereof upon the happening of any contingency beyond the control of the issuer unless such contingency has occurred).

“ Subsidiary ” of any Person means any corporation, association, partnership or other business entity of which more than 50% of the total voting power of shares of Capital Stock entitled (without regard to the occurrence of any contingency) to vote in the election of directors, managers or trustees thereof is at the time owned or controlled, directly or indirectly, by (i) such Person, (ii) such Person and one or more Subsidiaries of such Person or (iii) one or more Subsidiaries of such Person.

“ Significant Subsidiary ” of any Person means any Subsidiary that accounts for (a) 10% or more of the total consolidated assets of the Company and its Subsidiaries as of any date of determination, or (b) 10% or more of the total consolidated revenues of the Company and its Subsidiaries for the Company’s most recently concluded fiscal quarter.

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“ Temporary Cash Investments ” means any of the following: (i) investments in U.S. Government Obligations maturing within 90 days of the date of acquisition thereof, (ii) investments in time deposit accounts, certificates of deposit and money market deposits maturing within 90 days of the date of acquisition thereof issued by a bank or trust company which is organized under the laws of the United States, any State thereof or any foreign country recognized by the United States having capital, surplus and undivided profits aggregating in excess of $500,000,000 (or the Dollar Equivalent thereof) and whose long-term debt is rated “A” or higher according to Moody’s Investors Service, Inc. (or such similar equivalent rating by at least one “nationally recognized statistical rating organization” (as defined in Rule 436 under the Securities Act)), (iii) repurchase obligations with a term of not more than 7 days for underlying securities of the types described in clause (i) above entered into with a bank meeting the qualifications described in clause (ii) above and (iv) investments in commercial paper, maturing not more than 90 days after the date of acquisition, issued by a corporation (other than an Affiliate of the Company) organized and in existence under the laws of the United States or any foreign country recognized by the United States with a rating at the time as of which any investment therein is made of “P-1” (or higher) according to Moody’s Investors Service, Inc. or “A-1” (or higher) according to Standard and Poor’s Corporation.

“ Trade Payables ” means, with respect to any Person, any accounts payable or any Indebtedness or monetary obligation to trade creditors created, assumed or Guaranteed by such Person arising in the ordinary course of business of such Person in connection with the acquisition of goods or services.

“ Trustee ” initially means Wilmington Trust FSB and any other Person or Persons appointed as such from time to time pursuant to Section 7.08, and, subject to the provisions of Article 7, includes its or their successors and assigns. If at any time there is more than one such Person, “Trustee” as used with respect to the Debt Securities of any series shall mean the Trustee with respect to the Debt Securities of that series.

“ Trust Indenture Act ” (except as herein otherwise expressly provided) means the Trust Indenture Act of 1939 as in force at the date of this indenture as originally executed and, to the extent required by law, as amended.

“ United States ” means the United States of America (including the States and the District of Columbia), its territories, its possessions and other areas subject to its jurisdiction.

“ U.S. Government Obligations ” means securities that are (x) direct obligations of the United States for the payment of which its full faith and credit is pledged or (y) obligations of a Person controlled or supervised by and acting as an agency or instrumentality of the United States, the payment of which is unconditionally guaranteed as a full faith and credit obligation by the United States, which, in either case, are not callable or redeemable at the option of the issuer thereof.

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“ Yield to Maturity ” means the yield to maturity calculated at the time of issuance of a series of Debt Securities, or, if applicable, at the most recent redetermination of interest on such series and calculated in accordance with accepted financial practice.

Section 1.02 . Incorporation by Reference of Trust Indenture Act. This Indenture is subject to the mandatory provisions of the Trust Indenture Act which are incorporated by reference in and made a part of this indenture. The following Trust Indenture Act terms have the following meanings:

“ indenture securities ” means the Debt Securities.

“ indenture security holder ” means a Holder.

“ indenture to be qualified ” means this Indenture.

“ indenture trustee ” or “ institutional trustee ” means the Trustee.

“ obligor ” on the indenture securities means the Company and any other obligor on the Debt Securities.

All other Trust Indenture Act terms used in this Indenture that are defined by the Trust indenture Act, reference to another statute or defined by rules of the Securities and Exchange Commission have the meanings assigned to them by such definitions.

Section 1.03 . Rules of Construction. Unless the context otherwise requires:

(a) a term has the meaning assigned to it;

(b) an accounting term not otherwise defined has the meaning assigned to it in accordance with GAAP;

(c) “or” is not exclusive;

(d) “including” means including without limitation;

(e) words in the singular include the plural and words in the plural include the singular;

(f) if the applicable series of Debt Securities are subordinated pursuant to Article 12, unsecured indebtedness shall not be deemed to be subordinate or junior to Secured Indebtedness merely by virtue of its nature as unsecured indebtedness;

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(g) except as otherwise provided in the definition of “Outstanding” contained in Section 1.01 hereunder, the principal amount of any noninterest bearing or other discount security at any date shall be the principal amount thereof that would be shown on a balance sheet of the issuer dated such date prepared in accordance with GAAP; and

(h) the principal amount of any Preferred Stock shall be the greater of (i) the maximum liquidation value of such Preferred Stock or (ii) the maximum mandatory redemption or mandatory repurchase price with respect to such Preferred Stock.

ARTICLE 2

D EBT S ECURITIES

Section 2.01 . Forms Generally. The Debt Securities of each series shall be in substantially the form established without the approval of any Holder by or pursuant to a resolution of the Board of Directors or in one or more Indentures supplemental hereto, in each case with such appropriate insertions, omissions, substitutions and other variations as are required or permitted by this Indenture, and may have such letters, numbers or other marks of identification or designation and such legends or endorsements placed thereon as the Company may deem appropriate and as are not inconsistent with the provisions of this Indenture, or as may be required or appropriate to comply with any law or with any rules made pursuant thereto or with any rules of any securities exchange on which such series of Debt Securities may be listed, or to conform to general usage, or as may, consistently herewith, be determined by the officers executing such Debt Securities as evidenced by their execution of the Debt Securities.

The definitive Debt Securities of each series shall be printed, lithographed or engraved on steel engraved borders or may be produced in any other manner, all as determined by the officers executing such Debt Securities, as evidenced by their execution of such Debt Securities.

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Section 2.02 . Form of Trustee’s Certificate of Authentication. The Trustee’s Certificate of Authentication on all Debt Securities authenticated by the Trustee shall be in substantially the following form:

TRUSTEE’S CERTIFICATE OF AUTHENTICATION

This is one of the Debt Securities of the series designated therein referred to in the within-mentioned Indenture.

Section 2.03 . Principal Amount; Issuable in Series. The aggregate principal amount of Debt Securities which may be issued, executed, authenticated, delivered and outstanding under this Indenture is unlimited.

The Debt Securities may be issued in one or more series. There shall be established, without the approval of any Holders, in or pursuant to a resolution of the Board of Directors and set forth in an Officers’ Certificate, or established in one or more Indentures supplemental hereto, prior to the issuance of Debt Securities of any series any or all of the following:

(a) the title of the Debt Securities of the series (which shall distinguish the Debt Securities of the series from all other Debt Securities);

(b) any limit upon the aggregate principal amount of the Debt Securities of the series which may be authenticated and delivered under this Indenture (except for Debt Securities authenticated and delivered upon registration of transfer of, or in exchange for, or in lieu of, other Debt Securities of the series pursuant to this Article 2);

(c) the date or dates on which the principal and premium, if any, of the Debt Securities of the series are payable;

(d) the rate or rates (which may be fixed or variable) at which the Debt Securities of the series shall bear interest, if any, or the method of determining such rate or rates, the date or dates from which such interest shall accrue, the interest payment dates on which such interest shall be payable, or the method by which such date will be determined, in the case of Registered Securities, the record dates for the determination of Holders thereof to whom such interest is payable; and the basis upon which interest will be calculated if other than that of a 360-day year of twelve thirty-day months;

(e) the Place or Places of Payment, if any, in addition to or instead of the corporate trust office of the Trustee where the principal of, and interest on, Debt Securities of the series shall be payable;

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(f) the price or prices at which, the period or periods within which and the terms and conditions upon which Debt Securities of the series may be redeemed, in whole or in part, at the option of the Company or otherwise;

(g) the obligation, if any, of the Company to redeem, purchase or repay Debt Securities of the series pursuant to any sinking fund or analogous provisions or at the option of a Holder thereof, and the price or prices at which and the period or periods within which and the terms and conditions upon which Debt Securities of the series shall be redeemed, purchased or repaid, in whole or in part, pursuant to such obligations;

(h) the terms, if any, upon which the Debt Securities of the series may be convertible into or exchanged for Common Stock, Preferred Stock (which may be represented by depositary shares), other Debt Securities or warrants for Common Stock, Preferred Stock or Indebtedness or other securities of any kind of the Company or any other obligor or issuer and the terms and conditions upon which such conversion or exchange shall be effected, including the initial conversion or exchange price or rate, the conversion or exchange period and any other provision in addition to or in lieu of those described herein;

(i) if other than denominations of $1,000 and any integral multiple thereof, the denominations in which Debt Securities of the series shall be issuable;

(j) if the amount of principal of or any premium or interest on Debt Securities of the series may be determined with reference to an index or pursuant to a formula, the manner in which such amounts will be determined;

(k) if the principal amount payable at the Stated Maturity of Debt Securities of the series will not be determinable as of any one or more dates prior to such Stated Maturity, the amount which will be deemed to be such principal amount as of any such date for any purpose, including the principal amount thereof which will be due and payable upon any maturity other than the Stated Maturity or which will be deemed to be Outstanding as of any such date (or, in any such case, the manner in which such deemed principal amount is to be determined); and the manner of determining the equivalent thereof in the currency of the United States of America for purposes of the definition of Dollar Equivalent;

(l) any changes or additions to Article 11, including the addition of additional covenants that may be subject to the covenant defeasance option pursuant to Section 11.03;

(m) if other than such coin or Currency of the United States as at the time of payment is legal tender for payment of public and private debts, the coin or Currency or Currencies or units of two or more Currencies in which payment of the principal of and premium, if any, and interest on, Debt Securities of the series shall be payable;

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(n) if other than the principal amount thereof, the portion of the principal amount of Debt Securities of the series which shall be payable upon declaration of acceleration of the maturity thereof pursuant to Section 6.01 or provable in bankruptcy pursuant to Section 6.02;

(o) the terms, if any, of the transfer, mortgage, pledge or assignment as security for the Debt Securities of the series of any properties, assets, moneys, proceeds, securities or other collateral, including whether certain provisions of the Trust Indenture Act are applicable and any corresponding changes to provisions of this Indenture as currently in effect;

(p) any addition to or change in the Events of Default with respect to the Debt Securities of the series and any change in the right of the Trustee or the Holders to declare the principal of and interest on, such Debt Securities due and payable;

(q) if the Debt Securities of the series shall be issued in whole or in part in the form of a Global Security or Securities, the terms and conditions, if any, in addition to or in lieu of the terms and conditions set forth in Section 2.15(c), upon which such Global Security or Securities may be exchanged in whole or in part for other individual Debt Securities in definitive registered form; and the Depositary for such Global Security or Securities and the form of any legend or legends to be borne by any such Global Security or Securities in addition to or in lieu of the legend referred to in Section 2.15;

(r) any trustees, authenticating or paying agents, transfer agents or registrars;

(s) the applicability of, and any addition to or change in the covenants and definitions currently set forth in this Indenture or in the terms currently set forth in Article 10, including conditioning any merger, conveyance, transfer or lease permitted by Article 10 upon the satisfaction of an Indebtedness coverage standard by the Company and Successor Company (as defined in Article 10);

(t) the terms, if any, of any Guarantee of the payment of principal of, and premium, if any, and interest on, Debt Securities of the series and any corresponding changes to the provisions of this Indenture as currently in effect;

(u) the subordination, if any, of the Debt Securities of the series pursuant to Article 12 and any changes or additions to Article 12 with respect to such Debt Securities;

(v) with regard to Debt Securities of the series that do not bear interest, the dates for certain required reports to the Trustee;

(w) any material United States federal income tax consequences or other special considerations applicable to the Debt Securities of the series; and

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(x) any other terms of the Debt Securities of the series (which terms shall not be prohibited by the provisions of this Indenture).

All Debt Securities of any one series appertaining thereto shall be substantially identical except as to denomination and except as may otherwise be provided in or pursuant to such resolution of the Board of Directors and as set forth in such Officers’ Certificate or in any such Indenture supplemental hereto.

Unless otherwise expressly provided with respect to a series of Debt Securities, the aggregate principal amount of a series of Debt Securities may be increased by or pursuant to a resolution of the Board of Directors and additional Debt Securities of such series may be issued up to the increased maximum aggregate principal amount so authorized.

Section 2.04 . Execution of Debt Securities. The Debt Securities shall be signed on behalf of the Company by its Chairman of the Board, its Vice Chairman, its President or a Vice President and by its Secretary, an Assistant Secretary, a Treasurer or an Assistant Treasurer. Such signatures upon the Debt Securities may be the manual or facsimile signatures of the present or any future such authorized officers and may be imprinted or otherwise reproduced on the Debt Securities. The seal of the Company, if any, may be in the form of a facsimile thereof and may be impressed, affixed, imprinted or otherwise reproduced on the Debt Securities.

Only such Debt Securities as shall bear thereon a certificate of authentication substantially in the form hereinbefore recited, signed manually by an authorized officer of the Trustee, shall be entitled to the benefits of this Indenture or be valid or obligatory for any purpose. Such certificate by the Trustee upon any Debt Security executed by the Company shall be conclusive evidence that the Debt Security so authenticated has been duly authenticated and delivered hereunder.

In case any officer of the Company who shall have signed any of the Debt Securities shall cease to be such officer before the Debt Securities so signed shall have been authenticated and delivered by the Trustee, or disposed of by the Company, such Debt Securities nevertheless may be authenticated and delivered or disposed of as though the Person who signed such Debt Securities had not ceased to be such officer of the Company; and any Debt Security may be signed on behalf of the Company by such Persons as, at the actual date of the execution of such Debt Security, shall be the proper officers of the Company, although at the date of such Debt Security or of the execution of this Indenture any such Person was not such officer.

Section 2.05 . Authentication and Delivery of Debt Securities. At any time and from time to time after the execution and delivery of this Indenture, the Company may deliver Debt Securities of any series executed by the Company to the Trustee for authentication, and the Trustee shall thereupon authenticate and

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deliver said Debt Securities pursuant to a Company Order. In authenticating such Debt Securities and accepting the additional responsibilities under this Indenture in relation to such Debt Securities, the Trustee shall be entitled to receive, and (subject to Section 7.01.) shall be fully protected in relying upon:

(a) a copy of any resolution or resolutions of the Board of Directors, certified by the Secretary or Assistant Secretary of the Company, authorizing the terms of issuance of the series of Debt Securities;

(b) an executed supplemental Indenture, if any;

(c) an Officers’ Certificate prepared pursuant to Section 13.05 and, if applicable, pursuant to Sections 2.03 and 9.03; and

(d) an opinion of Counsel prepared in accordance with Section 13.05 which shall also state:

(i) that the form of such Debt Securities has been established by or pursuant to a resolution of the Board of Directors or by a supplemental Indenture as permitted by Section 2.01 in conformity with the provisions of this Indenture;

(ii) that the terms of such Debt Securities have been established by or pursuant to a resolution of the Board of Directors or by a supplemental Indenture as permitted by Section 2.03 in conformity with the provisions of this Indenture, and, in the case of the issuance of Debt Securities pursuant to Section 2.16, the terms of such Debt Securities that have been established by or pursuant to a resolution of the Board of Directors or by a supplemental Indenture have been established as permitted by Section 2.03 in conformity with the provisions of the Indenture and, when such other terms as are to be established pursuant to procedures set forth in a Company Order or pursuant to such other procedures as shall have been provided for with respect to such Debt Securities shall have been established, all such terms will have been established in conformity with the provisions of this Indenture;

(iii) that such Debt Securities, when authenticated and delivered by the Trustee and issued by the Company in the manner and subject to any conditions specified in such opinion of Counsel, will constitute valid and legally binding obligations of the Company, enforceable in accordance with their terms except as the enforceability thereof may be limited by (i) bankruptcy, insolvency, reorganization or similar laws affecting the enforcement of creditors’ rights generally and (ii) general principles of equity, whether such principles are considered in a proceeding at law or in equity;

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(iv) that the Company has the corporate power to issue such Debt Securities and has duly taken all necessary corporate action with respect to such issuance;

(v) that the issuance of such Debt Securities will not contravene the charter or by-laws of the Company or result in any material violation of any of the terms or provisions of any law or regulation or of any indenture, mortgage or other agreement known to such counsel by which the Company is bound;

(vi) that authentication and delivery of such Debt Securities and the execution and delivery of any supplemental Indenture will not violate the terms of this Indenture; and

(vii) such other matters as the Trustee may reasonably request.

Such Opinion of Counsel need express no opinion as to whether a court in the United States would render a money judgment in a currency other than that of the United States.

The Trustee shall have the right to decline to authenticate and deliver any Debt Securities under this Section 2.05 if the Trustee, being advised by counsel, determines that such action may not lawfully be taken or if the Trustee in good faith by its board of directors or trustees, executive committee or a trust committee of directors or trustees and/or vice presidents shall determine that such action would expose the Trustee to personal liability to existing Holders or would adversely affect the Trustee’s rights, duties, obligations or immunities under this Indenture in a manner which is not reasonably acceptable to the Trustee.

The Trustee may appoint an authenticating agent reasonably acceptable to the Company to authenticate Debt Securities of any series. Unless limited by the terms of such appointment, an authenticating agent may authenticate Debt Securities whenever the Trustee may do so. Each reference in this Indenture to authentication by the Trustee includes authentication by such agent. An authenticating agent has the same rights as any Registrar, paying agent or agent for service of notices and demands.

Unless otherwise provided in the form of Debt Security for any series, each Debt Security shall be dated the date of its authentication.

Section 2.06 . Denomination of Debt Securities. Unless otherwise provided in the form of Debt Security for any series, the Debt Securities of each series shall be issuable only as Registered Securities in such denominations as shall be specified or contemplated by Section 2.03. In the absence of any such specification with respect to the Debt Securities of any series, the Debt Securities of such series shall be issuable in denominations of $1,000 and any integral multiple thereof.

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Section 2.07 . Registration of Transfer and Exchange.

(a) The Company shall keep or cause to be kept a register for each series of Registered Securities issued hereunder (hereinafter collectively referred to as the “ Debt Security Register ”), in which, subject to such reasonable regulations as it may prescribe, the Company shall provide for the registration of Registered Securities and the registration of transfer or exchange of Registered Securities as in this Article 2 provided. At all reasonable times the Debt Security Register shall be open for inspection by the Trustee. Subject to Section 2.15, upon due presentment for registration of transfer of any Registered Security at any office or agency to be maintained by the Company in accordance with the provisions of Section 4.02, the Company shall execute and the Trustee shall authenticate and deliver in the name of the transferee or transferees a new Registered Security or Registered Securities of the same series, for a like aggregate principal amount and tenor, in authorized denominations.

Unless and until otherwise determined by the Company by resolution of the Board of Directors, the register of the Company for the purpose of registration, exchange or registration of transfer of the Registered Securities shall be kept at the corporate trust office of the Trustee and, for this purpose, the Trustee shall be designated “ Registrar ”.

Registered Securities of any series (other than a Global Security) may be exchanged for a like aggregate principal amount and tenor of Registered Securities of the same series of other authorized denominations. Subject to Section 2.15, Registered Securities to be exchanged shall be surrendered at the office or agency to be maintained by the Company as provided in Section 4.02, and the Company shall execute and the Trustee shall authenticate and deliver in exchange therefor the Registered Security or Registered Securities which the Holder making the exchange shall be entitled to receive.

(b) All Registered Securities presented or surrendered for registration of transfer, exchange or payment shall (if so required by the Company, the Trustee or the Registrar) be duly endorsed or be accompanied by a written instrument or instruments of transfer, in form satisfactory to the Company, the Trustee and the Registrar, duly executed by the Registered Holder or his attorney duly authorized in writing.

All Debt Securities issued in exchange for or upon transfer of Debt Securities shall be the valid obligations of the Company, evidencing the same debt, and entitled to the same benefits under this Indenture as the Debt Securities surrendered for such exchange or transfer. No service charge shall be made for any exchange or registration of transfer of Debt Securities (except as provided by Section 2.09), but the Company may require payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in relation thereto, other than those expressly provided in this Indenture to be made at the Company’s own expense or without expense or without charge to the Holders.

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The Company shall not be required (a) to issue, register the transfer of or exchange any Debt Securities for a period of 15 days next preceding any mailing of notice of redemption of Debt Securities of such series or (b) to register the transfer of or exchange any Debt Securities selected, called or being called for redemption in whole or in part, except, in the case of Debt Securities to be redeemed in part, the portion thereof not to be so redeemed.

Prior to the due presentation for registration of transfer of any Debt Security, the Company, the Trustee, any paying agent or any Registrar may deem and treat the Person in whose name a Debt Security is registered as the absolute owner of such Debt Security for the purpose of receiving payment of principal of, and premium, if any, and (subject to Section 2.12(a)) interest on, such Debt Security and for all other purposes whatsoever, whether or not such Debt Security is overdue, and none of the Company, the Trustee, any paying agent or Registrar shall be affected by notice to the contrary.

None of the Company, the Trustee, any agent of the Trustee, any paying agent or any Registrar will have any responsibility or liability for any aspect of the records relating to, or payments made on account of, beneficial ownership interests of a Global Security or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

Section 2.08 . Temporary Debt Securities. Pending the preparation of definitive Debt Securities of any series, the Company may execute and the Trustee shall authenticate and deliver temporary Debt Securities (printed, lithographed, photocopied, typewritten or otherwise produced) of any authorized denomination, and substantially in the form of the definitive Debt Securities in lieu of which they are issued, in registered form and with such omissions, insertions and variations as may be appropriate for temporary Debt Securities, all as may be determined by the Company with the concurrence of the Trustee. Temporary Debt Securities may contain such reference to any provisions of this Indenture as may be appropriate. Every temporary Debt Security shall be executed by the Company and be authenticated by the Trustee upon the same conditions and in substantially the same manner, and with like effect, as the definitive Debt Securities.

If temporary Debt Securities of any series are issued, the Company will cause definitive Debt Securities of such series to be prepared without unreasonable delay. After the preparation of definitive Debt Securities of such series, the temporary Debt Securities of such series shall be exchangeable for definitive Debt Securities of such series upon surrender of the temporary Debt Securities of such series at the office or agency of the Company at a Place of Payment for such series, without charge to the Holder thereof, except as provided in Section 2.07 in connection with a transfer, and upon surrender for cancellation of any one or more temporary Debt Securities of any series, the Company shall execute and the Trustee shall authenticate and deliver in exchange therefor a like principal amount of definitive Debt Securities of the same series of authorized

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denominations and of like tenor. Until so exchanged, temporary Debt Securities of any series shall in all respects be entitled to the same benefits under this Indenture as definitive Debt Securities of such series, except as otherwise specified as contemplated by Section 2.03(q) with respect to the payment of interest on Global Securities in temporary form.

Upon any exchange of a portion of a temporary Global Security for a definitive Global Security or for the individual Debt Securities represented thereby pursuant to Section 2.07 or this Section 2.08, the temporary Global Security shall be endorsed by the Trustee to reflect the reduction of the principal amount evidenced thereby, whereupon the principal amount of such temporary Global Security shall be reduced for all purposes by the amount so exchanged and endorsed.

Section 2.09 . Mutilated, Destroyed, Lost or Stolen Debt Securities. If (i) any mutilated Debt Security is surrendered to the Trustee at its corporate trust office or (ii) the Company and the Trustee receive evidence to their satisfaction of the destruction, loss or theft of any Debt Security, and there is delivered to the Company and the Trustee such security or indemnity as may be required by them to save each of them and any paying agent harmless, and neither the Company nor the Trustee receives notice that such Debt Security has been acquired by a bona fide purchaser, then the Company shall execute and, upon a Company Order, the Trustee shall authenticate and deliver, in exchange for or in lieu of any such mutilated, destroyed, lost or stolen Debt Security, a new Debt Security of the same series of like tenor, form, terms and principal amount, bearing a number not contemporaneously Outstanding. Upon the issuance of any substituted Debt Security, the Company may require the payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in relation thereto and any other expenses connected therewith. In case any Debt Security which has matured or is about to mature or which has been called for redemption shall become mutilated or be destroyed, lost or stolen, the Company may, instead of issuing a substituted Debt Security, pay or authorize the payment of the same (without surrender thereof except in the case of a mutilated Debt Security) if the applicant for such payment shall furnish the Company and the Trustee with such security or indemnity as either may require to save it harmless from all risk, however remote, and, in case of destruction, loss or theft, evidence to the satisfaction of the Company and the Trustee of the destruction, loss or theft of such Debt Security and of the ownership thereof.

Every substituted Debt Security of any series issued pursuant to the provisions of this Section 2.09 by virtue of the fact that any Debt Security is destroyed, lost or stolen shall constitute an original additional contractual obligation of the Company, whether or not the destroyed, lost or stolen Debt Security shall be found at any time, and shall be entitled to all the benefits of this Indenture equally and proportionately with any and all other Debt Securities of that series duly issued hereunder. All Debt Securities shall be held and owned upon the express condition that the foregoing provisions are exclusive with

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respect to the replacement or payment of mutilated, destroyed, lost or stolen Debt Securities, and shall preclude any and all other rights or remedies, notwithstanding any law or statute existing or hereafter enacted to the contrary with respect to the replacement or payment of negotiable instruments or other securities without their surrender.

Section 2.10 . Cancellation of Surrendered Debt Securities. All Debt Securities surrendered for payment, redemption, registration of transfer or exchange shall, if surrendered to the Company or any paying agent or a Registrar, be delivered to the Trustee for cancellation by it, or if surrendered to the Trustee, shall be canceled by it, and no Debt Securities shall be issued in lieu thereof except as expressly permitted by any of the provisions of this Indenture. All canceled Debt Securities held by the Trustee shall be disposed of by the Trustee in accordance with its customary procedures, and certification by the Trustee of their cancellation shall be delivered to the Company at its written request. If the Company shall acquire any of the Debt Securities, however, such acquisition shall not operate as a redemption or satisfaction of the indebtedness represented thereby unless and until the same are delivered or surrendered to the Trustee for cancellation. The Company may not issue new Debt Securities to replace Debt Securities it has redeemed, paid or delivered to the Trustee for cancellation.

Section 2.11 . Provisions of the Indenture and Debt Securities for the Sole Benefit of the Parties and the Holders. Nothing in this Indenture or in the Debt Securities, expressed or implied, shall give or be construed to give to any Person, other than the parties hereto, the Holders or any Registrar or paying agent or the holders of Senior Indebtedness, if any, any legal or equitable right, remedy or claim under or in respect of this Indenture, or under any covenant, condition or provision herein contained; all its covenants, conditions and provisions being for the sole benefit of the parties hereto, the Holders and any Registrar and paying agents and the holders of Senior Indebtedness, if any.

Section 2.12 . Payment of Interest; Rights Preserved.

(a) Interest on any Registered Security that is payable and is punctually paid or duly provided for on any interest payment date shall be paid to the Person in whose name such Registered Security is registered at the close of business on the regular record date for such interest notwithstanding the cancellation of such Registered Security upon any transfer or exchange subsequent to the regular record date. Payment of interest on Registered Securities shall be made at the corporate trust office of the Trustee (except as otherwise specified pursuant to Section 2.03), or at the option of the Company, by check mailed to the address of the Person entitled thereto as such address shall appear in the Debt Security Register or, if provided pursuant to Section 2.03 and in accordance with arrangements satisfactory to the Trustee, at the option of the Registered Holder by wire transfer to an account designated by the Registered Holder.

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(b) Subject to the foregoing provisions of this Section 2.12 and Section 2.17, each Debt Security of a particular series delivered under this Indenture upon registration of transfer of or in exchange for or in lieu of any other Debt Security of the same series shall carry the rights to interest accrued and unpaid, and to accrue, which were carried by such other Debt Security.

Section 2.13 . Securities Denominated In Foreign Currencies.

(a) Except as otherwise specified pursuant to Section 2.03 for Registered Securities of any series, payment of the principal of, and premium, if any, and interest on, Registered Securities of such series will be made in Dollars.

(b) For the purposes of calculating the principal amount of Debt Securities of any series denominated in a Foreign Currency or in units of two or more Foreign Currencies for any purpose under this Indenture, the principal amount of such Debt Securities at any time Outstanding shall be deemed to be the Dollar Equivalent of such principal amount as of the date of any such calculation.

In the event any Foreign Currency or currencies or units of two or more Currencies in which any payment with respect to any series of Debt Securities may be made ceases to be a freely convertible Currency on United States Currency markets, for any date thereafter on which payment of principal of, or premium, if any, or interest on, the Debt Securities of a series is due, the Company shall select the Currency of payment for use on such date, all as provided in the Debt Securities of such series. In such event, the Company shall, as provided in the Debt Securities of such series, notify the Trustee of the Currency which it has selected to constitute the funds necessary to meet the Company’s obligations on such payment date and of the amount of such Currency to be paid. Such amount shall be determined as provided in the Debt Securities of such series. The payment to the Trustee with respect to such payment date shall be made by the Company solely in the Currency so selected.

Section 2.14 . Wire Transfers. Notwithstanding any other provision to the contrary in this Indenture, the Company may make any payment of monies required to be deposited with the Trustee on account of principal of, or premium, if any, or interest on, the Debt Securities (whether pursuant to optional or mandatory redemption payments, interest payments or otherwise) by wire transfer of immediately available funds to an account designated by the Trustee on or before 10:00 a.m. (New York City Time) on the date such moneys are to be paid to the Holders of the Debt Securities in accordance with the terms hereof.

Section 2.15 . Securities Issuable in the Form of a Global Security.

(a) If the Company shall establish pursuant to Sections 2.01 and 2.03 that the Debt Securities of a particular series are to be issued in whole or in part in the form of one or more Global Securities, then the Company shall execute and the Trustee or its agent shall, in accordance with Section 2.05, authenticate and

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deliver, such Global Security or Securities, which (i) shall represent, and shall be denominated in an amount equal to the aggregate principal amount of, the Outstanding Debt Securities of such series to be represented by such Global Security or Securities, or such portion thereof as the Company shall specify in an Officers’ Certificate or Company Order, (ii) shall be registered in the name of the Depositary or its nominee for such Global Security or securities or its nominee, (iii) shall be delivered by the Trustee or its agent to the Depositary or pursuant to the Depositary’s instruction or held by the Trustee as custodian for the Depositary and (iv) shall bear a legend substantially to the following effect: “Unless and until it is exchanged in whole or in part for the individual Debt Securities represented hereby, this Global Security may not be transferred except as a whole by the Depositary to a nominee of the Depositary or by a nominee of the Depositary to the Depositary or another nominee of the Depositary or by the Depositary or any such nominee to a successor Depositary or a nominee of such successor Depositary”, or such other legend as may then be required by the Depositary for such Global Security or Securities.

(b) Notwithstanding any other provision of this Section 2.15 or of Section 2.07 to the contrary, and subject to the provisions of paragraph (c) below, unless the terms of a Global Security expressly permit such Global Security to be exchanged in whole or in part for definitive Debt Securities in registered form, a Global Security may be transferred, in whole but not in part and in the manner provided in Section 2.07, only by the Depositary to a nominee of the Depositary for such Global Security, or by a nominee of the Depositary to the Depositary or another nominee of the Depositary, or by the Depositary or a nominee of the Depositary to a successor Depositary for such Global Security selected or approved by the Company, or to a nominee of such successor Depositary.

(c)(i) If at any time the Depositary for a Global Security or Securities notifies the Company that it is unwilling or unable to continue as Depositary for such Global Security or Securities or if at any time the Depositary for the Debt Securities for such series shall no longer be eligible or in good standing under the Exchange Act or other applicable statute, rule or regulation, the Company shall appoint a successor Depositary with respect to such Global Security or Securities. If a successor Depositary for such Global Security or Securities is not appointed by the Company within 90 days after the Company receives such notice or becomes aware of such ineligibility, the Company shall execute, and the Trustee or its agent, upon receipt of a Company Order for the authentication and delivery of such individual Debt Securities of such series in exchange for such Global Security, will authenticate and deliver, individual Debt Securities of such series of like tenor and terms in definitive form in an aggregate principal amount equal to the principal amount of the Global Security in exchange for such Global Security or Securities.

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(ii) The Company may at any time and in its sole discretion determine that the Debt Securities of any series or portion thereof issued or issuable in the form of one or more Global Securities shall no longer be represented by such Global Security or Securities. In such event the Company will execute, and the Trustee, upon receipt of a Company Order for the authentication and delivery of individual Debt Securities of such series in exchange in whole or in part for such Global Security, will authenticate and deliver individual Debt Securities of such series of like tenor and terms in definitive form in an aggregate principal amount equal to the principal amount of such series or portion thereof in exchange for such Global Security or Securities.

(iii) If specified by the Company pursuant to Sections 2.01 and 2.03 with respect to Debt Securities issued or issuable in the form of a Global Security, the Depositary for such Global Security may surrender such Global Security in exchange in whole or in part for individual Debt Securities of such series of like tenor and terms in definitive form on such terms as are acceptable to the Company, the Trustee and such Depositary. Thereupon the Company shall execute, and the Trustee or its agent upon receipt of a Company Order for the authentication and delivery of definitive Debt Securities of such series shall authenticate and deliver, without service charge, (1) to each Person specified by such Depositary a new Debt Security or Securities of the same series of like tenor and terms and of any authorized denomination as requested by such Person in aggregate principal amount equal to and in exchange for such Person’s beneficial interest in the Global Security; and (2) to such Depositary a new Global Security of like tenor and terms and in an authorized denomination equal to the difference, if any, between the principal amount of the surrendered Global Security and the aggregate principal amount of Debt Securities delivered to Holders thereof.

(iv) In any exchange provided for in any of the preceding three paragraphs, the Company will execute and the Trustee or its agent will authenticate and deliver individual Debt Securities. Upon the exchange of the entire principal amount of a Global Security for individual Debt Securities, such Global Security shall be canceled by the Trustee or its agent. Except as provided in the preceding paragraph, Registered Securities issued in exchange for a Global Security pursuant to this Section 2.15 shall be registered in such names and in such authorized denominations as the Depositary for such Global Security, pursuant to instructions from its direct or indirect participants or otherwise, shall instruct the Trustee or the Registrar. The Trustee or the Registrar shall deliver such Registered Securities to the Persons in whose names such Registered Securities are so registered.

(v) Payments in respect of the principal of and interest on any Debt Securities registered in the name of the Depositary or its nominee will be payable to the Depositary or such nominee in its capacity as the registered owner of such Global Security. The Company and the Trustee may treat the Person in whose name the Debt Securities, including the

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Global Security, are registered as the owner thereof for the purpose of receiving such payments and for any and all other purposes whatsoever. None of the Company, the Trustee, any Registrar, the paying agent or any agent of the Company or the Trustee will have any responsibility or liability for (a) any aspect of the records relating to or payments made on account of the beneficial ownership interests of the Global Security by the Depositary or its nominee or any of the Depositary’s direct or indirect participants, or for maintaining, supervising or reviewing any records of the Depositary, its nominee or any of its direct or indirect participants relating to the beneficial ownership interests of the Global Security, (b) the payments to the beneficial owners of the Global Security of amounts paid to the Depositary or its nominee, or (c) any other matter relating to the actions and practices of the Depositary, its nominee or any of its direct or indirect participants. None of the Company, the Trustee or any such agent will be liable for any delay by the Depositary, its nominee, or any of its direct or indirect participants in identifying the beneficial owners of the Debt Securities, and the Company and the Trustee may conclusively rely on, and will be protected in relying on, instructions from the Depositary or its nominee for all purposes (including with respect to the registration and delivery, and the respective principal amounts, of the Debt Securities to be issued).

Section 2.16 . Medium Term Securities. Notwithstanding any contrary provision herein, if all Debt Securities of a series are not to be originally issued at one time, it shall not be necessary for the Company to deliver to the Trustee an Officers’ Certificate, resolutions of the Board of Directors, supplemental Indenture, Opinion of Counsel or written order or any other document otherwise required pursuant to Section 2.01, 2.03, 2.05 or 13.05 at or prior to the time of authentication of each Debt Security of such series if such documents are delivered to the Trustee or its agent at or prior to the authentication upon original issuance of the first such Debt Security of such series to be issued; provided , that any subsequent request by the Company to the Trustee to authenticate Debt Securities of such series upon original issuance shall constitute a representation and warranty by the Company that, as of the date of such request, the statements made in the Officers’ Certificate delivered pursuant to Section 2.05 or 13.05 shall be true and correct as if made on such date and that the Opinion of Counsel delivered at or prior to such time of authentication upon original issuance of Debt Securities shall specifically state that it shall relate to all subsequent issuances of Debt Securities of such series that are identical to the Debt Securities issued in the first issuance of Debt Securities of such series.

A Company Order delivered by the Company to the Trustee in the circumstances set forth in the preceding paragraph, may provide that Debt Securities which are the subject thereof will be authenticated and delivered by the Trustee or its agent on original issue from time to time upon the written order of Persons designated in such written order and that such Persons are authorized to

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determine, consistent with the Officers’ Certificate, supplemental Indenture or resolution of the Board of Directors relating to such written order, such terms and conditions of such Debt Securities as are specified in such Officers’ Certificate, supplemental Indenture or such resolution.

Section 2.17 . Defaulted Interest. Any interest on any Debt Security of a particular series which is payable, but is not punctually paid or duly provided for, on the dates and in the manner provided in the Debt Securities of such series and in this Indenture (herein called “ Defaulted Interest ”) shall forthwith cease to be payable to the Registered Holder thereof on the relevant record date by virtue of having been such Registered Holder, and such Defaulted Interest may be paid by the Company, at its election in each case, as provided in clause (a) or (b) below:

(a) The Company may elect to make payment of any Defaulted Interest to the Persons in whose names the Registered Securities of such series are registered at the close of business on a special record date for the payment of such Defaulted Interest, which shall be fixed in the following manner: The Company shall notify the Trustee in writing of the amount of Defaulted Interest proposed to be paid on each such Registered Security of such series and the date of the proposed payment, and at the same time the Company shall deposit with the Trustee an amount of money equal to the aggregate amount proposed to be paid in respect of such Defaulted Interest or shall make arrangements satisfactory to the Trustee for such deposit prior to the date of the proposed payment, such money when deposited to be held in trust for the benefit of the Persons entitled to such Defaulted Interest as in this clause provided. Thereupon the Trustee shall fix a special record date for the payment of such Defaulted Interest which shall be not more than 15 days and not less than 10 days prior to the date of the proposed payment and not less than 10 days after the receipt by the Trustee of the notice of the proposed payment. The Trustee shall promptly notify the Company of such special record date and, in the name and at the expense of the Company, shall cause notice of the proposed payment of such Defaulted Interest and the special record date therefor to be mailed, first class postage prepaid, to each Holder thereof at its address as it appears in the Debt Security Register, not less than 10 days prior to such special record date. Notice of the proposed payment of such Defaulted Interest and the special record date therefor having been so mailed, such Defaulted interest shall be paid to the Persons in whose names the Registered Securities of such series are registered at the close of business on such special record date.

(b) The Company may make payment of any Defaulted Interest on the Registered Securities of such series in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Registered Securities of such series may be listed, and upon such notice as may be required by such exchange, if, after notice given by the Company to the Trustee of the proposed payment pursuant to this clause, such manner of payment shall be deemed practicable by the Trustee.

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Section 2.18 . Judgments. The Company may provide pursuant to Section 2.03 for Debt Securities of any series that (a) the obligation, if any, of the Company to pay the principal of, and premium, if any, and interest on, the Debt Securities of any series in a Foreign Currency or Dollars (the “ Designated Currency ”) as may be specified pursuant to Section 2.03 is of the essence and agrees that, to the fullest extent possible under applicable law, judgments in respect of Debt Securities of such series shall be given in the Designated Currency; (b) the obligation of the Company to make payments in the Designated Currency of the principal of, and premium, if any, and interest on, such Debt Securities shall, notwithstanding any payment in any other Currency (whether pursuant to a judgment or otherwise), be discharged only to the extent of the amount in the Designated Currency that the Holder receiving such payment may, in accordance with normal banking procedures, purchase with the sum paid in such other Currency (after any premium and cost exchange) on the business day in the country of issue of the Designated Currency or in the international banking community (in the case of a composite currency) immediately following the day on which such Holder receives such payment; (c) if the amount in the Designated Currency that may be so purchased for any reason falls short of the amount originally due, the Company shall pay such additional amounts as may be necessary to compensate for such shortfall; and (d) any obligation of the Company not discharged by such payment shall be due as a separate and independent obligation and, until discharged as provided herein, shall continue in full force and effect.

ARTICLE 3

R EDEMPTION OF D EBT S ECURITIES

Section 3.01 . Applicability of Article. The provisions of this Article shall be applicable to the Debt Securities of any series which are redeemable before their Stated Maturity except as otherwise specified as contemplated by Section 2.03 for Debt Securities of such series.

Section 3.02 . Notice of Redemption; Selection of Debt Securities. In case the Company shall desire to exercise the right to redeem all or any part of the Debt Securities of any series, as the case may be, in accordance with their terms, the Company shall fix a date for redemption and shall give notice of such redemption at least 30 and not more than 60 days prior to the date fixed for redemption to the Holders of Debt Securities of such series so to be redeemed as a whole or in part, in the manner provided in Section 13.03. The notice if given in the manner herein provided shall be conclusively presumed to have been duly given, whether or not the Holder receives such notice. In any case, failure to give such notice or any defect in the notice to the Holder of any Debt Security of a series designated for redemption as a whole or in part shall not affect the validity of the proceedings for the redemption of any other Debt Security of such series.

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Each such notice of redemption shall specify the date fixed for redemption, the redemption price at which Debt Securities of such series are to be redeemed, the Place or Places of Payment that payment will be made upon presentation and surrender of such Debt Securities, that any interest accrued to the date fixed for redemption will be paid as specified in said notice, that the redemption is for a sinking fund payment (if applicable), that, if the Company defaults on making such redemption payment or if the Debt Securities of that series are subordinated pursuant to the terms of Article 12 the paying agent is prohibited from making such payment pursuant to the terms of this Indenture, that on and after said date any interest thereon or on the portions thereof to be redeemed will cease to accrue, that in the case of Original Issue Discount Securities original issue discount accrued after the date fixed for redemption will cease to accrue, the provision of the Debt Securities of that series pursuant to which the Debt Securities of that series are being redeemed, the CUSIP numbers of the Debt Securities of that series being redeemed and that no representation is made as to the correctness or accuracy of the CUSIP number listed in such notice or printed on the Debt Securities of that series. In case any Debt Security of a series is to be redeemed in part only, the notice of redemption shall state the portion of the principal amount thereof to be redeemed and shall state that on and after the date fixed for redemption, upon surrender of such Debt Security, a new Debt Security or Debt Securities of that series in principal amount equal to the unredeemed portion thereof will be authenticated and delivered in exchange for the unredeemed portion of the principal of the Debt Security so surrendered.

At least 60 days before the redemption date unless the Trustee consents to a shorter period, the Company shall give notice to the Trustee of the redemption date, the principal amount of Debt Securities to be redeemed and the series and terms of the Debt Securities pursuant to which such redemption will occur. Such notice shall be accompanied by an Officers’ Certificate and an Opinion of Counsel from the Company to the effect that such redemption will comply with the conditions herein.

Notice of such redemption or purchase of Notes to be so redeemed or purchased at the election of the Company shall be given by the Company or, at the Company’s request (made to the Trustee at least 5 business days (or such shorter period as shall be satisfactory to the Trustee) prior to the date such notice is to be sent), by the Trustee in the name and at the expense of the Company. Any such request will include the notice which the Trustee is requested to send.

On or prior to the redemption date for any Registered Securities, the Company shall deposit with the Trustee or with a paying agent (or, if the Company is acting as its own paying agent, segregate and hold in trust) an amount of money in the Currency in which such Debt Securities are denominated (except as provided pursuant to Section 2.03) sufficient to pay the redemption price of such Registered Securities or any portions thereof that are to be redeemed on that date.

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If less than all the Debt Securities of like tenor and terms of a series are to be redeemed (other than pursuant to mandatory sinking fund redemptions), the Trustee shall select, in such manner as in its sole discretion it shall deem appropriate and fair, the Debt Securities of that series or portions thereof (in authorized denominations) to be redeemed. In any case where more than one Registered Security of such series is registered in the same name, the Trustee in its discretion may treat the aggregate principal amount so registered as if it were represented by one Registered Security of such series. The Trustee shall promptly notify the Company in writing of the Debt Securities selected for redemption and, in the case of any Debt Securities selected for partial redemption, the principal amount thereof to be redeemed. If any Debt Security called for redemption shall not be so paid upon surrender thereof on such redemption date, the principal, premium, if any, and interest shall bear interest until paid from the redemption date at the rate borne by the Debt Securities of that series. If less than all the Debt Securities of unlike tenor and terms of a series are to be redeemed, the particular Debt Securities to be redeemed shall be selected by the Company. Provisions of this Indenture that apply to Debt Securities called for redemption also apply to portions of Debt Securities called for redemption.

Section 3.03 . Payment of Debt Securities Called for Redemption. If notice of redemption has been given as provided in Section 3.02, the Debt Securities or portions of Debt Securities of the series with respect to which such notice has been given shall become due and payable on the date and at the Place or Places of Payment stated in such notice at the applicable redemption price, together with any interest accrued to the date fixed for redemption, and on and after said date (unless the Company shall default in the payment of such Debt Securities at the applicable redemption price, together with any interest accrued to said date) any interest on the Debt Securities or portions of Debt Securities of any series so called for redemption shall cease to accrue and any original issue discount in the case of Original Issue Discount Securities shall cease to accrue. On presentation and surrender of such Debt Securities at the Place or Places of Payment in said notice specified, the said Debt Securities or the specified portions thereof shall be paid and redeemed by the Company at the applicable redemption price, together with any interest accrued thereon to the date fixed for redemption.

Any Debt Security that is to be redeemed only in part shall be surrendered at the corporate trust office of the Trustee or such other office or agency of the Company as is specified pursuant to Section 2.03, with, if the Company, the Registrar or the Trustee so requires, due endorsement by, or a written instrument of transfer in form satisfactory to the Company, the Registrar and the Trustee duly executed by, the Holder thereof or his attorney duly authorized in writing, and the Company shall execute, and the Trustee shall authenticate and deliver to the Holder of such Debt Security without service charge, a new Debt Security or Debt Securities of the same series, of like tenor and form, of any authorized denomination as requested by such Holder in aggregate principal amount equal to and in exchange for the unredeemed portion of the principal of the Debt Security

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so surrendered; except that if a Global Security is so surrendered, the Company shall execute, and the Trustee shall authenticate and deliver to the Depositary for such Global Security, without service charge, a new Global Security in a denomination equal to and in exchange for the unredeemed portion of the principal of the Global Security so surrendered. In the case of a Debt Security providing appropriate space for such notation, at the option of the Holder thereof, the Trustee, in lieu of delivering a new Debt Security or Debt Securities as aforesaid, may make a notation on such Debt Security of the payment of the redeemed portion thereof.

Section 3.04 . Mandatory and Optional Sinking Funds. The minimum amount of any sinking fund payment provided for by the terms of Debt Securities of any series, resolution of the Board of Directors or a supplemental Indenture is herein referred to as a “mandatory sinking fund payment”, and any payment in excess of such minimum amount provided for by the terms of Debt Securities of any series, resolution of the Board of Directors or a supplemental Indenture is herein referred to as an “optional sinking fund payment”.

In lieu of making all or any part of any mandatory sinking fund payment with respect to any Debt Securities of a series in cash, the Company may at its option (a) deliver to the Trustee Debt Securities of that series theretofore purchased or otherwise acquired by the Company or (b) receive credit for the principal amount of Debt Securities of that series which have been redeemed either at the election of the Company pursuant to the terms of such Debt Securities or through the application of permitted optional sinking fund payments pursuant to the terms of such Debt Securities, resolution or supplemental Indenture; provided , that such Debt Securities have not been previously so credited. Such Debt Securities shall be received and credited for such purpose by the Trustee at the redemption price specified in such Debt Securities, resolution or supplemental Indenture for redemption through operation of the sinking fund and the amount of such mandatory sinking fund payment shall be reduced accordingly.

Section 3.05 . Redemption of Debt Securities for Sinking Fund. Not less than 60 days prior to each sinking fund payment date for any series of Debt Securities, the Company will deliver to the Trustee an Officers’ Certificate specifying the amount of the next ensuing sinking fund payment for that series pursuant to the terms of that series, the portion thereof, if any, which is to be satisfied by payment of cash in the Currency in which the Debt Securities of such series are denominated (except as provided pursuant to Section 2.03) and the portion thereof, if any, which is to be satisfied by delivering and crediting Debt Securities of that series pursuant to this Section 3.05 (which Debt Securities, if not previously redeemed, will accompany such certificate), the basis for such credit and that such Debt Securities have not been previously so credited and whether the Company intends to exercise its right to make any permitted optional sinking fund payment with respect to such series. Such certificate shall also state that no Event of Default has occurred and is continuing with respect to such series. Such certificate shall be irrevocable and upon its delivery the Company shall be

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obligated to make the cash payment or payments therein referred to, if any, on or before the next succeeding sinking fund payment date. Failure of the Company to deliver such certificate (or to deliver the Debt Securities specified in this paragraph) shall not constitute a Default, but such failure shall require that the sinking fund payment due on the next succeeding sinking fund payment date for that series shall be paid entirely in cash and shall be sufficient to redeem the principal amount of such Debt Securities subject to a mandatory sinking fund payment without the option to deliver or credit Debt Securities as provided in this Section 3.05 and without the right to make any optional sinking fund payment, if any, with respect to such series.

Any sinking fund payment or payments (mandatory or optional) made in cash plus any unused balance of any preceding sinking fund payments made in cash which shall equal or exceed $100,000 (or a lesser sum if the Company shall so request) with respect to the Debt Securities of any particular series shall be applied by the Trustee on the sinking fund payment date on which such payment is made (or, if such payment is made before a sinking fund payment date, on the sinking fund payment date following the date of such payment) to the redemption of such Debt Securities at the redemption price specified in such Debt Securities, resolution or supplemental Indenture for operation of the sinking fund together with any accrued interest to the date fixed for redemption. Any sinking fund moneys not so applied or allocated by the Trustee to the redemption of Debt Securities shall be added to the next cash sinking fund payment received by the Trustee for such series and, together with such payment, shall be applied in accordance with the provisions of this Section 3.05. Any and all sinking fund moneys with respect to the Debt Securities of any particular series held by the Trustee on the last sinking fund payment date with respect to Debt Securities of such series and not held for the payment or redemption of particular Debt Securities shall be applied by the Trustee, together with other moneys, if necessary, to be deposited sufficient for the purpose, to the payment of the principal of the Debt Securities of that series at its Stated Maturity.

The Trustee shall select the Debt Securities to be redeemed upon such sinking fund payment date in the manner specified in the last paragraph of Section 3.02 and the Company shall cause notice of the redemption thereof to be given in the manner provided in Section 3.02 except that the notice of redemption shall also state that the Debt Securities are being redeemed by operation of the sinking fund. Such notice having been duly given, the redemption of such Debt Securities shall be made upon the terms and in the manner stated in Section 3.03.

At least one business day before each sinking fund payment date, the Company shall pay to the Trustee (or, if the Company is acting as its own paying agent, the Company shall segregate and hold in trust) in cash a sum in the Currency in which the Debt Securities of such series are denominated (except as provided pursuant to Section 2.03) equal to any interest accrued to the date fixed for redemption of Debt Securities or portions thereof to be redeemed on such sinking fund payment date pursuant to this Section 3.05.

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The Trustee shall not redeem any Debt Securities of a series with sinking fund moneys or mail any notice of redemption of such Debt Securities by operation of the sinking fund for such series during the continuance of a Default in payment of interest on such Debt Securities or of any Event of Default (other than an Event of Default occurring as a consequence of this paragraph) with respect to such Debt Securities, except that if the notice of redemption of any such Debt Securities shall theretofore have been mailed in accordance with the provisions hereof, the Trustee shall redeem such Debt Securities if cash sufficient for that purpose shall be deposited with the Trustee for that purpose in accordance with the terms of this Article 3. Except as aforesaid, any moneys in the sinking fund for such series at the time when any such Default or Event of Default shall occur and any moneys thereafter paid into such sinking fund shall, during the continuance of such Default or Event of Default, be held as security for the payment of the Debt Securities of such series; provided , however , that in case such Event of Default or Default shall have been cured or waived as provided herein, such moneys shall thereafter be applied on the next sinking fund payment date for such Debt Securities on which such moneys may be applied pursuant to the provisions of this Section 3.05.

ARTICLE 4

P ARTICULAR C OVENANTS OF THE C OMPANY

Section 4.01 . Payment of Principal of, and Premium If Any, and Interest on, Debt Securities. The Company, for the benefit of each series of Debt Securities, will duly and punctually pay or cause to be paid the principal of, and premium, if any, and interest on, each of the Debt Securities at the place, at the respective times and in the manner provided herein and in the Debt Securities. Each installment of interest on the Debt Securities may at the Company’s option be paid by mailing checks for such interest payable to the Person entitled thereto to the address of such Person as it appears on the Debt Security Register maintained pursuant to Section 2.07(a) or, if provided pursuant to Section 2.03 and in accordance with arrangements satisfactory to the Trustee, at the option of the Registered Holder by wire transfer to an account designated by the Registered Holder. Principal, premium and interest of Debt Securities of any series shall be considered paid on the date due if on such date the Trustee or any paying agent holds in accordance with this Indenture money sufficient to pay in the Currency in which the Debt Securities of such series are denominated (except as provided pursuant to Section 2.03) all principal, premium and interest then due and, in the case of Debt Securities subordinated pursuant to the terms of Article 12, the Trustee or such paying agent, as the case may be, is not prohibited from paying such money to the Holders on that date pursuant to the terms of the Indenture.

The Company shall pay interest on overdue principal at the rate specified therefor in the Debt Securities and it shall pay interest on overdue installments of interest at the same rate to the extent lawful.

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Section 4.02 . Maintenance of Offices or Agencies for Registration of Transfer, Exchange and Payment of Debt Securities. The Company will maintain in each Place of Payment for any series of Debt Securities, an office or agency where Debt Securities of such series may be presented or surrendered for payment, where Debt Securities of such series may be surrendered for registration of transfer or exchange and where notices and demands to or upon the Company in respect of the Debt Securities of such series and this Indenture may be served. The Company will give prompt written notice to the Trustee of the location, and any change in the location, of such office or agency. If at any time the Company shall fail to maintain any such required office or agency or shall fail to furnish the Trustee with the address thereof, such presentations, surrenders, notices and demands may be made or served at the corporate trust office of the Trustee, and the Company hereby appoints the Trustee as its agent to receive all presentations, surrenders, notices and demands.

The Company may also from time to time designate different or additional offices or agencies to be maintained for such purposes (in or outside of such Place of Payment), and may from time to time rescind any such designation; provided , however , that no such designation or rescission shall in any manner relieve the Company of its obligations described in the preceding paragraph. The company will give prompt written notice to the Trustee of any such additional designation or rescission of designation and any change in the location of any such different or additional office or agency.

Section 4.03 . Appointment to Fill a Vacancy in the Office of Trustee. The Company, whenever necessary to avoid or fill a vacancy in the office of Trustee, will appoint, in the manner provided in Section 7.08, a Trustee, so that there shall at all times be a Trustee hereunder with respect to each series of Debt Securities.

Section 4.04. Duties Of Paying Agents, etc .

(a) The Company shall cause each paying agent, if any, other than the Trustee, to execute and deliver to the Trustee an instrument in which such agent shall agree with the Trustee, subject to the provisions of this Section 4.04,

(i) that it will hold all sums held by it as such agent for the payment of the principal of, and premium, if any, or interest on, the Debt Securities of any series (whether such sums have been paid to it by the Company or by any other obligor on the Debt Securities of such series) in trust for the benefit of the Holders of the Debt Securities of such series;

(ii) that it will give the Trustee notice of any failure by the Company (or by any other obligor on the Debt Securities of such series) to make any payment of the principal of and premium, if any, or interest on, the Debt Securities of such series when the same shall be due and payable; and

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(iii) that it will at any time during the continuance of an Event of Default, upon the written request of the Trustee, forthwith pay to the Trustee all sums so held by it as such agent.

(b) If the Company shall act as its own paying agent, it will, on or before each due date of the principal of, and premium, if any, or interest, if any, on, the Debt Securities of any series, set aside, segregate and hold in trust for the benefit of the Holders of the Debt Securities of such series a sum sufficient to pay such principal, premium, if any, or interest so becoming due. The Company will promptly notify the Trustee of any failure by the Company to take such action or the failure by any other obligor on such Debt Securities to make any payment of the principal of, and premium, if any, or interest on, such Debt Securities when the same shall be due and payable.

(c) Anything in this Section 4.04 to the contrary notwithstanding, the Company may, at any time, for the purpose of obtaining a satisfaction and discharge of this Indenture, or for any other reason, pay or cause to be paid to the Trustee all sums held in trust by it or any paying agent, as required by this Section 4.04, such sums to be held by the Trustee upon the same trusts as those upon which such sums were held by the Company or such paying agent.

(d) Whenever the Company shall have one or more paying agents with respect to any series of Debt Securities, it will, prior to each due date of the principal of, and premium, if any, or interest on, any Debt Securities of such series, deposit with any such paying agent a sum sufficient to pay the principal, premium or interest so becoming due, such sum to be held in trust for the benefit of the Persons entitled thereto, and (unless any such paying agent is the Trustee) the Company will promptly notify the Trustee of its action or failure so to act.

(e) Anything in this Section 4.04 to the contrary notwithstanding, the agreement to hold sums in trust as provided in this Section 4.04 is subject to the provisions of Section 11.05.

Section 4.05 . Statement by Officers as to Default. The Company will deliver to the Trustee, on or before a date not more than four months after the end of each fiscal year of the Company (currently on a calendar year basis) ending after the date hereof, an Officers’ Certificate, one of the signatories of which shall be the Company’s principal executive officer, principal accounting officer or principal financial officer, stating, as to each officer signing such certificate, that (i) in the course of his performance of his duties as an officer of the Company he would normally have knowledge of any Default, (ii) whether or not to the best of his knowledge any Default occurred during such year and (iii) if to the best of his knowledge the Company is in Default, specifying all such Defaults and what action the Company is taking or proposes to take with respect thereto. The Company also shall comply with Section 314(a)(4) of the Trust Indenture Act.

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Section 4.06 . Further Instruments and Acts. The Company will, upon request of the Trustee, execute and deliver such further instruments and do such further acts as may reasonably be necessary or proper to carry out more effectually the purposes of this Indenture.

Section 4.07 . Existence. Subject to Article 10, the Company will do or cause to be done all things necessary to preserve and keep in full force and effect its existence and rights (charter and statutory); provided , however , that the Company shall not be required to preserve any such right or franchise if the Company shall determine that the preservation thereof is no longer desirable in the conduct of the business of the Company and that the loss thereof is not disadvantageous in any material respect to the Holders.

Section 4.08 . Maintenance of Properties. The Company will cause all properties used or useful in the conduct of its business or the business of any Subsidiary to be maintained and kept in good condition, repair and working order in all material respects and will cause to be made all necessary repairs, renewals, replacements, betterments and improvements thereof, all as in the judgment of the Company may be necessary so that the business carried on by the Company and its subsidiaries may be properly and advantageously conducted at all times; provided , however , that nothing in this Section shall prevent the Company or a Subsidiary from discontinuing the operation or maintenance of any of such properties if such discontinuance is, in the judgment of the Company, not materially detrimental to the conduct of the business of the Company and its Subsidiaries, taken as a whole, and not disadvantageous in any material respect to the Holders.

Section 4.09 . Payment of Taxes and Other Claims. The Company will pay or discharge or cause to be paid or discharged, before the same shall become delinquent, (1) all taxes, assessments and governmental charges levied or imposed upon the Company or any Subsidiary or upon the income, profits or property of the Company or any Subsidiary, and (2) all lawful claims for labor, materials and supplies which, if unpaid, might by law become a Lien upon the property of the Company or any Subsidiary, provided , however , that the Company shall not be required to pay or discharge or cause to be paid or discharged any such tax, assessment, charge or claim whose amount, applicability or validity is being contested in good faith by appropriate proceedings.

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ARTICLE 5

H OLDERS ’ L ISTS AND R EPORTS BY THE C OMPANY AND THE T RUSTEE

Section 5.01 . Company to Furnish Trustee Information as to Names and Addresses of Holders; Preservation of Information. The Company covenants and agrees that it will furnish or cause to be furnished to the Trustee with respect to the Registered Securities of each series:

(a) not more than 15 days after each record date with respect to the payment of interest, if any, a list, in such form as the Trustee may reasonably require, of the names and addresses of the Registered Holders as of such record date, and

(b) at such other times as the Trustee may request in writing, within 30 days after the receipt by the Company of any such request, a list as of a date not more than 15 days prior to the time such list is furnished;

provided , however , that so long as the Trustee shall be the Registrar, such lists shall not be required to be furnished.

The Trustee shall preserve, in as current a form as is reasonably practicable, all information as to the names and addresses of the Holders (1) contained in the most recent list furnished to it as provided in this Section 5.01 or (2) received by it in the capacity of paying agent or Registrar (if so acting) hereunder.

The Trustee may destroy any list furnished to it as provided in this Section 5.01 upon receipt of a new list so furnished.

Section 5.02 . Communications to Holders. Holders may communicate pursuant to Section 312(b) of the Trust Indenture Act with other Holders with respect to their rights under this Indenture or the Debt Securities. The Company, the Trustee, the Registrar and anyone else shall have the protection of Section 312(c) of the Trust Indenture Act.

Section 5.03 . Reports by Company.

(a) The Company covenants and agrees, and any obligor hereunder shall covenant and agree, to file with the Trustee, within 15 days after the Company or such obligor, as the case may be, is required to file the same with the Securities and Exchange Commission, copies of the annual reports and of the information, documents and other reports (or copies of such portions of any of the foregoing as said Commission may from time to time by rules and regulations prescribe) which the Company or such obligor, as the case may be, may be required to file with said Commission pursuant to Section 13 or Section 15(d) of the Exchange Act; or, if the Company or such obligor, as the case may be, is not required to file information, documents or reports pursuant to either of such Sections, then to file with the Trustee and said Commission, in accordance with rules and regulations prescribed from time to time by said Commission, such of the supplementary and periodic information, documents and reports which may be required pursuant to Section 13 of the Exchange Act in respect of a security listed and registered on a national securities exchange as may be prescribed from time to time in such rules and regulations.

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(b) The Company covenants and agrees, and any obligor hereunder shall covenant and agree, to file with the Trustee and the Securities and Exchange Commission, in accordance with the rules and regulations prescribed from time to time by said Commission, such additional information, documents, and reports with respect to compliance by the Company or such obligor, as the case may be, with the conditions and covenants provided for in this Indenture as may be required from time to time by such rules and regulations.

(c) Delivery of such information, documents and reports to the Trustee is for informational purposes only and the Trustee’s receipt of such shall not constitute constructive notice of any information contained therein or determinable from information contained therein, including the Company’s compliance with any of its covenants hereunder (as to which the Trustee is entitled to rely exclusively on Officers’ Certificates).

Section 5.04 . Reports by Trustee. Within 60 days after May 15 of each year commencing with the first May 15 after the first issuance of Debt Securities pursuant to this Indenture, the Trustee shall transmit to the Holders, in the manner and to the extent provided in Section 313(c) of the Trust Indenture Act, a brief report dated as of such May 15 if required by Section 313(a) of the Trust Indenture Act.

The Trustee shall comply with Sections 313(b) and 313(c) of the Trust Indenture Act.

A copy of each report at the time of its mailing to Holders shall be filed with the Securities and Exchange Commission and each stock exchange (if any) on which the Debt Securities of any series are listed (to the extent such listing is known to the Trustee). The Company agrees to notify promptly the Trustee whenever the Debt Securities of any series become listed on any stock exchange and of any delisting thereof.

Section 5.05 . Record Dates for Action by Holders. If the Company shall solicit from the Holders of Debt Securities of any series any action (including the making of any demand or request, the giving of any direction, notice, consent or waiver or the taking of any other action), the Company may, at its option, by resolution of the Board of Directors, fix in advance a record date for the determination of Holders of Debt Securities entitled to take such action, but the Company shall have no obligation to do so. Any such record date shall be fixed at the Company’s discretion. If such a record date is fixed, such action may be sought or given before or after the record date, but only the Holders of Debt Securities of record at the close of business on such record date shall be deemed to be Holders of Debt Securities for the purpose of determining whether Holders of the requisite proportion of Debt Securities of such series Outstanding have authorized or agreed or consented to such action, and for that purpose the Debt Securities of such series Outstanding shall be computed as of such record date.

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ARTICLE 6

R EMEDIES OF THE T RUSTEE AND H OLDERS IN E VENT OF D EFAULT

Section 6.01 . Events of Default. If any one or more of the following shall have occurred and be continuing with respect to Debt Securities of any series (each of the following, an “ Event of Default ”):

(a) default in the payment of any installment of interest upon any Debt Securities of that series as and when the same shall become due and payable, whether or not such payment shall be prohibited by Article 12, if applicable, and continuance of such default for a period of 30 days; or

(b) default in the payment of the principal of or premium, if any, on any Debt Securities of that series as and when the same shall become due and payable, whether at maturity, upon redemption, by declaration, upon required repurchase or otherwise, whether or not such payment shall be prohibited by Article 12, if applicable; or

(c) default in the payment of any sinking fund payment with respect to any Debt Securities of that series as and when the same shall become due and payable; or

(d) failure on the part of the Company to comply with Article 10; or

(e) failure on the part of the Company duly to observe or perform any other of the covenants or agreements on the part of the Company in the Debt Securities of that series, in any resolution of the Board of Directors authorizing the issuance of that series of Debt Securities, in this Indenture with respect to such series or in any supplemental Indenture with respect to such series (other than a covenant a default in the performance of which is elsewhere in this Section specifically dealt with), continuing for a period of 60 days after the date on which written notice, specifying such failure, requiring the Company to remedy the same and stating that such written notice is a “Notice of Default” hereunder, shall have been given by registered or certified mail to the Company by the Trustee or to the Company and the Trustee by the Holders of at least 25% in aggregate principal amount of the Debt Securities of that series at the time Outstanding; or

(f) Indebtedness of the Company or any Subsidiary of the Company is not paid within any applicable grace period after final maturity or is accelerated by the holders thereof because of a default, the total amount of such Indebtedness unpaid or accelerated exceeds $25,000,000 or its Dollar Equivalent at the time and such default remains uncured or such acceleration is not rescinded for 10 days after the date on which written notice specifying such failure and requiring the

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Company to remedy the same shall have been given, by registered or certified mail, to the Company by the Trustee or to the Company and the Trustee by the Holders of at least 25% in aggregate principal amount of the Debt Securities of that series at the time Outstanding; or

(g) the Company or any Significant Subsidiary shall (i) voluntarily commence any proceeding or file any petition seeking relief under Title 11 of the United States Code or any other Federal or State bankruptcy, insolvency or similar law, (ii) consent to the institution of, or fail to controvert within the time and in the manner prescribed by law, any such proceeding or the filing of any such petition, (iii) apply for or consent to the appointment of a receiver, trustee, custodian, sequestrator or similar official for the Company or any Significant Subsidiary or for a substantial part of the Company’s or any Significant Subsidiary’s property, (iv) file an answer admitting the material allegations of a petition filed against the Company or any Significant Subsidiary in any such proceeding, (v) make a general assignment for the benefit of creditors, (vi) admit in writing the Company’s or any Significant Subsidiary’s inability or fail generally to pay the Company’s or any Significant Subsidiary’s debts as they become due, (vii) take corporate action for the purpose of effecting any of the foregoing, or (viii) take any comparable action under any foreign laws relating to insolvency; or

(h) the entry of an order or decree by a court having competent jurisdiction in the premises for (i) relief in respect of the Company or any Significant Subsidiary or a substantial part of the Company’s or any Significant Subsidiary’s property under Title 11 or the United States Code or any other Federal or State bankruptcy, insolvency or similar law, (ii) the appointment of a receiver, trustee, custodian, sequestrator or similar official for the Company or any Significant Subsidiary or for a substantial part of the Company’s or any Significant Subsidiary’s property, or (iii) the winding-up or liquidation of the Company or any Significant Subsidiary; and such order or decree shall continue unstayed and in effect for 60 consecutive days; or any similar relief is granted under any foreign laws and the order or decree stays in effect for 60 consecutive days; or

(i) any other Event of Default provided under the terms of the Debt Securities of that series;

then and in each and every case that an Event of Default with respect to Debt Securities of that series at the time outstanding occurs and is continuing (other than an Event of Default arising under Section 6.01(g) or (h)), unless the principal of and interest on all the Debt Securities of that series shall have already become due and payable, either the Trustee or the Holders of not less than 25% in aggregate principal amount of the Debt Securities of that series then Outstanding hereunder, by notice in writing to the Company (and to the Trustee if given by Holders), may declare the principal of (or, if the Debt Securities of that series are Original Issue Discount Debt Securities, such portion of the principal amount as

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may be specified in the terms of that series) and interest on all the Debt Securities of that series to be due and payable immediately, and upon any such declaration the same shall become and shall be immediately due and payable, anything in this Indenture or in the Debt Securities of that series contained to the contrary notwithstanding. If an Event of Default under Section 6.01(g) or (h) occurs, then the principal of, premium, if any, and accrued interest on the Debt Securities shall become immediately due and payable without any declaration or other act on the part of the Trustee or any Holder.

The Holders of a majority in principal amount of the Debt Securities of a particular series by notice to the Trustee may rescind an acceleration and its consequences if the rescission would not conflict with any judgment or decree already rendered and if all existing Events of Default have been cured or waived except nonpayment of principal or interest that has become due solely because of acceleration and if the Company shall have paid or deposited with the Trustee a sum sufficient to pay all sums paid or advanced by the Trustee hereunder and the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel. Upon any such rescission, the parties hereto shall be restored respectively to their several positions and rights hereunder, and all rights, remedies and powers of the parties hereto shall continue as though no proceeding had been taken.

In case the Trustee or any Holder shall have proceeded to enforce any right under this Indenture and such proceedings shall have been discontinued or abandoned because of such rescission or annulment or for any other reason or shall have been determined adversely to the Trustee or such Holder, then and in every such case the parties hereto shall be restored respectively to their several positions and rights hereunder, and all rights, remedies and powers of the parties hereto shall continue as though no such proceeding had been taken.

The foregoing Events of Default shall constitute Events of Default whatever the reason for any such Event of Default and whether it is voluntary or involuntary or is effected by operation of law or pursuant to any judgment, decree or order of any court or any order, rule or regulation of any administrative or governmental body.

The Company shall deliver to the Trustee, within 30 days after the occurrence thereof, written notice in the form of an Officers’ Certificate of any event which with the giving of notice and the lapse of time would become an Event of Default under clause (c), (d), (e), (f), (g), (h) or (i) (or any other events of default provided for in any indenture supplemental hereto), its status and what action the Company is taking or proposes to take with respect thereto.

Section 6.02 . Collection of Indebtedness by Trustee, etc. If an Event of Default occurs and is continuing, the Trustee, in its own name and as trustee of an express trust, shall be entitled and empowered to institute any action or proceedings at law or in equity for the collection of the sums so due and unpaid or

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enforce the performance of any provision of the Debt Securities of the affected series or this Indenture, and may prosecute any such action or proceedings to judgment or final decree, and may enforce any such judgment or final decree against the Company or any other obligor upon the Debt Securities of such series (and collect in the manner provided by law out of the property of the Company or any other obligor upon the Debt Securities of such series wherever situated the moneys adjudged or decreed to be payable).

In case there shall be pending proceedings for the bankruptcy or for the reorganization of the Company or any other obligor upon the Debt Securities of any series under Title 11 of the United States Code or any other Federal or State bankruptcy, insolvency or similar law, or in case a receiver, trustee or other similar official shall have been appointed for its property, or in case of any other similar judicial proceedings relative to the Company or any other obligor upon the Debt Securities of any series, its creditors or its property, the Trustee, irrespective of whether the principal of Debt Securities of any series shall then be due and payable as therein expressed or by declaration or otherwise and irrespective of whether the Trustee shall have made any demand pursuant to the provisions of this Section 6.02, shall be entitled and empowered, by intervention in such proceedings or otherwise, to file and prove a claim or claims for the whole amount of principal, premium, if any, and interest (or, if the Debt Securities of such series are Original Issue Discount Debt Securities, such portion of the principal amount as may be specified in the terms of such series) owing and unpaid in respect of the Debt Securities of such series, and to file such other papers or documents as may be necessary or advisable in order to have the claims of the Trustee (including any claim for reasonable compensation to the Trustee, its agents, attorneys and counsel, and for reimbursement of all expenses and liabilities Incurred, and all advances made, by the Trustee except as a result of its negligence or bad faith) and of the Holders thereof allowed in any such judicial proceedings relative to the Company, or any other obligor upon the Debt Securities of such series, its creditors or its property, and to collect and receive any moneys or other property payable or deliverable on any such claims, and to distribute all amounts received with respect to the claims of such Holders and of the Trustee on their behalf, and any receiver, assignee or trustee in bankruptcy or reorganization is hereby authorized by each of such Holders to make payments to the Trustee, and, in the event that the Trustee shall consent to the making of payments directly to such Holders, to pay to the Trustee such amount as shall be sufficient to cover reasonable compensation to the Trustee, its agents, attorneys and counsel, and all other reasonable expenses and liabilities Incurred, and all advances made, by the Trustee except as a result of its negligence or bad faith.

All rights of action and of asserting claims under this Indenture, or under any of the Debt Securities, of any series, may be enforced by the Trustee without the possession of any such Debt Securities or the production thereof in any trial or other proceedings relative thereto, and any such action or proceedings instituted by the Trustee shall be brought in its own name as trustee of an express trust, and

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any recovery of judgment (except for any amounts payable to the Trustee pursuant to Section 7.06) shall be for the ratable benefit of the Holders of all the Debt Securities in respect of which such action was taken.

In case of an Event of Default hereunder the Trustee may in its discretion proceed to protect and enforce the rights vested in it by this Indenture by such appropriate judicial proceedings as the Trustee shall deem most effectual to protect and enforce any of such rights, either at law or in equity or in bankruptcy or otherwise, whether for the specific enforcement of any covenant or agreement contained in this Indenture or in aid of the exercise of any power granted in this Indenture, or to enforce any other legal or equitable right vested in the Trustee by this Indenture or by law.

Nothing herein contained shall be deemed to authorize the Trustee to authorize or consent to or accept or adopt on behalf of any Holder any plan of reorganization, arrangement, adjustment or composition affecting the Notes or the rights of any Holder thereof, or to authorize the Trustee to vote in respect of the claim of any Holder in any such proceeding.

Section 6.03 . Application of Moneys Collected by Trustee. Any moneys or other property collected by the Trustee pursuant to Section 6.02 with respect to Debt Securities of any series shall be applied in the order following, at the date or dates fixed by the Trustee for the distribution of such moneys or other property, upon presentation of the several Debt Securities of such series in respect of which moneys or other property have been collected, and the notation thereon of the payment, if only partially paid, and upon surrender thereof if fully paid:

First : To the payment of all money due the Trustee hereunder, including pursuant to Section 7.06;

Second : As provided in Article 12, if applicable;

Third : In case the principal of the Outstanding Debt Securities in respect of which such moneys have been collected shall not have become due, to the payment of interest on the Debt Securities of such series in the order of the maturity of the installments of such interest, with interest (to the extent that such interest has been collected by the Trustee) upon the overdue installments of interest at the rate or Yield to Maturity (in the case of Original Issue Discount Debt Securities) borne by the Debt Securities of such series, such payments to be made ratably to the Persons entitled thereto, without discrimination or preference;

Fourth : In case the principal of the Outstanding Debt Securities in respect of which such moneys have been collected shall have become due, by declaration or otherwise, to the payment of the whole amount then owing and unpaid upon the Debt Securities of such series for principal and premium, if any, and interest, with interest on the overdue principal and premium, if any, and (to the extent that such interest has been collected by the Trustee) upon overdue installments of

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interest at the rate or Yield to Maturity (in the case of Original Issue Discount Debt Securities) borne by the Debt Securities of such series; and, in case such moneys shall be insufficient to pay in full the whole amount so due and unpaid upon the Debt Securities of such series, then to the payment of such principal and premium, if any, and interest, without preference or priority of principal and premium, if any, over interest, or of interest over principal and premium, if any, or of any installment of interest over any other installment of interest, or of any Debt Security of such series over any Debt Security of such series, ratably to the aggregate of such principal and premium, if any, and interest; and

Fifth : The remainder, if any, shall be paid to the Company, its successors or assigns, or to whomsoever may be lawfully entitled to receive the same, or as a court of competent jurisdiction may direct.

The Trustee may fix a record date and payment date for any payment to Holders pursuant to this Section 6.03. At least 15 days before such record date, the Company shall mail to each Holder and the Trustee a notice that states the record date, the payment date and amount to be paid.

Section 6.04 . Limitation on Suits by Holders. No Holder of any Debt Security of any series shall have any right by virtue or by availing of any provision of this Indenture to institute any action or proceeding at law or in equity or in bankruptcy or otherwise, upon or under or with respect to this Indenture, or for the appointment of a receiver or trustee, or for any other remedy hereunder, unless such Holder previously shall have given to the Trustee written notice of an Event of Default with respect to Debt Securities of that same series and of the continuance thereof and unless the Holders of not less than 25% in aggregate principal amount of the Outstanding Debt Securities of that series shall have made written request upon the Trustee to institute such action or proceedings in respect of such Event of Default in its own name as Trustee hereunder and shall have offered to the Trustee such indemnity as it may require against the costs, expenses and liabilities to be Incurred therein or thereby, and the Trustee, for 60 days after its receipt of such notice, request and offer of indemnity shall have failed to institute any such action or proceedings and no direction inconsistent with such written request shall have been given to the Trustee pursuant to Section 6.06; it being understood and intended, and being expressly covenanted by the Holder of every Debt Security with every other Holder and the Trustee, that no one or more Holders shall have any right in any manner whatever by virtue or by availing of any provision of this Indenture to affect, disturb or prejudice the rights of any Holders, or to obtain or seek to obtain priority over or preference to any other such Holder, or to enforce any right under this Indenture, except in the manner herein provided and for the equal, ratable and common benefit of all such Holders. For the protection and enforcement of the provisions of this Section 6.04, each and every Holder and the Trustee shall be entitled to such relief as can be given either at law or in equity.

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Notwithstanding any other provision in this Indenture, however, the right of any Holder of any Debt Security to receive payment of the principal of, and premium, if any, and (subject to Section 2.12) interest on, such Debt Security on or after the respective due dates expressed in such Debt Security, and to institute suit for the enforcement of any such payment on or after such respective dates, shall not be impaired or effected without the consent of such Holder.

Section 6.05 . Remedies Cumulative; Delay or Omission in Exercise of Rights Not a Waiver of Default. All powers and remedies given by this Article 6 to the Trustee or to the Holders shall, to the extent permitted by law, be deemed cumulative and not exclusive of any thereof or of any other powers and remedies available to the Trustee or the Holders, by judicial proceedings or otherwise, to enforce the performance or observance of the covenants and agreements contained in this Indenture, and no delay or omission of the Trustee or of any Holder to exercise any right or power accruing upon any Default occurring and continuing as aforesaid, shall impair any such right or power, or shall be construed to be a waiver of any such Default or an acquiescence therein; and, subject to the provisions of Section 6.04, every power and remedy given by this Article 6 or by law to the Trustee or to the Holders may be exercised from time to time, and as often as shall be deemed expedient, by the Trustee or by the Holders.

Section 6.06 . Rights of Holders of Majority in Principal Amount of Debt Securities to Direct Trustee and to Waive Default. The Holders of a majority in aggregate principal amount of the Debt Securities of any series at the time Outstanding shall have the right to direct the time, method, and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred on the Trustee, with respect to the Debt Securities of such series; provided , however , that such direction shall not be otherwise than in accordance with law and the provisions of this Indenture, and that subject to the provisions of Section 7.01, the Trustee shall have the right to decline to follow any such direction if the Trustee being advised by counsel shall determine that the action so directed may not lawfully be taken, or if the Trustee shall by a responsible officer or officers determine that the action so directed would involve it in personal liability or would be unjustly prejudicial to Holders of Debt Securities of such series not taking part in such direction; and provided further, however, that nothing in this Indenture contained shall impair the right of the Trustee to take any action deemed proper by the Trustee and which is not inconsistent with such direction by such Holders. The Holders of a majority in aggregate principal amount of the Debt Securities of that series at the time Outstanding may on behalf of the Holders of all the Debt Securities of that series waive any past Default or Event of Default and its consequences for that series specified in the terms thereof as contemplated by Section 2.03, except (i) a Default in the payment of the principal of, and premium, if any, or interest on, any of the Debt Securities and (ii) a Default in respect of a provision that under Section 9.02 cannot be amended without the consent of each Holder affected thereby. In case of any such waiver, such Default shall cease to exist, any Event

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of Default arising there from shall be deemed to have been cured for every purpose of this Indenture, and the Company, the Trustee and the Holders of the Debt Securities of that series shall be restored to their former positions and rights hereunder, respectively; but no such waiver shall extend to any subsequent or other Default or impair any right consequent thereon.

Section 6.07 . Trustee to Give Notice of Defaults Known to It, but May Withhold Such Notice in Certain Circumstances. If a Default occurs hereunder with respect to Debt Securities of any series, the Trustee will give the Holders of Debt Securities of such series notice of such Default as and to the extent provided by the Trust Indenture Act; provided, however , that in the case of any Default of the character specified in Section 6.01(e) with respect to Securities of such series no such notice to Holders will be given until at least 30 calendar days after the occurrence thereof. Except in the case of Default in the payment of the principal of, or premium, if any, or interest on, any of the Debt Securities of such series, the Trustee shall be protected in withholding such notice if and so long as the board of directors, the executive committee or a committee of directors or responsible officers of the Trustee in good faith determine that the withholding of such notice is in the interests of the Holders thereof.

Section 6.08 . Requirement of an Undertaking to Pay Costs in Certain Suits under the Indenture or Against the Trustee. All parties to this Indenture agree, and each Holder of any Debt Security by his acceptance thereof shall be deemed to have agreed, that any court may in its discretion require, in any suit for the enforcement of any right or remedy under this Indenture, or in any suit against the Trustee for any action taken or omitted by it as Trustee, the filing by any party litigant in such suit of an undertaking to pay the costs of such suit in the manner and to the extent provided in the Trust Indenture Act, and that such court may in its discretion assess reasonable costs, including reasonable attorneys’ fees, against any party litigant in such suit, having due regard to the merits and good faith of the claims or defenses made by such party litigant; but the provisions of this Section 6.08 shall not apply to any suit instituted by the Trustee, to any suit instituted by any Holder, or group of Holders, holding in the aggregate more than ten percent in principal amount of the Outstanding Debt Securities of that series or to any suit instituted by any Holder for the enforcement of the payment of the principal of, or premium, if any, or interest on, any Debt Security on or after the due date for such payment expressed in such Debt Security.

ARTICLE 7

C ONCERNING THE T RUSTEE

Section 7.01 . Certain Duties and Responsibilities. The Trustee, prior to the occurrence of an Event of Default and after the curing or waiving of all Events of Default which may have occurred, undertakes to perform such duties and only such duties as are specifically set forth in this Indenture. In case an Event of

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Default has occurred (which has not been cured or waived), the Trustee shall exercise such of the rights and powers vested in it by this Indenture, and use the same degree of care and skill in their exercise, as a prudent man would exercise or use under the circumstances in the conduct of his own affairs.

No provision of this Indenture shall be construed to relieve the Trustee from liability for its own negligent action, its own negligent failure to act, or its own willful misconduct, except that:

(a) this subsection shall not be construed to limit the effect of the first paragraph of this Section 7.01;

(b) prior to the occurrence of an Event of Default with respect to the Debt Securities of a series and after the curing or waiving of all Events of Default with respect to such series which may have occurred:

(i) the duties and obligations of the Trustee with respect to Debt Securities of such series shall be determined solely by the express provisions of this Indenture, and the Trustee shall not be liable except for the performance of such duties and obligations with respect to such series as are specifically set forth in this Indenture, and no implied covenants or obligations with respect to such series shall be read into this Indenture against the Trustee; and

(ii) in the absence of bad faith on the part of the Trustee, the Trustee may conclusively rely, as to the truth of the statements and the correctness of the opinions expressed therein, upon any certificates or opinions furnished to the Trustee and conforming to the requirements of this Indenture; but in the case of any such certificates or opinions which by any provision hereof are specifically required to be furnished to the Trustee, the Trustee shall be under a duty to examine the same to determine whether or not they conform to the requirements of this Indenture; but the Trustee shall examine the evidence furnished to it pursuant to Section 5.03 to determine whether or not such evidence conforms to the requirement of this Indenture;

(c) the Trustee shall not be liable for an error of judgment made in good faith by a responsible officer, unless it shall be proved that the Trustee was negligent in ascertaining the pertinent facts;

(d) the Trustee shall not be liable with respect to any action taken or omitted to be taken by it with respect to Debt Securities of any series in good faith in accordance with the direction of the Holders of not less than a majority in aggregate principal amount of the Outstanding Debt Securities of that series relating to the time, method and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred upon the Trustee, under this Indenture with respect to Debt Securities of such series; and

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(e) none of the provisions of this Indenture shall require the Trustee to expend or risk its own funds or otherwise incur any personal financial liability in the performance of any of its duties hereunder, or in the exercise of any of its rights or powers, if there shall be reasonable grounds for believing that repayment of such funds or adequate indemnity against such risk or liability is not reasonably assured to it.

Whether or not therein expressly so provided, every provision of this Indenture relating to the conduct or affecting the liability of or affording protection to the Trustee shall be subject to the provisions of this Section.

Section 7.02 . Certain Rights of Trustee . Except as otherwise provided in Section 7.01.

(a) the Trustee may rely and shall be protected in acting or refraining from acting upon any resolution, certificate, statement, instrument, opinion, report, notice, request, direction, consent, order, bond, debenture, note or other paper or document believed by it to be genuine and to have been signed or presented by the proper party or parties;

(b) any request, direction, order or demand of the Company mentioned herein shall be sufficiently evidenced by a Company Order (unless other evidence in respect thereof be herein specifically prescribed); and any resolution of the Board of Directors may be evidenced to the Trustee by a copy thereof certified by the Secretary or an Assistant Secretary of the Company;

(c) the Trustee may consult with counsel, and the advice of such counsel or any Opinion of Counsel shall be full and complete authorization and protection in respect of any action taken or suffered or omitted by it hereunder in good faith and in accordance with such advice or Opinion of Counsel;

(d) the Trustee shall be under no obligation to exercise any of the rights or powers vested in it by this Indenture at the request, order or direction of any of the Holders of Debt Securities of any series pursuant to the provisions of this Indenture, unless such Holders shall have offered to the Trustee reasonable security or indemnity against the costs, expenses and liabilities which may be Incurred therein or thereby;

(e) the Trustee shall not be liable for any action taken or omitted by it in good faith and reasonably believed by it to be authorized or within the discretion or rights or powers conferred upon it by this Indenture;

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(f) prior to the occurrence of an Event of Default and after the curing or waiving of all Events of Default which may have occurred, the Trustee shall not be bound to make any investigation into the facts or matters stated in any resolution, certificate, statement, instrument, opinion, report, notice, request, direction, consent, order, approval or other paper or document, unless requested in writing to do so by the Holders of a majority in aggregate principal amount of the then outstanding Debt Securities of a series affected by such matter; provided , however , that if the payment within a reasonable time to the Trustee of the costs, expenses or liabilities likely to be Incurred by it in the making of such investigation is not, in the opinion of the Trustee, reasonably assured to the Trustee by the security afforded to it by the terms of this Indenture, the Trustee may require indemnity against such costs, expenses or liabilities as a condition to so proceeding. The reasonable expense of every such investigation shall be paid by the Company or, if paid by the Trustee, shall be repaid by the Company upon demand;

(g) the Trustee may execute any of the trusts or powers hereunder or perform any duties hereunder either directly or by or through agents or attorneys and the Trustee shall not be responsible for any misconduct or negligence on the part of any agent or attorney appointed by it with due care hereunder;

(h) if any property other then cash shall at any time be subject to a Lien in favor of the Holders, the Trustee, if and to the extent authorized by a receivership or bankruptcy court of competent jurisdiction or by the supplemental instrument subjecting such property to such Lien, shall be entitled to make advances for the purpose of preserving such property or of discharging tax Liens or other prior Liens or encumbrances thereon;

(i) the Trustee shall not be liable for any action it takes or omits to take in good faith which it reasonably believes to be authorized or within its rights or powers under this Indenture;

(j) the permissive rights of the Trustee to do things enumerated in this Indenture shall not be construed as duties; and

(k) the rights, privileges, protections, immunities and benefits given to the Trustee, including its right to be indemnified, are extended to, and shall be enforceable by, the Trustee in each of its capacities hereunder, and to each agent, custodian and other Person employed to act hereunder.

Section 7.03 . Trustee Not Liable for Recitals in Indenture or in Debt Securities. The recitals contained herein and in the Debt Securities (except the Trustee’s certificate of authentication) shall be taken as the statements of the Company, and the Trustee assumes no responsibility for the correctness of the same. The Trustee makes no representations as to the validity or sufficiency of this Indenture or of the Debt Securities of any series, except that the Trustee represents that it is duly authorized to execute and deliver this Indenture, authenticate the Debt Securities and perform its obligations hereunder, and that the statements made by it or to be made by it in a Statement of Eligibility and

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Qualification on Form T-1 supplied to the Company are true and accurate. The Trustee shall not be accountable for the use or application by the Company of any of the Debt Securities or of the proceeds thereof. The Trustee shall not be charged with knowledge of any Default or Event of Default hereunder unless an officer of the Trustee assigned to and working in its corporate trust office shall have actual knowledge thereof or unless notice thereof shall have been given to the Trustee in accordance with Section 13.03 by the Company or any Holder.

Section 7.04 . Trustee, Paying Agent or Registrar May Own Debt Securities. The Trustee or any paying agent or Registrar, in its individual or any other capacity, may become the owner or pledgee of Debt Securities and subject to the provisions of the Trust Indenture Act relating to conflicts of interest and preferential claims may otherwise deal with the Company with the same rights it would have if it were not Trustee, paying agent or Registrar.

Section 7.05 . Moneys Received by Trustee to Be Held in Trust. Subject to the provisions of Section 11.05, all moneys received by the Trustee shall, until used or applied as herein provided, be held in trust for the purposes for which they were received, but need not be segregated from other funds except to the extent required by law. The Trustee shall be under no liability for interest on any moneys received by it hereunder. So long as no Event of Default shall have occurred and be continuing, all interest allowed on any such moneys shall be paid from time to time to the Company upon a Company Order.

Section 7.06 . Compensation and Reimbursement. The Company covenants and agrees to pay in Dollars to the Trustee from time to time, and the Trustee shall be entitled to, reasonable compensation for all services rendered by it hereunder (which shall not be limited by any provision of law in regard to the compensation of a trustee of an express trust), and, except as otherwise expressly provided herein, the Company will pay or reimburse in Dollars the Trustee upon its request for all reasonable expenses, disbursements and advances incurred or made by the Trustee in accordance with any of the provisions of this Indenture (including the reasonable compensation and the expenses and disbursements of its agents, attorneys and counsel and of all Persons not regularly in its employ) except any such expense, disbursement or advances as may arise from its negligence or bad faith. The Company also covenants to indemnify in Dollars the Trustee for, and to hold it harmless against, any loss, liability or expense Incurred without negligence, willful misconduct or bad faith on the part of the Trustee, arising out of or in connection with the acceptance or administration of the trust or trusts hereunder, including the reasonable costs and expenses of defending itself against any claim or liability in connection with the exercise or performance of any of its powers or duties hereunder. The obligations of the Company under this Section 7.06 to compensate and indemnify the Trustee and to pay or reimburse the Trustee for expenses, disbursements and advances shall constitute additional indebtedness hereunder and shall survive the satisfaction and discharge of this Indenture. The Company and the Holders agree that such additional indebtedness shall be secured by a Lien prior to that of the Debt Securities upon all property and funds held or collected by the Trustee, as such, except funds held in trust for the payment of principal of, and premium, if any, or interest on, particular Debt Securities.

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Without prejudice to any other rights available to the Trustee under applicable law, when the Trustee incurs expenses or renders services after an Event of Default specified in Section 6.01(g) or (h) occurs, the expenses and the compensation for the services are intended to constitute expenses of administration under any bankruptcy, insolvency, reorganization or other similar law.

Section 7.07 . Right of Trustee to Rely on an Officers’ Certificate Where No Other Evidence Specifically Prescribed. Except as otherwise provided in Section 7.01, whenever in the administration of the provisions of this Indenture the Trustee shall deem it necessary or desirable that a matter be proved or established prior to taking or suffering or omitting any action hereunder, such matter (unless other evidence in respect thereof be herein specifically prescribed) may, in the absence of negligence or bad faith on the part of the Trustee, be deemed to be conclusively proved and established by an Officers’ Certificate delivered to the Trustee and such certificate, in the absence of negligence or bad faith on the part of the Trustee, shall be full warrant to the Trustee for any action taken, suffered or omitted by it under the provisions of this Indenture upon the faith thereof.

Section 7.08 . Separate Trustee; Replacement of Trustee. The Company may, but need not, appoint a separate Trustee for any one or more series of Debt Securities. The Trustee may resign with respect to one or more or all series of Debt Securities at any time by giving notice to the Company. The Holders of a majority in principal amount of the Debt Securities of a particular series may remove the Trustee for such series and only such series by so notifying the Trustee and may appoint a successor Trustee. The Company shall remove the Trustee if:

(a) the Trustee fails to comply with Section 7.10;

(b) the Trustee is adjudged bankrupt or insolvent;

(c) a receiver or other public officer takes charge of the Trustee or its property; or

(d) the Trustee otherwise becomes incapable of acting.

If the Trustee resigns, is removed by the Company or by the Holders of a majority in principal amount of the Debt Securities of a particular series and (where so removed by such Holders) such Holders do not reasonably promptly appoint a successor Trustee, or if a vacancy exists in the office of Trustee for any reason (the Trustee in such event being referred to herein as the retiring Trustee),

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the Company shall promptly appoint a successor Trustee. No resignation or removal of the Trustee and no appointment of a successor Trustee shall become effective until the acceptance of appointment by the successor Trustee in accordance with the applicable requirements of this Section 7.08.

A successor Trustee shall deliver a written acceptance of its appointment to the retiring Trustee and to the Company. Thereupon the resignation or removal of the retiring Trustee shall become effective, and the successor Trustee shall have all the rights, powers and duties of the Trustee under this Indenture. The successor Trustee shall mail a notice of its succession to Holders of Debt Securities of each applicable series. The retiring Trustee shall promptly transfer all property held by it as Trustee to the successor Trustee, subject to the Lien provided for in Section 7.06.

If a successor Trustee does not take office within 60 days after the retiring Trustee gives notice of resignation or is removed, the retiring Trustee or the Holders of 25% in principal amount of the Debt Securities of any applicable series may petition any court of competent jurisdiction for the appointment of a successor Trustee for the Debt Securities of such series.

If the Trustee fails to comply with Section 7.10, any Holder of Debt Securities of any applicable series who has been a bona fide Holder of such Debt Securities for at least six months may petition any court of competent jurisdiction for the removal of the Trustee and the appointment of a successor Trustee for the Debt Securities of such series.

Notwithstanding the replacement of the Trustee pursuant to this Section 7.08, the Company’s obligations under Section 7.06 shall continue for the benefit of the retiring Trustee.

In the case of the appointment hereunder of a separate or successor trustee with respect to the Debt Securities of one or more but not all series, the Company, any retiring Trustee and each successor or separate Trustee with respect to the Debt Securities of any applicable series shall execute and deliver an Indenture supplemental hereto (1) which shall contain such provisions as shall be deemed necessary or desirable to confirm that all the rights, powers, trusts and duties of any retiring Trustee with respect to the Debt Securities of any series as to which any such retiring Trustee is not retiring shall continue to be vested in such retiring Trustee and (2) that shall add to or change any of the provisions of this Indenture as shall be necessary to provide for or facilitate the administration of the trusts hereunder by more than one trustee, it being understood that nothing herein or in such supplemental Indenture shall constitute such Trustees co-trustees of the same trust and that each such separate, retiring or successor Trustee shall be Trustee of a trust or trusts hereunder separate and apart from any trust or trusts hereunder administered by any other such Trustee.

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Section 7.09 . Successor Trustee by Merger. If the Trustee consolidates with, merges or converts into, or transfers all or substantially all of its corporate trust business or assets to, another corporation or banking association, the resulting, surviving or transferee corporation or banking association without any further act shall be the successor Trustee; provided , that it is qualified and eligible hereunder.

In case at the time such successor or successors by merger, conversion or consolidation to the Trustee shall succeed to the trusts created by this Indenture any of the Debt Securities shall have been authenticated but not delivered, any such successor to the Trustee may adopt the certificate of authentication of any predecessor trustee, and deliver such Debt Securities so authenticated; and in case at that time any of the Debt Securities shall not have been authenticated, any successor to the Trustee may authenticate such Debt Securities either in the name of any predecessor hereunder or in the name of the successor to the Trustee; and in all such cases such certificates shall have the full force which it is anywhere in the Debt Securities or in this Indenture provided that the certificate of the Trustee shall have.

Section 7.10 . Eligibility; Disqualification. The Trustee shall at all times satisfy the requirements of Section 310(a) of the Trust Indenture Act. The Trustee shall have a combined capital and surplus of at least $50,000,000, as set forth in its most recent published annual report of condition. No obligor upon the Debt Securities of a particular series or Person directly or indirectly controlling, controlled by or under common control with such obligor shall serve as Trustee upon the Debt Securities of such series. The Trustee shall comply with Section 310(b) of the Trust Indenture Act, subject to the penultimate paragraph thereof; provided , however , that there shall be excluded from the operation of Section 310(b)(1) of the Trust Indenture Act this Indenture or any indenture or indentures under which other securities or certificates of interest or participation in other securities of the Company are outstanding if the requirements for such exclusion set forth in Section 310(b)(1) of the Trust Indenture Act are met.

Section 7.11 . Preferential Collection of Claims Against Company. The Trustee shall comply with Section 311(a) of the Trust Indenture Act, excluding any creditor relationship listed in Section 311(b) of the Trust Indenture Act. A Trustee who had resigned or been removed shall be subject to Section 311(a) of the Trust Indenture Act to the extent indicated therein.

Section 7.12 . Compliance with Tax Laws. The Trustee hereby agrees to comply with all U.S. Federal income tax information reporting and withholding requirements applicable to it with respect to payments of premium (if any) and interest on the Debt Securities, whether acting as Trustee, Security Registrar, paying agent or otherwise with respect to the Debt Securities.

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ARTICLE 8

C ONCERNING THE H OLDERS

Section 8.01 . Evidence of Action by Holders. Whenever in this Indenture it is provided that the Holders of a specified percentage in aggregate principal amount of the Debt Securities of any or all series may take action (including the making of any demand or request, the giving of any direction, notice, consent or waiver or the taking of any other action) the fact that at the time of taking any such action the Holders of such specified percentage have joined therein may be evidenced (a) by any instrument or any number of instruments of similar tenor executed by Holders in person or by agent or proxy appointed in writing, (b) by the record of the Holders voting in favor thereof at any meeting of Holders duly called and held in accordance with the provisions of Section 13.09 or (c) by a combination of such instrument or instruments and any such record of such a meeting of Holders.

Section 8.02 . Proof of Execution of Instruments and of Holding of Debt Securities. Subject to the provisions of Sections 7.01, 7.02 and 13.09, proof of the execution of any instrument by a Holder or his agent or proxy shall be sufficient if made in accordance with such reasonable rules and regulations as may be prescribed by the Trustee or in such manner as shall be satisfactory to the Trustee.

The ownership of Registered Securities of any series shall be proved by the Debt Security Register or by a certificate of the Registrar for such series.

The Trustee may require such additional proof of any matter referred to in this Section 8.02 as it shall deem necessary.

Section 8.03 . Who May Be Deemed Owner of Debt Securities. Prior to due presentment for registration of transfer of any Registered Security, the Company, the Trustee, any paying agent and any Registrar may deem and treat the Person in whose name any Registered Security shall be registered upon the books of the Company as the absolute owner of such Registered Security (whether or not such Registered Security shall be overdue and notwithstanding any notation of ownership or other writing thereon) for the purpose of receiving payment of or on account of the principal of and premium, if any, and (subject to Sections 2.12 and 2.17) interest on such Registered Security and for all other purposes, and neither the Company nor the Trustee nor any paying agent nor any Registrar shall be affected by any notice to the contrary; and all such payments so made to any such Holder for the time being, or upon his order, shall be valid and, to the extent of the sum or sums so paid, effectual to satisfy and discharge the liability for moneys payable upon any such Registered Security.

None of the Company, the Trustee, any paying agent or the Registrar will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in a Global Security or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

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Section 8.04 . Instruments Executed by Holders Bind Future Holders. At any time prior to (but not after) the evidencing to the Trustee, as provided in Section 8.01, of the taking of any action by the Holders of the percentage in aggregate principal amount of the Debt Securities of any series specified in this Indenture in connection with such action and subject to the following paragraph, any Holder of a Debt Security which is shown by the evidence to be included in the Debt Securities the Holders of which have consented to such action may, by filing written notice with the Trustee at its corporate trust office and upon proof of holding as provided in Section 8.02, revoke such action so far as concerns such Debt Security. Except as aforesaid any such action taken by the Holder of any Debt Security shall be conclusive and binding upon such Holder and upon all future Holders and owners of such Debt Security and of any Debt Security issued upon registration of transfer thereof or in exchange or substitution therefor, irrespective of whether or not any notation in regard thereto is made upon such Debt Security or such other Debt Securities. Any action taken by the Holders of the percentage in aggregate principal amount of the Debt Securities of any series specified in this Indenture in connection with such action shall be conclusively binding upon the Company, the Trustee and the Holders of all the Debt Securities of such series.

The Company may, but shall not be obligated to, fix a record date for the purpose of determining the Holders of Registered Securities entitled to give their consent or take any other action required or permitted to be taken pursuant to this Indenture. If a record date is fixed, then notwithstanding the immediately preceding paragraph, those Persons who were Holders of Registered Securities at such record date (or their duly designated proxies), and only those Persons, shall be entitled to give such consent or to revoke any consent previously given or to take any such action, whether or not such Persons continue to be Holders of Registered Securities after such record date. No such consent shall be valid or effective for more than 120 days after such record date unless the consent of the Holders of the percentage in aggregate principal amount of the Debt Securities of such series specified in this Indenture shall have been received within such 120-day period.

ARTICLE 9

S UPPLEMENTAL I NDENTURES

Section 9.01 . Purposes for Which Supplemental Indenture May Be Entered into Without Consent of Holders. The Company, when authorized by a resolution of the Board of Directors, and the Trustee may from time to time and at any time, without the consent of Holders, enter into an Indenture or Indentures supplemental hereto (which shall conform to the provisions of the Trust Indenture Act as in force at the date of the execution thereof) for one or more of the following purposes:

(a) to evidence the succession pursuant to Article 10 of another Person to the Company, or successive successions, and the assumption by the Successor Company (as defined in Section 10.01) of the covenants, agreements and obligations of the Company in this Indenture and in the Debt Securities;

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(b) to surrender any right or power herein conferred upon the Company, to add to the covenants of the Company such further covenants, restrictions, conditions or provisions for the protection of the Holders of all or any series of Debt Securities (and if such covenants are to be for the benefit of less than all series of Debt Securities, stating that such covenants are expressly being included solely for the benefit of such series) as the Board of Directors shall consider to be for the protection of the Holders of such Debt Securities, and to make the occurrence, or the occurrence and continuance, of a default in any of such additional covenants, restrictions, conditions or provisions a Default or an Event of Default permitting the enforcement of all or any of the several remedies provided in this Indenture; provided , that in respect of any such additional covenant, restriction, condition or provision such supplemental Indenture may provide for a particular period of grace after Default (which period may be shorter or longer than that allowed in the case of other Defaults) or may provide for an immediate enforcement upon such Default or may limit the remedies available to the Trustee upon such Default or may limit the right of the Holders of a majority in aggregate principal amount of any or all series of Debt Securities to waive such default;

(c) to cure any ambiguity or to correct or supplement any provision contained herein, in any supplemental Indenture or in any Debt Securities of any series that may be defective or inconsistent with any other provision contained herein, in any supplemental Indenture or in the Debt Securities of such series; to convey, transfer, assign, mortgage or pledge any property to or with the Trustee, or to make such other provisions in regard to matters or questions arising under this Indenture as shall not adversely affect the interests of any Holders of Debt Securities of any series;

(d) to modify or amend this Indenture in such a manner as to permit the qualification of this Indenture or any Indenture supplemental hereto under the Trust Indenture Act as then in effect, except that nothing herein contained shall permit or authorize the inclusion in any Indenture supplemental hereto of the provisions referred to in Section 316(a)(2) of the Trust Indenture Act;

(e) to add to or change any of the provisions of this Indenture to change or eliminate any restrictions on the payment of principal of, or premium, if any, or interest on, Registered Securities; provided , that any such action shall not adversely affect the interests of the Holders of Debt Securities of any series in any material respect; or permit or facilitate the issuance of Debt Securities of any series in uncertificated form;

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(f) in the case of any Debt Securities, if any, subordinated pursuant to Article 12, to make any change in Article 12 that would limit or terminate the benefits applicable to any holder of Senior Indebtedness (or Representatives therefor) under Article 12;

(g) to add Guarantees with respect to the Debt Securities or to secure the Debt Securities;

(h) to add to, change or eliminate any of the provisions of this Indenture in respect of one or more series of Debt Securities; provided , however , that any such addition, change or elimination not otherwise permitted under this Section 9.01 shall (i) neither (A) apply to any Debt Security of any series created prior to the execution of such supplemental Indenture and entitled to the benefit of such provision nor (B) modify the rights of the Holder of any such Debt Security with respect to such provision or (ii) shall become effective only when there is no such Debt Security outstanding;

(i) to evidence and provide for the acceptance of appointment hereunder by a successor or separate Trustee with respect to the Debt Securities of one or more series and to add to or change any of the provisions of this Indenture as shall be necessary to provide for or facilitate the administration of the trusts hereunder by more than one Trustee; and

(j) to establish the form or terms of Debt Securities of any series as permitted by Sections 2.01 and 2.03.

The Trustee is hereby authorized to join with the Company in the execution of any such supplemental Indenture, to make any further appropriate agreements and stipulations which may be therein contained and to accept the conveyance, transfer, assignment, mortgage or pledge of any property thereunder, but the Trustee shall not be obligated to enter into any such supplemental Indenture which affects the Trustee’s own rights, duties or immunities under this Indenture or otherwise.

Any supplemental Indenture authorized by the provisions of this Section 9.01 may be executed by the Company and the Trustee without the consent of the Holders of any of the Debt Securities at the time outstanding, notwithstanding any of the provisions of Section 9.02.

In the case of any Debt Securities subordinated pursuant to Article 12, an amendment under this Section 9.01 may not make any change that adversely affects the rights under Article 12 of any holder of Senior Indebtedness then outstanding unless the holders of such Senior Indebtedness (or any group or Representative thereof authorized to give a consent) consent to such change.

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After an amendment under this Section 9.01 becomes effective, the Company shall mail to Holders of Debt Securities of each series affected thereby a notice briefly describing such amendment. The failure to give such notice to all such Holders, or any defect therein, shall not impair or affect the validity of an amendment under this Section 9.01.

Section 9.02. Modification of Indenture with Consent of Holders of Debt Securities . Without notice to any Holder but with the consent (evidenced as provided in Section 8.01) of the Holders of not less than a majority in aggregate principal amount of the outstanding Debt Securities of each series affected by such supplemental Indenture, the Company, when authorized by a resolution of the Board of Directors, and the Trustee may from time to time and at any time enter into an Indenture or Indentures supplemental hereto (which shall conform to the provisions of the Trust Indenture Act as in force at the date of execution thereof) for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of this Indenture or of any supplemental Indenture or of modifying in any manner the rights of the Holders of the Debt Securities of such series; provided, that no such supplemental Indenture, without the consent of the Holders of each Debt Security so affected, shall:

(a) reduce the principal amount of, the rate of interest on, or the premium, if any, payable upon the redemption or repurchase of, the Debt Securities;

(b) change the Stated Maturity of, or any installment of principal of, or interest on, the Debt Securities;

(c) change the time at which any Debt Securities may be redeemed or repurchased;

(d) change the place or currency of payment of principal of, or premium, if any, or interest on the Debt Securities;

(e) impair the right to institute suit for the enforcement of any payment on or with respect to the Debt Securities on or after the Stated Maturity or prepayment date thereof;

(f) reduce the percentage in principal amount of the Debt Securities required for modification or amendment of the Indenture or the Debt Securities or for waiver of compliance with certain provisions of the Indenture or the Debt Securities or for waiver of certain defaults; or

(g) modify or release any security that may have been granted in respect of the Debt Securities in any manner adverse to the holders of the Debt Securities.

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A supplemental Indenture which changes or eliminates any covenant or other provision of this Indenture which has been expressly included solely for the benefit of one or more particular series of Debt Securities or which modifies the rights of the Holders of Debt Securities of such series with respect to such covenant or other provision, shall be deemed not to affect the rights under this Indenture of the Holders of Debt Securities of any other series.

Upon the request of the Company, accompanied by a copy of a resolution of the Board of Directors authorizing the execution of any such supplemental Indenture, and upon the filing with the Trustee of evidence of the consent of Holders as aforesaid, the Trustee shall join with the Company in the execution of such supplemental Indenture unless such supplemental Indenture affects the Trustee’s own rights, duties or immunities under this Indenture or otherwise, in which case the Trustee may in its discretion but shall not be obligated to enter into such supplemental Indenture.

It shall not be necessary for the consent of the Holders under this Section 9.02 to approve the particular form of any proposed supplemental Indenture, but it shall be sufficient if such consent shall approve the substance thereof.

In the case of any Debt Securities subordinated pursuant to Article 12, an amendment under this Section 9.02 may not make any change that adversely affects the rights under Article 12 of any holder of Senior Indebtedness then outstanding unless the holders of such Senior Indebtedness (or any group or Representative thereof authorized to give a consent) consent to such change.

After an amendment under this Section 9.02 becomes effective, the Company shall mail to Holders of Debt Securities of each series affected thereby a notice briefly describing such amendment. The failure to give such notice to all such Holders, or any defect therein, shall not impair or affect the validity of an amendment under this Section 9.02.

Section 9.03 . Effect of Supplemental Indentures. Upon the execution of any supplemental Indenture pursuant to the provisions of this Article 9, this Indenture shall be and be deemed to be modified and amended in accordance therewith and the respective rights, limitations of rights, obligations, duties and immunities under this Indenture of the Trustee, the Company and the Holders shall thereafter be determined, exercised and enforced hereunder subject in all respects to such modifications and amendments, and all the terms and conditions of any such supplemental Indenture shall be and be deemed to be part of the terms and conditions of this Indenture for any and all purposes.

The Trustee, subject to the provisions of Sections 7.01 and 7.02, may receive an Officers’ Certificate and an Opinion of Counsel as conclusive evidence that any such supplemental Indenture complies with the provisions of this Article 9.

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Section 9.04 . Debt Securities May Bear Notation of Changes by Supplemental Indentures. Debt Securities of any series authenticated and delivered after the execution of any supplemental Indenture pursuant to the provisions of this Article 9 may, and shall if required by the Trustee, bear a notation in form approved by the Trustee as to any matter provided for in such supplemental Indenture. New Debt Securities of any series so modified as to conform, in the opinion of the Trustee and the Board of Directors, to any modification of this Indenture contained in any such supplemental Indenture may be prepared and executed by the Company, authenticated by the Trustee and delivered in exchange for the Debt Securities of such series then outstanding. Failure to make the appropriate notation or to issue a new Debt Security of such series shall not affect the validity of such amendment.

Section 9.05 . Payment for Consent. Neither the Company nor any Affiliate of the Company shall, directly or indirectly, pay or cause to be paid any consideration, whether by way of interest fee or otherwise, to any Holder for or as an inducement to any consent, waiver or amendment of any of the terms or provisions of this Indenture or the Debt Securities unless such consideration is offered to be paid to all Holders that so consent, waive or agree to amend in the time frame set forth in solicitation documents relating to such consent, waiver or agreement.

ARTICLE 10

C ONSOLIDATION , M ERGER , S ALE OR C ONVEYANCE

Section 10.01 . Consolidations and Mergers of the Company. The Company shall not consolidate with or merge with or into any Person, or convey, transfer or lease all or substantially all its assets to any Person, unless: (i) either (a) the Company shall be the continuing Person in the case of a merger or (b) the resulting, surviving or transferee Person if other than the Company (the “ Successor Company ”) shall be a corporation organized and existing under the laws of the United States, any State thereof or the District of Columbia and the Successor Company shall expressly assume, by an Indenture supplemental hereto, executed and delivered to the Trustee, in form satisfactory to the Trustee, all the obligations of the Company under the Debt Securities according to their tenor, and this Indenture; (ii) immediately after giving effect to such transaction (and treating any Indebtedness which becomes an obligation of the Successor Company or any Subsidiary of the Company as a result of such transaction as having been Incurred by the Successor Company or such Subsidiary at the time of such transaction), no Default or Event of Default would occur or be continuing; and (iii) the Company shall have delivered to the Trustee an Officers’ Certificate and an Opinion of Counsel, each stating that such consolidation, merger, conveyance, transfer or lease and such supplemental Indenture (if any) comply with this Indenture.

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Section 10.02 . Rights and Duties of Successor Corporation. In case of any consolidation, merger, conveyance, transfer or lease of the assets of the Company in accordance with Section 10.01, the Successor Company shall succeed to and be substituted for the Company, with the same effect as if it had been named herein as the party of the first part, and the predecessor corporation (except in the case of a lease) shall be relieved of any further obligation under the Indenture and the Debt Securities. The Successor Company thereupon may cause to be signed, and may issue either in its own name or in the name of the Company, any or all the Debt Securities issuable hereunder which theretofore shall not have been signed by the Company and delivered to the Trustee; and, upon the order of the Successor Company, instead of the Company, and subject to all the terms, conditions and limitations in this Indenture prescribed, the Trustee shall authenticate and shall deliver any Debt Securities which previously shall have been signed and delivered by the officers of the Company to the Trustee for authentication, and any Debt Securities which the Successor Company thereafter shall cause to be signed and delivered to the Trustee for that purpose. All the Debt Securities so issued shall in all respects have the same legal rank and benefit under this Indenture as the Debt Securities theretofore or thereafter issued in accordance with the terms of this Indenture as though all such Debt Securities had been issued at the date of the execution hereof.

In case of any such consolidation, merger, conveyance, transfer or lease, such changes in phraseology and form (but not in substance) may be made in the Debt Securities appertaining thereto thereafter to be issued as may be appropriate.

ARTICLE 11

S ATISFACTION AND D ISCHARGE OF I NDENTURE ; D EFEASANCE AND C OVENANT D EFEASANCE ; U NCLAIMED M ONEYS

Section 11.01 . Company’s Option to Effect Defeasance or Covenant Defeasance. The Company may elect, at its option by resolution of the Company’s Board of Directors at any time, to have either Section 11.02 or Section 11.03 applied to the Outstanding Debt Securities of any series designated pursuant to Section 2.03 as being defeasible pursuant to this Article 11 (hereinafter called “ Defeasible Series ”), upon compliance with the conditions set forth below in this Article 11, provided that Section 11.02 will not apply to any series of Debt Securities that is convertible into Common Stock or convertible into or exchangeable for any other securities pursuant to Section 2.03(h).

Section 11.02 . Defeasance and Discharge.

Upon the Company’s exercise of the option provided in Section 11.01 to have this Section 11.02 applied to the Outstanding Debt Securities of any Defeasible Series and subject to the proviso to Section 11.01, the Company will be deemed to have been discharged from its obligations with respect to the Outstanding Debt Securities of such series as provided in this Section 11.02, and all obligations of any subsidiary guarantors, as applicable, will be deemed to have

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been discharged with respect to the Outstanding Debt Securities of such series and the applicable guarantees, on and after the date the conditions set forth in Section 11.04 are satisfied (hereinafter called “ Defeasance ”). For this purpose, such Defeasance means that the Company and the subsidiary guarantors, as applicable, will be deemed to have paid and discharged the entire indebtedness represented by the Outstanding Debt Securities of such series and to have satisfied all its other obligations under the Debt Securities of such series, any applicable guarantees, and this Indenture insofar as the Debt Securities of such series are concerned (and the Trustee, at the expense of the Company, will execute proper instruments acknowledging the same), subject to the following which will survive until otherwise terminated or discharged hereunder:

(a) the rights of Holders of Debt Securities of such series to receive, solely from the trust fund described in Section 11.04 and as more fully set forth in Section 11.04, payments in respect of the principal of and any premium and interest on such Debt Securities of such series when payments are due,

(b) the Company’s obligations with respect to the Debt Securities of such series under Sections 2.07, 2.08, 2.09, 4.02, 4.04, and 9.04,

(c) the rights, powers, trusts, duties, and immunities of the Trustee hereunder, and

(d) this Article 11.

Subject to compliance with this Article 11, the Company may exercise its option provided in Section 11.01 to have this Section 11.02 applied to the Outstanding Debt Securities of any Defeasible Series notwithstanding the prior exercise of its option provided in Section 11.01 to have Section 11.03 applied to the Outstanding Debt Securities of such series.

Section 11.03 . Covenant Defeasance. Upon the Company’s exercise of the option provided in Section 11.01 to have this Section 11.03 applied to the Outstanding Debt Securities of any Defeasible Series, (a) the Company and the subsidiary guarantors, as applicable, will be released from their obligations under Section 4.07, Section 10.01, and the provisions of any indenture supplemental hereto specified in such supplemental indenture, and (b) the occurrence of any event specified in Sections 6.01(c), 6.01(e) (with respect to Section 4.07, Section 10.01, and the provisions of any indenture supplemental hereto specified in such supplemental indenture), 6.01(f), 6.01(g) and 6.01(h) (only as Sections 6.01(g) or 6.01(h) apply to any Significant Subsidiary) and 6.01(i) (and any similar, corresponding or overriding events of default provided for in any indenture supplemental hereto) will be deemed not to be or result in an Event of Default, in each case with respect to the Outstanding Debt Securities of such series as provided in this Section on and after the date the conditions set forth in Section 11.04 are satisfied (hereinafter called “ Covenant Defeasance ”). For this purpose, such Covenant Defeasance means that the Company and the subsidiary

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guarantors, as applicable, may omit to comply with and will have no liability in respect of any term, condition, or limitation set forth in any such specified Section (to the extent specified above in the case of Section 6.01(e) or in any such specified provision of such supplemental indenture), whether directly or indirectly by reason of any reference elsewhere herein to any such Section or provision or by reason of any reference in any such Section or provision to any other provision herein or in any other document, but the remainder of this Indenture and the Debt Securities of such series will be unaffected thereby.

Section 11.04 . Conditions to Defeasance or Covenant Defeasance. The following will be the conditions to application of either Section 11.02 or Section 11.03 to the Outstanding Debt Securities of any Defeasible Series:

(a) The Company shall irrevocably have deposited or caused to be deposited with the Trustee (or another trustee that satisfies the requirements contemplated by Section 7.10 and agrees to comply with the provisions of this Article 11 applicable to it) as trust funds in trust for the benefit of the Holders of Outstanding Debt Securities of such series (i) money in an amount, or (ii) U.S. Government Obligations that through the scheduled payment of principal and interest in respect thereof in accordance with their terms will provide, without reinvestment, not later than one day before the due date of any payment, money in an amount, or (iii) a combination thereof, in each case sufficient to pay and discharge, and which will be applied by the Trustee (or any such other qualifying trustee) to pay and discharge, the principal of and any premium and interest on the Debt Securities of such series on the respective Stated Maturities or on any earlier date or dates on which the Debt Securities of such series shall be subject to redemption and the Company shall have given the Trustee irrevocable instructions satisfactory to the Trustee to give notice to the Holders of the redemption of the Debt Securities of such series, all in accordance with the terms of this Indenture and the Debt Securities of such series.

(b) In the case of an election under Section 11.02, the Company shall have delivered to the Trustee an Opinion of Counsel (from a counsel who shall not be an employee of the Company) to the effect that (i) the Company has received from, or there has been published by, the Internal Revenue Service a ruling, or (ii) since the date of this Indenture there has been a change in the applicable federal income tax law, in either case to the effect that, and based thereon, such opinion shall confirm that, the Holders of the Outstanding Debt Securities of such series will not recognize gain or loss for federal income tax purposes as a result of the deposit, Defeasance, and discharge to be effected with respect to the Debt Securities of such series and will be subject to federal income tax on the same amount, in the same manner, and at the same times as would be the case if such deposit, Defeasance, and discharge were not to occur.

(c) In the case of an election under Section 11.03, the Company shall have delivered to the Trustee an Opinion of Counsel (from a counsel who shall not be an employee of the Company) to the effect that the Holders of the

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Outstanding Debt Securities of such series will not recognize gain or loss for federal income tax purposes as a result of the deposit and Covenant Defeasance to be effected with respect to the Debt Securities of such series and will be subject to federal income tax on the same amount, in the same manner, and at the same times as would be the case if such deposit and Covenant Defeasance were not to occur.

(d) The Company shall have delivered to the Trustee an Officer’s Certificate to the effect that the Debt Securities of such series, if then listed on any securities exchange, will not be delisted solely as a result of such deposit.

(e) No Event of Default or event that (after notice or lapse of time or both) would become an Event of Default shall have occurred and be continuing at the time of such deposit or, with regard to any Event of Default or any such event specified in Sections 6.01(g) and 6.01(h), at any time on or prior to the 90th calendar day after the date of such deposit (it being understood that this condition will not be deemed satisfied until after such 90th calendar day).

(f) Such Defeasance or Covenant Defeasance will not cause the Trustee to have a conflicting interest within the meaning of the Trust Indenture Act (assuming all Debt Securities are in default within the meaning of such Act).

(g) Such Defeasance or Covenant Defeasance will not result in a breach or violation of, or constitute a default under, any other agreement or instrument to which the Company is a party or by which it is bound.

(h) The Company shall have delivered to the Trustee a certificate from a nationally recognized firm of independent accountants or other Person acceptable to the Trustee expressing their opinion that the payments of principal and interest when due and without reinvestment on the deposited U.S. Government Obligations plus any deposited money without investment will provide the cash at such times and in such amounts as will be sufficient to pay the principal of and any premium and interest when due on the Debt Securities of such series on the respective Stated Maturities or on any earlier date or dates on which the Debt Securities of such series shall be subject to redemption.

(i) The Company shall have delivered to the Trustee an Officer’s Certificate and an Opinion of Counsel, each stating that all conditions precedent with respect to such Defeasance or Covenant Defeasance have been complied with.

(j) Such Defeasance or Covenant Defeasance will not result in the trust arising from such deposit constituting an investment company within the meaning of the Investment Company Act of 1940, as amended, unless such trust will be qualified under such Act or will be exempt from regulation thereunder.

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Section 11.05 . Deposited Money and U.S. Government Obligations to be Held in Trust; Other Miscellaneous Provisions.

(a) Subject to the provisions of Section 4.04, all money and U.S. Government Obligations (including the proceeds thereof) deposited with the Trustee or other qualifying trustee (solely for purposes of this Section 11.05 and Section 11.06, the Trustee and any such other trustee are referred to collectively as the “ Trustee ”) pursuant to Section 11.04 in respect of the Debt Securities of any Defeasible Series will be held in trust and applied by the Trustee, in accordance with the provisions of the Debt Securities of such series and this Indenture, to the payment, either directly or through any such paying agent (including the Company acting as its own paying agent) as the Trustee may determine, to the Holders of Debt Securities of such series, of all sums due and to become due thereon in respect of principal and any premium and interest, but money so held in trust need not be segregated from other funds except to the extent required by law.

(b) The Company will pay and indemnify the Trustee against any tax, fee, or other charge imposed on or assessed against the U.S. Government Obligations deposited pursuant to Section 11.04 or the principal and interest received in respect thereof other than any such tax, fee, or other charge that by law is for the account of the Holders of Outstanding Debt Securities.

(c) Notwithstanding anything in this Article 11 to the contrary, the Trustee will deliver or pay to the Company from time to time upon a Company Order any money or U.S. Government Obligations held by it as provided in Section 11.04 with respect to Debt Securities of any Defeasible Series that are in excess of the amount thereof that would then be required to be deposited to effect an equivalent Defeasance or Covenant Defeasance with respect to the Debt Securities of such series.

Section 11.06 . Indemnity for U.S. Government Obligations. The Company shall pay and shall indemnify the Trustee and the Holders against any tax, fee or other charge imposed on or assessed against deposited U.S. Government Obligations or the principal and interest received on such U.S. Government Obligations.

Section 11.07 . Reinstatement. If the Trustee or any paying agent is unable to apply any money in accordance with this Article 11 with respect to the Debt Securities of any series by reason of any order or judgment of any court or governmental authority enjoining, restraining, or otherwise prohibiting such application, then the Company’s obligations under this Indenture and the Debt Securities of such series will be revived and reinstated as though no deposit had occurred pursuant to this Article 11 with respect to Debt Securities of such series until such time as the Trustee or any paying agent is permitted to apply all money held in trust pursuant to Section 11.05 with respect to Debt Securities of such series in accordance with this Article 11; provided, however, that if the Company

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makes any payment of principal of or any premium or interest on any Security of such series following the reinstatement of its obligations, the Company will be subrogated to the rights of the Holders of Debt Securities of such series to receive such payment from the money so held in trust.

Section 11.08. Satisfaction and Discharge of Indenture.

This Indenture will upon a Company Order cease to be of further effect (except as to any surviving rights of registration of transfer or exchange of Debt Securities herein expressly provided for), and the Trustee, at the expense the Company, will execute proper instruments acknowledging satisfaction and discharge of this Indenture, when:

(a) either (i) all Debt Securities theretofore authenticated and delivered (other than (A) Debt Securities which have been destroyed, lost, or stolen and which have been replaced or paid as provided in Section 2.09 and (B) Debt Securities for the payment of which money has theretofore been deposited in trust or segregated and held in trust by the Company and thereafter repaid to the Company or discharged from such trust, as provided in Section 4.04) have been delivered to the Trustee for cancellation or (ii) all such Debt Securities not theretofore delivered to the Trustee for cancellation (A) have become due and payable, (B) will become due and payable at their Stated Maturity within one year, or (C) are to be called for redemption within one year under arrangements satisfactory to the Trustee for the giving of notice of redemption by the Trustee in the name, and at the expense, of the Company, and the Company, in the case of clause (A), (B), or (C) above, has deposited or caused to be deposited with the Trustee as trust funds in trust for such purpose an amount sufficient to pay and discharge the entire indebtedness on such Debt Securities not theretofore delivered to the Trustee for cancellation, for principal and any premium and interest to the date of such deposit (in the case of Debt Securities which have become due and payable) or to the Stated Maturity or Redemption Date, as the case may be;

(b) the Company has paid or caused to be paid all other sums payable hereunder by the Company; and

(c) the Company has delivered to the Trustee an Officer’s Certificate and an Opinion of Counsel, each stating that all conditions precedent herein provided for relating to the satisfaction and discharge of this Indenture have been satisfied. Notwithstanding the satisfaction and discharge of this Indenture, the obligations of the Company to the Trustee under Section 7.06, and, if money shall have been deposited with the Trustee pursuant to subclause (ii) of clause (a) of this Section 11.01, the obligations of the Trustee under Sections 4.04 and 11.09, will survive.

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Section 11.09. Application of Trust Money. Subject to the provisions of Section 4.04, all money deposited with the Trustee pursuant to Section 11.08 will be held in trust and applied by it, in accordance with the provisions of the Debt Securities and this Indenture, to the payment, either directly or through any paying agent (including the Company acting as its own paying agent) as the Trustee may determine, to the Persons entitled thereto, of the principal and any premium and interest for the payment of which such money has been deposited with the Trustee; and such money shall be segregated from other funds to the extent required by law.

ARTICLE 12

S UBORDINATION OF D EBT S ECURITIES

Section 12.01 . Agreement to Subordinate. The Company agrees, and each Holder by accepting Debt Securities agrees, that the payment of principal, premium, if any, and interest on, and other Indebtedness evidenced by, the Debt Securities is subordinated in right of payment, to the extent and in the manner provided in this Article 12, to the prior payment in full of all Senior Indebtedness (whether outstanding on the date hereof or hereafter incurred) of the Company, will rank equally in right of payment with all existing and future Senior Subordinated Indebtedness of the Company and will be senior in right of payment to all existing and future Subordinated Obligations of the Company, and that the subordination is for the benefit of the holders of Senior Indebtedness.

Section 12.02 . Liquidation, Dissolution, Bankruptcy. In the event of:

(a) a total or partial liquidation or a dissolution of the Company;

(b) a reorganization, bankruptcy, insolvency, receivership of or similar proceeding relating to the Company or its property; or

(c) an assignment for the benefit of creditors or marshaling of the Company’s assets and liabilities, then

the holders of Senior Indebtedness will be entitled to receive payment in full in cash or Cash Equivalents in respect of Senior Indebtedness (including interest accruing after, or which would accrue but for, the commencement of any proceeding at the rate specified in the applicable Senior Indebtedness, whether or not a claim for such interest would be allowed in such proceeding) before the Holders of Debt Securities will be entitled to receive any payment or distribution, in the event of any payment or distribution of the assets or securities of the Company. In addition, until the Senior Indebtedness is paid in full in cash or Cash Equivalents, any payment or distribution to which holders of Debt Securities would be entitled but for the subordination provisions of the Indenture will be made to holders of the Senior Indebtedness as their interests may appear. If a payment or distribution is made to Holders of Debt Securities that, due to the subordination provisions, should not have been made to them, the Holders shall hold it in trust for the holders of Senior Indebtedness and pay the payment or distribution over to holders of Senior Indebtedness, as their interests may appear.

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Section 12.03 . Default on Senior Indebtedness. The Company may not pay principal of, premium, if any, or interest on, or other payment obligations in respect of, Debt Securities or make any deposit and may not otherwise repurchase, redeem or retire any Debt Securities (collectively, “ pay the Debt Securities ”) if:

(a) any Senior Indebtedness is not paid when due in cash or Cash Equivalents; or

(b) any other default on Senior Indebtedness occurs and is continuing with respect to Senior Indebtedness and the maturity of the Senior Indebtedness is accelerated in accordance with its terms;

unless, in either case, the Senior Indebtedness has been paid in full in cash or Cash Equivalents and, in the case of revolving Indebtedness, all commitments to lend thereunder have been terminated or the default has been cured or waived and any acceleration has been rescinded. However, the Company may pay the Debt Securities if the Company and the Trustee receive written notice approving such payment from the Representative of the Senior Indebtedness with respect to which either of the events set forth in clause (a) or (b) of the immediately preceding sentence has occurred and is continuing.

The Company also will not be permitted to pay the Debt Securities for a Payment Blockage Period (as defined below) during the continuance of any default, other than a default described in clause (a) or (b) of the preceding paragraph, on any Designated Senior Indebtedness that permits the holders of the Designated Senior Indebtedness to accelerate its maturity immediately without either further notice (except such notice as may be required to effect such acceleration) or the expiration of any applicable grace periods.

A “ Payment Blockage Period ” commences on the receipt by the Trustee (with a copy to the Company) of written notice (a “ Blockage Notice ”) of a default of the kind described in the immediately preceding paragraph from the Representative of the holders of the Designated Senior Indebtedness specifying an election to effect a Payment Blockage Period and ends 179 days after receipt of the notice. The Payment Blockage Period will end earlier if the Payment Blockage Period is terminated:

(a) by written notice to the Trustee and the Company from the Person or Persons who gave the Blockage Notice;

(b) because the default giving rise to the Blockage Notice is no longer continuing; or

(c) because the Designated Senior Indebtedness has been repaid in full.

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The Company may resume payments on the Debt Securities after the end of a Payment Blockage Period (including any missed payments) unless the holders of the Designated Senior Indebtedness or the Representatives of such holders have accelerated the maturity of the Designated Senior Indebtedness. Not more than one Blockage Notice may be given in any consecutive 360-day period, irrespective of the number of defaults with respect to Designated Senior Indebtedness during that period. However, if any Blockage Notice within such 360-day period is given by or on behalf of any holders of Designated Senior Indebtedness other than the Bank Indebtedness, the Representatives of the Bank Indebtedness may give another Blockage Notice within that period. In no event, however, may the total number of days during which any Payment Blockage Period or Periods is in effect exceed 179 days in the aggregate during any consecutive 360-day period. No Default or Event of Default that existed or was continuing on the date of the commencement of any Payment Blockage Period with respect to the Designated Senior Indebtedness initiating the Payment Blockage Period shall be, or be made, the basis of the commencement of a subsequent Payment Blockage Period by the Representative of the Designated Senior Indebtedness, whether or not within a period of 360 consecutive days, unless such Default or Event of Default shall have been cured or waived for a period of not less than 90 consecutive days.

Section 12.04 . Acceleration of Payment of Debt Securities. The Company or the Trustee shall promptly notify holders of Designated Senior Indebtedness if payment of the Debt Securities is accelerated because of an Event of Default.

Section 12.05 . When Distribution Must Be Paid Over. In the event that the Trustee or any Holder receives any payment of any Indebtedness with respect to the Debt Securities at a time when the Trustee or such Holder, as applicable, has actual knowledge that such payment is prohibited by Section 12.03 hereof, such payment shall be held by the Trustee or such Holder, in trust for the benefit of and, upon written request, shall be paid forthwith over and delivered to, the holders of Senior Indebtedness as their interests may appear or their Representative under the indenture or other agreement (if any) pursuant to which Senior Indebtedness may have been issued, as their respective interests may appear, for application to the payment of all obligations with respect to Senior Indebtedness remaining unpaid to the extent necessary to pay such obligations in full in accordance with their terms, after giving effect to any concurrent payment or distribution to or for the holders of Senior Indebtedness.

With respect to the holders of Senior Indebtedness, the Trustee undertakes to perform only such obligations on the part of the Trustee as are specifically set forth in this Article 12, and no implied covenants or obligations with respect to the holders of Senior Indebtedness shall be read into this Indenture against the Trustee. The Trustee shall not be deemed to owe any fiduciary duty to the holders of Senior Indebtedness, and shall not be liable to any such holders if the Trustee shall pay over or distribute to or on behalf of Holders or the Company or any other Person money or assets to which any holders of Senior Indebtedness shall be entitled by virtue of this Article 12, except if such payment is made as a result of the willful misconduct or gross negligence of the Trustee.

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Section 12.06 . Notice by the Company. The Company shall promptly notify the Trustee and any paying agent of any facts known to the Company that would cause a payment of any Indebtedness with respect to the Debt Securities to violate this Article 12, but failure to give such notice shall not affect the subordination of the Debt Securities to the Senior Indebtedness as provided in this Article.

The Company may not pay the Debt Securities until five business days after such holders or the Representative of the Designated Senior Indebtedness receives notice of such acceleration and, after that five business day period, may pay the Debt Securities only if this Article 12 otherwise permits payment at that time.

Section 12.07 . Subrogation. After all Senior Indebtedness is irrevocably paid in full in cash or Cash Equivalents reasonably satisfactory to the holders thereof and until the Debt Securities are paid in full, Holders shall be subrogated (equally and ratably with all other Senior Subordinated Indebtedness pari passu with the Debt Securities) to the rights of holders of Senior Indebtedness to receive distributions applicable to Senior Indebtedness to the extent that distributions otherwise payable to the Holders have been applied to the payment of Senior Indebtedness. A distribution made under this Article 12 to holders of Senior Indebtedness that otherwise would have been made to Holders is not, as between the Company and Holders, a payment by the Company on the Debt Securities.

Section 12.08 . Relative Rights. This Article 12 defines the relative rights of Holders and holders of Senior Indebtedness. Nothing in this Indenture shall:

(a) impair, as between the Company and Holders, the obligation of the Company, which is absolute and unconditional, to pay principal of and interest on the Debt Securities in accordance with their terms;

(b) affect the relative rights of Holders and other creditors of the Company other than their rights in relation to holders of Senior Indebtedness; or

(c) prevent the Trustee or any Holder from exercising its available remedies upon a Default or Event of Default, subject to the rights of holders and owners of Senior Debt to receive distributions and payments otherwise payable to Holders.

If the Company fails because of this Article 12 to pay principal of or interest on Debt Securities on the due date, the failure is still a Default or Event of Default.

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Section 12.09 . Subordination May Not Be Impaired by Company. No right of any holder of Senior Indebtedness to enforce the subordination of the Indebtedness evidenced by the Debt Securities shall be impaired by any act or failure to act by the Company or any Holder or by the failure of the Company or any Holder to comply with this Indenture.

Section 12.10. Distribution or Notice to Representative. Whenever a distribution is to be made or a notice given to holders of Senior Indebtedness, the distribution may be made and the notice given to their Representative.

Upon any payment or distribution of assets of the Company referred to in this Article 12, the Trustee and the Holders shall be entitled to rely upon any order or decree made by any court of competent jurisdiction or upon any certificate of such Representative or of the liquidating trustee or agent or other Person making any distribution to the Trustee or to the Holders for the purpose of ascertaining the Persons entitled to participate in such distribution, the holders of Senior Indebtedness and other Indebtedness of the Company, the amount thereof or payable thereon, the amount or amounts paid or distributed thereon and all other facts pertinent thereto or to this Article 12.

Section 12.11 . Rights of Trustee and Paying Agent. Notwithstanding the provisions of this Article 12 or any other provision of this Indenture, the Trustee shall not be charged with knowledge of the existence of any facts that would prohibit the making of any payment or distribution by the Trustee, and the Trustee and any paying agent may continue to make payments on the Debt Securities, unless the Trustee shall have received at its Corporate Trust Office at least one Business Day prior to the date of such payment written notice that such payment is not to be made pursuant to this Article 12 and of the underlying facts that would cause the payment of any obligations with respect to the Debt Securities to violate this Article. Only the Company or a Representative may give the notice. Nothing in this Article 12 shall impair the claims of, or payments to, the Trustee under or pursuant to Section 7.06 of this Indenture.

The Trustee shall be entitled to rely on the delivery to it of a written notice by a Person representing himself to be a holder of Senior Indebtedness (or a Representative of such holder) to establish that such notice has been given by a holder of Senior Indebtedness (or a Representative of any such holder). In the event that the Trustee determines in good faith that further evidence is required with respect to the right of any Person as a holder of Senior Indebtedness to participate in any payment or distribution pursuant to this Article 12, the Trustee may request such Person to furnish evidence to the reasonable satisfaction of the Trustee as to the amount of Senior Indebtedness held by such Person, the extent to which such Person is entitled to participate in such payment or distribution and any other facts pertinent to the rights of such Person under this Article 12, and if such evidence is not furnished, the Trustee may defer any payment which it may be required to make for the benefit of such Person pursuant to the terms of this Indenture pending judicial determination as to the rights of such Person to receive such payment.

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The Trustee in its individual or any other capacity may hold Senior Indebtedness with the same rights it would have if it were not Trustee. Any agent may do the same with like rights.

Section 12.12 . Authorization to Effect Subordination. Each Holder of Debt Securities by the Holder’s acceptance thereof authorizes and directs the Trustee on the Holder’s behalf to take such action as may be necessary or appropriate to effectuate the subordination as provided in this Article 12, and appoints the Trustee to act as the Holder’s attorney-in-fact for any and all such purposes.

Section 12.13 . Subordination of Subsidiary Guarantees. The obligations of any subsidiary guarantor under any subsidiary guarantee of Debt Securities are subordinated in right of payment to the obligations of any guarantor under its Senior Debt in the same manner and to the same extent that the Debt Securities are subordinated to Senior Indebtedness of the Company pursuant to this Article 12.

Section 12.14 . Amendment to the Subordination Provisions of the Indenture. (a) No amendment may be made to the subordination provisions of the Indenture that adversely affects the rights of any holder of Senior Indebtedness then outstanding unless the holders of such Senior Indebtedness (or any group or representative thereof authorized to give a consent) consent to such change.

(b) Any amendment to Article 12 of this Indenture that adversely affects the rights of any Holder of Debt Securities will require the consent of the Holders of at least 66  ² / 3 % in aggregate principal amount of the Debt Securities then outstanding.

Section 12.15. Nothing in this Article 12 shall apply to claims of, or payments to, the Trustee hereunder, including pursuant to Section 7.06.

ARTICLE 13

M ISCELLANEOUS P ROVISIONS

Section 13.01 . Successors and Assigns of Company Bound by Indenture. All the covenant’s stipulations, promises and agreements in this Indenture contained by or in behalf of the Company or the Trustee shall bind its successors and assigns, whether so expressed or not.

Section 13.02 . Acts of Board, Committee or Officer of Successor Company Valid. Any act or proceeding by any provision of this Indenture authorized or required to be done or performed by any board, committee or officer of the Company shall and may be done and performed with like force and effect by the like board, committee or officer of any Successor Company.

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Section 13.03 . Required Notices or Demands. Except as otherwise expressly provided in this Indenture, any notice or demand which by any provision of this Indenture is required or permitted to be given or served by the Trustee or by the Holders to or on the Company may be given or served by being deposited first class mail, postage prepaid, in a post office letter box in the United States addressed (until another address is filed by the Company with the Trustee) as follows: Unit Corporation, 7130 South Lewis, Tulsa, Oklahoma 74136, Attention: Chief Financial Officer. Except as otherwise expressly provided in this Indenture, any notice, direction, request or demand by the Company or by any Holder to or upon the Trustee may be given or made, for all purposes, by being deposited first class mail, postage prepaid, in a post office letter box in the United States addressed to the corporate trust office of the Trustee initially at 246 Goose Lane, Suite 105, Guilford, CT 06437.

The Company or the Trustee by notice to the other may designate additional or different addresses for subsequent notices or communications.

Any notice required or permitted to a Registered Holder by the Company or the Trustee pursuant to the provisions of this Indenture shall be deemed to be properly mailed by being deposited first class mail, postage prepaid, in a post office letter box in the United States addressed to such Holder at the address of such Holder as shown on the Debt Security Register (and in the case of Global Securities, sent in accordance with the procedures of the Depositary). Any report pursuant to Section 313 of the Trust Indenture Act shall be transmitted in compliance with subsection (c) therein.

In the event of suspension of regular mail service or by reason of any other cause it shall be impracticable to give notice by mail, then such notification as shall be given with the approval of the Trustee shall constitute sufficient notice for every purpose thereunder.

Failure to mail a notice or communication to a Holder or any defect in it or any defect in any notice by publication as to a Holder shall not affect the sufficiency of such notice with respect to other Holders. If a notice or communication is mailed or published in the manner provided above, it is conclusively presumed duly given.

Section 13.04 . Indenture and Debt Securities to Be Construed in Accordance with the Laws of the State of New York. This Indenture and each Debt Security shall be deemed to be New York contracts, and for all purposes shall be construed in accordance with the laws of said State (without reference to principles of conflicts of law).

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Section 13.05 . Officers’ Certificate and Opinion of Counsel to Be Furnished upon Application or Demand by the Company. Upon any application or demand by the Company to the Trustee to take any action under any of the provisions of this Indenture, the Company shall furnish to the Trustee an Officers’ Certificate stating that all conditions precedent provided for in this Indenture relating to the proposed action have been complied with and an Opinion of Counsel stating that, in the opinion of such counsel, all such conditions precedent have been complied with, except that in the case of any such application or demand as to which the furnishing of such document is specifically required by any provision of this Indenture relating to such particular application or demand, no additional certificate or opinion need be furnished.

Each certificate (other than an Officers’ Certificate provided pursuant to Section 4.05) or opinion provided for in this Indenture and delivered to the Trustee with respect to compliance with a condition or covenant provided for in this Indenture shall include (1) a statement that the Person making such certificate or opinion has read such covenant or condition, (2) a brief statement as to the nature and scope of the examination or investigation upon which the statements or opinions contained in such certificate or opinion are based, (3) a statement that, in the opinion of such Person, he has made such examination or investigation as is necessary to enable him to express an informed opinion as to whether or not such covenant or condition has been complied with and (4) a statement as to whether or not, in the opinion of such Person, such condition or covenant has been complied with.

Section 13.06 . Payments Due on Legal Holidays. In any case where the date of maturity of interest on or principal of and premium, if any, on the Debt Securities of a series or the date fixed for redemption or repayment of any Debt Security or the making of any sinking fund payment shall not be a business day at any Place of Payment for the Debt Securities of such series, then payment of interest or principal and premium, if any, or the making of such sinking fund payment need not be made on such date at such Place of Payment, but may be made on the next succeeding business day at such Place of Payment with the same force and effect as if made on the date of maturity or the date fixed for redemption, and no interest shall accrue for the period after such date. If a record date is not a business day, the record date shall not be affected.

Section 13.07 . Provisions Required by Trust Indenture Act to Control. If and to the extent that any provision of this Indenture limits, qualifies or conflicts with another provision included in this Indenture which is required or deemed to be included herein by operation of the Trust Indenture Act, such required or deemed provision shall control. If any provision of this Indenture modifies or excludes any provision of the Trust Indenture Act which may be so modified or excluded, the latter provision shall be deemed to apply to this Indenture as so modified or excluded, as the case may be.

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Section 13.08 . Computation of Interest on Debt Securities. Interest, if any, on the Debt Securities shall be computed on the basis of a 360-day year of twelve 30-day months, except as may otherwise be provided pursuant to Section 2.03.

Section 13.09 . Rules by Trustee, Paying Agent and Registrar. The Trustee may make reasonable rules for action by or a meeting of Holders. The Registrar and any paying agent may make reasonable rules for their functions.

Section 13.10 . No Recourse Against Others. An incorporator or any past, present or future director, officer, employee or stockholder, as such, of the Company shall not have any liability for any obligations of the Company under the Debt Securities or this Indenture or for any claim based on, in respect of or by reason of such obligations or their creation. By accepting a Debt Security, each Holder shall waive and release all such liability. The waiver and release shall be part of the consideration for the issue of the Debt Securities.

Section 13.11 . Severability. In case any provision in this Indenture or the Debt Securities shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.

Section 13.12 . Effect of Headings. The article and section headings herein and in the Table of Contents are for convenience only and shall not affect the construction hereof.

Section 13.13 . Indenture May Be Executed in Counterparts. This Indenture may be executed in any number of counterparts, each of which shall be an original; but such counterparts shall together constitute but one and the same instrument.

[Signature Page Follows]

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The Trustee hereby accepts the trusts in this Indenture upon the terms and conditions herein set forth.

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

[Signature Page to Indenture]

Exhibit 4.2

UNIT CORPORATION,

THE SUBSIDIARY GUARANTORS PARTIES HERETO

AND

WILMINGTON TRUST FSB

as TRUSTEE

FIRST SUPPLEMENTAL INDENTURE

Dated as of May 18, 2011

$250,000,000

6  ⁵ / 8  % Senior Subordinated Notes due 2021

TABLE OF CONTENTS

i

ii

THIS FIRST SUPPLEMENTAL INDENTURE is made as of the 18th day of May, 2011, by and among UNIT CORPORATION, a Delaware corporation (the “ Company ”), the Subsidiary Guarantors (as herein defined) parties hereto (each, a “ Subsidiary Guarantor ” and, collectively, the “ Subsidiary Guarantors ”) and WILMINGTON TRUST FSB, a federal savings bank duly organized and existing under the laws of the United States of America, as trustee (the “ Trustee ”):

WHEREAS, the Company and the Trustee executed and delivered an Indenture, dated as of May 18, 2011 (the “ Original Indenture ”), to provide for the issuance by the Company from time to time of unsecured debentures, notes, and other evidences of indebtedness (the “ Debt Securities ”), to be issued in one or more series as provided in the Original Indenture;

WHEREAS, the Original Indenture is incorporated herein by this reference and the Original Indenture, as supplemented by this First Supplemental Indenture, is herein called the “ Indenture ”;

WHEREAS, under the Original Indenture, a new series of Debt Securities may at any time be established by the Board of Directors of the Company in accordance with the provisions of the Original Indenture and the terms of such series may be described by a supplemental indenture executed by the Company and the Trustee;

WHEREAS, the Company proposes to create under the Indenture a new series of Debt Securities;

WHEREAS, additional Debt Securities of other series hereafter established, except as may be limited in the Original Indenture as at the time supplemented and modified, may be issued from time to time pursuant to the Indenture as at the time supplemented and modified, and all Debt Securities issued by the Company of any one series need not be issued at the same time and, unless otherwise so provided, may be reopened for issuances of additional Debt Securities of such series; and

WHEREAS, all conditions necessary to authorize the execution and delivery of this First Supplemental Indenture and make it a valid and binding obligation of the Company and the Subsidiary Guarantors, in accordance with its terms, have been done or performed.

NOW THEREFORE, in consideration of the agreements and obligations set forth herein and for other good and valuable consideration, the sufficiency of which is hereby acknowledged, the parties hereto hereby agree as follows:

ARTICLE 1

6  ⁵ / 8 % S ENIOR S UBORDINATED N OTES D UE 2021

Section 1.01 . Establishment. There is hereby established a new series of Debt Securities to be issued under the Indenture, to be designated as the Company’s 6  ⁵ / 8 % Senior Subordinated Notes due 2021 (the “ Notes ”).

There are to be authenticated and delivered Notes, initially limited in aggregate principal amount of $250,000,000 and no further Notes shall be authenticated and delivered except as provided by the terms of the Original Indenture and the terms of this First Supplemental Indenture; provided , however , that the aggregate principal amount of the Notes may be increased in the future, without the consent of the holders of the Notes, on the same terms and with the same CUSIP and ISIN numbers as the Notes. The Notes shall be issued in fully registered form without coupons.

The Notes shall be issued in the form of one or more Global Securities (as defined below) in substantially the form set out in Exhibit A hereto. The initial Depositary with respect to the Notes shall be The Depository Trust Company.

Each Note shall be dated the date of authentication thereof and shall bear interest from the date of original issuance thereof or from the most recent Interest Payment Date to which interest has been paid or duly provided for.

Section 1.02 . Definitions. To the extent any term is defined in both the First Supplemental Indenture and the Original Indenture, the definition provided in the Original Indenture shall be deemed to be deleted in its entirety and replaced by the meaning specified in the First Supplemental Indenture. The following defined terms used herein with respect to the Notes shall, unless the context otherwise requires, have the meanings specified below. Capitalized terms used herein for which no definition is provided herein shall have the meanings set forth in the Original Indenture.

“ Acquired Indebtedness ” means Indebtedness (i) of a Person or any of its Subsidiaries existing at the time such Person becomes or is merged with and into a Restricted Subsidiary or (ii) assumed in connection with the acquisition of assets from such Person, in each case whether or not Incurred by such Person in connection with, or in anticipation or contemplation of, such Person becoming a Restricted Subsidiary or such acquisition. Acquired Indebtedness shall be deemed to have been Incurred, with respect to clause (i) of the preceding sentence, on the date such Person becomes or is merged with and into a Restricted Subsidiary and, with respect to clause (ii) of the preceding sentence, on the date of consummation of such acquisition of assets.

2

“ Additional Assets ” means:

(1) any property or assets (other than Indebtedness and Capital Stock) to be used by the Company or a Restricted Subsidiary in the Oil and Gas Business;

(2) capital expenditures by the Company or a Restricted Subsidiary in the Oil and Gas Business;

(3) the Capital Stock of a Person that becomes a Restricted Subsidiary as a result of the acquisition of such Capital Stock by the Company or a Restricted Subsidiary; or

(4) Capital Stock constituting a minority interest in any Person that at such time is a Restricted Subsidiary;

provided , however , that, in the case of clauses (3) and (4), such Restricted Subsidiary is primarily engaged in the Oil and Gas Business.

“ Adjusted Consolidated Net Tangible Assets ” means (without duplication), as of the date of determination, the remainder of:

3

4

“ Affiliate ” of any specified Person means any other Person, that directly or indirectly, is in Control of, is Controlled by, or is under common Control with, such Person.

“ Applicable Premium ” means, with respect to a Note at any Redemption Date, the greater of (i) 1.0% of the principal amount of such Note and (ii) the excess of (A) the present value at such time of (1) the redemption price of such Note at May 15, 2016 (expressed as a percentage of principal amount) plus (2) all required interest payments due on such Note through May 15, 2016, computed using a discount rate equal to the Treasury Rate plus 50 basis points, over (B) the then outstanding principal amount of such Note.

“ Asset Disposition ” means any direct or indirect sale, lease (other than an operating lease entered into in the ordinary course of the Oil and Gas Business), transfer, issuance or other disposition, or a series of related sales, leases, transfers, issuances or dispositions that are part of a common plan, of shares of Capital

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Stock of a Subsidiary (other than directors’ qualifying shares), property or other assets (each referred to for the purposes of this definition as a “ disposition ”) by the Company or any of its Restricted Subsidiaries, in each case outside the ordinary course of business including any disposition by means of a merger, consolidation or similar transaction.

Notwithstanding the preceding, the following items shall not be deemed to be Asset Dispositions:

(1) a disposition by a Restricted Subsidiary to the Company or by the Company or a Restricted Subsidiary to a Restricted Subsidiary;

(2) the disposition of cash or Cash Equivalents in the ordinary course of business;

(3) a disposition of Hydrocarbons or mineral products in the ordinary course of the Oil and Gas Business;

(4) a disposition of obsolete or worn out equipment or equipment that is no longer useful in the conduct of the business of the Company and its Restricted Subsidiaries and that is disposed of in each case in the ordinary course of business;

(5) transactions permitted by Section 3.10 of this First Supplement Indenture;

(6) an issuance of Capital Stock by a Restricted Subsidiary to the Company or to a Wholly-Owned Subsidiary;

(7) for purposes of Section 3.07 of this First Supplemental Indenture only, the making of a Permitted Investment or a disposition subject to Section 3.04 of this First Supplemental Indenture;

(8) dispositions of assets with an aggregate fair market value since the Issue Date of less than $10 million;

(9) dispositions in connection with the creation, encumbrance or existence of Permitted Liens or the exercise of any rights or remedies with respect thereof;

(10) dispositions of receivables in connection with the compromise, settlement or collection thereof in the ordinary course of business or in bankruptcy or similar proceedings and exclusive of factoring or similar arrangements;

(11) the licensing or sublicensing of intellectual property or other general intangibles and licenses, leases or subleases of other property in the ordinary course of business and which do not materially interfere with the business of the Company and its Restricted Subsidiaries;

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(12) any Production Payments and Reserve Sales, provided that any such Production Payments and Reserve Sales, other than incentive compensation programs on terms that are reasonably customary in the Oil and Gas Business for geologists, geophysicists and other providers of technical services to the Company or a Restricted Subsidiary, shall have been created, Incurred, issued, assumed or Guaranteed in connection with the acquisition or financing of, and no later than 60 days after the acquisition of, the property that is subject thereto;

(13) the sale or transfer (whether or not in the ordinary course of the Oil and Gas Business) of oil and/or gas properties or direct or indirect interests in real property; provided, that at the time of such sale or transfer such properties do not have associated with them any proved reserves capable of being produced in material economic quantities;

(14) the abandonment, farm-out, exchange, lease or sublease of developed or undeveloped oil and/or gas properties or interests therein in the ordinary course of business or in exchange for oil and/or gas properties or interests therein owned or held by another Person;

(15) an Asset Swap effected in compliance with the covenant described under Section 3.07 hereof;

(16) a disposition of oil and natural gas properties in connection with tax credit transactions complying with Section 29 or any successor or analogous provisions of the Code;

(17) surrender or waiver of contract rights, oil and gas leases, or the settlement, release or surrender of contract, tort or other claims of any kind; and

(18) Permitted Liens.

“ Asset Swap ” means a substantially concurrent purchase and sale or exchange of oil and gas properties or interests therein or other assets or properties used or useful in the Oil and Gas Business, including Capital Stock of any Person who holds any such properties, interests or assets, between the Company or any of its Restricted Subsidiaries and another Person; provided that any cash received must be applied in accordance with Section 3.07 of this First Supplemental Indenture

“ Attributable Indebtedness ” in respect of a Sale/Leaseback Transaction means, as at the time of determination, the present value (discounted at the interest rate borne by the Notes, compounded semi-annually) of the total obligations of the lessee for rental payments during the remaining term of the lease included in such Sale/Leaseback Transaction (including any period for which such lease has been extended).

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“ Average Life ” means, as of the date of determination, with respect to any Indebtedness or Preferred Stock, the quotient obtained by dividing (1) the sum of the products of the numbers of years from the date of determination to the dates of each successive scheduled principal payment of such Indebtedness or redemption or similar payment with respect to such Preferred Stock multiplied by the amount of such payment by (2) the sum of all such payments.

“ Bank Indebtedness ” means any and all amounts, whether outstanding on the Issue Date or Incurred after the Issue Date, payable by the Company under or in respect of a Credit Facility, including the Senior Credit Agreement, and any related notes, collateral documents, letters of credit and guarantees and any Interest Rate Agreement entered into in connection with the Credit Facility, including principal, premium, if any, interest (including interest accruing on or after the filing of any petition in bankruptcy or for reorganization relating to the Company at the rate specified therein, whether or not a claim for post-filing interest is allowed in such proceedings), fees, charges, expenses, reimbursement obligations, guarantees and all other amounts payable thereunder or in respect thereof.

“ Board of Directors ” means, as to any Person, the board of directors of such Person or a duly authorized committee of such board of directors.

“ Capital Lease ” means, with respect to any Person, any lease of property (whether real, personal, or mixed) by such Person or its Subsidiaries as lessee that would be capitalized on a balance sheet of such Person or its Subsidiaries prepared in conformity with GAAP, other than, in the case of such Person or its Subsidiaries, any such lease under which such Person or any of its Subsidiaries is the lessor.

“ Capital Lease Obligations ” means, with respect to any Person, the capitalized amount of all obligations of such Person and its Subsidiaries under Capital Leases, as determined on a consolidated basis in conformity with GAAP.

“ Capital Stock ” of any Person means any and all shares, interests, rights to purchase, warrants, options, participation or other equivalents of or interests in (however designated) equity of such Person, including any Preferred Stock, but excluding any debt securities convertible into such equity.

“ Cash Equivalents ” means:

(1) securities issued or directly and fully guaranteed or insured by the United States Government or any agency or instrumentality of the United States (provided that the full faith and credit of the United States is pledged in support thereof), having a maturity within one year after the date of acquisition thereof;

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(2) marketable general obligations issued by any state of the United States of America or any political subdivision of any such state or any public instrumentality thereof maturing within one year after the date of acquisition thereof and, at the time of such acquisition, having a credit rating of at least “A” or the equivalent thereof from either Standard & Poor’s Ratings Services or Moody’s Investors Service, Inc. (or an equivalent rating by another nationally recognized rating agency if both of the two named rating agencies cease publishing ratings of investments);

(3) certificates of deposit, time deposits, eurodollar time deposits, overnight bank deposits or bankers’ acceptances having maturities of not more than one year after the date of acquisition thereof issued by any commercial bank the long-term debt of which is rated at the time of acquisition at least “A” or the equivalent thereof by Standard & Poor’s Ratings Services, or “A” or the equivalent thereof by Moody’s Investors Service, Inc. (or an equivalent rating by another nationally recognized rating agency if both of the two named rating agencies cease publishing ratings of investments), and having combined capital and surplus in excess of $500 million;

(4) repurchase obligations with a term of not more than seven days for underlying securities of the types described in clauses (1), (2) and (3) above entered into with any bank meeting the qualifications specified in clause (3) above;

(5) commercial paper rated at the time of acquisition thereof at least “ A-2 ” or the equivalent thereof by Standard & Poor’s Ratings Services or “P-2” or the equivalent thereof by Moody’s Investors Service, Inc. (or an equivalent rating by another nationally recognized rating agency if both of the two named rating agencies cease publishing ratings of investments), and in any case maturing within one year after the date of acquisition thereof; and

(6) interests in any investment company or money market fund which invests 95% or more of its assets in instruments of the type specified in clauses (1) through (5) above.

“ Change of Control ” means:

(1) Any “person” or “group” of related persons (as such terms are used in Sections 13(d) and 14(d) of the Exchange Act) is or becomes the beneficial owner (as defined in Rules 13d-3 and 13d-5 under the Exchange Act, except that such person or group shall be deemed to have “beneficial ownership” of all shares that such person or group has the right to acquire, whether such right is exercisable immediately or only after the passage of time), directly or indirectly, of more than 50% of the total voting power of the Voting Stock of the Company (or its successor by merger, consolidation or purchase of all or substantially all of its assets) (for the purposes of this clause, such person or group shall be deemed to beneficially own any Voting Stock of the Company held by a parent entity of the Company, if such person or group “beneficially owns” (as defined above), directly or indirectly, more than 50% of the voting power of the Voting Stock of such parent entity); or

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(2) the first day on which a majority of the members of the Board of Directors of the Company are not Continuing Directors; or

(3) the sale, lease, transfer, conveyance or other disposition (other than by way of merger or consolidation), in one or a series of related transactions, of all or substantially all of the assets of the Company and its Restricted Subsidiaries taken as a whole to any “person” (as such term is used in Sections 13(d) and 14(d) of the Exchange Act); or

(4) the adoption by the stockholders of the Company of a plan or proposal for the liquidation or dissolution of the Company.

“ Commodity Agreements ” means, in respect of any Person, any futures contract, forward contract, commodity swap agreement, commodity option agreement or other similar agreement or arrangement in respect of Hydrocarbons purchased, used, produced, processed or sold by such Person and designed to protect such Person against fluctuations in Hydrocarbon prices.

“ Common Stock ” means with respect to any Person, any and all shares, interests or other participations in, and other equivalents (however designated and whether voting or nonvoting) of such Person’s common stock whether or not outstanding on the Issue Date, and includes, without limitation, all series and classes of such common stock.

“ Consolidated Coverage Ratio ” means as of any date of determination, the ratio of (x) the aggregate amount of Consolidated EBITDA for the period of the most recent four consecutive fiscal quarters ending prior to the date of such determination for which consolidated financial statements of the Company are in existence to (y) Consolidated Interest Expense for such four fiscal quarters; provided , however , that:

(1) if the Company or any Restricted Subsidiary:

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(2) if since the beginning of such period the Company or any Restricted Subsidiary shall have made any Asset Disposition or the transaction giving rise to the need to calculate the Consolidated Coverage Ratio is such an Asset Disposition:

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(3) if since the beginning of such period the Company or any Restricted Subsidiary (by merger or otherwise) shall have made an Investment in any Restricted Subsidiary (or any Person which becomes a Restricted Subsidiary or is merged with or into the Company or a Restricted Subsidiary) or an acquisition of assets, including any acquisition of assets occurring in connection with a transaction giving rise to the need to calculate the Consolidated Coverage Ratio, which constitutes all or substantially all of a company, division, operating unit, segment, business, group of related assets or line of business, Consolidated EBITDA and Consolidated Interest Expense for such period will be calculated after giving pro forma effect thereto (including the Incurrence of any Indebtedness) as if such Investment or acquisition occurred on the first day of such period; and

(4) if since the beginning of such period any Person that subsequently became a Restricted Subsidiary or was merged with or into the Company or any Restricted Subsidiary since the beginning of such period shall have Incurred any Indebtedness or discharged any Indebtedness, made any Asset Disposition or any Investment or acquisition of assets that would have required an adjustment pursuant to clause (2) or (3) above if made by the Company or a Restricted Subsidiary during such period, Consolidated EBITDA and Consolidated Interest Expense for such period will be calculated after giving pro forma effect thereto as if such Asset Disposition or Investment or acquisition of assets occurred on the first day of such period.

For purposes of this definition, whenever pro forma effect is to be given to any calculation under this definition, the pro forma calculations will be determined in good faith by a responsible financial or accounting officer of the Company (including pro forma expense and cost reductions calculated on a basis consistent with Regulation S-X under the Securities Act). If any Indebtedness bears a floating rate of interest and is being given pro forma effect, the interest expense on such Indebtedness will be calculated as if the rate in effect on the date of determination had been the applicable rate for the entire period (taking into account any Interest Rate Agreement applicable to such Indebtedness but if the remaining term of such Interest Rate Agreement is less than 12 months, then such Interest Rate Agreement shall only be taken into account for that portion of the period equal to the remaining term thereof). If any Indebtedness that is being given pro forma effect bears an interest rate at the option of the Company, the interest rate shall be calculated by applying such optional rate chosen by the Company.

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“ Consolidated EBITDA ” for any period means, without duplication, the Consolidated Net Income for such period, plus the following to the extent deducted in calculating such Consolidated Net Income:

(1) Consolidated Interest Expense;

(2) Consolidated Income Taxes;

(3) consolidated depletion, depreciation and amortization expenses;

(4) consolidated impairment charges recorded in connection with the application of GAAP codification of Accounting Standards (ASC) 350 “Goodwill and Other Intangibles” and ASC 360 “Accounting for the Impairment or Disposal of Long Lived Assets;”

(5) consolidated exploration expenses, if applicable;

(6)(a) any write-off of deferred financing costs, (b) any capitalized interest, and (c) the interest portion of any deferred payment obligations; and

(7) other consolidated non-cash charges reducing Consolidated Net Income (excluding any such non-cash charge to the extent it represents an accrual of or reserve for cash charges in any future period or amortization of a prepaid cash expense that was paid in a prior period not included in the calculation);

less, to the extent included in calculating such Consolidated Net Income and in excess of any costs or expenses attributable thereto that were deducted in calculating such Consolidated Net Income, the sum of (x) the amount of deferred revenues that are amortized during such period and are attributable to reserves that are subject to Volumetric Production Payments, and (y) amounts recorded in accordance with GAAP as repayments of principal and interest pursuant to Dollar-Denominated Production Payments.

Notwithstanding the preceding sentence, the items described in clauses (2) through (6) above relating to amounts of a Restricted Subsidiary of a Person will be added to Consolidated Net Income to compute Consolidated EBITDA of such Person only to the extent (and in the same proportion) that the net income (loss) of such Restricted Subsidiary was included in calculating the Consolidated Net Income of such Person and, to the extent the amounts set forth in clauses (2) through (6) above are in excess of those necessary to offset a net loss of such Restricted Subsidiary or if such Restricted Subsidiary has net income for such period included in Consolidated Net Income, only if a corresponding amount would not be prohibited at the date of determination to be dividended to the Company by such Restricted Subsidiary pursuant to the terms of its charter and all agreements, instruments, judgments, decrees, orders, statutes, rules and governmental regulations applicable to that Restricted Subsidiary or its stockholders, except for restrictions under any Credit Facility.

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“ Consolidated Income Taxes ” means, with respect to any Person for any period, taxes imposed upon such Person or other payments required to be made by such Person by any governmental authority which taxes or other payments are (x) calculated by reference to the income or profits of such Person or such Person and its Subsidiaries, or (y) any franchise taxes or equity taxes (in each case to the extent included in computing Consolidated Net Income for such period), regardless of whether such taxes or payments are required to be remitted to any governmental authority.

“ Consolidated Interest Expense ” means, for any period, the consolidated interest expense of the Company and its consolidated Restricted Subsidiaries, whether paid or accrued, plus, to the extent not included in such interest expense:

(1) interest expense attributable to Capital Lease Obligations and the interest portion of rent expense associated with Attributable Indebtedness in respect of the relevant lease giving rise thereto, determined as if such lease were a Capital Lease in accordance with GAAP and the interest component of any deferred payment obligations;

(2) amortization of debt discount and debt issuance cost (provided that any amortization of bond premium will be credited to reduce Consolidated Interest Expense unless, pursuant to GAAP, such amortization of bond premium has otherwise reduced Consolidated Interest Expense);

(3) non-cash interest expense;

(4) commissions, discounts and other fees and charges owed with respect to letters of credit and bankers’ acceptance financing;

(5) the interest expense on Indebtedness of another Person that is Guaranteed by such Person or one of its Restricted Subsidiaries or secured by a Lien on assets of such Person or one of its Restricted Subsidiaries;

(6) costs associated with Hedging Obligations (including amortization of fees) provided , however , that if Hedging Obligations result in net benefits rather than costs, such net benefits shall be credited to reduce Consolidated Interest Expense unless, pursuant to GAAP, such net benefits are otherwise reflected in Consolidated Net Income;

(7) the consolidated interest expense of such Person and its Restricted Subsidiaries that was capitalized during such period;

(8) the product of (a) all dividends paid or payable, in cash, Cash Equivalents or Indebtedness or accrued during such period on any series of Disqualified Stock of such Person or on Preferred Stock of its Restricted Subsidiaries payable to a party other than the Company or a Wholly-Owned Subsidiary, times (b) a fraction, the numerator of which is one and the denominator of which is one minus the then current combined federal, state, provincial and local statutory tax rate of such Person, expressed as a decimal, in each case, on a consolidated basis and in accordance with GAAP;

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(9) Receivables Fees; and

(10) the cash contributions to any employee stock ownership plan or similar trust to the extent such contributions are used by such plan or trust to pay interest or fees to any Person (other than the Company) in connection with Indebtedness Incurred by such plan or trust.

For the purpose of calculating the Consolidated Coverage Ratio in connection with the Incurrence of any Indebtedness described in the final paragraph of the definition of “ Indebtedness ,” the calculation of Consolidated Interest Expense shall include all interest expense (including any amounts described in clauses (1) through (10) above) relating to any Indebtedness of the Company or any Restricted Subsidiary described in the final paragraph of the definition of “ Indebtedness .”

For purposes of the foregoing, total interest expense will be determined (i) after giving effect to any net payments made or received by the Company and its Subsidiaries with respect to Interest Rate Agreements and (ii) exclusive of amounts classified as other comprehensive income in the balance sheet of the Company. Notwithstanding anything to the contrary contained herein, commissions, discounts, yield and other fees and charges Incurred in connection with any transaction pursuant to which the Company or its Restricted Subsidiaries may sell, convey or otherwise transfer or grant a security interest in any accounts receivable or related assets shall be included in Consolidated Interest Expense.

“ Consolidated Leverage Ratio ” means, as of any date of determination, the ratio of total Indebtedness of the Company and its consolidated Restricted Subsidiaries as of that date to the Company’s Consolidated EBITDA for the four full fiscal quarters immediately preceding the determination date, with such adjustments to the amount of Indebtedness and Consolidated EBITDA as are consistent with the adjustment provisions set forth in the definition of “Consolidated Coverage Ratio.”

“ Consolidated Net Income ” means, for any period, the net consolidated income (loss) of the Company and its consolidated Subsidiaries determined in accordance with GAAP; provided , however , that there will not be included in such Consolidated Net Income:

(1) any net income (loss) of any Person (other than the Company) if such Person is not a Restricted Subsidiary, except that:

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(2) any net income (but not loss) of any Restricted Subsidiary if such Subsidiary is subject to restrictions, directly or indirectly, on the payment of dividends or the making of distributions by such Restricted Subsidiary, directly or indirectly, to the Company, except that:

(3) any after tax gain (loss) realized upon the sale or other disposition of any property, plant or equipment of the Company or its consolidated Restricted Subsidiaries (including pursuant to any Sale/Leaseback Transaction) which is not sold or otherwise disposed of in the ordinary course of business and any gain (loss) realized upon the sale or other disposition of any Capital Stock of any Person;

(4) any after tax extraordinary gain or loss, along with any related provisions for taxes on such gain or loss and all related fees and expenses;;

(5) the cumulative effect of a change in accounting principles;

(6) any asset impairment writedowns on Oil and Gas Properties under GAAP or SEC guidelines;

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(7) any consolidated impairment charges recorded in connection with the application of ASC 350 “Goodwill and Other Intangibles;”

(8) any unrealized non-cash gains or losses on charges in respect of Hedging Obligations (including those resulting from the application of ASC 815);

(9) income or loss attributable to discontinued operations (including, without limitation. operations disposed of during such period whether or not such operations were classified as discontinued);

(10) all deferred financing costs written off, and premiums paid, in connection with any early extinguishment of Indebtedness; and

(11) any non-cash compensation charge arising from any grant of stock, stock options or other equity based awards; provided that the proceeds resulting from any such grant will be excluded from clause 3(ii) of the first paragraph of the covenant described under Section 3.04 hereof.

“ Continuing Directors ” means the individuals who, as of the Issue Date, are directors of the Company and any individual becoming a director of the Company subsequent to the Issue Date whose election, nomination for election by the Company’s stockholders or appointment, was approved by a majority of the then Continuing Directors (either by a specific vote or by approval of the proxy statement of the Company in which such individual is named as a nominee for election as a director, without objection to such nomination).

“ Control ” of a Person means the power to direct the management and policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise; and the terms “ Controlling ” and “ Controlled ” have meanings correlative of the foregoing.

“ Credit Facility ” means, with respect to the Company or any Subsidiary Guarantor, one or more credit facilities (including, without limitation, the Senior Credit Agreement) or commercial paper facilities providing for revolving credit loans, term loans, receivables financing (including through the sale of receivables to such lenders or to special purpose entities formed to borrow from such lenders against such receivables) or letters of credit, in each case, as amended, restated, modified, renewed, refunded, replaced or refinanced in whole or in part from time to time (including successive amendments, restatements, modifications, renewals, refunds, replacements or refinancings and whether or not with the original administrative agent and lenders or another administrative agent or agents or other lenders and whether provided under the original Senior Credit Agreement or any other credit or other agreement or indenture).

“ Currency Agreement ” means in respect of a Person any foreign exchange contract, currency swap agreement, futures contract, option contract or other similar agreement as to which such Person is a party or a beneficiary.

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“ Default ” means any event which, with notice or passage of time or both, would constitute an Event of Default.

“ Designated Senior Indebtedness ” means (1) the Bank Indebtedness (to the extent such Bank Indebtedness constitutes Senior Indebtedness), including the Senior Credit Agreement, and (2) any other Senior Indebtedness which, at the date of determination, has an aggregate principal amount outstanding of, or under which, at the date of determination, the holders thereof are committed to lend up to, at least $25 million and is specifically designated in the instrument evidencing or governing such Senior Indebtedness as “ Designated Senior Indebtedness ” for purposes of the Indenture.

“ Disqualified Stock ” means, with respect to any Person, any Capital Stock of such Person which by its terms (or by the terms of any security into which it is convertible or for which it is exchangeable) or upon the happening of any event:

(1) matures or is mandatorily redeemable pursuant to a sinking fund obligation or otherwise;

(2) is convertible or exchangeable for Indebtedness or Disqualified Stock (excluding Capital Stock which is convertible or exchangeable solely at the option of the Company or a Restricted Subsidiary); or

(3) is redeemable at the option of the holder of the Capital Stock in whole or in part,

in each case on or prior to the date that is 91 days after the earlier of the date (a) of the Stated Maturity of the Notes or (b) the first date after the Issue Date on which there are no Notes outstanding, provided that only the portion of Capital Stock which so matures or is mandatorily redeemable, is so convertible or exchangeable or is so redeemable at the option of the holder thereof prior to such date will be deemed to be Disqualified Stock; provided, further that any Capital Stock that would constitute Disqualified Stock solely because the holders thereof have the right to require the Company to repurchase such Capital Stock upon the occurrence of a change of control or asset disposition (each defined in a substantially identical manner to the corresponding definitions in the Indenture) shall not constitute Disqualified Stock if the terms of such Capital Stock (and all such securities into which it is convertible or for which it is ratable or exchangeable) provide that the Company may not repurchase or redeem any such Capital Stock (and all such securities into which it is convertible or for which it is ratable or exchangeable) pursuant to such provision prior to compliance by the Company with Section 3.07 and Section 3.14 of this First Supplemental Indenture and such repurchase or redemption complies with Section 3.04 of this First Supplement Indenture.

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“ Dollar-Denominated Production Payments ” means production payment obligations recorded as liabilities in accordance with GAAP, together with all undertakings and obligations in connection therewith.

“ Domestic Subsidiary ” means any Restricted Subsidiary that is organized under the laws of the United States of America or any state thereof or the District of Columbia.

“ Events of Default ” has the meaning set forth in Article 4.

“ Foreign Subsidiary ” means any Restricted Subsidiary that is not organized under the laws of the United States of America or any state thereof or the District of Columbia and any Subsidiary of such Restricted Subsidiary.

“ GAAP ” means generally accepted accounting principles in the United States which are in effect from time to time. At any time after the Issue Date, the Company may elect to apply International Financial Reporting Standards (“IFRS”) accounting principles in lieu of GAAP and, upon any such election, references herein to GAAP shall thereafter be construed to mean IFRS from time to time; provided that any such election, once made, shall be irrevocable; provided, further, that any calculation or determination in the Indenture that requires the application of GAAP for periods that include fiscal quarters ended prior to the Company’s election to apply IFRS shall remain as previously calculated or determined in accordance with GAAP. The Company shall give notice of any such election made in accordance with this definition to the Trustee.

“ Guarantee ” means any obligation, contingent or otherwise, of any Person directly or indirectly guaranteeing any Indebtedness of any other Person and any obligation, direct or indirect, contingent or otherwise, of such Person:

(1) to purchase or pay (or advance or supply funds for the purchase or payment of) such Indebtedness of such other Person (whether arising by virtue of partnership arrangements, or by agreement to keep-well, to purchase assets, goods, securities or services, to take-or-pay, or to maintain financial statement conditions or otherwise); or

(2) entered into for purposes of assuring in any other manner the obligee of such Indebtedness of the payment thereof or to protect such obligee against loss in respect thereof (in whole or in part);

provided , however , that the term “ Guarantee ” will not include endorsements for collection or deposit in the ordinary course of business. The term “ Guarantee ” used as a verb has a corresponding meaning.

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“ Guarantor Senior Indebtedness ” means, with respect to a Subsidiary Guarantor, the following obligations, whether outstanding on the Issue Date or thereafter issued, without duplication:

(1) any Guarantee of the Bank Indebtedness by such Subsidiary Guarantor and all other Guarantees by such Subsidiary Guarantor of Senior Indebtedness of the Company or Guarantor Senior Indebtedness of any other Subsidiary Guarantor; and

(2) all obligations consisting of principal of and premium, if any, accrued and unpaid interest on, and fees and other amounts relating to, all other Indebtedness of the Subsidiary Guarantor. Guarantor Senior Indebtedness includes interest accruing on or after the filing of any petition in bankruptcy or for reorganization relating to the Subsidiary Guarantor regardless of whether post-filing interest is allowed in such proceeding.

Notwithstanding anything to the contrary in the preceding paragraph, Guarantor Senior Indebtedness will not include:

(1) any Indebtedness Incurred in violation of the Indenture;

(2) any obligations of such Subsidiary Guarantor to the Company or another Subsidiary;

(3) any liability for federal, state, local, foreign or other taxes owed or owing by such Subsidiary Guarantor;

(4) any accounts payable or other liability to trade creditors arising in the ordinary course of business (including Guarantees thereof or instruments evidencing such liabilities);

(5) any Indebtedness, Guarantee or obligation of such Subsidiary Guarantor that is expressly subordinate or junior in right of payment to any other Indebtedness, Guarantee or obligation of such Subsidiary Guarantor, including, without limitation, any Guarantor Senior Subordinated Indebtedness and Guarantor Subordinated Obligations of such Subsidiary Guarantor; or

(6) any Capital Stock.

“ Guarantor Senior Subordinated Indebtedness ” means, with respect to a Subsidiary Guarantor, the obligations of such Subsidiary Guarantor under the Subsidiary Guarantee and any other Indebtedness of such Subsidiary Guarantor (whether outstanding on the Issue Date or thereafter Incurred) that specifically provides that such Indebtedness is to rank equally in right of payment with the obligations of such Subsidiary Guarantor under the Subsidiary Guarantee and is not expressly subordinated by its terms in right of payment to any Indebtedness of such Subsidiary Guarantor which is not Guarantor Senior Indebtedness of such Subsidiary Guarantor.

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“ Guarantor Subordinated Obligation ” means, with respect to a Subsidiary Guarantor, any Indebtedness of such Subsidiary Guarantor (whether outstanding on the Issue Date or thereafter Incurred) which is expressly subordinate in right of payment to the obligations of such Subsidiary Guarantor under its Subsidiary Guarantee pursuant to a written agreement.

“ Hedging Obligations ” of any Person means the obligations of such Person pursuant to any Interest Rate Agreement or Currency Agreement or Commodity Agreement.

“ Holder ” means a Person in whose name a Note is registered in the Security Registrar’s books.

“ Hydrocarbons ” means oil, gas, casinghead gas, drip gasoline, natural gasoline, condensate, distillate, liquid hydrocarbons, gaseous hydrocarbons, and all products, by-products and all other substances refined, separated, settled or derived therefrom or the processing thereof, and all other minerals and substances, including, but not limited to, liquified petroleum gas, natural gas, kerosene, sulphur, lignite, coal, uranium, thorium, iron, geothermal steam, water, carbon dioxide, helium, and any and all other minerals, ores, or substances of value, and the products and proceeds therefrom, including, without limitation, all gas resulting from the in-situ combustion of coal or lignite.

“ Incur ” means issue, create, assume, Guarantee, incur or otherwise become liable for; provided , however , that any Indebtedness or Capital Stock of a Person existing at the time such Person becomes a Restricted Subsidiary (whether by merger, consolidation, acquisition or otherwise) will be deemed to be Incurred by such Restricted Subsidiary at the time it becomes a Restricted Subsidiary; and the terms “ Incurred ” and “ Incurrence ” have meanings correlative to the foregoing.

“ Indebtedness ” means, as applied to any Person, without duplication:

(1) all obligations of such Person for borrowed money;

(2) all obligations of such Person for the deferred purchase price of property or services (other than property and services purchased, and expense accruals and deferred compensation items arising, in the ordinary course of business);

(3) all obligations of such Person evidenced by notes, bonds, debentures, mandatorily redeemable preferred stock or other similar instruments (other than performance, surety and appeals bonds arising in the ordinary course of business);

(4) all payment obligations created or arising under any conditional sale, deferred price or other title retention agreement with respect to property acquired by such Person (unless the rights and remedies of the seller or lender under such agreement in the event of default are limited to repossession or sale of such property);

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(5) any Capital Lease Obligation of such Person, other than obligations under oil and gas leases entered into in the ordinary course of business;

(6) all reimbursement, payment or similar obligations, contingent or otherwise, of such Person under acceptance, letter of credit or similar facilities (other than letters of credit in support of trade obligations or incurred in connection with public liability insurance, workers’ compensation, unemployment insurance, old-age pensions and other social security benefits other than in respect of employee benefit plans subject to ERISA);

(7) all obligations of such Person, contingent or otherwise, under any guarantee by such Person of the obligations of another Person of the type referred to in clauses (1) through (6) above;

(8) the principal component or liquidation preference of all obligations of such Person with respect to the redemption, repayment or other repurchase of any Disqualified Stock or, with respect to any Subsidiary that is not a Subsidiary Guarantor, any Preferred Stock (but excluding, in each case, any accrued dividends);

(9) to the extent not otherwise included in this definition, net obligations of such Person under Commodity Agreements, Currency Agreements and Interest Rate Agreements (the amount of any such obligations to be equal at any time to the termination value of such agreement or arrangement giving rise to such obligation that would be payable by such Person at such time); and

(10) all obligations referred to in clauses (1) through (6) above secured by (or for which the holder of such Indebtedness has an existing right, contingent or otherwise, to be secured by) any mortgage or security interest in property (including without limitation accounts, contract rights and general intangibles) owned by such Person and as to which such Person has not assumed or become liable for the payment of such obligations other than to the extent of the property subject to such mortgage or security interest;

except that Indebtedness of the type referred to in clauses (7) and (10) above will be included within the definition of “ Indebtedness ” only to the extent of the least of (a) the amount of the underlying Indebtedness referred to in the applicable clause (1) through (6) above; (b) in the case of clause (7), the limit on recoveries, if any, from such Person under obligations of the type referred to in clause (7) above, and (c) in the case of clause (10), the aggregate value (as determined in good faith by the board of directors or similar governing body of such Person) of the property of such Person subject to such mortgage or security interest.

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In addition, “ Indebtedness ” of any Person shall include Indebtedness described in the preceding paragraph that would not appear as a liability on the balance sheet of such Person if:

(1) such Indebtedness is the obligation of a partnership or joint venture that is not a Restricted Subsidiary (a “ Joint Venture ”);

(2) such Person or a Restricted Subsidiary of such Person is a general partner of the Joint Venture (a “ General Partner ”); and

(3) there is recourse, by contract or operation of law, with respect to the payment of such Indebtedness to property or assets of such Person or a Restricted Subsidiary of such Person;

in which case, such Indebtedness shall be included in an amount not to exceed:

Notwithstanding the preceding, “Indebtedness” shall not include:

(1) Production Payments and Reserve Sales;

(2) any obligation of a Person in respect of a farm-in agreement or similar arrangement whereby such Person agrees to pay all or a share of the drilling, completion or other expenses of an exploratory or development well (which agreement may be subject to a maximum payment obligation, after which expenses are shared in accordance with the working or participation interest therein or in accordance with the agreement of the parties) or perform the drilling, completion or other operation on such well in exchange for an ownership interest in an oil or gas property;

(3) any obligations under Hedging Obligations; provided that such agreements are entered into for bona fide hedging purposes of the Company or its Restricted Subsidiaries (as determined in good faith by the Board of Directors or senior management of the Company, whether or not accounted for as a hedge in accordance with GAAP);

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(4) any obligation arising from agreements of the Company or a Restricted Subsidiary providing for indemnification, Guarantees, adjustment of purchase price, holdbacks, contingency payment obligations or similar obligations (other than Guarantees of Indebtedness), in each case, Incurred or assumed in connection with the acquisition or disposition of any business, assets or Capital Stock of a Restricted Subsidiary, provided that such Indebtedness is not reflected on the face of the balance sheet of the Company or any Restricted Subsidiary;

(5) any obligation arising from the honoring by a bank or other financial institution of a check, draft or similar instrument (except in the case of daylight overdrafts) drawn against insufficient funds in the ordinary course of business; provided, however, that such Indebtedness is extinguished within five business days of Incurrence;

(6) in-kind obligations relating to net oil or natural gas balancing positions arising in the ordinary course of business; and

(7) all contracts and other obligations, agreements, instruments or arrangements described in clauses (20), (21) or (22), of the definition of “Permitted Liens.”

“ Interest Payment Date ” means May 15 and November 15 of each year, commencing November 15, 2011.

“ Interest Rate Agreement ” means with respect to any Person any interest rate protection agreement, interest rate futures contracts, interest rate option agreement, interest rate swap agreement, interest rate cap agreement, interest rate collar agreement, interest rate hedge agreement or other similar agreement or arrangement as to which such Person is party or a beneficiary.

“ Investment ” means, with respect to any Person, all investments by such Person in other Persons (including Affiliates) in the form of any direct or indirect advance, loan (other than advances or extensions of credit to employees, directors or customers in the ordinary course of business) or other extensions of credit (including by way of Guarantee or similar arrangement, but excluding any debt or extension of credit represented by a bank deposit other than a time deposit) or capital contribution to (by means of any transfer of cash or other property or any payment for property or services), or any purchase or acquisition of Capital Stock, Indebtedness or other similar instruments issued by, such Person and all other items that are or would be classified as investments on a balance sheet prepared in accordance with GAAP; provided that none of the following will be deemed to be an Investment:

(1) Hedging Obligations Incurred in the ordinary course of business and in compliance with the Indenture;

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(2) endorsements of negotiable instruments and documents in the ordinary course of business; and

(3) an acquisition of assets, Capital Stock or other securities by the Company or a Subsidiary for consideration to the extent such consideration consists of Common Stock of the Company.

For purposes of Section 3.04 of this First Supplemental Indenture,

(1) “ Investment ” will include the portion (proportionate to the Company’s equity interest in a Restricted Subsidiary to be designated as an Unrestricted Subsidiary) of the fair market value of the net assets of such Restricted Subsidiary at the time that such Restricted Subsidiary is designated an Unrestricted Subsidiary; provided , however , that upon a redesignation of such Subsidiary as a Restricted Subsidiary, the Company will be deemed to continue to have a permanent “ Investment ” in an Unrestricted Subsidiary in an amount (if positive) equal to (a) the Company’s “ Investment ” in such Subsidiary at the time of such redesignation less (b) the portion (proportionate to the Company’s equity interest in such Subsidiary) of the fair market value of the net assets (as conclusively determined by the Board of Directors of the Company in good faith) of such Subsidiary at the time that such Subsidiary is so re-designated a Restricted Subsidiary; and

(2) any property transferred to or from an Unrestricted Subsidiary will be valued at its fair market value at the time of such transfer, in each case as determined in good faith by the Board of Directors of the Company.

“ Investment Grade Rating ” means a rating equal to or higher than Baa3 (or the equivalent) by Moody’s Investors Service, Inc. and BBB- (or the equivalent) by Standard & Poor’s Ratings Services (or an equivalent rating by another nationally recognized rating agency if both of the two named rating agencies cease publishing ratings of investments), in each case, with a stable or better outlook.

“ Issue Date ” means May 18, 2011.

“ Lien ” means any mortgage, pledge, security interest, encumbrance, lien or similar charge of any kind (including any conditional sale or other title retention agreement or lease in the nature thereof); provided, that in no event shall an operating lease be deemed to constitute a Lien.

“ Minority Interest ” means the percentage interest represented by any shares of stock of any class of Capital Stock of a Restricted Subsidiary that are not owned by the Company or a Restricted Subsidiary.

“ Moody’s ” means Moody’s Investors Service, Inc., a subsidiary of Moody’s Corporation, and its successors.

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“ Net Available Cash ” from an Asset Disposition means cash payments received (including any cash payments received by way of deferred payment of principal pursuant to a note or installment receivable or otherwise and net proceeds from the sale or other disposition of any securities received as consideration, but only as and when received, but excluding any other consideration received in the form of assumption by the acquiring Person of Indebtedness or other obligations relating to the properties or assets that are the subject of such Asset Disposition or received in any other non-cash form) therefrom, in each case net of:

(1) all legal, accounting, investment banking, title and recording tax expenses, commissions and other fees and expenses Incurred, and all Federal, state, provincial, foreign and local taxes required to be paid or accrued as a liability under GAAP (after taking into account any available tax credits or deductions and any tax sharing agreements), as a consequence of such Asset Disposition;

(2) all payments made on any Indebtedness which is secured by any assets subject to such Asset Disposition, in accordance with the terms of any Lien upon such assets, or which must by its terms, or in order to obtain a necessary consent to such Asset Disposition, or by applicable law be repaid out of the proceeds from such Asset Disposition;

(3) all distributions and other payments required to be made to Minority Interest holders in Subsidiaries or joint ventures as a result of such Asset Disposition; and

(4) amounts accrued in accordance with GAAP in respect of liabilities associated with the assets disposed of in such Asset Disposition and retained by the Company or any Restricted Subsidiary after such Asset Disposition or liabilities incurred in connection with such Asset Disposition.

“ Net Cash Proceeds ,” with respect to any issuance or sale of Capital Stock, means the cash proceeds of such issuance or sale net of attorneys’ fees, accountants’ fees, underwriters’ or placement agents’ fees, listing fees, discounts or commissions and brokerage, consultant and other fees and charges actually Incurred in connection with such issuance or sale and net of taxes paid or payable as a result of such issuance or sale (after taking into account any available tax credit or deductions and any tax sharing arrangements).

“ Net Working Capital ” means (a) all current assets of the Company and its Restricted Subsidiaries except current assets under Commodity Agreements, less (b) all current liabilities of the Company and its Restricted Subsidiaries, except current liabilities included in Indebtedness and any current liabilities under Commodity Agreements, in each case as set forth in the consolidated financial statements of the Company prepared in accordance with GAAP.

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“ Non-Recourse Debt ” means Indebtedness of a Person:

(1) as to which neither the Company nor any Restricted Subsidiary (a) provides any Guarantee or credit support of any kind (including any undertaking, guarantee, indemnity, agreement or instrument that would constitute Indebtedness) or (b) is directly or indirectly liable (as a guarantor or otherwise);

(2) no default with respect to which (including any rights that the holders thereof may have to take enforcement action against an Unrestricted Subsidiary) would permit (upon notice, lapse of time or both) any holder of any other Indebtedness of the Company or any Restricted Subsidiary to declare a default under such other Indebtedness or cause the payment thereof to be accelerated or payable prior to its stated maturity; and

(3) the explicit terms of which provide there is no recourse against any of the assets of the Company or its Restricted Subsidiaries.

“ Oil and Gas Business ” means (a) the business of acquiring, exploring, exploiting, developing, producing, operating and disposing of interests in oil, gas, liquid natural gas and other hydrocarbon properties, (b) the business of gathering, marketing, treating, processing, storing, refining, selling and transporting any production from such interests or properties and products produced therefrom or in association therewith, and (c) any business or activity relating to, arising from, or necessary, appropriate or incidental to the activities described in the foregoing clauses (a) and (b) of this definition, including, without limitation, contract drilling, other oilfield services and alternative energy.

“ Oil and Gas Properties ” means all properties, including equity or other ownership interests therein, owned by such Person which contain or are believed to contain “proved oil and gas reserves” as defined in Rule 4-10 of Regulation S-X of the Securities Act.

“ Opinion of Counsel ” means a written opinion from legal counsel who is acceptable to the Trustee. The counsel may be an employee of or counsel to the Company or the Trustee.

“ Pari Passu Indebtedness ” means Indebtedness that ranks equally in right of payment to the Notes.

“ Permitted Business Investment ” means any Investment made in the ordinary course of the business of the Company or any Restricted Subsidiary or that is of a kind or character that is customarily made in the conduct of the Oil and Gas Business, including investments or expenditures for actively exploiting, exploring for, acquiring, developing, producing, processing, refining, gathering, marketing or transporting Hydrocarbons through agreements, transactions, interests or arrangements which permit one to share risks or costs, comply with regulatory requirements regarding local ownership or satisfy other objectives customarily achieved through the conduct of the Oil and Gas Business jointly with third parties, including:

(1) ownership interests in oil and gas properties, liquid natural gas facilities, refineries, drilling operations, processing facilities, gathering systems, pipelines or ancillary real property interests; and

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(2) Investments in the form of or pursuant to oil and gas leases, operating agreements, gathering agreements, processing agreements, farm-in agreements, farm-out agreements, development agreements, area of mutual interest agreements, unitization or pooling designations, declarations, orders and agreements, gas balancing or deferred production agreements, joint bidding agreements, service contracts, joint venture agreements, partnership agreements (whether general or limited), subscription agreements, stock purchase agreements and other similar agreements (including for limited liability companies) with third parties.

“ Permitted Distribution ” means a dividend or distribution, on one occasion and not more than one occasion, to holders of shares of the Company’s Capital Stock of shares of Capital Stock of Unit Drilling Company or any successor to the business thereof (the “Drilling Subsidiary”); provided that the portion of Consolidated EBITDA contributed by the Drilling Subsidiary (calculated assuming the Drilling Subsidiary and all of its subsidiaries are Restricted Subsidiaries) for the four full fiscal quarters immediately preceding the effective time of such dividend or distribution shall not exceed 30%.

“ Permitted Investment ” means an Investment by the Company or any Restricted Subsidiary in:

(1) the Company or a Restricted Subsidiary; provided , however , that the primary business of such Restricted Subsidiary is the Oil and Gas Business;

(2) another Person if as a result of such Investment such other Person becomes a Restricted Subsidiary or is merged or consolidated with or into, or transfers or conveys all or substantially all its assets to, the Company or a Restricted Subsidiary and in each case any Investment held by such Person; provided , however , that such Person’s primary business is the Oil and Gas Business;

(3) cash and Cash Equivalents;

(4) receivables owing to the Company or any Restricted Subsidiary created or acquired in the ordinary course and payable or dischargeable in accordance with customary trade terms; provided , however , that such trade terms may include such concessionary trade terms as the Company or any such Restricted Subsidiary deems reasonable under the circumstances;

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(5) payroll, travel and similar advances to cover matters that are expected at the time of such advances ultimately to be treated as expenses for accounting purposes and that are made in the ordinary course of business;

(6) loans or advances to employees and directors made in the ordinary course of business of the Company or such Restricted Subsidiary;

(7) Capital Stock, obligations or securities received in settlement of debts created in the ordinary course of business and owing to the Company or any Restricted Subsidiary or in satisfaction of judgments or pursuant to any plan of reorganization or similar arrangement upon the bankruptcy or insolvency of a debtor;

(8) Investments made as a result of the receipt of non-cash consideration from an Asset Disposition that was made pursuant to and in compliance with Section 3.07 of this First Supplemental Indenture;

(9) Investments in existence on the Issue Date or made pursuant to agreements or commitments in effect on the Issue Date;

(10) Commodity Agreements, Currency Agreements, Interest Rate Agreements and related Hedging Obligations, which transactions or obligations are Incurred in compliance with Section 3.02 of this First Supplemental Indenture;

(11) Guarantees made in accordance with Section 3.02 of this First Supplemental Indenture;

(12) Permitted Business Investments in an aggregate amount not to exceed 5% of Adjusted Consolidated Net Tangible Assets (with Adjusted Consolidated Net Tangible Assets and the fair market value of such Investment being measured at the time such Investment is made and without giving effect to subsequent changes in value);

(13) any Person to the extent such Investments consist of prepaid expenses, negotiable instruments held for collection and lease, utility and workers’ compensation, performance and other similar deposits made in the ordinary course of business by the Company or any Restricted Subsidiary;

(14) any Asset Swap; and

(15) acquisitions of assets, Equity Interests or other securities by the Company for consideration consisting solely of common equity securities of the Company.

In order to be a Permitted Investment, an Investment need not be permitted solely by one subsection of this definition but may be permitted in part of one such subsection and in part by one or more other subsections of this definition. In the event an Investment meets the criteria of one or more of the subsections of this definition, the Company, in its sole discretion, may classify all or any portion of such Investment as being permitted by any one or more of such subsections.

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“ Permitted Liens ” means, with respect to any Person:

(1) Liens securing Indebtedness and other obligations under a Credit Facility, including the Senior Credit Agreement and related Hedging Obligations and other Senior Indebtedness and liens on assets of Restricted Subsidiaries securing Guarantees of Indebtedness and other obligations of the Company under a Credit Facility and other Guarantor Senior Indebtedness permitted to be Incurred under the Indenture under clause (1) of the second paragraph under Section 3.02 of this First Supplemental Indenture;

(2) pledges or deposits by such Person under workmen’s compensation laws, unemployment insurance laws or similar legislation, or earnest money, good faith or similar deposits in connection with bids, tenders, contracts (other than for the payment of Indebtedness) or leases to which such Person is a party, or deposits to secure public, regulatory or statutory obligations of such Person or deposits of cash or Cash Equivalents to secure surety or appeal bonds to which such Person is a party, or deposits as security for contested taxes or import or customs duties or for the payment of rent, in each case Incurred in the ordinary course of business;

(3) Liens imposed by law, including carriers’, warehousemen’s, suppliers’, materialmen’s and mechanics’ Liens, in each case for sums not yet due or being contested in good faith by appropriate proceedings if appropriate reserves or other provisions required by GAAP, if any, shall have been made in respect thereof;

(4) Liens for taxes, assessments or other governmental charges not yet subject to penalties for non-payment or which are being contested in good faith by appropriate proceedings if appropriate reserves or other provisions required by GAAP shall have been made in respect thereof;

(5) Liens in favor of issuers of surety or performance bonds or letters of credit or bankers’ acceptances issued pursuant to the request of and for the account of such Person in the ordinary course of its business;

(6) survey exceptions, encumbrances, ground leases, easements or reservations of, or rights of others for, licenses, rights of way, servitudes, permits, sewers, electric lines, telegraph and telephone lines and other similar purposes, or zoning, building codes or surface leases and other similar rights in respect of surface operations or other restrictions (including, without limitation, minor defects or irregularities in title and similar encumbrances) as to the use of real properties or liens incidental to the conduct of the business of such Person or to the ownership of its properties which do not in the aggregate materially adversely affect the value of the assets of such Person and its Restricted Subsidiaries, taken as a whole or materially impair their use in the operation of the business of such Person;

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(7) Liens securing Hedging Obligations;

(8) leases, licenses, subleases and sublicenses of assets (including, without limitation, real property and intellectual property rights) which do not materially interfere with the ordinary conduct of the business of the Company or any of its Restricted Subsidiaries;

(9) judgment Liens not giving rise to an Event of Default so long as such Lien is adequately bonded and any appropriate legal proceedings which may have been duly initiated for the review of such judgment have not been finally terminated or the period within which such proceedings may be initiated has not expired;

(10) Liens for the purpose of securing the payment of all or a part of the purchase price of, or Capital Lease Obligations, purchase money obligations or other payments Incurred to finance the acquisition, lease, improvement or construction of or repairs or additions to, assets or property acquired or constructed in the ordinary course of business; provided that:

(11) Liens arising solely by virtue of any statutory or common law provisions relating to banker’s Liens, rights of set-off or similar rights and remedies as to deposit accounts or other funds maintained with a depositary institution; provided that:

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(12) Liens arising from Uniform Commercial Code financing statement filings regarding operating leases entered into by the Company and its Restricted Subsidiaries in the ordinary course of business;

(13) Liens existing on the Issue Date;

(14) Liens on property or shares of stock of a Person at the time such Person becomes a Restricted Subsidiary; provided , however , that such Liens are not created, Incurred or assumed in connection with, or in contemplation of, such other Person becoming a Restricted Subsidiary; provided further, however, that any such Lien may not extend to any other property owned by the Company or any Restricted Subsidiary;

(15) Liens on property at the time the Company or a Restricted Subsidiary acquired the property, including any acquisition by means of a merger or consolidation with or into the Company or any Restricted Subsidiary; provided , however , that such Liens are not created, Incurred or assumed in connection with, or in contemplation of, such acquisition; provided further, however, that such Liens may not extend to any other property owned by the Company or any Restricted Subsidiary;

(16) Liens securing Indebtedness or other obligations of a Restricted Subsidiary owing to the Company or a Wholly-Owned Subsidiary;

(17) Liens securing the Notes and Subsidiary Guarantees;

(18) Liens securing Refinancing Indebtedness Incurred to refinance Indebtedness that was previously so secured, provided that any such Lien is limited to all or part of the same property or assets (plus improvements, accessions, proceeds or dividends or distributions in respect thereof) that secured (or, under the written arrangements under which the original Lien arose, could secure) the Indebtedness being refinanced or is in respect of property that is the security for a Permitted Lien hereunder;

(19) any interest or title of a lessor under any Capital Lease Obligation or operating lease;

(20) Liens in respect of Production Payments and Reserve Sales, which Liens shall be limited to the oil and gas property or other interest that is subject to such Production Payments and Reserve Sales;

(21) Liens arising under oil and gas leases, farm-out agreements, farm-in agreements, division orders, contracts for the sale, purchase, exchange, transportation, gathering or processing of Hydrocarbons, partnership agreements, joint venture agreements, unitizations and pooling designations, declarations, orders and agreements, development agreements, operating agreements, production sales contracts, area of mutual interest agreements, gas balancing or

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deferred production agreements, injection, repressuring and recycling agreements, salt water or other disposal agreements, seismic or geophysical permits or agreements, and other agreements which are customary in the Oil and Gas Business; provided , however , in all instances that such Liens are limited to the assets that are subject to the relevant agreement, program, order or contract;

(22) Liens on pipelines or pipeline facilities that arise by operation of law;

(23) Liens securing Indebtedness (other than Subordinated Obligations and Guarantor Subordinated Obligations) in an aggregate principal amount outstanding at any one time not to exceed the greater of $30 million or 2% of the Company’s Adjusted Consolidated Net Tangible Assets, as determined on the date of Incurrence of this Indebtedness after giving pro forma effect to the Incurrence and the application of the proceeds therefrom;

(24) Liens in favor of the Company or any Subsidiary Guarantor;

(25) Deposits made in the ordinary course of business to secure liability to insurance carriers;

(26) any (a) interest or title of a lessor or sublessor under any lease, liens reserved in oil, gas or other Hydrocarbons, minerals, leases for bonus, royalty or rental payments and for compliance with the terms of such leases; (b) restriction or encumbrance that the interest or title of such lessor or sublessor may be subject to (including, without limitation, ground leases or other prior leases of the demised premises, mortgages. mechanics’ liens, tax liens, and easements); or (c) subordination of the interest of the lessee or sublessee under such lease to any restrictions or encumbrance referred to in the preceding clause (b);

(27) Liens arising under the Indenture in favor of the Trustee for its own benefit and similar Liens in favor of other trustees, agents and representatives arising under instruments governing Indebtedness permitted to be incurred under the Indenture, provided, however, that such Liens are solely for the benefit of the trustees, agents or representatives in their capacities as such and not for the benefit of the holders of such Indebtedness; and

(28) Liens in favor of collecting or payer banks having a right of setoff, revocation, or charge back with respect to money or instruments of the Company or any Subsidiary of the Company on deposit with or in possession of such bank.

In each case set forth above, notwithstanding any stated limitation on the assets that may be subject to such Lien, a Permitted Lien on a specified asset or group or type of assets may include Liens on all improvements, additions and accessions thereto and all products and proceeds thereof (including dividends, distributions and increases in respect thereof).

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“ Person ” means any individual, partnership, corporation, limited liability company, joint stock company, business trust, trust, unincorporated association, joint venture, or other entity, or government or political subdivision or agency.

“ Preferred Stock ,” as applied to the Capital Stock of any corporation, means Capital Stock of any class or classes (however designated) which is preferred as to the payment of dividends, or as to the distribution of assets upon any voluntary or involuntary liquidation or dissolution of such corporation, over shares of Capital Stock of any other class of such corporation.

“ Production Payments and Reserve Sales ” means the grant or transfer by the Company or a Restricted Subsidiary to any Person of a royalty, overriding royalty, net profits interest, production payment (whether volumetric or dollar denominated), partnership or other interest in oil and gas properties or the right to receive all or a portion of the production or the proceeds from the sale of production attributable to such properties, where the grantee or transferee thereof has recourse solely to such production or proceeds of production, subject to the obligation of the grantor or transferor to operate and maintain, or cause to be operated and maintained, the related oil and gas properties or other related interests in a reasonably prudent manner or other customary standard or subject to the obligation of the grantor or transferor to indemnify for environmental, title or other matters customary in the Oil and Gas Business, including any such grants or transfers pursuant to incentive compensation programs on terms that are reasonably customary in the Oil and Gas Business for geologists, geophysicists or other providers of technical services to the Company or a Restricted Subsidiary.

“ Rating Agency ” means S&P and Moody’s or if S&P or Moody’s or both shall not make a rating on the Notes publicly available, a nationally recognized statistical rating agency or agencies, as the case may be, selected by the Company (as certified by a resolution of the Board of Directors or a committee thereof) which shall be substituted for S&P or Moody’s or both, as the case may be.

“ Receivables ” means a right to receive payment arising from a sale or lease of goods or the performance of services by a Person pursuant to an arrangement with another Person pursuant to which such other Person is obligated to pay for goods or services under terms that permit the purchase of such goods and services on credit and shall include, in any event, any items of property that would be classified as an “account,” “chattel paper,” “payment intangible” or “instrument” under the Uniform Commercial Code as in effect in the State of New York and any “supporting obligations” as so defined.

“ Receivables Fees ” means any fees or interest paid to purchasers or lenders providing the financing in connection with a factoring agreement or other similar agreement, including any such amounts paid by discounting the face amount of Receivables or participations therein transferred in connection with a factoring agreement or other similar arrangement, regardless of whether any such transaction is structured as on-balance sheet or off-balance sheet or through a Restricted Subsidiary or an Unrestricted Subsidiary.

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“ Refinancing Indebtedness ” means Indebtedness that is Incurred to refund, refinance, replace, exchange, renew, repay or extend (including pursuant to any defeasance or discharge mechanism) (collectively, “ refinance ,” “ refinances ,” and “ refinanced ” shall have a correlative meaning) any Indebtedness existing on the Issue Date or Incurred in compliance with the Indenture (including Indebtedness of the Company that refinances Indebtedness of any Restricted Subsidiary and Indebtedness of any Restricted Subsidiary that refinances Indebtedness of another Restricted Subsidiary) including Indebtedness that refinances Refinancing Indebtedness, provided , however , that:

(1)(a) if the Stated Maturity of the Indebtedness being refinanced is earlier than the Stated Maturity of the Notes, the Refinancing Indebtedness has a Stated Maturity no earlier than the Stated Maturity of the Indebtedness being refinanced or (b) if the Stated Maturity of the Indebtedness being refinanced is later than the Stated Maturity of the Notes, the Refinancing Indebtedness has a Stated Maturity at least 91 days later than the Stated Maturity of the Notes;

(2) the Refinancing Indebtedness has an Average Life at the time such Refinancing Indebtedness is Incurred that is equal to or greater than the Average Life of the Indebtedness being refinanced;

(3) such Refinancing Indebtedness is Incurred in an aggregate principal amount (or if issued with original issue discount, an aggregate issue price) that is equal to or less than the sum of the aggregate principal amount (or if issued with original issue discount, the aggregate accreted value) then outstanding of the Indebtedness being refinanced (plus, without duplication, any additional Indebtedness Incurred to pay interest or premiums required by the instruments governing such existing Indebtedness and fees and expenses Incurred in connection therewith); and

(4) if the Indebtedness being refinanced is subordinated in right of payment to the Notes or the Subsidiary Guarantee, such Refinancing Indebtedness is subordinated in right of payment to the Notes or the Subsidiary Guarantee on terms at least as favorable to the holders as those contained in the documentation governing the Indebtedness being extended, refinanced, renewed, replaced, defeased or refunded.

“ Regular Record Date ” means, with respect to each Interest Payment Date, the close of business on the immediately preceding May1 or November 1, as the case may be.

“ Representative ” means any trustee, agent or representative (if any) of an issue of Senior Indebtedness; provided that when used in connection with the Senior Credit Agreement, the term “ Representative ” shall refer to the global administrative agent under the Senior Credit Agreement.

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“ Restricted Investment ” means any Investment other than a Permitted Investment.

“ Restricted Subsidiary ” means any Subsidiary of the Company other than an Unrestricted Subsidiary.

“ S&P ” means Standard & Poor’s Ratings Services, a division of The McGraw-Hill Companies, Inc., and its successors.

“ Sale/Leaseback Transaction ” means an arrangement relating to property now owned or hereafter acquired whereby the Company or a Restricted Subsidiary transfers such property to a Person and the Company or a Restricted Subsidiary leases it from such Person.

“ Senior Indebtedness ” means, whether outstanding on the Issue Date or thereafter issued, created, Incurred or assumed, the Bank Indebtedness and all amounts payable by the Company under or in respect of all other Indebtedness of the Company, including premiums and accrued and unpaid interest (including interest accruing on or after the filing of any petition in bankruptcy or for reorganization relating to the Company at the rate specified in the documentation with respect thereto whether or not a claim for post-filing interest is allowed in such proceeding) and fees relating thereto; provided , however , that Senior Indebtedness will not include:

(1) any Indebtedness Incurred in violation of the Indenture;

(2) any obligation of the Company to any Subsidiary;

(3) any liability for Federal, state, foreign, local or other taxes owed or owing by the Company;

(4) any accounts payable or other liability to trade creditors arising in the ordinary course of business (including Guarantees thereof or instruments evidencing such liabilities);

(5) any Indebtedness, Guarantee or obligation of the Company that is expressly subordinate or junior in right of payment to any other Indebtedness, Guarantee or obligation of the Company, including, without limitation, any Senior Subordinated Indebtedness and any Subordinated Obligations; or

(6) any Capital Stock.

“ Senior Credit Agreement ” means the First Amended and Restated Senior Credit Agreement, dated May 24, 2007, as amended December 23, 2008, among Unit Corporation, Superior Pipeline Company, L.L.C., Unit Drilling

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Company, Unit Petroleum Company, and Unit Texas Drilling, L.L.C., as Borrowers, The Lenders, Bank of Oklahoma, National Association, as Administrative Agent for the Lenders and as Co-Arranger, Bank of America, National Association, as Co-Arranger, BMO Capital Markets Financing, Inc., as Syndication Agent and Compass Bank, as Documentation Agent.

“ Senior Subordinated Indebtedness ” means the Notes and any other Indebtedness of the Company that specifically provides that such Indebtedness is to rank equally with the Notes in right of payment and is not subordinated by its terms in right of payment to any Indebtedness or other obligation of the Company which is not Senior Indebtedness.

“ Significant Subsidiary ” means any Restricted Subsidiary that would be a “ Significant Subsidiary ” of the Company within the meaning of Rule 1-02 under Regulation S-X promulgated by the SEC.

“ Stated Maturity ” means, with respect to any security, the date specified in such security as the fixed date on which the payment of principal of such security is due and payable, including pursuant to any mandatory redemption provision, but shall not include any contingent obligations to repay, redeem or repurchase any such principal prior to the date originally scheduled for the payment thereof.

“ Subordinated Obligation ” means any Indebtedness of the Company (whether outstanding on the Issue Date or thereafter Incurred) that is subordinate or junior in right of payment to the Notes pursuant to a written agreement.

“ Subsidiary ” of any Person means (a) any corporation, association or other business entity (other than a partnership, joint venture, limited liability company or similar entity) of which more than 50% of the total ordinary voting power of shares of Capital Stock entitled (without regard to the occurrence of any contingency) to vote in the election of directors, managers or trustees thereof (or persons performing similar functions) or (b) any partnership, joint venture limited liability company or similar entity of which more than 50% of the capital accounts, distribution rights, total equity and voting interests or general or limited partnership interests, as applicable, is, in the case of clauses (a) and (b), at the time owned or controlled, directly or indirectly, by (1) such Person, (2) such Person and one or more Subsidiaries of such Person, or (3) one or more Subsidiaries of such Person. Unless otherwise specified herein, each reference to a Subsidiary will refer to a Subsidiary of the Company.

“ Subsidiary Guarantee ” means, individually, any Guarantee of payment of the Notes by a Subsidiary Guarantor pursuant to the terms of the Indenture and any supplemental indenture thereto, and, collectively, all such Guarantees. Each such Subsidiary Guarantee will be in the form prescribed by the Indenture.

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“ Subsidiary Guarantor ” means (i) each of Unit Drilling Company, Unit Petroleum Company, Superior Pipeline Company, L.L.C., Unit Texas Drilling, L.L.C., Unit Drilling USA Colombia, L.L.C., Unit Drilling Colombia, L.L.C., Unit Texas Company, Superior Pipeline Texas, L.L.C., Superior Appalachian Pipeline, L.L.C., Unit Drilling and Exploration Company, Petroleum Supply Company and Preston County Gas Gathering, L.L.C. and (ii) any Restricted Subsidiary (other than a Foreign Subsidiary) created or acquired by the Company or one or more of its Restricted Subsidiaries after the Issue Date.

“ Treasury Rate ” means the yield to maturity at the time of computation of United States Treasury securities with a constant maturity (as compiled and published in the most recent Federal Reserve Statistical Release H.15 (519) which has become publicly available at least two business days prior to the Redemption Date (or, if such Statistical Release is no longer published, any publicly available source or similar market data)) most nearly equal to the period from the Redemption Date to May 15, 2016; provided , however , that if the period from the Redemption Date to May 15, 2016 is not equal to the constant maturity of a United States Treasury security for which a weekly average yield is given, the Treasury Rate shall be obtained by linear interpolation (calculated to the nearest one-twelfth of a year) from the weekly average yields of United States Treasury securities for which such yields are given, except that if the period from the Redemption Date to May 15, 2016 is less than one year, the weekly average yield on actually traded United States Treasury securities adjusted to a constant maturity of one year shall be used.

“ Unrestricted Subsidiary ” means

(1) any Subsidiary of the Company that at the time of determination shall be designated an Unrestricted Subsidiary by the Board of Directors of the Company in the manner provided below; and

(2) any Subsidiary of an Unrestricted Subsidiary.

The Board of Directors of the Company may designate any Subsidiary of the Company (including any newly acquired or newly formed Subsidiary or a Person becoming a Subsidiary through merger or consolidation or Investment therein) to be an Unrestricted Subsidiary only if:

(1) such Subsidiary or any of its Subsidiaries does not own any Capital Stock or Indebtedness of or have any Investment in, or own or hold any Lien on any property of, any other Subsidiary of the Company which is not a Subsidiary of the Subsidiary to be so designated or otherwise an Unrestricted Subsidiary;

(2) all the Indebtedness of such Subsidiary and its Subsidiaries shall, at the date of designation and at all times thereafter, consist of Non-Recourse Debt;

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(3) such designation and the Investment of the Company in such Subsidiary complies with Section 3.04 of this First Supplemental Indenture;

(4) such Subsidiary, either alone or in the aggregate with all other Unrestricted Subsidiaries, does not operate, directly or indirectly, all or substantially all of the business of the Company and its Subsidiaries;

(5) such Subsidiary is a Person with respect to which neither the Company nor any of its Restricted Subsidiaries has any direct or indirect obligation:

(6) on the date such Subsidiary is designated an Unrestricted Subsidiary, such Subsidiary is not a party to any agreement, contract, arrangement or understanding with the Company or any Restricted Subsidiary with terms materially less favorable to the Company than those that might have been reasonably obtained from Persons that are not Affiliates of the Company.

Any such designation by the Board of Directors of the Company shall be evidenced to the Trustee by filing with the Trustee a resolution of the Board of Directors of the Company giving effect to such designation and an Officers’ Certificate certifying that such designation complies with the foregoing conditions. If, at any time, any Unrestricted Subsidiary would fail to meet the foregoing requirements as an Unrestricted Subsidiary, it shall thereafter cease to be an Unrestricted Subsidiary for purposes of the Indenture and any Indebtedness of such Subsidiary shall be deemed to be Incurred as of such date.

The Board of Directors of the Company may designate any Unrestricted Subsidiary to be a Restricted Subsidiary; provided that immediately after giving effect to such designation, no Default or Event of Default shall have occurred and be continuing or would occur as a consequence thereof and the Company could Incur at least $1.00 of additional Indebtedness under the first paragraph of Section 3.02 of this First Supplemental Indenture on a pro forma basis taking into account such designation.

“ U.S. Government Obligations ” means securities that are (a) direct obligations of the United States of America for the timely payment of which its full faith and credit is pledged or (b) obligations of a Person controlled or supervised by and acting as an agency or instrumentality of the United States of America the timely payment of which is unconditionally guaranteed as a full faith and credit obligation of the United States of America, which, in either case, are not callable or redeemable at the option of the issuer thereof, and shall also

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include a depositary receipt issued by a bank (as defined in Section 3(a)(2) of the Securities Act), as custodian with respect to any such U.S. Government Obligations or a specific payment of principal of or interest on any such U.S. Government Obligations held by such custodian for the account of the holder of such depositary receipt; provided that (except as required by law) such custodian is not authorized to make any deduction from the amount payable to the holder of such depositary receipt from any amount received by the custodian in respect of the U.S. Government Obligations or the specific payment of principal of or interest on the U.S. Government Obligations evidenced by such depositary receipt.

“ Underwriters ” means Merrill Lynch, Pierce, Fenner & Smith Incorporated, BMO Capital Markets Corp., Banco Bilbao Vizcaya Argentaria, S.A., BNP Paribas Securities Corp., Comerica Securities, Inc., Credit Agricole Securities (USA) Inc., Bosc, Inc., and BB&T Capital Markets, a division of Scott & Stringfellow, LLC.

“ Volumetric Production Payments ” means production payment obligations recorded as deferred revenue in accordance with GAAP, together with all undertakings and obligations in connection therewith.

“ Voting Stock ” of a corporation means all classes of Capital Stock of such corporation then outstanding and normally entitled to vote in the election of directors.

“ Wholly-Owned Subsidiary ” means a Restricted Subsidiary, all of the Capital Stock of which (other than directors’ qualifying shares) is owned by the Company or another Wholly-Owned Subsidiary.

Section 1.03 . Payment of Principal and Interest. The principal of the Notes shall be due at Stated Maturity (unless earlier redeemed). The unpaid principal amount of the Notes shall bear interest at the rate of 6.625% per year until paid or duly provided for, such interest to accrue from May 18, 2011 or from the most recent Interest Payment Date to which interest has been paid or duly provided for. Interest shall be paid semi-annually in arrears on each Interest Payment Date, commencing November 15, 2011, to the Person or Persons in whose name a Note is registered at the close of business on the Regular Record Date for such Interest Payment Date, provided that interest payable at the Stated Maturity or on a Redemption Date as provided herein will be paid to the Person to whom principal is payable. Any such interest that is not so punctually paid or duly provided for will forthwith cease to be payable to the Holders on such Regular Record Date and may either be paid to the Person in whose name the Note (or one or more Predecessor Securities) is registered at the close of business on a Special Record Date for the payment of such Defaulted Interest to be fixed by the Trustee, notice whereof shall be given to Holders of the Notes not less than 10 calendar days prior to such Special Record Date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Notes may be listed, and upon such notice as may be required by such exchange, all as more fully provided in the Original Indenture.

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Payments of interest on the Notes will include interest accrued to but excluding the respective Interest Payment Dates. Interest payments for the Notes shall be computed and paid on the basis of a 360-day year consisting of twelve 30-day months. In the event that any date on which interest is payable on the Notes is not a Business Day, then payment of the interest payable on such date will be made on the next succeeding day that is a Business Day (and without any interest or other payment in respect of any such delay), except that, if such Business Day is in the next succeeding calendar year, such payment shall be made on the immediately preceding Business Day, in each case with the same force and effect as if made on the date the payment was originally payable.

Subject, in the case of any Global Security, to any applicable requirements of the Depositary, payment of the principal, premium, if any, and interest due at the Stated Maturity of, or on a Redemption Date for, the Notes shall be made upon surrender of the Notes at the Corporate Trust Office of the Paying Agent. The principal of and interest on the Notes shall be paid in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts. Payments of interest (including interest on any Interest Payment Date) will be made, subject to such surrender where applicable, at the option of the Company, (i) by check mailed to the address of the Person entitled thereto as such address shall appear in the Security Register or (ii) by wire transfer at such place and to such account at a banking institution in the United States as may be designated in writing to the Trustee at least 15 days prior to the date for payment by the Person entitled thereto.

Section 1.04 . Denominations. The Notes may be issued in minimum denominations of $2,000, or integral multiples of $1,000 in excess thereof.

Section 1.05 . Global Securities. The Notes will be initially issued in the form of one or more Global Securities registered in the name of the Depositary (which initially shall be The Depository Trust Company) or its nominee. Except under the limited circumstances described below, Notes represented by such Global Securities will not be exchangeable for, and will not otherwise be issuable as, Notes in definitive form. The Global Securities described above may not be transferred except by the Depositary to a nominee of the Depositary or by a nominee of the Depositary to the Depositary or another nominee of the Depositary or to a successor Depositary or its nominee.

Owners of beneficial interests in such Global Securities will not be considered the Holders thereof for any purpose under the Indenture, and no Global Security representing a Note shall be exchangeable, except for another Global Security of like denomination and tenor to be registered in the name of the Depositary or its nominee or to a successor Depositary or its nominee. The rights of holders of beneficial interests in such Global Securities shall be exercised only through the Depositary.

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A Global Security shall be exchangeable for Notes registered in the names of Persons other than the Depositary or its nominee only as provided by Section 2.05 of the Original Indenture. Any Global Security that is exchangeable pursuant to the preceding sentence shall be exchangeable for Notes registered in such names as the Depositary shall direct.

Section 1.06 . Transfer. No service charge will be made for any registration of transfer or exchange of Notes, but the Company may require payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in connection therewith.

Section 1.07 . Defeasance. The provisions of Article 11 of the Original Indenture will apply to the Notes.

Section 1.08 . Redemption at the Option of the Company.

(a) Except as described in this Section 1.08, the Notes are not redeemable until May 15, 2016. On and after May 15, 2016, the Company may redeem all or, from time to time, a part of the Notes upon not less than 30 nor more than 60 days’ notice, at the following Redemption Prices (expressed as a percentage of principal amount) plus accrued and unpaid interest on the Notes, if any, to the applicable Redemption Date (subject to the right of Holders of record on the relevant Regular Record Date to receive interest due on the relevant Interest Payment Date), if redeemed during the twelve-month period beginning on May 15 of the years indicated below:

(b) Prior to May 15, 2014, the Company may on any one or more occasions redeem up to 35% of the original principal amount of the Notes with the Net Cash Proceeds of one or more equity offerings at a Redemption Price of 106.625% of the principal amount thereof, plus accrued and unpaid interest, if any, to the Redemption Date (subject to the right of Holders of record on the relevant Regular Record Date to receive interest due on the relevant Interest Payment Date); provided that:

(i) at least 65% of the original principal amount of the Notes remains outstanding after each such redemption; and

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(ii) the redemption occurs within 90 days after the closing of such equity offering.

(c) In addition, at any time prior to May 15, 2016, the Company may redeem the Notes, in whole or in part, at a Redemption Price equal to 100% of the principal amount thereof plus the Applicable Premium plus accrued and unpaid interest, if any, to the Redemption Date (subject to the right of Holders of record on the relevant Regular Record Date to receive interest due on the relevant Interest Payment Date).

(d) If the optional Redemption Date is on or after a Regular Record Date and on or before the related Interest Payment Date, the accrued and unpaid interest, if any, will be paid to the Person in whose name the Note is registered at the close of business on the Regular Record Date, and no additional interest will be payable to Holders whose Notes will be subject to redemption.

(e) In the case of any partial redemption, selection of the Notes for redemption will be made by the Trustee:

(i) in compliance with the requirements of the principal national securities exchange, if any, on which the Notes are listed (to the extent such listing is known to the Trustee); or

(ii) if the Notes are not listed, then on a pro rata basis, by lot or by such other method as the Trustee in its sole discretion may deem to be fair and appropriate.

No Note of $2,000 in original principal amount or less will be redeemed in part. If any Note is to be redeemed in part only, the notice of redemption relating to such Note will state the portion of the principal amount thereof to be redeemed. A new Note in principal amount equal to the unredeemed portion thereof will be issued in the name of the Holder upon cancellation of the original Note.

(f) The Company shall notify the Trustee of the Redemption Price with respect to the redemption promptly after the calculation thereof. The Trustee shall not be responsible for calculating the Redemption Price.

Section 1.09 . Paying Agent. The Trustee shall initially serve as Paying Agent with respect to the Notes, with the place of payment initially being the corporate trust office of the Trustee.

Section 1.10 . Additional Notes. Subject to the terms and conditions contained herein, the Company may from time to time, without the consent of the existing Holders of Notes create and issue additional notes (the “ Additional Notes ”) having the same terms and conditions as the Notes in all respects, except for issue date, issue price and the first payment of interest thereon. Such Additional Notes, at the Company’s determination and in accordance with the

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provisions of the Indenture, will be consolidated with and form a single series with the previously outstanding Notes for all purposes of the Indenture, including, without limitation, amendments, waivers, and redemptions. The aggregate principal amount of the Additional Notes, if any, shall be unlimited.

ARTICLE 2

S UBSIDIARY G UARANTEES

Section 2.01 . Guarantee.

(a) Subject to this Article 2, each of the Subsidiary Guarantors hereby, jointly and severally, fully and unconditionally Guarantees, on a senior subordinated basis, to each Holder of a Note authenticated and delivered by the Trustee and to the Trustee and its successors and assigns, irrespective of the validity and enforceability of this Indenture, the Notes or the obligations of the Company hereunder or thereunder, that:

(i) the principal of, premium, if any, and interest on the Notes will be promptly paid in full when due, whether at Stated Maturity, by acceleration, redemption or otherwise, and interest on the overdue principal of and interest on the Notes, if any, if lawful, and all other obligations of the Company to the Holders or the Trustee hereunder or thereunder will be promptly paid in full or performed, all in accordance with the terms hereof and thereof, and

(ii) in case of any extension of time of payment or renewal of any Notes or any of such other obligations, that same will be promptly paid in full when due or performed in accordance with the terms of the extension or renewal, whether at Stated Maturity, by acceleration or otherwise.

Failing payment when due of any amount so guaranteed or any performance so guaranteed for whatever reason, the Subsidiary Guarantors will be jointly and severally obligated to pay the same immediately. Each Subsidiary Guarantor agrees that this is a guarantee of payment and not a guarantee of collection.

(b) The Subsidiary Guarantors hereby agree that their obligations hereunder are unconditional, irrespective of the validity, regularity or enforceability of the Notes or this Indenture, the absence of any action to enforce the same, any waiver or consent by any Holder with respect to any provisions hereof or thereof, the recovery of any judgment against the Company, any action to enforce the same or any other circumstance which might otherwise constitute a legal or equitable discharge or defense of a guarantor.

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(c) Each Subsidiary Guarantor hereby waives diligence, presentment, demand of payment, filing of claims with a court in the event of insolvency or bankruptcy of the Company, any right to require a proceeding first against the Company, protest, notice and all demands whatsoever and covenants that this Subsidiary Guarantee will not be discharged except by complete performance of the obligations contained in the Notes and the Indenture.

(d) If any Holder or the Trustee is required by any court or otherwise to return to the Company, the Subsidiary Guarantors or any custodian, trustee, liquidator or other similar official acting in relation to either the Company or the Subsidiary Guarantors, any amount paid by either to the Trustee or such Holder, this Subsidiary Guarantee, to the extent theretofore discharged, will be reinstated in full force and effect.

(e) Each Subsidiary Guarantor agrees that it will not be entitled to any right of subrogation in relation to the Holders in respect of any obligations guaranteed hereby until payment in full of all obligations guaranteed hereby. Each Subsidiary Guarantor further agrees that, as between the Subsidiary Guarantors, on the one hand, and the Holders and the Trustee, on the other hand, (1) the maturity of the obligations guaranteed hereby may be accelerated as provided in Article 4 hereof for the purposes of this Subsidiary Guarantee, notwithstanding any stay, injunction or other prohibition preventing such acceleration in respect of the obligations guaranteed hereby, and (2) in the event of any declaration of acceleration of such obligations as provided in Article 4 hereof, such obligations (whether or not due and payable) will forthwith become due and payable by the Subsidiary Guarantors for the purpose of this Subsidiary Guarantee.

(f) The Subsidiary Guarantors will have the right to seek contribution from any non-paying Subsidiary Guarantor so long as the exercise of such right does not impair the rights of the Holders under the Subsidiary Guarantee.

Section 2.02 . Limitation on Subsidiary Guarantor Liability. Each Subsidiary Guarantor, and by its acceptance of Notes, each Holder, hereby confirms that it is the intention of all such parties that the Subsidiary Guarantee of such Subsidiary Guarantor not constitute a fraudulent transfer or conveyance for purposes of Bankruptcy Law, the Uniform Fraudulent Conveyance Act, the Uniform Fraudulent Transfer Act or any similar federal or state law to the extent applicable to any Subsidiary Guarantee. To effectuate the foregoing intention, the Trustee, the Holders and the Subsidiary Guarantors hereby irrevocably agree that the obligations of such Subsidiary Guarantor will be limited to the maximum amount that will, after giving effect to such maximum amount and all other contingent and fixed liabilities of such Subsidiary Guarantor that are relevant under such laws, and after giving effect to any collections from, rights to receive contribution from or payments made by or on behalf of any other Subsidiary Guarantor in respect of the obligations of such other Subsidiary Guarantor under this Article 2, result in the obligations of such Subsidiary Guarantor under its Subsidiary Guarantee not constituting a fraudulent transfer or conveyance.

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Section 2.03 . Releases of Subsidiary Guarantees. The Subsidiary Guarantee of a Subsidiary Guarantor will be released:

(a) in connection with any sale, disposition or other transfer (including through merger or consolidation) (x) of the Capital Stock of such Subsidiary Guarantor following which such Subsidiary Guarantor is no longer a Subsidiary of the Company, (y) of all or substantially all the assets of the applicable Subsidiary Guarantor, in each case, to a Person that is not (either before or after giving effect to such transaction) the Company or a Restricted Subsidiary of the Company, and (z) following which the Subsidiary Guarantor is no longer a Restricted Subsidiary, if such sale, disposition or other transfer is made in compliance with the applicable provisions of this Indenture and all of the obligations of the Subsidiary Guarantor under any Credit Facility and related documentation and any other agreements relating to any other Indebtedness of the Company or its Restricted Subsidiaries terminate upon consummation of such transaction;

(b) in connection with the defeasance of the Notes and the Subsidiary Guarantees, to the extent that the obligations of the Company have been discharged thereby; or

(c) if the Company designates any Restricted Subsidiary that is a Subsidiary Guarantor as an Unrestricted Subsidiary in accordance with the applicable provisions of this Indenture.

ARTICLE 3

P ARTICULAR C OVENANTS OF THE C OMPANY WITH R ESPECT TO THE N OTES

Section 3.01 . Effectiveness of Covenants. From and after the first day on which:

(a) the Notes have an Investment Grade Rating from both of the Ratings Agencies; and

(b) no Default has occurred and is continuing under the Indenture;

the Company and its Restricted Subsidiaries will cease to be subject to Sections 3.02, 3.04, 3.06, 3.07, 3.08, 3.12, and clause (d) of Section 3.10 of this First Supplemental Indenture. (collectively, the “ Suspended Covenants ”). If at any time the credit rating of the Notes is downgraded from an Investment Grade Rating by either Rating Agency, then the Suspended Covenants will thereafter be reinstated and again be applicable pursuant to the terms of the Indenture, unless and until the Notes subsequently attain an Investment Grade Rating. Neither the failure of the Company or any of its Subsidiaries to comply with a Suspended Covenant after the Notes attain an Investment Grade Rating and before any reinstatement of the Suspended Covenants nor compliance by the Company or

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any of its Subsidiaries with any contractual obligation entered into in compliance with the Indenture during that period will constitute a Default, Event of Default or breach of any kind under the Indenture, the Notes or the Subsidiary Guarantees. The Trustee shall not have any obligation to monitor whether the commencement and termination of any period when the Suspended Covenants are suspended pursuant to this Section has occurred and shall not have any obligation to notify the Holders thereof.

During any period when the Suspended Covenants are not in effect, the Board of Directors of the Company may not designate any of the Company’s Subsidiaries as Unrestricted Subsidiaries pursuant to the Indenture.

Section 3.02 . Limitation on Indebtedness. The Company may not, and may not permit any of its Restricted Subsidiaries to, Incur any Indebtedness (including Acquired Indebtedness); except, that the Company and any Subsidiary Guarantor may Incur Indebtedness if on the date thereof:

(a) the Consolidated Coverage Ratio for the Company and its Restricted Subsidiaries is at least 2.25 to 1.0; and

(b) no Default or Event of Default shall have occurred and be continuing or would occur as a consequence of Incurring the Indebtedness or the transactions relating to such Incurrence.

The first paragraph of this Section 3.02 will not prohibit the Incurrence of the following Indebtedness:

(a) Indebtedness of the Company and the Restricted Subsidiaries Incurred pursuant to a Credit Facility in an aggregate principal amount up to the greater of (x) $500 million or (y) 35% of Adjusted Consolidated Net Tangible Assets, in each case, determined as of the date of the Incurrence of the Indebtedness;

(b) Guarantees of Indebtedness of the Company or any Subsidiary Guarantor Incurred in accordance with the provisions of the Indenture; provided that if the Indebtedness that is being Guaranteed is Guaranteed by a Subsidiary Guarantor and is (x) Senior Subordinated Indebtedness or Guarantor Senior Subordinated Indebtedness, then the related Guarantee shall rank equally in right of payment to the Subsidiary Guarantee or (y) a Subordinated Obligation or a Guarantor Subordinated Obligation, then the related Guarantee shall be subordinated in right of payment to the Subsidiary Guarantee;

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(c) Indebtedness of the Company owing to and held by any Restricted Subsidiary or Indebtedness of a Restricted Subsidiary owing to and held by the Company or any Restricted Subsidiary; provided , however , that:

(i) if the Company is the obligor on the Indebtedness, the Indebtedness is subordinated in right of payment to all obligations with respect to the Notes;

(ii) if a Subsidiary Guarantor is the obligor on the Indebtedness and the Company or a Subsidiary Guarantor is not the obligee, such Indebtedness is subordinated in right of payment to the Subsidiary Guarantees of that Subsidiary Guarantor; and

(iii) any subsequent issuance or transfer of Capital Stock, sale or other transfer of any such Indebtedness or other event that results in any such Indebtedness being held by a Person other than the Company or a Restricted Subsidiary of the Company shall be deemed, in each case, to constitute an Incurrence of such Indebtedness by the Company or such Subsidiary, as the case may be, as of the date such Indebtedness first became held by such Person;

(d) Indebtedness represented by (x) the Notes issued on the Issue Date, and the Subsidiary Guarantees, (y) any Indebtedness (other than the Indebtedness described in clauses (a), (b), (c), (f), (h), (i) and (j) of this paragraph) outstanding on the Issue Date, and (z) any Refinancing Indebtedness Incurred in respect of any Indebtedness described in this clause (d) or clause (e) of this paragraph or Incurred pursuant to the first paragraph of this Section 3.02;

(e) Indebtedness of a Person that becomes a Restricted Subsidiary or is acquired by the Company or a Restricted Subsidiary or merged into the Company or a Restricted Subsidiary Incurred and outstanding on the date on which such Person became a Restricted Subsidiary or was acquired by or was merged into the Company or a Restricted Subsidiary (other than Indebtedness Incurred (x) to provide all or any portion of the funds utilized to consummate the transaction or series of related transactions pursuant to which such Person became a Restricted Subsidiary or was otherwise acquired by or merged into the Company or a Restricted Subsidiary or (y) otherwise in connection with, or in contemplation of, such acquisition); provided, however, that, at the time such Person became a Restricted Subsidiary or is acquired by or merged into the Company or a Restricted Subsidiary, the Company would have been able to Incur $1.00 of additional Indebtedness pursuant to the first paragraph of this Section 3.02 after giving effect to the Incurrence of such Indebtedness;

(f) Indebtedness under Currency Agreements, Commodity Agreements and Interest Rate Agreements; provided, that, in the case of Currency Agreements or Commodity Agreements, such Currency Agreements or Commodity Agreements are related to business transactions of the Company or its Restricted Subsidiaries entered into in the ordinary course of business and, in the case of Currency Agreements, Commodity Agreements and Interest Rate Agreements, such Currency Agreements, Commodity Agreements and Interest Rate Agreements are entered into for bona fide hedging purposes of the Company or its Restricted Subsidiaries (as determined in good faith by the senior management of the Company);

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(g) the Incurrence by the Company or any of its Restricted Subsidiaries of Indebtedness represented by Capital Lease Obligations, mortgage financings or purchase money obligations, in each case Incurred for the purpose of financing all or any part of the purchase price or cost of construction or improvements of property used in the business of the Company or the Restricted Subsidiary, in an aggregate principal amount not to exceed the greater of (i) $50 million and (ii) 2.0% of Adjusted Consolidated Net Tangible Assets at any time outstanding and Refinancing Indebtedness Incurred to Refinance any Indebtedness Incurred pursuant to this clause (g);

(h) Indebtedness Incurred in respect of workers’ compensation claims, self-insurance obligations, bid, reimbursement, performance, surety, appeal and similar bonds, asset retirement obligations, completion guarantees provided by the Company or a Restricted Subsidiary in the ordinary course of business, or required by regulatory authorities in connection with the conduct by the Company and its Restricted Subsidiaries of their businesses, including supporting Guarantees and letters of credit (in each case other than for an obligation for money borrowed);

(i) Indebtedness arising from agreements of the Company or a Restricted Subsidiary providing for indemnification, adjustment of purchase price or similar obligations, in each case, Incurred or assumed in connection with the disposition of any business, assets or Capital Stock of the Company or a Restricted Subsidiary;

(j) Indebtedness arising from the honoring by a bank or other financial institution of a check, draft or similar instrument (except in the case of daylight overdrafts) drawn against insufficient funds in the ordinary course of business; provided , however , that such Indebtedness is extinguished within five business days of the Incurrence;

(k) Indebtedness, including Refinancing Indebtedness, Incurred by a Foreign Subsidiary in an aggregate amount not to exceed the greater of $30 million or 15% of such Foreign Subsidiary’s Adjusted Consolidated Net Tangible Assets at any time outstanding;

(l) any Guarantee by the Company or any Restricted Subsidiary that directly owns Capital Stock of an Unrestricted Subsidiary that is recourse only to, and secured only by, such Capital Stock; and

(m) in addition to the items referred to in clauses (a) through (l) of this paragraph, Indebtedness of the Company and its Restricted Subsidiaries in an aggregate outstanding principal amount which, when taken together with the principal amount of all other Indebtedness Incurred pursuant to this clause (m) and then outstanding, will not exceed the greater of $50 million or 3.0% of the Company’s Adjusted Consolidated Net Tangible Assets, in each case, determined as of the date of the Incurrence of the Indebtedness.

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For purposes of determining compliance with, and the outstanding principal amount of any particular Indebtedness Incurred pursuant to and in compliance with, this Section 3.02:

(i) Indebtedness permitted by this Section 3.02 need not be permitted solely by one provision permitting such Indebtedness but may be permitted in part by one such provision and in part by one or more other provisions of this Section 3.02 permitting such Indebtedness;

(ii) in the event that Indebtedness meets the criteria of more than one of the provisions permitting the Incurrence of Indebtedness described in the first and second paragraphs above, the Company, in its sole discretion, may classify (or subsequently reclassify) such item of Indebtedness as being permitted by one or more such provisions;

(iii) all Indebtedness outstanding on the date of the Indenture under the Senior Credit Agreement shall be deemed Incurred under clause (a) of the second paragraph of this Section 3.02 and not the first paragraph or clause (d) of the second paragraph of this Section 3.02;

(iv) Guarantees of, or obligations in respect of letters of credit relating to, Indebtedness which is otherwise included in the determination of a particular amount of Indebtedness shall not be included;

(v) if obligations in respect of letters of credit are Incurred pursuant to a Credit Facility and are being treated as Incurred pursuant to clause (a) of the second paragraph of this Section 3.02 and the letters of credit relate to other Indebtedness, then such other Indebtedness shall not be included;

(vi) no item of Indebtedness will be given effect more than once in any calculation contemplated by this Section 3.02 and no individual item or related items of Indebtedness will be given effect at an aggregate amount in excess of the aggregate amount required to satisfy and discharge the principal amount of such item or related items of Indebtedness;

(vii) the principal amount of any Disqualified Stock of the Company or a Restricted Subsidiary, or Preferred Stock of a Restricted Subsidiary that is not a Subsidiary Guarantor, will be equal to the greater of the maximum mandatory redemption or repurchase price (not including, in either case, any redemption or repurchase premium) or the liquidation preference thereof; and

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(viii) the amount of Indebtedness issued at a price that is less than the principal amount thereof will be equal to the amount of the liability in respect thereof determined in accordance with GAAP.

Accrual of interest, accrual of dividends, the accretion of accreted value, the payment of interest in the form of additional Indebtedness and the payment of dividends in the form of additional shares of Preferred Stock or Disqualified Stock will not be deemed to be an Incurrence of Indebtedness for purposes of this Section 3.02. The amount of any Indebtedness outstanding as of any date shall be (i) the accreted value thereof in the case of any Indebtedness issued with original issue discount and (ii) the principal amount or liquidation preference thereof, together with any interest thereon that is more than 30 days past due, in the case of any other Indebtedness.

In addition, the Company will not permit any of its Unrestricted Subsidiaries to Incur any Indebtedness or issue any shares of Disqualified Stock, other than Non-Recourse Debt. If at any time an Unrestricted Subsidiary becomes a Restricted Subsidiary, any Indebtedness of such Subsidiary shall be deemed to be Incurred by a Restricted Subsidiary as of such date (and, if such Indebtedness is not permitted to be Incurred as of such date under this Section 3.02, the Company shall be in Default of this Section 3.02).

For purposes of determining compliance with any U.S. dollar-denominated restriction on the Incurrence of Indebtedness, the U.S. dollar-equivalent principal amount of Indebtedness denominated in a foreign currency will be calculated based on the relevant currency exchange rate in effect on the date the Indebtedness was Incurred, in the case of term Indebtedness, or first committed, in the case of revolving credit Indebtedness; provided that if such Indebtedness is Incurred to refinance other Indebtedness denominated in a foreign currency, and the refinancing would cause the applicable U.S. dollar-dominated restriction to be exceeded if calculated at the relevant currency exchange rate in effect on the date of the refinancing, such U.S. dollar-dominated restriction shall be deemed not to have been exceeded so long as the principal amount of such refinancing Indebtedness does not exceed the principal amount of such Indebtedness being refinanced. Notwithstanding any other provision of this Section 3.02, the maximum amount of Indebtedness that the Company may Incur pursuant to this Section 3.02 shall not be deemed to be exceeded solely as a result of fluctuations in the exchange rate of currencies. The principal amount of any Indebtedness Incurred to refinance other Indebtedness, if Incurred in a different currency from the Indebtedness being refinanced, will be calculated based on the currency exchange rate applicable to the currencies in which the Refinancing Indebtedness is denominated that is in effect on the date of such refinancing.

Section 3.03 . Limitation on Layering. The Company will not Incur any Indebtedness if such Indebtedness is subordinate in right of payment to any Senior Indebtedness unless the Indebtedness is Senior Subordinated Indebtedness or is contractually subordinated in right of payment to Senior Subordinated

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Indebtedness. No Subsidiary Guarantor will Incur any Indebtedness if the Indebtedness is subordinate in right of payment to any Guarantor Senior Indebtedness of the Subsidiary Guarantor unless the Indebtedness is Guarantor Senior Subordinated Indebtedness of the Subsidiary Guarantor or is contractually subordinated in right of payment to Guarantor Senior Subordinated Indebtedness of the Subsidiary Guarantor.

Section 3.04 . Limitation on Restricted Payments. The Company will not, and will not permit any of its Restricted Subsidiaries, directly or indirectly, to:

(a) pay any dividend or make any distribution on or in respect of its Capital Stock (including any payment in respect of its Capital Stock in connection with any merger or consolidation involving the Company or any of its Restricted Subsidiaries) except:

(i) dividends or distributions payable in Capital Stock of the Company (other than Disqualified Stock) or in options, warrants or other rights to purchase Capital Stock of the Company; and

(ii) dividends or distributions payable to the Company or a Restricted Subsidiary (and if the Restricted Subsidiary is not a Wholly-Owned Subsidiary, to its other holders of Capital Stock on a pro rata basis);

(b) purchase, redeem, retire or otherwise acquire for value any Capital Stock of the Company or any direct or indirect parent of the Company held by Persons other than the Company or a Restricted Subsidiary (other than in exchange for Capital Stock of the Company or any direct or indirect parent of the Company (other than Disqualified Stock));

(c) purchase, repurchase, redeem, defease or otherwise acquire or retire for value, prior to scheduled maturity, scheduled repayment or scheduled sinking fund payment, any Subordinated Obligations or Guarantor Subordinated Obligations (other than (x) the purchase, repurchase, redemption, defeasance or other acquisition or retirement of Subordinated Obligations or Guarantor Subordinated Obligations purchased in anticipation of satisfying a sinking fund obligation, principal installment or final maturity, in each case due within one year of the date of purchase, repurchase, redemption, defeasance or other acquisition or retirement and (y) Indebtedness permitted under clause (c) of the second paragraph under Section 3.02); or

(d) make any Restricted Investment in any Person;

(any such dividend, distribution, purchase, redemption, repurchase, defeasance, other acquisition, retirement or Restricted Investment referred to in clauses (a) through (d) of this paragraph being referred to herein as a “ Restricted Payment ”), if at the time the Company or such Restricted Subsidiary makes such Restricted Payment:

(1) a Default shall have occurred and be continuing (or would result therefrom); or

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(2) the Company is not able to Incur an additional $1.00 of Indebtedness pursuant to the first paragraph under Section 3.02 above after giving effect, on a pro forma basis, to the Restricted Payment; or

(3) the aggregate amount of the Restricted Payment and all other Restricted Payments made subsequent to the Issue Date would exceed the sum of:

(i) 50% of Consolidated Net Income for the period (treated as one accounting period) from the beginning of the most recent fiscal quarter ended prior to the Issue Date to the end of the most recent fiscal quarter ending prior to the date of such Restricted Payment for which financial statements are in existence (or, in case such Consolidated Net Income is a deficit, minus 100% of such deficit);

(ii) 100% of the aggregate Net Cash Proceeds and the fair market value of Additional Assets received by the Company from the issue or sale of its Capital Stock (other than Disqualified Stock) or other capital contributions subsequent to the Issue Date (other than Net Cash Proceeds received from an issuance or sale of such Capital Stock to a Subsidiary of the Company or an employee stock ownership plan, option plan or similar trust to the extent such sale to an employee stock ownership plan, option plan or similar trust is financed by loans from or Guaranteed by the Company or any Restricted Subsidiary unless such loans have been repaid with cash on or prior to the date of determination);

(iii) the amount by which Indebtedness of the Company or its Restricted Subsidiaries is reduced on the Company’s balance sheet upon the conversion or exchange (other than by a Subsidiary of the Company) subsequent to the Issue Date of any Indebtedness of the Company or its Restricted Subsidiaries convertible into or exchangeable for Capital Stock (other than Disqualified Stock) of the Company (less the amount of any cash, or the fair market value of any other property, distributed by the Company upon such conversion or exchange); and

(iv) the amount equal to payments received by the Company or any Restricted Subsidiary in respect of, or the net reduction in, Restricted Investments made by the Company or any of its Restricted Subsidiaries in any Person resulting from:

(A) repurchases or redemptions of such Restricted Investments by the Person in which such Restricted Investments are made, proceeds realized upon the sale of such Restricted Investment to an unaffiliated purchaser or payments in respect of such Restricted Investment, whether through interest payments, principal payments, dividends, distributions or otherwise, by such Person to the Company or any Restricted Subsidiary; or

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(B) the redesignation of Unrestricted Subsidiaries as Restricted Subsidiaries (valued in each case as provided in the definition of “ Investment ”) not to exceed, in the case of any Unrestricted Subsidiary, the amount of Investments previously made by the Company or any Restricted Subsidiary in such Unrestricted Subsidiary;

which amount in each case under clause (iv) was included in the calculation of the amount of Restricted Payments; provided , however , that no amount will be included under clause (iv) to the extent it is already included in Consolidated Net Income.

The provisions of the preceding paragraph will not prohibit:

(a) any purchase, repurchase, redemption, defeasance or other acquisition or retirement of Capital Stock, Disqualified Stock or Subordinated Obligations or Guarantor Subordinated Obligations made by exchange for, or out of the proceeds of the substantially concurrent sale of, Capital Stock of the Company (other than Disqualified Stock and other than Capital Stock issued or sold to a Subsidiary or an employee stock ownership plan or similar trust to the extent such sale to an employee stock ownership plan or similar trust is financed by loans from or Guaranteed by the Company or any Restricted Subsidiary unless such loans have been repaid with cash on or prior to the date of determination); provided , however , that (x) such purchase, repurchase, redemption, defeasance, acquisition or retirement will be excluded in subsequent calculations of the amount of Restricted Payments and (y) the Net Cash Proceeds from such sale of Capital Stock will be excluded from clause (c)(ii) of the preceding paragraph;

(b) any purchase, repurchase, redemption, defeasance or other acquisition or retirement of Subordinated Obligations or Guarantor Subordinated Obligations made by exchange for, or out of the proceeds of the substantially concurrent sale of, Subordinated Obligations or any purchase, repurchase, redemption, defeasance or other acquisition or retirement of Guarantor Subordinated Obligations made by exchange for or out of the proceeds of the substantially concurrent sale of Guarantor Subordinated Obligations that, in each case, is permitted to be Incurred under Section 3.02 of this First Supplemental Indenture and that in each case constitutes Refinancing Indebtedness; provided , however , that such purchase, repurchase, redemption, defeasance, acquisition or retirement will be excluded in subsequent calculations of the amount of Restricted Payments;

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(c) any purchase, repurchase, redemption, defeasance or other acquisition or retirement of Disqualified Stock of the Company or a Restricted Subsidiary made by exchange for or out of the proceeds of the substantially concurrent sale of Disqualified Stock of the Company or such Restricted Subsidiary, as the case may be, that, in each case, is permitted to be Incurred under Section 3.02 of this First Supplemental Indenture and that in each case constitutes Refinancing Indebtedness; provided , however , that such purchase, repurchase, redemption, defeasance, acquisition or retirement will be excluded in subsequent calculations of the amount of Restricted Payments;

(d) so long as no Default or Event of Default has occurred and is continuing, any purchase or redemption of Subordinated Obligations or Guarantor Subordinated Obligations from Net Available Cash to the extent permitted under Section 3.07 of this First Supplemental Indenture; provided , however , that such purchase or redemption will be excluded in subsequent calculations of the amount of Restricted Payments;

(e) dividends paid within 60 days after the date of declaration if at such date of declaration the dividend would have complied with this provision; provided , however , that such dividends will be included in subsequent calculations of the amount of Restricted Payments;

(f) so long as no Default or Event of Default has occurred and is continuing,

(i) the purchase, redemption or other acquisition, cancellation or retirement for value of Capital Stock, or options, warrants, equity appreciation rights or other rights to purchase or acquire Capital Stock of the Company or any Restricted Subsidiary or any direct or indirect parent of the Company held by any existing or former employees or directors of the Company or any Subsidiary of the Company or their assigns, estates or heirs, in each case in accordance with the terms of employee stock option or stock purchase agreements or other agreements to compensate employees or directors; provided that such purchases, redemptions acquisitions, cancellations or retirements pursuant to this clause will not exceed $2.0 million in the aggregate during any calendar year (with unused amounts carried over into the following year); provided further however, that the amount of any such purchases, redemptions, acquisitions, cancellations or retirements will be included in subsequent calculations of the amount of Restricted Payments; and

(ii) loans or advances to employees or directors of the Company or any Subsidiary of the Company the proceeds of which are used to purchase Capital Stock of the Company, in an aggregate amount not in excess of $2.0 million at any one time outstanding; provided , however , that the amount of such loans and advances will be included in subsequent calculations of the amount of Restricted Payments;

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(g) so long as no Default or Event of Default has occurred and is continuing, the declaration and payment of dividends to holders of any class or series of Disqualified Stock of the Company issued in accordance with the terms of the Indenture to the extent such dividends are included in the definition of “ Consolidated Interest Expense ;” provided , however , that the payment of such dividends will be excluded in subsequent calculations of the amount of Restricted Payments;

(h) repurchases of Capital Stock deemed to occur upon the exercise of stock options, warrants or other convertible securities if such Capital Stock represents a portion of the exercise price thereof; provided , however , that such repurchases will be excluded from subsequent calculations of the amount of Restricted Payments;

(i) the purchase, repurchase, redemption, defeasance or other acquisition or retirement for value of any Subordinated Obligation (i) at a purchase price not greater than 101% of the principal amount of such Subordinated Obligation in the event of a Change of Control in accordance with provisions similar to Section 3.14 of this First Supplemental Indenture or (ii) at a purchase price not greater than 100% of the principal amount thereof in accordance with provisions similar to Section 3.07 of this First Supplemental Indenture; provided that, prior to or simultaneously with such purchase, repurchase, redemption, defeasance or other acquisition or retirement, the Company has made the Change of Control Offer or Asset Disposition Offer, as applicable, as required with respect to the Notes and has completed the repurchase or redemption of all Notes validly tendered for payment in connection with such Change of Control Offer or Asset Disposition Offer; provided , however , that such repurchases will be excluded from subsequent calculations of the amount of Restricted Payments;

(j) any redemption of share purchase rights at a redemption price not to exceed $0.01 per right; provided , however , that such redemption will be included in subsequent calculations of the amount of Restricted Payments;

(k) the payment of cash in lieu of fractional shares of Capital Stock in connection with any transaction otherwise permitted under the Indenture; provided , however , that such payment will be included in subsequent calculations of the amount of Restricted Payments;

(l) payments to dissenting stockholders not to exceed $5 million (x) pursuant to applicable law or (y) in connection with the settlement or other satisfaction of legal claims made pursuant to or in connection with a consolidation, merger or transfer of assets in connection with a transaction that is not prohibited by the Indenture; provided , however , that such payments will be included in subsequent calculations of the amount of Restricted Payments;

(m) Restricted Payments in an amount not to exceed $40 million; provided , however , that the amount of the Restricted Payments will be included in subsequent calculations of the amount of Restricted Payments; and

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(n) so long as (i) no Default or Event of Default has occurred and is continuing and (ii) immediately after giving effect to such dividend or distribution on a pro forma basis, the Company’s Consolidated Leverage Ratio would be less than 1.50:1, the declaration and payment of a Permitted Distribution; provided, however, that the amount of the Permitted Distribution will not be included in subsequent calculations of the amount of Restricted Payments.

The amount of all Restricted Payments (other than cash) shall be the fair market value on the date of the Restricted Payment of the asset(s) or securities proposed to be paid, transferred or issued by the Company or such Restricted Subsidiary, as the case may be, pursuant to the Restricted Payment. The fair market value of any cash Restricted Payment shall be its face amount and any non-cash Restricted Payment shall be determined conclusively by the Board of Directors of the Company acting in good faith, such determination to be based upon an opinion or appraisal issued by an accounting, appraisal or investment banking firm of national standing if such fair market value is estimated in good faith by the Board of Directors of the Company to exceed $25 million.

Section 3.05 . Limitation on Liens. The Company may not, and may not permit any of its Restricted Subsidiaries to, directly or indirectly, create, Incur or suffer to exist any Lien (the “Initial Lien”) (other than Permitted Liens) upon any of its property or assets (including Capital Stock of Restricted Subsidiaries), whether owned on the Issue Date or acquired after that date, which Lien secures any Senior Subordinated Indebtedness, or Subordinated Obligations, Guarantor Senior Subordinated Indebtedness or Guarantor Subordinated Obligations, unless contemporaneously with the Incurrence of such Lien effective provision is made to secure the Indebtedness due with respect to the Notes or, with respect to Liens on any Restricted Subsidiary’s property or assets, any Subsidiary Guarantee of such Restricted Subsidiary, equally and ratably with (or prior to in the case of Liens with respect to Subordinated Obligations or Guarantor Subordinated Obligations, as the case may be) the Indebtedness secured by such Lien for so long as such Indebtedness is so secured.

Any Lien created for the benefit of the holders of the Notes pursuant to the preceding paragraph shall provide by its terms that such Lien shall be automatically and unconditionally released and discharged upon the release and discharge of the Initial Lien.

Section 3.06 . Limitation on Restrictions on Distributions from Restricted Subsidiaries. The Company may not, and may not permit any Restricted Subsidiary to, create or otherwise cause or permit to exist or become effective any consensual encumbrance or consensual restriction on the ability of any Restricted Subsidiary to:

(a) pay dividends or make any other distributions on its Capital Stock or pay any Indebtedness or other obligations owed to the Company or any Restricted Subsidiary (the priority of any Preferred Stock in receiving dividends or

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liquidating distributions prior to dividends or liquidating distributions being paid on Common Stock and any subordination of any such Indebtedness or other obligations being deemed not to constitute such encumbrances or restrictions);

(b) make any loans or advances to the Company or any Restricted Subsidiary (the subordination of loans or advances made to the Company or any Restricted Subsidiary to other Indebtedness Incurred by the Company or any Restricted Subsidiary being deemed not to constitute such an encumbrance or restriction); or

(c) transfer any of its property or assets to the Company or any Restricted Subsidiary.

The preceding provisions will not prohibit:

(i) any encumbrance or restriction pursuant to an agreement in effect at or entered into on the Issue Date, including, without limitation, the Indenture, the Notes and the Senior Credit Agreement in effect on such date;

(ii) any encumbrance or restriction with respect to a Restricted Subsidiary pursuant to an agreement relating to any Capital Stock or Indebtedness Incurred by a Restricted Subsidiary on or before the date on which the Restricted Subsidiary was acquired by the Company (other than Capital Stock or Indebtedness Incurred as consideration in, or to provide all or any portion of the funds utilized to consummate, the transaction or series of related transactions pursuant to which such Restricted Subsidiary became a Restricted Subsidiary or was acquired by the Company or in contemplation of the transaction or transactions) and outstanding on such date provided, that any such encumbrance or restriction shall not extend to any assets or property of the Company or any other Restricted Subsidiary other than the assets and property so acquired;

(iii) any encumbrance or restriction with respect to a Restricted Subsidiary pursuant to an agreement effecting a refunding, replacement or refinancing of Indebtedness Incurred pursuant to an agreement referred to in clause (i) or (ii) of this paragraph or this clause (iii) or contained in any amendment, restatement, modification, renewal, supplemental, refunding, replacement or refinancing of an agreement referred to in clause (i) or (ii) of this paragraph or this clause (iii), including successive refundings, replacements or refinancings; provided , however , that the encumbrances and restrictions with respect to such Restricted Subsidiary contained in any such agreement taken as a whole are no less favorable in any material respect to the Holders of the Notes than the encumbrances and restrictions contained in such agreements referred to in clauses (i) or (ii) of this paragraph on the Issue Date or the date such Restricted Subsidiary became a Restricted Subsidiary or was merged into a Restricted Subsidiary, whichever is applicable;

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(iv) in the case of clause (c) of the first paragraph of this Section 3.06, any encumbrance or restriction:

(1) that restricts in a customary manner the subletting, assignment or transfer of any property or asset that is subject to a lease, license or similar contract, or the assignment or transfer of any such lease, license or other contract;

(2) contained in mortgages, pledges or other security agreements permitted under the Indenture securing Indebtedness of the Company or a Restricted Subsidiary to the extent such encumbrances or restrictions restrict the transfer of the property subject to such mortgages, pledges or other security agreements; or

(3) pursuant to customary provisions restricting dispositions of real property interests set forth in any reciprocal easement agreements of the Company or any Restricted Subsidiary;

(v)(i) purchase money obligations for property acquired in the ordinary course of business and (ii) Capital Lease Obligations permitted under the Indenture, in each case, that impose encumbrances or restrictions of the nature described in clause (c) of the first paragraph of this Section 3.06 on the property so acquired;

(vi) any restriction with respect to a Restricted Subsidiary (or any of its property or assets) imposed pursuant to an agreement entered into for the direct or indirect sale or disposition of all or substantially all the Capital Stock or assets of such Restricted Subsidiary (or the property or assets that are subject to such restriction) pending the closing of such sale or disposition;

(vii) customary encumbrances or restrictions imposed pursuant to any agreement referred to in the definition of “ Permitted Business Investment ;”

(viii) net worth provisions in leases and other agreements entered into by the Company or any Restricted Subsidiary in the ordinary course of business;

(ix) encumbrances or restrictions arising or existing by reason of applicable law or any applicable rule, regulation or order;

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(x) encumbrances and restrictions contained in contracts entered into the ordinary course of business, not relating to any Indebtedness, and that do not individually or in the aggregate, detract from the value of, or from the ability of the Company and the Restricted Subsidiaries to realized the value of, property or assets of the Company or any Restricted Subsidiary in any manner material to the Company or any Restricted Subsidiary;

(xi) with respect to any Foreign Subsidiary, any encumbrance or restriction contained in the terms of any Indebtedness or any agreement pursuant to which such Indebtedness was Incurred if:

(a) either (1) the encumbrance or restriction applies only in the event of a payment default or a default with respect to a financial covenant in such Indebtedness or agreement or (2) the Company determines that any such encumbrance or restriction will not materially affect the Company’s ability to make principal or interest payments on the Notes, as determined in good faith by the Board of Directors of the Company, whose determination shall be conclusive, and

(b) the encumbrance or restriction is not materially more disadvantageous to the holders of the Notes than is customary in comparable financing (as determined by the Company):

(xii) restrictions on cash or other deposits imposed by customers under contracts entered into in the ordinary course or business; or

(xiii) provisions with respect to the disposition or distribution of assets or property in operating agreements, joint venture agreements, development agreements, area of mutual interest agreements and other agreements that are customary in the Oil and Gas Business and entered into in the ordinary course of business.

Section 3.07 . Limitation on Sales of Assets and Subsidiary Stock. The Company may not, and may not permit any of its Restricted Subsidiaries to, make any Asset Disposition unless:

(a) the Company or the Restricted Subsidiary, as the case may be, receives consideration at the time of the Asset Disposition at least equal to the fair market value of the assets subject to the Asset Disposition (determined on the date of contractually agreeing to such Asset Disposition), as determined in good faith by senior management of the Company or, if the consideration with respect to such Asset Disposition exceeds $75 million, the Board of Directors of the Company (including as to the value of all non-cash consideration); and

(b) at least 75% of the consideration from the Asset Disposition received by the Company or the Restricted Subsidiary, as the case may be, is in the form of cash or Cash Equivalents or Additional Assets or any combination thereof;

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The Company or such Restricted Subsidiary, as the case may be, may elect to apply all or any portion of the Net Available Cash from such Asset Disposition either:

(a) to prepay, repay, purchase, repurchase, redeem, defease or otherwise acquire or retire Senior Indebtedness of the Company (other than Disqualified Stock or Subordinated Obligations) or Indebtedness of a Restricted Subsidiary (other than any Disqualified Stock or Guarantor Senior Subordinated Indebtedness or Guarantor Subordinated Obligation of a Wholly-Owned Subsidiary Guarantor) (in each case other than Indebtedness owed to the Company or an Affiliate of the Company) within 365 days from the later of the date of such Asset Disposition or the receipt of such Net Available Cash; provided , however , that, in connection with any prepayment, repayment, purchase, repurchase, redemption, defeasance, or acquisition of Indebtedness pursuant to this clause (a), the Company or such Restricted Subsidiary will retire such Indebtedness and, in the case of revolving Indebtedness, will cause the related commitment (if any) to be permanently reduced in an amount equal to the principal amount so retired; or

(b) to invest in Additional Assets or make Permitted Business Investments within 365 days from the later of the date of such Asset Disposition or the receipt of such Net Available Cash;

provided , that, pending the final application of any such Net Available Cash in accordance with clauses (a) or (b) above, the Company and its Restricted Subsidiaries may temporarily reduce Indebtedness or otherwise invest such Net Available Cash in any manner not prohibited by the Indenture.

Any Net Available Cash from Asset Dispositions that is not applied or invested as provided in the preceding paragraph will be deemed to constitute “ Excess Proceeds .” Not later than the 366th day after an Asset Disposition, if the aggregate amount of Excess Proceeds exceeds $25 million, the Company must make an offer (“ Asset Disposition Offer ”) to all Holders of Notes and to the extent required by the terms of other Senior Subordinated Indebtedness, to all holders of other Senior Subordinated Indebtedness outstanding with similar provisions requiring the Company to make an offer to purchase such Senior Subordinated Indebtedness with the proceeds from any Asset Disposition (“ Pari Passu Notes ”), to purchase the maximum principal amount of Notes and any Pari Passu Notes to which the Asset Disposition Offer applies that may be purchased out of the Excess Proceeds, at an offer price in cash in an amount equal to 100% of the principal amount of the Notes and Pari Passu Notes plus accrued and unpaid interest to the date of purchase, in accordance with the procedures set forth in the Indenture or the agreements governing the Pari Passu Notes, as applicable, in each case in a minimum principal amount of $2,000 and integral multiples of

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$1,000 in excess thereof. To the extent that the aggregate amount of Notes and Pari Passu Notes so validly tendered and not properly withdrawn pursuant to an Asset Disposition Offer is less than the Excess Proceeds, the Company may use any remaining Excess Proceeds for general corporate purposes, subject to the other covenants contained in the Indenture. If the aggregate principal amount of Notes surrendered by Holders thereof and other Pari Passu Notes surrendered by holders or lenders, collectively, exceeds the amount of Excess Proceeds, the Trustee shall select the Notes and Pari Passu Notes to be purchased pro rata on the basis of the aggregate principal amount of tendered Notes and Pari Passu Notes. Upon completion of the Asset Disposition Offer, the amount of Excess Proceeds will be reset at zero.

The Asset Disposition Offer must remain open for a period of 20 business days following its commencement, except to the extent that a longer period is required by applicable law (the “ Asset Disposition Offer Period ”). No later than five Business Days after the termination of the Asset Disposition Offer Period (the “ Asset Disposition Purchase Date ”), the Company will purchase the principal amount of Notes and Pari Passu Notes required to be purchased pursuant to the Asset Disposition Offer (the “ Asset Disposition Offer Amount ”) or, if less than the Asset Disposition Offer Amount has been so validly tendered, all Notes and Pari Passu Notes validly tendered in response to the Asset Disposition Offer.

If the Asset Disposition Purchase Date is on or after a Regular Record Date and on or before the related Interest Payment Date, any accrued and unpaid interest will be paid to the Person in whose name a Note is registered at the close of business on such Record Date, and no additional interest will be payable to Holders who tender Notes pursuant to the Asset Disposition Offer.

On or before the Asset Disposition Purchase Date, the Company must, to the extent lawful, accept for payment, on a pro rata basis to the extent necessary, the Asset Disposition Offer Amount of Notes and Pari Passu Notes or portions of Notes and Pari Passu Notes so validly tendered and not properly withdrawn pursuant to the Asset Disposition Offer, or if less than the Asset Disposition Offer Amount has been validly tendered and not properly withdrawn, all Notes and Pari Passu Notes so validly tendered and not properly withdrawn, in each case in a minimum principal amount of $2,000 and integral multiples of $1,000 in excess thereof. The Company or the Paying Agent, as the case may be, must promptly (but in any case not later than five business days after the termination of the Asset Disposition Offer Period) mail or deliver to each tendering Holder of Notes or holder or lender of Pari Passu Notes, as the case may be, an amount equal to the purchase price of the Notes or Pari Passu Notes so validly tendered and not properly withdrawn by such holder or lender, as the case may be, and accepted by the Company for purchase, and the Company must promptly issue a new Note, and the Trustee, upon delivery of an Officers’ Certificate from the Company, must authenticate and mail or deliver such new Note to such Holder, in a principal amount equal to any unpurchased portion of the Note surrendered; provided that each such new Note will be in a minimum principal amount of $2,000 or an

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integral multiple of $1,000 in excess thereof. In addition, the Company must take any and all other actions required by the agreements governing the Pari Passu Notes. Any Note not so accepted must be promptly mailed or delivered by the Company to the Holder thereof. The Company will publicly announce the results of the Asset Disposition Offer on the Asset Disposition Purchase Date.

For the purposes of this Section 3.07, the following will be deemed to be cash:

(a) the assumption by the transferee of Indebtedness (other than Senior Subordinated Indebtedness, Subordinated Obligations or Disqualified Stock) of the Company or Indebtedness of a Restricted Subsidiary (other than Guarantor Senior Subordinated Indebtedness, Guarantor Subordinated Obligations or Disqualified Stock of any Restricted Subsidiary that is a Subsidiary Guarantor) and the release of the Company or the Restricted Subsidiary from all liability on such Indebtedness in connection with the Asset Disposition; and

(b) securities, notes or other obligations received by the Company or any Restricted Subsidiary from the transferee that are converted by the Company or such Restricted Subsidiary into cash within 90 days after consummation of the receipt thereof.

The Company may not, and may not permit any Restricted Subsidiary to, engage in any Asset Swaps, unless:

(a) at the time of entering into the Asset Swap and immediately after giving effect to the Asset Swap, no Default or Event of Default shall have occurred and be continuing or would occur as a consequence thereof; and

(b) in the event the Asset Swap involves the transfer by the Company or any Restricted Subsidiary of assets having an aggregate fair market value, as determined by the Board of Directors of the Company in good faith, in excess of $25 million, the terms of the Asset Swap have been approved by a majority of the members of the Board of Directors of the Company.

The Company will comply, to the extent applicable, with the requirements of Section 14(e) of the Exchange Act and any other securities laws or regulations in connection with the repurchase of Notes pursuant to the Indenture. To the extent that the provisions of any securities laws or regulations conflict with provisions of this Section 3.07, the Company will comply with the applicable securities laws and regulations and will be deemed not to have breached its obligations under the Indenture by virtue of such compliance.

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Section 3.08 . Limitation on Affiliate Transactions. The Company may not, and may not permit any of its Restricted Subsidiaries to, directly or indirectly, enter into or conduct any transaction (including the purchase, sale, lease or exchange of any property or the rendering of any service) with any Affiliate of the Company (an “ Affiliate Transaction ”) unless:

(a) the terms of the Affiliate Transaction are not materially less favorable to the Company or the Restricted Subsidiary, as the case may be, than those that might reasonably have been obtained in a comparable transaction at the time of such transaction on an arm’s-length basis from a Person that is not an Affiliate of the Company;

(b) in the event the Affiliate Transaction involves an aggregate consideration in excess of $10 million, but not greater than $50 million, the Company delivers to the Trustee an Officers’ Certificate certifying that such Affiliate Transaction satisfies the criteria in clause (a) above; and

(c) in the event the Affiliate Transaction involves an aggregate consideration in excess of $50 million, the Company delivers to the Trustee an Officers’ Certificate certifying that such Affiliate Transaction satisfies the criteria in clause (a) above and that the terms of such transaction have been approved by a majority of the members of the Board of Directors of the Company having no personal pecuniary interest in such transaction.

The preceding paragraph will not apply to:

(a) any Restricted Payment or Permitted Investment permitted to be made pursuant to Section 3.04 of this First Supplemental Indenture;

(b) any issuance of securities, or other payments, awards or grants in cash, securities or otherwise pursuant to, or the funding of, employment agreements and other compensation arrangements, options to purchase Capital Stock of the Company, restricted stock plans, long-term incentive plans, stock appreciation rights plans, participation plans or similar employee plans and/or insurance and indemnification arrangements provided to or for the benefit of employees and directors approved by the Board of Directors of the Company;

(c) loans or advances to employees, officers or directors in the ordinary course of business of the Company or any of its Restricted Subsidiaries, but in any event not to exceed $2.0 million in the aggregate outstanding at any one time with respect to all loans or advances made since the Issue Date;

(d) any transaction between the Company and a Restricted Subsidiary or between Restricted Subsidiaries and Guarantees issued by the Company or a Restricted Subsidiary for the benefit of the Company or a Restricted Subsidiary, as the case may be, in accordance with Section 3.02 of this First Supplemental Indenture;

(e) any transaction with a joint venture or other entity other than an Unrestricted Subsidiary which would constitute an Affiliate Transaction solely because the Company or a Restricted Subsidiary owns, directly or indirectly, an equity interest in or otherwise controls such joint venture or other entity;

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(f) the issuance or sale of any Capital Stock (other than Disqualified Stock) of the Company or the receipt by the Company of any capital contribution from its shareholders;

(g) indemnities of officers, directors and employees of the Company or any of its Restricted Subsidiaries permitted by charter documents or statutory provisions and any employment agreement or other employee compensation plan or arrangement entered into in the ordinary course of business by the Company or any of its Restricted Subsidiaries;

(h) the payment of reasonable compensation and fees paid to, and indemnity provided on behalf of, officers or directors of the Company or any Restricted Subsidiary;

(i) the performance of obligations of the Company or any of its Restricted Subsidiaries under the terms of any agreement to which the Company or any of its Restricted Subsidiaries is a party as of or on the Issue Date, as these agreements may be amended, modified, supplemented, extended or renewed from time to time; provided , however , that any future amendment, modification, supplement, extension or renewal entered into after the Issue Date will be so excluded only if its terms are not materially less favorable to the Company or the Restricted Subsidiary, as the case may be, than those that might reasonably have been obtained in a comparable transaction at the time of such transaction on an arm’s-length basis from a Person that is not an Affiliate of the Company; and

(j) transactions with customers, clients, suppliers, or purchasers or sellers of goods or services, in each case in the ordinary course of business and otherwise in compliance with the terms of this Indenture which are fair to the Company and its Restricted Subsidiaries, in the reasonable determination of the Board of Directors of the Company or the senior management thereof, or are on terms at least as favorable as might reasonably have been obtained at such time from an unaffiliated party.

Section 3.09 . SEC Reports. Notwithstanding that the Company may not be subject to the reporting requirements of Section 13 or 15(d) of the Exchange Act, the Company will file with the SEC (to the extent the SEC will accept such filing), and make available to the Trustee and the registered Holders of the Notes, the annual reports and the information, documents and other reports (or copies of such portions of any of the foregoing as the SEC may by rules and regulations prescribe) that are specified in Sections 13 and 15(d) of the Exchange Act. If the SEC will not accept such filings, the Company will nevertheless make available such Exchange Act information to the Trustee and the Holders of the Notes as if the Company were subject to the reporting requirements of Section 13 or 15(d) of the Exchange Act.

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Section 3.10 . Merger and Consolidation. Section 10.01 of the Original Indenture shall not apply to the Notes. The provisions set forth in this Section 3.10 shall, with respect to the Notes, supersede in their entirety Section 10.01 of the Original Indenture, and all references in the Original Indenture to Section 10.01 thereof shall, with respect to the Notes, be deemed to be references to this Section 3.10. The Company may not consolidate with or merge with or into any other Person, or transfer all or substantially all its properties and assets to another Person, unless:

(a) the Company is the continuing or surviving Person in the consolidation or merger; or

(b) the Person (if other than the Company) formed by the consolidation or into which the Company is merged or to which all or substantially all of the Company’s properties and assets are transferred is a corporation, partnership, limited liability company, business trust, trust or other legal entity organized and validly existing under the laws of the United States, any state thereof, or the District of Columbia, and expressly assumes, by a supplemental indenture, all of the Company’s obligations under the Notes and the Indenture; and

(c) immediately after the transaction and the Incurrence or anticipated Incurrence of any Indebtedness to be Incurred in connection therewith, no Event of Default exists; and

(d) immediately after giving effect to such transaction, the continuing or surviving Person would be able to Incur at least an additional $1.00 of Indebtedness pursuant to the first paragraph of Section 3.02 of this First Supplemental Indenture; and

(e) each Subsidiary Guarantor shall have by supplemental indenture confirmed that its Subsidiary Guarantee shall apply to such Person’s obligations (if other than the Company) in respect of the Indenture and the Notes shall continue to be in effect;

(f) an Officer’s Certificate is delivered to the Trustee to the effect that the conditions set forth above have been satisfied and an Opinion of Counsel has been delivered to the Trustee to the effect that the conditions set forth above have been satisfied.

For purposes of the first paragraph of this Section 3.10, the sale, lease, conveyance, assignment, transfer, or other disposition of all or substantially all of the properties and assets of one or more Subsidiaries of the Company, which properties and assets, if held by the Company instead of its Subsidiaries, would constitute all or substantially all of the properties and assets of the Company on a consolidated basis, shall be deemed to be the transfer of all or substantially all of the properties and assets of the Company.

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The continuing, surviving or successor Person will succeed to and be substituted for the Company with the same effect as if it had been named in the Indenture as a party thereof, and thereafter the predecessor Person will be relieved of all obligations and covenants under the Indenture and the Notes.

Notwithstanding clauses (c) and (d) above and clause (i)(B) below, (x) any Restricted Subsidiary may consolidate with, merge into or transfer all or part of its properties and assets to the Company or another Restricted Subsidiary and (y) the Company may merge with an Affiliate incorporated solely for the purpose of reincorporating the Company in another jurisdiction; provided that, in the case of a Restricted Subsidiary that merges into the Company, the Company will not be required to comply with clause (e) above.

The Company may not permit any Subsidiary Guarantor to consolidate with or merge with or into any Person (other than another Subsidiary Guarantor) and may not permit the conveyance, transfer or lease of substantially all of the assets of any Subsidiary Guarantor (other than another Subsidiary Guarantor) unless:

(i)(A) the Person formed by the consolidation or into which the Subsidiary Guarantor merged or to which all, or substantially all of the Subsidiary Guarantor’s properties and assets are transferred is a corporation, partnership, limited liability company, business trust, trust or other legal entity organized and validly existing under the laws of the United States, any state thereof, or the District of Columbia and such Person (if not such Subsidiary Guarantor) will expressly assume, by supplemental indenture, all the obligations of such Subsidiary Guarantor under its Subsidiary Guarantee; (B) immediately after the transaction and the Incurrence or anticipated Incurrence of any Indebtedness to be Incurred in connection therewith, no Event of Default exists; and (C) the Company will deliver to the Trustee an Officers’ Certificate and an Opinion of Counsel, each to the effect that the conditions set forth above have been satisfied; and

(ii) the transaction is made in compliance with Section 3.07 of this First Supplemental Indenture.

Section 3.11 . Future Subsidiary Guarantors. The Company will cause each Restricted Subsidiary (other than a Foreign Subsidiary) created or acquired by the Company or one or more of its Restricted Subsidiaries after the Issue Date to execute and deliver to the Trustee a Subsidiary Guarantee pursuant to which such Subsidiary Guarantor will unconditionally Guarantee, on a joint and several basis, the full and prompt payment of the principal of, premium, if any and interest on the Notes on a senior subordinated basis.

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Section 3.12 . Limitation on Lines of Business. The Company may not, and may not permit any Restricted Subsidiary to, engage in any business other than the Oil and Gas Business, except to such extent as would not be material to the Company and its Restricted Subsidiaries taken as a whole.

Section 3.13 . Payments for Consent. Neither the Company nor any of its Restricted Subsidiaries will, directly or indirectly, pay or cause to be paid any consideration, whether by way of interest, fees or otherwise, to any Holder of any Notes for or as an inducement to any consent, waiver or amendment of any of the terms or provisions of the Indenture or the Notes unless such consideration is offered to be paid or is paid to all Holders of the Notes that consent, waive or agree to amend in the time frame set forth in the solicitation documents relating to such consent, waiver or amendment.

Section 3.14 . Offer to Repurchase Upon Change of Control.

(a) If a Change of Control occurs, unless the Company has exercised its right to redeem all of the Notes as described under Section 1.08 of this First Supplemental Indenture, the Company will be required to offer to repurchase from each Holder all or any part (equal to $2,000 or an integral multiple of $1,000 in excess thereof) of such Holder’s Notes at a purchase price in cash equal to 101% of the principal amount of the Notes plus accrued and unpaid interest, if any, to the date of purchase (subject to the right of Holders of record on the relevant Regular Record Date to receive interest due on the relevant Interest Payment Date).

(b) Within 30 days following any Change of Control, unless the Company has exercised its right to redeem the Notes as described under Section 1.08 of this First Supplemental Indenture, the Company will mail a notice (the “ Change of Control Offer ”) to each Holder, with a copy to the Trustee, stating:

(i) that a Change of Control has occurred and that the Company is offering to purchase the Holder’s Notes at a purchase price in cash equal to 101% of the principal amount of the Notes plus accrued and unpaid interest, if any, to the date of purchase (subject to the right of holders of record on a Regular Record Date to receive interest on the relevant Interest Payment Date) (the “ Change of Control Payment ”);

(ii) the repurchase date (which shall be no earlier than 30 days nor later than 60 days from the date such notice is mailed) (the “ Change of Control Payment Date ”); and

(iii) the procedures determined by the Company, consistent with the Indenture, that a Holder must follow in order to have its Notes repurchased.

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(c) On the Change of Control Payment Date, the Company will, to the extent lawful:

(i) accept for payment all Notes or portions of Notes (in a minimum principal amount of $2,000 and integral multiples of $1,000 in excess thereof) properly tendered pursuant to the Change of Control Offer;

(ii) deposit with the Paying Agent for the Notes an amount equal to the Change of Control Payment in respect of all Notes or portions of Notes so tendered; and

(iii) deliver or cause to be delivered to the Trustee the Notes so accepted together with an Officers’ Certificate stating the aggregate principal amount of Notes or portions of Notes being purchased by the Company.

(d) The Paying Agent will promptly mail to each Holder of Notes so tendered the Change of Control Payment for the Notes, and the Trustee will promptly authenticate and mail (or cause to be transferred by book entry) to each Holder a new Note equal in principal amount to any unpurchased portion of the Notes surrendered, if any; provided that each new Note will be in a principal amount of $2,000 or an integral multiple of $1,000 in excess thereof.

(e) If the Change of Control Payment Date is on or after a Regular Record Date and on or before the related Interest Payment Date, any accrued and unpaid interest will be paid to the Person in whose name a Note is registered at the close of business on the Regular Record Date, and no additional interest will be payable to Holders who tender pursuant to the Change of Control Offer.

(f) The Company will not be required to make a Change of Control Offer upon a Change of Control if a third party makes the Change of Control Offer in the manner, at the times and otherwise in compliance with the requirements set forth in the Indenture applicable to a Change of Control Offer made by the Company and purchases all Notes validly tendered and not withdrawn under the Change of Control Offer.

(g) A Change of Control Offer may be made in advance of a Change of Control, conditional upon such Change of Control, if a definitive agreement is in place for the Change of Control at the time of the making of the Change of Control Offer.

(h) The Company will comply, to the extent applicable, with the requirements of Section 14(e) of the Exchange Act and any other securities laws or regulations in connection with the repurchase of Notes pursuant to this Section 3.14. To the extent that the provisions of any securities laws or regulations conflict with provisions of the Indenture, the Company will comply with the applicable securities laws and regulations and will be deemed not to have breached its obligations described in the Indenture by virtue of such compliance.

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ARTICLE 4

E VENTS OF D EFAULT WITH R ESPECT TO THE N OTES

The term “ Event of Default ,” whenever used in the Original Indenture or this First Supplemental Indenture with respect to the Notes, means any one of the following events:

(a) failure to pay principal of or premium, if any, on any Note when due at its Stated Maturity;

(b) failure to pay any interest on any Note when due, which failure continues for 30 calendar days;

(c) failure by the Company or any Subsidiary Guarantor to comply with its obligations under Section 3.10 of this First Supplemental Indenture;

(d) failure by the Company to comply with any of its obligations under Article 3 of this First Supplemental Indenture (other than a failure to purchase Notes which will constitute an Event of Default under clause (e) below and other than a failure to comply with Section 3.10 of this First Supplemental Indenture which is covered by clause (c) above), which failure or breach continues for 30 calendar days after written notice thereof has been given to the Company as provided in the Indenture;

(e) failure to redeem or repurchase any Note when required to do so under the terms thereof;

(f) failure to perform, or breach of, any other covenant of the Company in the Indenture (other than a covenant included in the Indenture solely for the benefit of a series of debt securities other than the Notes), which failure or breach continues for 60 calendar days after there has been given, by registered or certified mail, to the Company by the Trustee or to the Company and the Trustee by the Holders of at least 25% in principal amount of the Outstanding Notes a written notice specifying such default or breach and requiring it to be remedied and stating that such notice is a “ Notice of Default ” under the Indenture;

(g) any nonpayment at maturity or other default (beyond any applicable grace period) under any agreement or instrument relating to any other Indebtedness of the Company or a Significant Subsidiary, the unpaid principal amount of which is not less than $25 million, which default results in the acceleration of the maturity of the Indebtedness prior to its stated maturity or occurs at the final maturity thereof;

(h) Events of Default of the type and subject to the conditions set forth in clauses (g) and (h) of Section 6.01 of the Original Indenture;

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(i) failure by the Company or any Significant Subsidiary or group of Restricted Subsidiaries that, taken together (as of the latest audited consolidated financial statements for the Company and its Restricted Subsidiaries), would constitute a Significant Subsidiary to pay final judgments aggregating in excess of $25 million (net of any amounts that a reputable and creditworthy insurance company has acknowledged liability for in writing), which judgments are not paid, discharged or stayed for a period of 60 calendar days; or

(j) any Subsidiary Guarantee of a Significant Subsidiary or group of Subsidiary Guarantors that taken together as of the latest audited consolidated financial statements for the Company and its Restricted Subsidiaries would constitute a Significant Subsidiary ceases to be in full force and effect (except as contemplated by the terms of the Indenture) or is declared null and void in a judicial proceeding or any Subsidiary Guarantor that is a Significant Subsidiary or group of Subsidiary Guarantors that taken together as of the latest audited consolidated financial statements of the Company and its Restricted Subsidiaries would constitute a Significant Subsidiary denies or disaffirms its obligations under the Indenture or its Subsidiary Guarantee.

All references in the Original Indenture to Sections 6.01(a), (b), (d), (e), (f), and (i) thereof shall, with respect to the Notes, be deemed to be references to Sections (b), (a), (c), (f), (g) and (i) above, respectively.

ARTICLE 5

M ODIFICATION AND W AIVER

Section 5.01 . Without Consent of Holders of Notes.

(a) The provisions of Section 9.01 of the Original Indenture shall apply to the Notes.

(b) The Company, the Subsidiary Guarantors and the Trustee may amend or supplement this Indenture or the Notes without the consent of any Holder of a Note to add Subsidiary Guarantees with respect to the Notes.

Section 5.02 . With Consent of Holders of Notes. Without the consent of each Holder affected, no amendment or waiver with respect to the Notes under this Article 5 or under Article 9 of the Original Indenture may, without the consent of each Holder of an outstanding Note affected thereby:

(a) reduce the principal amount of, the rate of interest on, or the premium, if any, payable upon the redemption or repurchase of, the Notes;

(b) change the Stated Maturity of, or any installment of principal of, or interest on, the Notes;

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(c) change the time at which any Note may be redeemed or repurchased as described above under Section 1.08; Section 3.07 or Section 3.14 of this First Supplemental Indenture;

(d) change the place or currency of payment of principal of, or premium, if any, or interest on the Notes;

(e) impair the right to institute suit for the enforcement of any payment on or with respect to the Notes on or after the Stated Maturity or prepayment date thereof;

(f) reduce the percentage in principal amount of the Notes required for modification or amendment of this Indenture or the Notes or for waiver of compliance with certain provisions of this Indenture or the Notes or for waiver of certain defaults; or

(g) modify the Subsidiary Guarantees in any manner adverse to the holders of the Notes.

The holders of at least a majority in principal amount of the Notes may, on behalf of the holders of all of the Notes, waive our compliance with specified covenants of the Indenture. The holders of at least a majority in principal amount of the Notes may, on behalf of the holders of all of the Notes, waive any past default under the Indenture with respect to the Notes, except:

(a) a default in the payment of the principal of, or premium, if any, or interest on, the Notes; or

(b) a default of a provision of the Indenture that cannot be modified or amended without the consent of the each holder of the Notes.

No amendment may be made to the subordination provisions of the Indenture that adversely affects the rights of any holder of Senior Indebtedness then outstanding unless the holders of such Senior Indebtedness (or any group or representative thereof authorized to give a consent) consent to such change. In addition, any amendment to the subordination provisions of the Indenture that adversely affects the rights of any holder of the Notes will require the consent of the holders of at least 66  ² / 3 % in aggregate principal amount of the Notes then outstanding.

ARTICLE 6

M ISCELLANEOUS P ROVISIONS

Section 6.01 . Recitals by the Company. The recitals in this First Supplemental Indenture are made by the Company only and not by the Trustee, and the Trustee assumes no responsibility for their correctness. The Trustee makes no representations as to the validity or sufficiency of this First

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Supplemental Indenture or of the Notes. The Trustee shall not be accountable for the use or application by the Company of the Notes or the proceeds thereof. All of the provisions contained in the Original Indenture in respect of the rights, privileges, immunities, powers and duties of the Trustee shall be applicable in respect of the Notes and of this First Supplemental Indenture as fully and with like effect as if set forth herein in full.

Section 6.02 . Ratification and Incorporation of Original Indenture. As supplemented hereby, the Original Indenture is in all respects ratified and confirmed, and the Original Indenture and this First Supplemental Indenture shall be read, taken and construed as one and the same instrument. The changes, modifications and supplements to the Original Indenture effected by this Supplemental Indenture shall be applicable only with respect to, and shall only govern the terms of, the Notes, which may be issued from time to time, and shall not apply to any other Securities that may be issued under the Original Indenture unless a supplemental indenture with respect to such other Securities specifically incorporates such changes, modifications and supplements. The provisions of this Supplemental Indenture shall supersede any conflicting provisions in the Original Indenture.

Section 6.03 . Executed in Counterparts. This First Supplemental Indenture may be simultaneously executed in several counterparts, each of which shall be deemed to be an original, and such counterparts shall together constitute but one and the same instrument.

Section 6.04 . NEW YORK LAW TO GOVERN. THIS FIRST SUPPLEMENTAL INDENTURE AND EACH NOTE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAW OF THE STATE OF NEW YORK.

Section 6.05 . Successors and Assigns. All covenants and agreements in this First Supplemental Indenture and each Note by the Company shall bind its successors and assigns, whether so expressed or not.

Section 6.06 . Separability. In case any provision in this First Supplemental Indenture or in any Note shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.

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IN WITNESS WHEREOF, each party hereto has caused this instrument to be signed in its name and behalf by its duly authorized officers, all as of the day and year first above written.

[Signature Page to First Supplemental Indenture]