INDENTURE, DATED AUGUST 14, 2007

EXHIBIT 4.1

ADVANCED MICRO DEVICES, INC.

as Issuer

and

WELLS FARGO BANK, NATIONAL ASSOCIATION

as Trustee

INDENTURE

Dated as of August 14, 2007

5.75% Convertible Senior Notes due 2012

ADVANCED MICRO DEVICES, INC.

Reconciliation and tie between Trust Indenture Act of 1939 and

Indenture, dated as of August 14, 2007

Note: This reconciliation and tie shall not, for any purpose, be deemed to be part of the Indenture.

TABLE OF CONTENTS

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INDENTURE dated as of August 14, 2007 between Advanced Micro Devices, Inc., a Delaware corporation, as issuer (hereinafter sometimes called the “ Company ”, as more fully set forth in Section 1.01), and Wells Fargo Bank, National Association, as trustee (hereinafter sometimes called the “ Trustee ”, as more fully set forth in Section 1.01).

WITNESSETH:

WHEREAS, for its lawful corporate purposes, the Company has duly authorized the issuance of its 5.75% Convertible Senior Notes due 2012 (the “ Notes ”) initially in an aggregate principal amount not to exceed $1,500,000,000 (or $1,725,000,000 if the Initial Purchaser (as defined below) exercises its option to purchase additional Notes pursuant to Section 2(b) of the Purchase Agreement (as defined below)), and in order to provide the terms and conditions upon which the Notes are to be authenticated, issued and delivered, the Company has duly authorized the execution and delivery of this Indenture;

WHEREAS, the Notes, the certificate of authentication to be borne by the Notes, a form of assignment, a form of the Designated Event Purchase Notice (as defined below), a form of conversion notice are to be substantially in the forms hereinafter provided for;

WHEREAS, all acts and things necessary to make the Notes, when executed by the Company and authenticated and delivered by the Trustee or a duly authorized authenticating agent, as in this Indenture provided, the valid, binding and legal obligations of the Company, and to constitute these presents a valid agreement according to its terms, have been done and performed, and the execution of this Indenture (as defined below) and the issue hereunder of the Notes have in all respects been duly authorized.

NOW, THEREFORE, THIS INDENTURE WITNESSETH:

That in order to declare the terms and conditions upon which the Notes are, and are to be, authenticated, issued and delivered, and in consideration of the premises and of the purchase and acceptance of the Notes by the holders thereof, the Company covenants and agrees with the Trustee for the equal and proportionate benefit of the respective holders from time to time of the Notes (except as otherwise provided below), as follows:

ARTICLE 1

D EFINITIONS

Section 1.01 . Definitions.

(A) 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 said Trust Indenture Act and in said Securities Act as in force at the date of the execution of this Indenture. If any provision hereof limits, qualifies or conflicts with another provision hereof which is required to be included in this Indenture by any of the provisions of the Trust Indenture Act, such required provision shall control. The words “herein,” “hereof,” “hereunder,” and words of similar import refer to this Indenture as a whole and not to any particular Article, Section or other Subdivision. The terms defined in this Article include the plural as well as the singular.

“ Additional Interest ” means all amounts, if any, payable pursuant to Section 2 of the Registration Rights Agreement.

“ Additional Shares ” shall have the meaning specified in Section 13.01(b)(i).

“ Adjustment Determination Date ” shall have the meaning specified in Section 13.04(i).

“ Adjustment Event ” shall have the meaning specified in Section 13.04(i).

“ 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 specified person means the power to direct or cause the direction of 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.

“ Board of Directors ” means the Board of Directors of the Company or a committee of such Board duly authorized to act for it hereunder.

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“ Board Resolution ” means a copy of a resolution certified by the Secretary or an Assistant Secretary of the Company to have been duly adopted by the Board of Directors, or duly authorized committee thereof (to the extent permitted by applicable law), and to be in full force and effect on the date of such certification, and delivered to the Trustee.

“ Business Day ” means, with respect to any Note, any day other than a Saturday, a Sunday or a day on which the Federal Reserve Bank of New York is closed.

“ Capital Lease ” means a lease that, in accordance with accounting principles generally accepted in the United States of America, would be recorded as a capital lease on the balance sheet of the lessee.

“ Capital Stock ” means, for any entity, any and all shares, interests, rights to purchase, warrants, options, participations or other equivalents of or interests in (however designated) stock issued by that entity.

“ close of business ” means 5:00 p.m. (New York City time).

“ Code ” means the Internal Revenue Code of 1983, as amended.

“ Commission ” means the Securities and Exchange Commission.

“ Common Stock ” means, subject to Section 13.06, shares of common stock of the Company, par value $0.01 per share, at the date of this Indenture or shares of any class or classes resulting from any reclassification or reclassifications thereof and that have no preference in respect of dividends or of amounts payable in the event of any voluntary or involuntary liquidation, dissolution or winding up of the Company and that are not subject to redemption by the Company; provided that if at any time there shall be more than one such resulting class, the shares of each such class then so issuable shall be substantially in the proportion which the total number of shares of such class resulting from all such reclassifications bears to the total number of shares of all such classes resulting from all such reclassifications.

“ Company ” means Advanced Micro Devices, Inc., a Delaware corporation, and subject to the provisions of Article 10, shall include its successors and assigns and, to the extent the obligations hereunder shall be to more than one entity pursuant to Section 13.06, shall include each of such entities.

“ Company Order ” means a written order of the Company, signed by the Company’s Chief Executive Officer, President, Vice President, Treasurer or Assistant Treasurer or Secretary or any Assistant Secretary, and delivered to the Trustee.

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“ Conversion Agent ” shall have the meaning specified in Section 3.03.

“ Conversion Date ” shall have the meaning specified in Section 13.02(c).

“ Conversion Obligation ” shall have the meaning specified in Section 13.01(a).

“ Conversion Price ” means in respect of each $1,000 principal amount of Notes, $1,000 divided by the Conversion Rate, as may be adjusted from time to time as set forth herein.

“ Conversion Rate ” shall have the meaning specified in Section 13.01(a).

“ Corporate Trust Office ” or other similar term means the principal corporate trust office of the Trustee at which at any particular time its corporate trust business shall be principally administered, which office is, at the date as of which this Indenture is dated, located at Wells Fargo Bank, National Association, 707 Wilshire Blvd, 17 ^th Floor, Los Angeles, CA 90017, Attention: Corporate Trust Services, Facsimile: 213-614-3355.

“ Custodian ” means Wells Fargo Bank, National Association, as custodian for The Depository Trust Company, with respect to the Notes in global form, or any successor entity thereto.

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

“ Defaulted Interest ” shall have the meaning specified in Section 2.04.

“ Definitive Notes ” shall have the meaning specified in Section 2.06(d).

“ Depositary ” means, with respect to the Notes issuable or issued in whole or in part in global form, the person specified in Section 2.06(d) as the Depositary with respect to such Notes, until a successor shall have been appointed and become such pursuant to the applicable provisions of this Indenture, and thereafter, “ Depositary ” shall mean or include such successor.

“ Designated Event ” will be deemed to have occurred upon a Fundamental Change or a Termination of Trading.

“ Designated Event Company Notice ” shall have the meaning specified in Section 14.01(b).

“ Designated Event Expiration Time ” shall have the meaning specified in Section 14.01(b)(viii).

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“ Designated Event Purchase Date ” shall have the meaning specified in Section 14.01(a).

“ Designated Event Purchase Notice ” shall have the meaning specified in Section 14.01(a)(i).

“ Designated Event Purchase Price ” shall have the meaning specified in Section 14.01(a).

“ Designated Institution ” shall have he meaning specified in Section 13.03(a)(i).

“ Distributed Property ” shall have the meaning specified in Section 13.04(c).

“ Effective Date ” shall have the meaning specified in Section 13.01(b)(ii).

“ Event of Default ” means, with respect to the Notes, any event specified in Section 5.01, continued for the period of time, if any, and after the giving of notice, if any, therein designated.

“ Ex-Date ” means the first date on which the shares of the Common Stock trade on the applicable exchange or in the applicable market, regular way, without the right to receive the issuance or distribution in question.

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

“ Extension Fee ” shall have the meaning specified in Section 5.01.

“ Fundamental Change ” means any transaction or event (whether by means of an exchange offer, liquidation, tender offer, consolidation, merger, combination, reclassification, recapitalization or otherwise) in connection with which more than 50% of the Common Stock is exchanged for, converted into, acquired for or constitutes solely the right to receive, consideration which is not at least 90% shares of common stock, or depositary receipts representing such shares, that are:

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“ Global Note ” shall have the meaning specified in Section 2.06(b).

“ Global Note Legend ” shall have the meaning specified in Section 2.03(d).

“ Indebtedness ” as applied to any Person, means (i) obligations, contingent or otherwise, for money borrowed (other than unamortized debt discount or premium); (ii) reimbursement and other obligations pertaining to letters of credit issued for the account of such Person; (iii) obligations under any swap, cap, collar, forward purchase contract, derivatives contract or other similar agreement pursuant to which such Person hedges risks related to interest rates, currency exchange rates, commodity prices, financial market conditions or other risks incurred by such Person in the operation of its business; (iv) obligations evidenced by bonds, debentures, promissory notes or other instruments or arrangements; (v) obligations as lessee under a Capital Lease; and (vi) obligations of such Person under any amendments, renewals, extensions, modifications and refundings of any such Indebtedness or obligations listed in clause (i), (ii), (iii), (iv) or (v) above. All indebtedness of any type described in the immediately preceding sentence which is secured by a lien upon property owned by such Person, although such Person has not assumed or become liable for the payment of such Indebtedness, shall for all purposes be deemed to be Indebtedness of such Person. All indebtedness for borrowed money incurred by any other Persons which is directly guaranteed as to payment of principal by such Person shall for all purposes be deemed to be Indebtedness of such Person, but no other contingent obligation of such Person in respect of indebtedness incurred by any other Persons shall for any purpose be deemed to be indebtedness of such Person.

“ Indenture ” means this instrument as originally executed or, if amended or supplemented as herein provided, as so amended or supplemented.

“ Initial Purchaser ” has the meaning set forth in the Purchase Agreement.

“ Interest Payment Date ” means February 15 and August 15 of each year, beginning on February 15, 2008.

“ Last Reported Sale Price ” of the Common Stock on any date means the closing sale price per share of the Common Stock (or if no closing sale price is reported, the average of the bid and ask prices or, if more than one in either case, the average of the average bid and the average ask prices) on that date as reported in composite transactions for the principal U.S. securities exchange on which the Common Stock is traded. If the Common Stock is not listed for trading on a U.S. national or regional securities exchange on the relevant date, the “ Last Reported Sale Price ” will be the last quoted bid price per share of the Common Stock in the over-the-counter market on the relevant date, as reported by the National Quotation Bureau or similar organization. If the Common Stock is not so quoted,

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the “ Last Reported Sale Price ” will be the average of the mid-point of the last bid and ask prices for the Common Stock on the relevant date from each of at least three nationally recognized independent investment banking firms, which may include the Initial Purchaser, selected by the Company for this purpose.

“ Maturity Date ” means August 15, 2012.

“ Merger Event ” shall have the meaning specified in Section 13.06.

“ Note ” or “ Notes ” means any note or notes, as the case may be, authenticated and delivered under this Indenture.

“ Noteholder ” or “ holder ,” as applied to any Note, or other similar terms (but excluding the term “ beneficial holder ”), means any person in whose name at the time a particular Note is registered on the Note Register.

“ Note Register ” shall have the meaning specified in Section 2.06(a).

“ Note Registrar ” shall have the meaning specified in Section 2.06(a).

“ Notice of Conversion ” shall have the meaning specified in Section 13.02(c).

“ Officer’s Certificate ,” when used with respect to the Company, means a certificate signed by one of the President, the Chief Executive Officer, any Vice President, the Treasurer or any Assistant Treasurer, Secretary or any Assistant Secretary of the Company, which is delivered to the Trustee. Each such certificate shall include the statements provided for in Section 15.05 if and to the extent required by the provisions of such Section. The officer giving an Officer’s Certificate pursuant to Section 5.08 shall be the principal executive, financial or accounting officer of the Company.

“ Offering Memorandum ” means the offering memorandum dated August 9, 2007 relating to the offering by the Company of the Notes.

“ open of business ” means 9:00 a.m. (New York City time).

“ Opinion of Counsel ” means an opinion in writing signed by legal counsel, who may be an employee of or counsel to the Company, or other counsel acceptable to the Trustee, which is delivered to the Trustee. Each such opinion shall include the statements provided for in Section 15.05 if and to the extent required by the provisions of such Section.

“ Outstanding ,” when used with reference to the Notes, shall, subject to the provisions of Section 7.04, mean, as of any particular time, all Notes authenticated and delivered by the Trustee under this Indenture, except:

(i) Notes theretofore canceled by the Trustee or accepted by the Trustee for cancellation,

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(ii) Notes, or portions thereof, for the payment or purchase of which monies in the necessary amount shall have been deposited in trust with the Trustee or with any Paying Agent (other than the Company) or shall have been set aside and segregated in trust by the Company (if the Company shall act as its own Paying Agent);

(iii) Notes in lieu of which, or in substitution for which, other Notes shall have been authenticated and delivered pursuant to the terms of Section 2.08 unless proof satisfactory to the Trustee is presented that any such Notes are held by protected purchasers in due course; and

(iv) Notes converted pursuant to Article 13.

“ Paying Agent ” shall have the meaning specified in Section 3.03.

“ Person ” means an individual, a corporation, a limited liability company, an association, a partnership, a joint venture, a joint stock company, a trust, an unincorporated organization or a government or an agency or a political subdivision thereof, including any syndicate or group that would be deemed to be a “person” under Section 13(d)(3) of the Exchange Act.

“ Predecessor Note ” of any particular Note means every previous Note evidencing all or a portion of the same debt as that evidenced by such particular Note; and, for the purposes of this definition, any Note authenticated and delivered under Section 2.08 in lieu of a lost, destroyed or stolen Note shall be deemed to evidence the same debt as the lost, destroyed or stolen Note that it replaces.

“ Purchase Agreement ” means the purchase agreement, dated August 9, 2007 between the Company and the Initial Purchaser relating to the purchase and sale of the Notes.

“ QIB ” means any “qualified institutional buyer” (as such term is defined in Rule 144A).

“ record date ” shall have the meaning specified in Section 2.04.

“ Record Date ” shall mean, with respect to any dividend, distribution or other transaction or event in which the holders of Common Stock have the right to receive any cash, securities or other property or in which the Common Stock (or other applicable security) is exchanged for or converted into any combination of cash, securities or other property, the date fixed for determination of stockholders entitled to receive such cash, securities or other property (whether such date is fixed by the Board of Directors, statute, contract or otherwise).

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“ Reference Property ” shall have the meaning specified in Section 13.06(b).

“ Registration Rights Agreement ” means the registration rights agreement dated as of the date hereof between the Company and the Initial Purchaser.

“ Responsible Officer ,” when used with respect to the Trustee, shall mean an officer of the Trustee in the Corporate Trust Office, having direct responsibility for the administration of this Indenture, and also, with respect to a particular matter, any other officer to whom such matter is referred because of such officer’s knowledge of and familiarity with the particular subject.

“ Restricted Securities ” shall have the meaning specified in Section 2.03.

“ Restricted Securities Legend ” shall have the meaning specified in Section 2.03.

“ Rule 144 ” means Rule 144 under the Securities Act.

“ Rule 144A ” means Rule 144A under the Securities Act.

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

“ Spin-Off ” shall have the meaning specified in Section 13.04(c).

“ Significant Subsidiary ” means such Subsidiary of the Company as meets the definition of “significant subsidiary” in Rule 1-02 of Regulation S-X promulgated by the Commission as in effect on the original date of issuance of the Notes.

“ Stock Price ” means the price paid per share of Common Stock in connection with a Fundamental Change pursuant to which Additional Shares shall be added to the Conversion Rate as set forth in Section 13.01(b) hereof, which shall be equal to (i) if holders of Common Stock receive only cash in such Fundamental Change, the cash amount paid per share of Common Stock and (ii) in all other cases, the average of the Last Reported Sale Prices of the Common Stock over the five consecutive Trading Day period ending on the Trading Day immediately preceding the Effective Date of such Fundamental Change.

“ Subsidiary ” of the Company means (i) a corporation a majority of whose Capital Stock with voting power, under ordinary circumstances, to elect directors

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is at the time, directly or indirectly, owned by the Company, by the Company and one or more Subsidiaries of the Company or by one or more Subsidiaries of the Company or (ii) any other Person (other than a corporation) in which the Company, one or more Subsidiaries of the Company or the Company and one or more Subsidiaries of the Company, directly or indirectly, at the date of determination thereof, has greater than a fifty percent (50%) ownership interest.

“ Successor Company ” shall have the meaning specified in Section 10.01(a).

“ Termination of Trading ” will be deemed to have occurred if the Common Stock is neither listed for trading on a U.S. national securities exchange nor approved for quotation on a U.S. system of automated dissemination of quotations of securities prices similar to the NASDAQ Global Select Market prior to its designation as a national securities exchange.

“ Trading Day ” means a day during which trading in the Common Stock generally occurs. If the Common Stock (or other security for which a closing sale price must be determined) is not listed for trading on a U.S. national or regional securities exchange on the relevant date, “ Trading Date ” means a Business Day.

“ transfer ” shall have the meaning specified in Section 2.03.

“ Trust Indenture Act ” means the Trust Indenture Act of 1939, as amended, as it was in force at the date of execution of this Indenture; provided however , that in the event the Trust Indenture Act of 1939 is amended after the date hereof, the term “ Trust Indenture Act ” shall mean, to the extent required by such amendment, the Trust Indenture Act of 1939, as so amended.

“ Trustee ” means Wells Fargo Bank, National Association, and its successors and any corporation resulting from or surviving any consolidation or merger to which it or its successors may be a party and any successor trustee at the time serving as successor trustee hereunder.

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 Notes.

“ indenture security holder ” means a holder.

“ indenture to be qualified ” means this Indenture.

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

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

All other terms in this Indenture that are defined by the Trust Indenture Act, defined by it by reference to another statute or defined by Commission rule have the meanings assigned to them by such definitions. If any provision hereof limits, qualifies or conflicts with another provision hereof which is required to be included in this Indenture by the Trust Indenture Act, such required provision shall control.

ARTICLE 2

I SSUE , D ESCRIPTION , E XECUTION , R EGISTRATION AND E XCHANGE OF N OTES

Section 2.01 . Designation and Amount. The Notes shall be designated as the “5.75% Convertible Senior Notes due 2012.” The aggregate principal amount of the Notes that may be authenticated and delivered under this Indenture is initially limited to $1,500,000,000 (or $1,725,000,000 if the Initial Purchaser exercises its option to purchase additional Notes pursuant to Section 2(b) of the Purchase Agreement), subject to Section 2.13 and except for Notes authenticated and delivered upon registration or transfer of, or in exchange for, or in lieu of other Notes pursuant to Section 2.06, Section 2.08, Section 9.04 and Section 13.02.

Section 2.02 . Form of Notes. The Notes and the Trustee’s certificate of authentication to be borne by such Notes shall be substantially in the form set forth in Exhibit A , with such applicable legends as are provided for in Section 2.03.

Any of the Notes may have such letters, numbers or other marks of identification and such notations, legends or endorsements as the officers executing the same may approve (execution thereof to be conclusive evidence of such approval) and as are not inconsistent with the provisions of this Indenture, or as may be required to comply with any law or with any rule or regulation made pursuant thereto or with any rule or regulation of any securities exchange or automated quotation system on which the Notes may be listed or designated for issuance, or to conform to usage.

The Notes shall be issued initially in the form of one or more permanent Global Notes with the applicable legends as provided in Section 2.03. Each Global Note shall represent such principal amount of the outstanding Notes as shall be specified therein and shall provide that it shall represent the aggregate principal amount of outstanding Notes from time to time endorsed thereon and that the aggregate principal amount of outstanding Notes represented thereby may

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from time to time be increased or reduced to reflect purchases, conversions, transfers or exchanges permitted hereby. Any endorsement of a Global Note to reflect the amount of any increase or decrease in the amount of outstanding Notes represented thereby shall be made by the Trustee or the Custodian, at the direction of the Trustee, in such manner and upon instructions given by the holder of such Notes in accordance with this Indenture. Payment of principal and accrued and unpaid interest on the Global Note shall be made to the holder of such Note on the date of payment, unless a record date or other means of determining holders eligible to receive payment is provided for herein.

The terms and provisions contained in the forms of Note attached as Exhibit A hereto are incorporated herein and shall constitute, and are hereby expressly made, a part of this Indenture and to the extent applicable, the Company and the Trustee, by their execution and delivery of this Indenture, expressly agree to such terms and provisions and to be bound thereby.

Section 2.03 . Legends. Each Note issued hereunder and each Common Stock certificate representing shares of Common Stock issued upon conversion of such Note (collectively, the “ Restricted Securities ”) shall, upon issuance, bear the legend set forth in Section 2.03(a) or 2.03(b), as applicable (each a “ Restricted Securities Legend ”), and such legend shall not be removed except as provided in Section 2.03(c). Each such Restricted Security that bears or is required to bear the applicable Restricted Securities Legend shall be subject to the restrictions on transfer set forth in this Section 2.03 (including the Restricted Securities Legend set forth below), and the holder of each such Restricted Security, by such holder’s acceptance thereof, shall be deemed to have agreed to be bound by all such restrictions on transfer.

As used in Section 2.03, the term “ transfer ” encompasses any sale, pledge, transfer or other disposition whatsoever of any Restricted Security.

(A) Restricted Securities Legend for the Notes . Except as provided in Section 2.03(c), any certificate evidencing such Note (and all Notes issued in exchange therefor or substitution thereof, shall bear a Restricted Securities Legend in substantially the following form:

THIS SECURITY AND THE SHARES OF ADVANCED MICRO DEVICES, INC. (THE “COMPANY”) COMMON STOCK (“COMMON STOCK”) ISSUABLE UPON CONVERSION OF THIS SECURITY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES LAWS. NEITHER THIS SECURITY, THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN OR THEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED,

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PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION. THE HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE HEREOF, (1) AGREES TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE “RESALE RESTRICTION TERMINATION DATE”) THAT IS TWO YEARS AFTER THE LAST ORIGINAL ISSUE DATE HEREOF ONLY (A) TO THE COMPANY OR ANY SUBSIDIARY THEREOF, (B) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A, TO A PERSON IT REASONABLY BELIEVES IS A “QUALIFIED INSTITUTIONAL BUYER” AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHICH NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (C) PURSUANT TO A REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, OR (D) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE RIGHTS OF THE COMPANY AND THE TRUSTEE PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO CLAUSE (D) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM, AND IN EACH OF THE FOREGOING CASES WHERE REGISTRATION OR TRANSFER OF THIS SECURITY IS REQUIRED, A CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON THE OTHER SIDE OF THIS SECURITY COMPLETED AND DELIVERED BY THE TRANSFEROR TO THE TRUSTEE AND (2) AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THIS NOTE IS TRANSFERRED A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. THIS LEGEND WILL BE REMOVED AFTER THE RESALE RESTRICTION TERMINATION DATE. THE INDENTURE CONTAINS A PROVISION REQUIRING THE TRUSTEE TO REFUSE TO REGISTER ANY TRANSFER OF THIS NOTE IN VIOLATION OF THE FOREGOING RESTRICTION. IN ANY CASE, THE HOLDER HEREOF WILL NOT, DIRECTLY OR INDIRECTLY ENGAGE IN ANY HEDGING TRANSACTIONS WITH REGARD TO THIS SECURITY OR THE COMMON STOCK EXCEPT AS PERMITTED UNDER THE SECURITIES ACT.

(B) Restricted Securities Legend for the Common Stock Issued Upon Conversion of the Notes . Each stock certificate representing Common Stock

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issued upon conversion of Notes bearing a Restricted Securities Legend will, subject to the availability of a Shelf Registration Statement (as defined in the Registration Rights Agreement) and registration thereunder as set forth in the Registration Rights Agreement, bear the following legend:

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), AND ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT AS SET FORTH IN THE FOLLOWING SENTENCE. BY ITS ACQUISITION HEREOF, THE HOLDER AGREES (1) THAT IT WILL NOT RESELL OR OTHERWISE TRANSFER THE SECURITY EVIDENCED HEREBY, EXCEPT (A) TO THE ISSUER; (B) UNDER A REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT; (C) TO A PERSON THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER (AS DEFINED IN RULE 144A ADOPTED UNDER THE SECURITIES ACT) THAT IS PURCHASING FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF ANOTHER QUALIFIED INSTITUTIONAL BUYER AND TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, ALL IN COMPLIANCE WITH RULE 144A (IF AVAILABLE); OR (D) UNDER ANY OTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT; AND (2) IT WILL, PRIOR TO ANY TRANSFER OF THIS SECURITY FURNISH TO THE TRANSFER AGENT AND THE ISSUER SUCH CERTIFICATIONS, LEGAL OPINIONS OR OTHER INFORMATION AS MAY BE REQUIRED TO CONFIRM THAT SUCH TRANSFER IS BEING MADE PURSUANT TO AN EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT.

(C) Removal of the Restricted Securities Legends . The Restricted Securities Legend may be removed from any Note or any Common Stock certificate representing shares of the Common Stock issued upon conversion of any Note if there is delivered to the Company such satisfactory evidence, which may include an opinion of independent counsel, as may be reasonably required by the Company, that neither such legend nor the restrictions on transfer set forth therein are required to ensure that transfers of such Note or shares of the Common Stock issued upon conversion of Notes, as the case may be, will not violate the registration requirements of the Securities Act or the qualification requirements under any state securities laws. Upon provision of such satisfactory evidence, at the written direction of the Company, (x) in the case of a Note, the Trustee shall authenticate and deliver in exchange for such Note another Note or Notes having an equal aggregate principal amount that does not bear such legend or (y) in the case of a Common Stock certificate representing shares of the Common Stock, the

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transfer agent for the Common Stock shall authenticate and deliver in exchange for the Common Stock certificate or certificates representing such shares of Common Stock bearing such legend, one or more new Common Stock certificates representing a like aggregate number of shares of Common Stock that do not bear such legend. If the Restricted Securities Legend has been removed from a Note or Common Stock certificates representing shares of the Common Stock issued upon conversion of any Note as provided above, no other Note issued in exchange for all or any part of such Note, or no other Common Stock certificates issued in exchange for such Common Stock, shall bear such legend, unless the Company has reasonable cause to believe that such other Note is a “restricted security” (or such shares of Common Stock are “restricted securities”) within the meaning of Rule 144 and instructs the Trustee in writing to cause a Restricted Securities Legend to appear thereon.

Any Note (or Note issued in exchange or substitution therefor) as to which the conditions for removal of the Restricted Securities Legend set forth in Section 2.03(a) as set forth therein have been satisfied may, upon surrender of such Note for exchange to the Note Registrar in accordance with the provisions of Section 2.07, be exchanged for a new Note or Notes, of like tenor and aggregate principal amount, which shall not bear the Restricted Securities Legend required by Section 2.03(a).

Any Common Stock certificate representing shares of Common Stock issued upon conversion of any Note as to which the conditions for removal of the Restricted Securities Legend set forth in Section 2.03(b) have been satisfied may, upon surrender of the Common Stock certificates representing such shares of Common Stock for exchange in accordance with the procedures of the transfer agent for the Common Stock, be exchanged for a new Common Stock certificate or certificates representing a like aggregate number of shares of Common Stock, which shall not bear the Restricted Securities Legend.

(D) Global Note Legend . Each Global Note shall also bear the following legend (the “ Global Note Legend ”) on the face thereof:

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), NEW YORK, NEW YORK, TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY

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OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

TRANSFERS OF THIS GLOBAL NOTE SHALL BE LIMITED TO TRANSFERS IN WHOLE, BUT NOT IN PART, TO NOMINEES OF DTC OR TO A SUCCESSOR THEREOF OR SUCH SUCCESSOR’S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL NOTE SHALL BE LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN THE INDENTURE REFERRED TO IN THE TERMS OF THE NOTE ATTACHED HERETO.

(E) Legend for Definitive Notes . Definitive Notes, in addition to the legend set forth in Section 2.03(a), will also bear a legend substantially in the following form:

THIS SECURITY WILL NOT BE ACCEPTED IN EXCHANGE FOR A BENEFICIAL INTEREST IN A GLOBAL NOTE UNLESS THE HOLDER OF THIS SECURITY, SUBSEQUENT TO SUCH EXCHANGE, WILL HOLD NO NOTES.

Section 2.04 . Date and Denomination of Notes; Payments on the Notes. The Notes shall be issuable initially in fully registered form without coupons in denominations of $1,000 principal amount and integral multiples thereof. Each Note shall be dated the date of its authentication and shall bear interest from the date specified on the face of the form of Note attached as Exhibit A hereto, as applicable. Interest on the Notes (including any Additional Interest) shall be computed on the basis of a 360-day year comprised of twelve (12) 30-day months.

If any Interest Payment Date (other than an Interest Payment Date coinciding with the Maturity Date or required Designated Event Purchase Date) of a Note falls on a day that is not a Business Day, such Interest Payment Date will be postponed to the next succeeding Business Day. If the Maturity Date or required Designated Event Purchase Date would fall on a day that is not a Business Day, the required payment of interest (including any Additional Interest), if any, and principal, will be made on the next succeeding Business Day and no interest on such payment will accrue for the period from and after the Maturity Date or required Designated Event Purchase Date to such next succeeding Business Day.

The Person in whose name any Note (or its Predecessor Note) is registered on the Note Register at the close of business on any record date with respect to any Interest Payment Date shall be entitled to receive the interest (including any Additional Interest) payable on such Interest Payment Date. Interest shall be

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payable at the office of the Company maintained by the Company for such purpose in Minneapolis, Minnesota. The Company shall pay interest (including Additional Interest, if any) (i) on any Global Note in immediately available funds to the account of the Depositary or its nominee or (ii) on Notes in certificated form (x) to holders having an aggregate principal amount of $5,000,000 or less, by check mailed to the holders of these Notes or (y) to holders having an aggregate principal amount of more than $5,000,000, either by check mailed to each holder or, upon application by a holder to the Note Registrar not later than the relevant record date, by wire transfer in immediately available funds to that holder’s account within the United States, which application shall remain in effect until the holder notifies, in writing, the Note Registrar to the contrary. The term “ record date ” with respect to any Interest Payment Date shall mean the February 1 or August 1 preceding the applicable February 15 or August 15 Interest Payment Date, respectively.

Any interest on any Note which is payable, but is not punctually paid or duly provided for, on any Interest Payment Date (herein called “ Defaulted Interest ”) shall forthwith cease to be payable to the Noteholder on the relevant record date by virtue of his having been such Noteholder, and such Defaulted Interest shall be paid by the Company, at its election in each case, as provided in clause (1) or (2) below:

(1) The Company may elect to make payment of any Defaulted Interest to the Persons in whose names the Notes (or their respective Predecessor Notes) 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 Note and the date of the proposed payment (which shall be not less than twenty-five (25) days after the receipt by the Trustee of such notice, unless the Trustee shall consent to an earlier date), and at the same time the Company shall deposit with the Trustee an amount of money equal to the aggregate amount to be paid in respect of such Defaulted Interest or shall make arrangements satisfactory to the Trustee for such deposit on or 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 Company shall fix a special record date for the payment of such Defaulted Interest which shall be not more than fifteen (15) days and not less than ten (10) days prior to the date of the proposed payment, and not less than ten (10) days after the receipt by the Trustee of the notice of the proposed payment. The Company shall promptly notify the Trustee in writing of such special record date and the Trustee, 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 at his address as it appears in the Note Register, not less than ten (10) days prior to such special record date. Notice of the proposed payment of such Defaulted Interest

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and the special record date therefor having been so mailed, such Defaulted Interest shall be paid to the Persons in whose names the Notes (or their respective Predecessor Notes) are registered at the close of business on such special record date and shall no longer be payable pursuant to the following clause (2) of this Section 2.04.

(2) The Company may make payment of any Defaulted Interest in any other lawful manner not inconsistent with the requirements of any securities exchange or automated quotation system on which the Notes may be listed or designated for issuance, and upon such notice as may be required by such exchange or automated quotation system, 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.

Section 2.05 . Execution, Authentication and Delivery of Notes. The Notes shall be signed in the name and on behalf of the Company by the manual or facsimile signature of its Chairman or Vice-Chairman of the Board of Directors, Chief Executive Officer, President or any of its Vice Presidents.

At any time and from time to time after the execution and delivery of this Indenture, the Company may deliver Notes executed by the Company to the Trustee for authentication, together with a Company Order for the authentication and delivery of such Notes, and the Trustee in accordance with such Company Order shall authenticate and deliver such Notes, without any further action by the Company hereunder.

Only such Notes as shall bear thereon a certificate of authentication substantially in the form set forth on the form of Note attached as Exhibit A hereto, executed manually or by facsimile by the Trustee (or an authenticating agent appointed by the Trustee as provided by Section 15.10), shall be entitled to the benefits of this Indenture or be valid or obligatory for any purpose. Such certificate by the Trustee (or such an authenticating agent) upon any Note executed by the Company shall be conclusive evidence that the Note so authenticated has been duly authenticated and delivered hereunder and that the holder is entitled to the benefits of this Indenture.

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

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The Trustee shall have the right to decline to authenticate and deliver any Notes under this Section if the Trustee, being advised by counsel of national reputation, determines that such action may not lawfully be taken or if the Trustee in good faith shall determine that such action would expose the Trustee to personal liability to existing Noteholders.

Section 2.06 . Exchange and Registration of Transfer of Notes; Transfer Generally; Depositary. (a) The Company shall cause to be kept at the Corporate Trust Office a register for the Notes (the register maintained in such office and in any other office or agency of the Company designated pursuant to Section 3.02 being herein sometimes collectively referred to as the “ Note Register ”) in which, subject to such reasonable regulations as it may prescribe, the Company shall provide for the registration of Notes and of transfers of Notes. Such register shall be in written form or in any form capable of being converted into written form within a reasonable period of time. The Trustee is hereby appointed “ Note Registrar ” for the purpose of registering Notes and transfers of Notes as herein provided. The Company may appoint one or more co-registrars in accordance with Section 3.03.

Upon surrender for registration of transfer of any Note to the Note Registrar or any co-registrar, and satisfaction of the requirements for such transfer set forth in this Section 2.06, the Company shall execute, and the Trustee shall authenticate and deliver, in the name of the designated transferee or transferees, one or more new Notes of any authorized denominations and of a like aggregate principal amount and bearing such restrictive legends as may be required by this Indenture.

Notes may be exchanged for other Notes of any authorized denominations and of a like aggregate principal amount, upon surrender of such Notes to be exchanged at any such office or agency maintained by the Company pursuant to Section 3.03. Whenever any Notes are so surrendered for exchange, the Company shall execute, and the Trustee shall authenticate and deliver, the Notes which the Noteholder making the exchange is entitled to receive, bearing registration numbers not contemporaneously outstanding.

All Notes presented or surrendered for registration of transfer or for exchange, purchase or conversion shall (if so required by the Company, the Trustee, the Note Registrar or any co-registrar) be duly endorsed, or be accompanied by a written instrument or instruments of transfer in form satisfactory to the Company and duly executed, by the Noteholder thereof or his attorney-in-fact duly authorized in writing.

No service charge shall be charged to the Noteholder for any exchange or registration of transfer of Notes, but the Company or the Trustee may require payment of a sum sufficient to cover any tax, assessments or other governmental charges that may be imposed in connection therewith.

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None of the Company, the Trustee, the Note Registrar or any co-registrar shall be required to exchange or register a transfer of (a) any Notes surrendered for conversion or, if a portion of any Note is surrendered for conversion, such portion thereof surrendered for conversion or (b) any Notes, or a portion of any Note, surrendered for purchase (and not withdrawn) except in accordance with Article 13 for conversion and Article 14 for purchase hereof, respectively.

All Notes issued upon any registration of transfer or exchange of Notes in accordance with this Indenture shall be the valid obligations of the Company, evidencing the same debt, and entitled to the same benefits under this Indenture as the Notes surrendered upon such registration of transfer or exchange.

(B) So long as the Notes are eligible for book-entry settlement with the Depositary, unless otherwise required by law, all Notes shall be represented by one or more Notes in global form (each, a “ Global Note ”) registered in the name of the Depositary or the nominee of the Depositary. The transfer and exchange of beneficial interests in a Global Note, which does not involve the issuance of a Definitive Note, shall be effected through the Depositary (but not the Trustee or the Custodian) in accordance with this Indenture (including the restrictions on transfer set forth herein) and the procedures of the Depositary therefor.

(C) Any Global Note shall initially bear (i) the Restricted Securities Legend set forth in Section 2.03(a) and (ii) the Global Note Legend set forth in Section 2.03(d), and may be endorsed with or have incorporated in the text thereof such legends or recitals or changes not inconsistent with the provisions of this Indenture as may be required by the Custodian, the Depositary or by the National Association of Securities Dealers, Inc. to comply with any applicable law or any regulation thereunder or with the rules and regulations of any securities exchange or automated quotation system upon which the Notes may be listed or traded or designated for issuance or to conform with any usage with respect thereto, or to indicate any special limitations or restrictions to which any particular Notes are subject.

Notwithstanding any other provisions of this Indenture, a Global Note may not be transferred as a whole or in part 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 by the Depositary or any such nominee to a successor Depositary or a nominee of such successor Depositary.

(D) The Depositary shall be a clearing agency registered under the Exchange Act. The Company initially appoints The Depository Trust Company to act as Depositary with respect to each Global Note. Initially, each Global Note

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shall be issued to the Depositary, registered in the name of Cede & Co., as the nominee of the Depositary, and deposited with the Trustee as custodian for Cede & Co.

If at any time the Depositary for a Global Note (i) notifies the Company that it is unwilling or unable to continue as Depositary for such Note or (ii) ceases to be registered as a clearing agency under the Exchange Act, the Company may appoint a successor Depositary with respect to such Note. If (1) a successor Depositary for such Global Note is not appointed by the Company within ninety (90) days after the Company receives such notice or the Depositary ceasing to be a registered clearing agency, (2) the Company, at its option, notifies the Trustee that it elects to cause the issuance of Notes in definitive form (“ Definitive Notes ”) in exchange for all or any part of the Notes represented by a Global Note, subject to the procedures of the Depositary, or (3) an Event of Default has occurred and is continuing and the Note Registrar has received a request from the beneficial owner of a Note for the issuance of Definitive Notes in exchange for a Global Note, the Company will execute, and the Trustee, upon receipt of an Officer’s Certificate for the authentication and delivery of Definitive Notes, will authenticate and deliver Definitive Notes in an aggregate principal amount equal to the principal amount of such Global Note, in exchange for such Global Note, and upon delivery of the Global Note to the Trustee such Global Note shall be canceled.

Definitive Notes issued in exchange for all or a part of the Global Note pursuant to this Section 2.06(d) shall be registered in such names and in such authorized denominations as the Depositary, pursuant to instructions from its direct or indirect participants or otherwise, shall instruct the Trustee. Upon execution and authentication, the Trustee shall deliver such Definitive Notes to the persons in whose names such Definitive Notes are so registered.

At such time as all interests in a Global Note have been converted, canceled, purchased or transferred, such Global Note shall be, upon receipt thereof, canceled by the Trustee in accordance with standing procedures and instructions existing between the Depositary and the Custodian. At any time prior to such cancellation, if any interest in a Global Note is exchanged for Definitive Notes, converted, canceled, purchased or transferred to a transferee who receives Definitive Notes therefor or any Definitive Note is exchanged or transferred for part of such Global Note, the principal amount of such Global Note shall, in accordance with the standing procedures and instructions existing between the Depositary and the Custodian, be appropriately reduced or increased, as the case may be, and an endorsement shall be made on such Global Note, by the Trustee or the Custodian, at the direction of the Trustee, to reflect such reduction or increase.

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Section 2.07 . Special Transfer Provisions. Unless a Note is no longer a Restricted Security, the following provisions shall apply to any sale, pledge or other transfer of such Notes:

(a) Transfer of Notes to a QIB . The following provisions shall apply with respect to the registration of any proposed transfer of Notes to a QIB:

(i) If the Notes to be transferred consist of a beneficial interest in the Global Notes, the transfer of such interest may be effected only through the book-entry systems maintained by The Depositary Trust Company.

( II ) If the Notes to be transferred consist of Definitive Notes, the Note Registrar shall register the transfer if such transfer is being made by a proposed transferor who has checked the box provided for on the form of Note stating (or has otherwise advised the Company and the Registrar in writing) that the sale has been made in compliance with the provisions of Rule 144A to a transferee who has signed a certification stating or has otherwise advised the Company and the Note Registrar in writing that:

(A) it is purchasing the Notes for its own account or an account with respect to which it exercises sole investment discretion;

(B) it and any such account is a QIB within the meaning of Rule 144A;

(C) it is aware that the sale to it is being made in reliance on Rule 144A;

(D) it acknowledges that it has received such information regarding the Company as it has requested pursuant to Rule 144A or has determined not to request such information; and

(E) it is aware that the transferor is relying upon its foregoing representations in order to claim the exemption from registration provided by Rule 144A.

(b) General . By its acceptance of any Note bearing the Restricted Securities Legend, each holder of such Note acknowledges the restrictions on transfer of such Note set forth in this Indenture and agrees that it will transfer such Note only as provided in this Indenture. The Note Registrar shall not register a transfer of any Note unless such transfer complies with the restrictions on transfer of such Note set forth in this Indenture. The Note Registrar shall be

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entitled to receive and rely on written instructions from the Company verifying that such transfer complies with such restrictions on transfer. In connection with any transfer of Notes (other than a transfer to the Company (or a Subsidiary of the Company) or a transfer pursuant to Rule 144A or pursuant to a registration statement declared effective under the Securities Act), each holder agrees by its acceptance of the Notes to furnish the Note Registrar or the Company such certifications, legal opinions or other information as either of them may reasonably require to confirm that such transfer is being made pursuant to an exemption from, or a transaction not subject to, the registration requirements of the Securities Act; provided that the Note Registrar shall not be required to determine (but may rely on a determination made by the Company with respect to) the sufficiency of any such certifications, legal opinions or other information.

The Note Registrar shall retain copies of all certifications, letters, notices and other written communications received pursuant to Section 2.06 hereof or this Section 2.07. The Company shall have the right to inspect and make copies of all such letters, notices or other written communications at any reasonable time upon the giving of reasonable written notice to the Note Registrar.

Section 2.08 . Mutilated, Destroyed, Lost or Stolen Notes. In case any Note shall become mutilated or be destroyed, lost or stolen, the Company in its discretion may execute, and upon its written request the Trustee or an authenticating agent appointed by the Trustee shall authenticate and deliver, a new Note, bearing a number not contemporaneously outstanding, in exchange and substitution for the mutilated Note, or in lieu of and in substitution for the Note so destroyed, lost or stolen. In every case the applicant for a substituted Note shall furnish to the Company, to the Trustee and, if applicable, to such authenticating agent such security or indemnity as may be required by them to save each of them harmless from any loss, liability, cost or expense caused by or connected with such substitution, and, in every case of destruction, loss or theft, the applicant shall also furnish to the Company, to the Trustee and, if applicable, to such authenticating agent evidence to their satisfaction of the destruction, loss or theft of such Note and of the ownership thereof.

The Trustee or such authenticating agent may authenticate any such substituted Note and deliver the same upon the receipt of such security or indemnity as the Trustee, the Company and, if applicable, such authenticating agent may require. Upon the issuance of any substituted Note, the Company or the Trustee may require the payment by the holder of a sum sufficient to cover any tax, assessment or other governmental charge that may be imposed in relation thereto and any other expenses connected therewith. In case any Note which has matured or is about to mature or has been surrendered for purchase upon a Designated Event or is about to be converted into Common Stock shall become mutilated or be destroyed, lost or stolen, the Company may, in its sole discretion, instead of issuing a substitute Note, pay or authorize the payment of or convert or

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authorize the conversion of the same (without surrender thereof except in the case of a mutilated Note), as the case may be, if the applicant for such payment or conversion shall furnish to the Company, to the Trustee and, if applicable, to such authenticating agent such security or indemnity as may be required by them to save each of them harmless for any loss, liability, cost or expense caused by or connected with such substitution, and, in every case of destruction, loss or theft, evidence satisfactory to the Company, the Trustee and, if applicable, any Paying Agent or Conversion Agent evidence of their satisfaction of the destruction, loss or theft of such Note and of the ownership thereof.

Every substitute Note issued pursuant to the provisions of this Section 2.08 by virtue of the fact that any Note is destroyed, lost or stolen shall constitute an additional contractual obligation of the Company, whether or not the destroyed, lost or stolen Note shall be found at any time, and shall be entitled to all the benefits of (but shall be subject to all the limitations set forth in) this Indenture equally and proportionately with any and all other Notes duly issued hereunder. To the extent permitted by law, all Notes shall be held and owned upon the express condition that the foregoing provisions are exclusive with respect to the replacement or payment or conversion or purchase of mutilated, destroyed, lost or stolen Notes 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 or conversion of negotiable instruments or other securities without their surrender.

Section 2.09 . Temporary Notes. Pending the preparation of Notes in certificated form, the Company may execute and the Trustee or an authenticating agent appointed by the Trustee shall, upon written request of the Company, authenticate and deliver temporary Notes (printed or lithographed). Temporary Notes shall be issuable in any authorized denomination, and substantially in the form of the Notes in certificated form but with such omissions, insertions and variations as may be appropriate for temporary Notes, all as may be determined by the Company. Every such temporary Note shall be executed by the Company and authenticated by the Trustee or such authenticating agent upon the same conditions and in substantially the same manner, and with the same effect, as the Notes in certificated form. Without unreasonable delay the Company will execute and deliver to the Trustee or such authenticating agent Notes in certificated form (other than any Global Note) and thereupon any or all temporary Notes (other than any Global Note) may be surrendered in exchange therefor, at each office or agency maintained by the Company pursuant to Section 3.02 and the Trustee or such authenticating agent shall authenticate and deliver in exchange for such temporary Notes an equal aggregate principal amount of Notes in certificated form. Such exchange shall be made by the Company at its own expense and without any charge therefor. Until so exchanged, such temporary Notes shall in all respects be entitled to the same benefits and subject to the same limitations under this Indenture as Notes in certificated form authenticated and delivered hereunder.

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Section 2.10 . Restriction on Resale. Any Notes or shares of Common Stock issued upon the conversion of Notes that are purchased or owned by the Company or any Affiliate thereof may not be resold by the Company or such Affiliate unless registered under the Securities Act or resold pursuant to an exemption from the registration requirements of the Securities Act in a transaction that results in such Notes or shares of Common Stock, as the case may be, no longer being “restricted securities” (as defined under Rule 144).

Section 2.11 . Cancellation of Notes Paid, Etc. All Notes surrendered for the purpose of payment, purchase, conversion, exchange or registration of transfer, shall, if surrendered to the Company or any Paying Agent or any Note Registrar or any Conversion Agent, be surrendered to the Trustee and promptly canceled by it, or, if surrendered to the Trustee, shall be promptly canceled by it, and no Notes shall be issued in lieu thereof except as expressly permitted by any of the provisions of this Indenture. The Trustee shall destroy canceled Notes in accordance with its customary procedures and, after such destruction, shall deliver a certificate of such destruction to the Company, at the Company’s written request. If the Company shall acquire any of the Notes, such acquisition shall not operate as satisfaction of the Indebtedness represented by such Notes unless and until the same are delivered to the Trustee for cancellation.

Section 2.12 . CUSIP Numbers. The Company in issuing the Notes may use “CUSIP” numbers (if then generally in use), and, if so, the Trustee shall use “CUSIP” numbers in Company Notices as a convenience to holders of the Notes; provided , that any such notice may state that no representation is made as to the correctness of such numbers either as printed on the Notes or Company Notice and that reliance may be placed only on the other identification numbers printed on the Notes. The Company will promptly notify the Trustee in writing of any change in the “CUSIP” numbers.

Section 2.13 . Additional Notes, Purchases. The Company may, without the consent of the Noteholders and notwithstanding Section 2.01, reopen the Notes and issue additional Notes hereunder with the same terms and with the same CUSIP number as such Notes initially issued hereunder in an unlimited aggregate principal amount, which will form the same series with the Notes initially issued hereunder so long as such additional Notes are fungible with such Notes initially issued hereunder for U.S. federal income tax purposes. The Company may also from time to time purchase Notes in tender offers, open market purchases or negotiated transactions without prior notice to Noteholders.

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ARTICLE 3

P ARTICULAR C OVENANTS OF THE C OMPANY

Section 3.01 . Payment of Principal, Interest and Extension Fee. The Company covenants and agrees that it will cause to be paid the principal of, accrued and unpaid interest (including any Additional Interest) on, each of the Notes and if applicable, payment of the Extension Fee, Conversion Obligation and Additional Shares, at the places, at the respective times and in the manner provided herein and in the Notes.

Section 3.02 . Additional Interest. If Additional Interest is payable by the Company pursuant to the Registration Rights Agreement, the Company shall deliver to the Trustee an Officer’s Certificate to that effect stating (i) the amount of such Additional Interest that is payable and (ii) the date on which such Additional Interest is payable. Unless and until a Responsible Officer receives such a certificate, the Trustee may assume without inquiry that no Additional Interest is payable. If the Company has paid Additional Interest directly to the persons entitled to it, the Company shall deliver to the Trustee an Officer’s Certificate setting forth the particulars of such payment.

Section 3.03 . Maintenance of Office or Agency. The Company will maintain an office or agency where the Notes may be surrendered for registration of transfer or exchange or for presentation for payment, redemptions or purchase (“ Paying Agent ”) or for conversion (“ Conversion Agent ”) and where notices and demands to or upon the Company in respect of the Notes 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 not designated or appointed by the Trustee. 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 or the office or agency of the Trustee.

The Company may also from time to time designate one or more other offices or agencies where the Notes may be presented or surrendered for any or all such purposes and may from time to time rescind such designations; provided that no such designation or rescission shall in any manner relieve the Company of its obligation to maintain an office or agency for such purposes. The Company will give prompt written notice to the Trustee of any such designation or rescission and of any change in the location of any such other office or agency. The terms Paying Agent and Conversion Agent include any such additional or other offices or agencies, as applicable.

The Company hereby initially designates the Trustee as the Paying Agent, Note Registrar, Custodian and Conversion Agent and the Corporate Trust Office

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and the office or agency of the Trustee in Minneapolis, Minnesota shall be considered as one such office or agency of the Company for each of the aforesaid purposes.

So long as the Trustee is the Note Registrar, the Trustee agrees to mail, or cause to be mailed, the notices set forth in Section 6.10(a) and the third paragraph of Section 6.11.

Section 3.04 . Appointments to Fill Vacancies in Trustee’s Office. The Company, whenever necessary to avoid or fill a vacancy in the office of Trustee, will appoint, in the manner provided in Section 6.10, a Trustee, so that there shall at all times be a Trustee hereunder.

Section 3.05 . Provisions as to Paying Agent. (a) If the Company shall appoint a Paying Agent other than the Trustee or if the Trustee shall appoint such a Paying Agent, the Company will cause such Paying Agent 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 3.05:

(i) that it will hold all sums held by it as such agent for the payment of the principal of, accrued and unpaid interest (including any Additional Interest) on, and any Extension Fee with respect to the Notes (whether such sums have been paid to it by the Company or by any other obligor on the Notes) in trust for the benefit of the holders of the Notes;

(ii) that it will give the Trustee notice of any failure by the Company (or by any other obligor on the Notes) to make any payment of the principal of, accrued and unpaid interest (including any Additional Interest) on, or any Extension Fee with respect to the Notes when the same shall be due and payable; and

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

The Company shall, on or before each due date of the principal of, accrued and unpaid interest (including any Additional Interest) on, or any Extension Fee with respect to the Notes, deposit with the Paying Agent a sum sufficient to pay such principal, accrued and unpaid interest or Extension Fee and (unless such Paying Agent is the Trustee) the Company will promptly notify the Trustee in writing of any failure to take such action, provided that if such deposit is made on the due date, such deposit must be received by the Paying Agent by 11:00 a.m., New York City time, on such date.

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(b) If the Company shall act as its own Paying Agent, it will, on or before each due date of the principal of, accrued and unpaid interest (including any Additional Interest) on, or any Extension Fee with respect to the Notes, set aside, segregate and hold in trust for the benefit of the holders of the Notes a sum sufficient to pay such principal, accrued and unpaid interest or Extension Fee so becoming due and will notify the Trustee in writing of any failure to take such action and of any failure by the Company (or any other obligor under the Notes) to make any payment of the principal of, accrued and unpaid interest on or any Extension Fee with respect to the Notes, when the same shall become due and payable.

(c) Anything in this Section 3.05 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 the Company or any Paying Agent hereunder as required by this Section 3.05, such sums to be held by the Trustee upon the trusts herein contained and upon such payment by the Company or any Paying Agent to the Trustee, the Company or such Paying Agent shall be released from all further liability with respect to such sums.

(d) Anything in this Section 3.05 to the contrary notwithstanding, the agreement to hold sums in trust as provided in this Section 3.05 is subject to Section 11.03 and Section 11.04.

Section 3.06. Existence. Subject to Article 12, the Company will do or cause to be done all things necessary to preserve and keep in full force and effect its corporate existence.

Section 3.07 . Stay, Extension and Usury Laws. The Company covenants (to the extent that it may lawfully do so) that it shall not at any time insist upon, plead, or in any manner whatsoever claim or take the benefit or advantage of, any stay, extension or usury law or other law which would prohibit or forgive the Company from paying all or any portion of the principal of, accrued and unpaid interest (including any Additional Interest) on, or any Extension Fee with respect to the Notes as contemplated herein, wherever enacted, now or at any time hereafter in force, or which may affect the covenants or the performance of this Indenture; and the Company (to the extent it may lawfully do so) hereby expressly waives all benefit or advantage of any such law, and covenants that it will not, by resort to any such law, hinder, delay or impede the execution of any power herein granted to the Trustee, but will suffer and permit the execution of every such power as though no such law had been enacted.

Section 3.08 . Compliance Certificate; Statements as to Defaults. The Company shall deliver to the Trustee within one hundred-twenty (120) calendar days after the end of each fiscal year of the Company (beginning with the fiscal

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year ending on December 30, 2007) an Officer’s Certificate stating whether or not the signer thereof has knowledge of any failure by the Company to comply with all conditions and covenants then required to be performed under this Indenture and, if so, specifying each such failure and the nature thereof.

In addition, the Company shall deliver to the Trustee, as soon as possible and in any event within thirty (30) days after the Company becomes aware of the occurrence of any Event of Default or Default, an Officer’s Certificate setting forth the details of such Event of Default or Default, its status and the action which the Company proposes to take with respect thereto.

Section 3.09 . Further Instruments and Acts. Upon request of the Trustee, the Company will execute and deliver such further instruments and do such further acts as may be reasonably necessary or proper to carry out more effectively the purposes of this Indenture.

ARTICLE 4

L ISTS OF N OTEHOLDERS AND R EPORTS BY THE C OMPANY AND THE T RUSTEE

Section 4.01 . Lists of Noteholders. The Company covenants and agrees that it will furnish or cause to be furnished to the Trustee, semi-annually, not more than fifteen (15) days after each February 1 and August 1 in each year beginning with February 1, 2008, and at such other times as the Trustee may request in writing, within thirty (30) days after receipt by the Company of any such request (or such lesser time as the Trustee may reasonably request in order to enable it to timely provide any notice to be provided by it hereunder), a list in such form as the Trustee may reasonably require of the names and addresses of the Noteholders as of a date not more than fifteen (15) days (or such other date as the Trustee may reasonably request in order to so provide any such notices) prior to the time such information is furnished, except that no such list need be furnished so long as the Trustee is acting as Note Registrar.

Section 4.02 . Preservation and Disclosure of Lists. (a) The Trustee shall preserve, in as current a form as is reasonably practicable, all information as to the names and addresses of the Noteholders contained in the most recent list furnished to it as provided in Section 4.01 or maintained by the Trustee in its capacity as Note Registrar, if so acting. The Trustee may destroy any list furnished to it as provided in Section 4.01 upon receipt of a new list so furnished.

(b) The rights of Noteholders to communicate with other Noteholders with respect to their rights under this Indenture or under such Notes and the corresponding rights and duties of the Trustee, shall be as provided by the Trust Indenture Act.

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(c) Every Noteholder, by receiving and holding the same, agrees with the Company and the Trustee that neither the Company nor the Trustee nor any agent of either of them shall be held accountable by reason of any disclosure of information as to names and addresses of Noteholders made pursuant to the Trust Indenture Act.

Section 4.03 . Reports by Trustee. (a) The Trustee shall transmit to Noteholders such reports concerning the Trustee and its actions under this Indenture as may be required pursuant to the Trust Indenture Act at the times and in the manner provided pursuant thereto. Reports so required to be transmitted at stated intervals of not more than 12 months shall be transmitted no later than March 1 in each calendar year, beginning with the year 2008. Each such report shall be dated as of a date not more than sixty (60) days prior to the date of transmission.

(b) A copy of such report shall, at the time of such transmission to Noteholders, be filed by the Trustee with each stock exchange and automated quotation system upon which the Notes are listed and with the Company. The Company will notify the Trustee in writing within a reasonable time when the Notes are listed on any stock exchange or automated quotation system and when any such listing is discontinued.

Section 4.04 . SEC Reports; Financial Statements.

(a) The Company shall file with the Trustee and the Commission, and transmit to Noteholders, such information, documents and other reports and such summaries thereof, as may be required pursuant to the Trust Indenture Act at the times and in the manner provided pursuant to such Act; provided that any such information, documents or reports required to be filed with the Commission pursuant to Section 13 or 15(d) of the Exchange Act shall be delivered to the Trustee within thirty (30 days) after the same is required to be filed with the Commission; provided , however , that the Company shall not be required to deliver to the Trustee any material for which the Company has sought and received confidential treatment by the Commission; provided further , each such report will be deemed to be so delivered to the Trustee if the Company files such report with the Commission through the Commission’s EDGAR system no later than the time such report is required to be filed with the Commission pursuant to the Exchange Act.

(b) In the event and for so long as the Company is not subject to Section 13 or 15(d) of the Exchange Act, it shall file with the Trustee and cause to be mailed to each holder at such holder’s registered address, upon the request of any holder or beneficial holder of the Notes or the Common Stock issued upon conversion thereof, and make available to such holder or beneficial holder of such Notes or Common Stock in connection with any sale thereof and any prospective

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purchaser of Notes or Common Stock designated by such holder or beneficial holder, the information required pursuant to Rule 144A(d)(4) under the Securities Act and it will take such further action as any holder or beneficial holder of such Notes or Common Stock may reasonably request, all to the extent required from time to time to enable such holder or beneficial holder to sell its Notes or Common Stock without registration under the Securities Act within the limitation of the exemption provided by Rule 144A, as such Rule may be amended from time to time.

(c) Delivery of such reports, information and documents 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 conclusively rely exclusively on an Officer’s Certificate).

ARTICLE 5

D EFAULTS AND R EMEDIES

Section 5.01 . Events of Default. The following events shall be “ Events of Default ” with respect to the Notes:

(a) default in any payment of interest (including any Additional Interest) on any Note when due and payable and the default continues for a period of thirty (30) days;

(b) default in the payment of principal of any Note when due and payable at the Maturity Date, upon required purchase, upon declaration or otherwise;

(c) failure by the Company to comply with its obligation to convert any Notes in accordance herewith, upon exercise of a holder’s conversion right;

(d) failure by the Company to comply with its obligations under Article 10;

(e) failure by the Company to issue a Designated Event Company Notice in accordance with Section 14.01(b) when due;

(f) failure by the Company for sixty (60) days to comply with any of its other agreements (other than a covenant or warranty or default in whose performance or whose breach is elsewhere in this Section specifically provided for) contained in the Notes or the Indenture after written notice of such default from the Trustee or the holders of at least twenty-five percent (25%) in principal amount of the Notes then outstanding has been received by the Company;

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(g) default by the Company or any majority-owned Subsidiary of the Company in the payment of the principal or interest on any mortgage, agreement or other instrument under which there may be outstanding, or by which there may be secured or evidenced, any debt for money borrowed in excess of $50,000,000 in the aggregate of the Company and/or any majority-owned Subsidiary, whether such debt now exists or shall hereafter be created, which default results in such debt becoming or being declared due and payable, and such acceleration shall not have been rescinded or annulled within sixty (60) days after written notice of such acceleration has been received by the Company or such majority-owned Subsidiary;

(h) any judgment or judgments for the payment of money in an aggregate amount in excess of $50,000,000 (or its foreign currency equivalent at the time) that shall be rendered against the Company or any majority-owned Subsidiary of the Company and that shall not be waived, satisfied or discharged for any period of sixty (60) consecutive days during which a stay of enforcement shall not be in effect;

(i) the Company or any of its Significant Subsidiaries shall commence a voluntary case or other proceeding seeking liquidation, reorganization or other relief with respect to the Company or any of its Significant Subsidiaries or its debts under any bankruptcy, insolvency or other similar law now or hereafter in effect or seeking the appointment of a trustee, receiver, liquidator, custodian or other similar official of the Company or any of its Significant Subsidiaries or any substantial part of its property, or shall consent to any such relief or to the appointment of or taking possession by any such official in an involuntary case or other proceeding commenced against it, or shall make a general assignment for the benefit of creditors, or shall fail generally to pay its debts as they become due; or

(j) an involuntary case or other proceeding shall be commenced against the Company or any of its Significant Subsidiaries seeking liquidation, reorganization or other relief with respect to the Company, any of its Significant Subsidiaries or such entity’s debts under any bankruptcy, insolvency or other similar law now or hereafter in effect or seeking the appointment of a trustee, receiver, liquidator, custodian or other similar official of the Company or any of its Significant Subsidiaries or any substantial part of its property, and such involuntary case or other proceeding shall remain undismissed and unstayed for a period of ninety (90) consecutive days.

In case one or more Events of Default shall have occurred and be continuing (whatever the reason for such Event of Default and whether it shall be voluntary or involuntary or be 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), then, and in each and every such case

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(other than an Event of Default specified in Section 5.01(i) or Section 5.01(j)), unless the principal of all of the Notes shall have already become due and payable, either the Trustee or the holders of at least twenty-five percent (25%) in aggregate principal amount of the Notes then outstanding determined in accordance with Section 7.04, by notice in writing to the Company (and to the Trustee if given by Noteholders), may declare one hundred percent (100%) of the principal of, and accrued and unpaid interest, Additional Interest, if any, on, all the Notes 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 Notes contained to the contrary notwithstanding. If an Event of Default specified in Section 5.01(i) or Section 5.01(j) occurs and is continuing, the principal of all the Notes and accrued and unpaid interest, Additional Interest, if any, shall be immediately due and payable. This provision, however, is subject to the conditions that if, at any time after the principal of the Notes shall have been so declared due and payable, and before any judgment or decree for the payment of the monies due shall have been obtained or entered as hereinafter provided, the Company shall pay or shall deposit with the Trustee a sum sufficient to pay installments of accrued and unpaid interest and Additional Interest, if any, upon all Notes and the principal of any and all Notes that shall have become due other than by acceleration (with interest on overdue installments of accrued and unpaid interest and Additional Interest, if any (to the extent that payment of such interest is enforceable under applicable law) on such principal at the rate borne by the Notes during the period of such Default) and amounts due to the Trustee pursuant to Section 6.06, and if (1) rescission would not conflict with any judgment or decree of a court of competent jurisdiction and (2) any and all Events of Defaults under this Indenture, other than the nonpayment of principal of and accrued and unpaid interest and Additional Interest, if any, on Notes that shall have become due solely by such acceleration, shall have been cured or waived pursuant to Section 5.07, then and in every such case the holders of a majority in aggregate principal amount of the Notes then outstanding, by written notice to the Company and to the Trustee, may waive all Defaults or Events of Default with respect to the Notes and rescind and annul such declaration and its consequences and such Default shall cease to exist, and any Event of Default arising therefrom shall be deemed to have been cured for every purpose of this Indenture; but no such waiver or rescission and annulment shall extend to or shall affect any subsequent default or Event of Default, or shall impair any right consequent thereon. The Company shall notify the Responsible Officer of the Trustee in writing, promptly upon becoming aware thereof, of any Event of Default by delivering to the Trustee a statement specifying such Event of Default and any action the Company has taken, is taking or proposes to take with respect thereto.

Notwithstanding the foregoing, if so elected by the Company, the sole remedy for an Event of Default relating to the failure to comply with Section 4.04(a) hereof or Section 314(a)(1) of the Trust Indenture Act, will for the first

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sixty (60) days after the occurrence of such an Event of Default consist exclusively of the right to receive a one-time additional payment (the “ Extension Fee ”) on the Notes in an amount equal to 0.25% of the principal amount of the Notes. The Extension Fee will be in addition to any Additional Interest that may accrue pursuant to Section 3.08. On the sixty-first (61st) day after such Event of Default (if the Event of Default relating to the reporting obligations is not cured or waived prior to such sixty-first (61st) day), the Notes will be subject to acceleration as provided above. The foregoing provisions in this Section 5.01 will not affect the rights of Noteholders in the event of the occurrence of any other Event of Default. In the event the Company does not elect to pay the Extension Fee upon an Event of Default in accordance with this paragraph, the Notes will be subject to acceleration as provided above.

In order to elect to pay the Extension Fee as the sole remedy during the first sixty (60) days after the occurrence of an Event of Default relating to the failure to comply with the reporting obligations in accordance with the immediately preceding paragraph, the Company must (i) notify all Noteholders and the Trustee and Paying Agent of such election and pay such Extension Fee on or before the close of business on the date on which such Event of Default occurs and (ii) pay such Extension Fee on or before the close of business on the date on which such Event of Default occurs. The Extension Fee shall be payable to Noteholders of record on the date of such notice. Upon the Company’s failure to timely give such holders such notice or pay such Extension Fee, the Notes will be subject to acceleration as provided above.

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

Section 5.02 . Payments of Notes on Default; Suit Therefor. In the event that the Trustee or the holders of not less than twenty-five percent (25%) in aggregate principal amount of the Notes then outstanding hereunder have declared the principal of, and accrued and unpaid interest (including any Additional Interest) on, the Notes, to be due and payable immediately in accordance with Section 5.01, and the Company shall have failed forthwith to pay such amounts, the Trustee, in its own name and as trustee of an express trust, after being furnished suitable indemnity pursuant to Section 6.01, shall be entitled and empowered to institute any actions or proceedings at law or in equity for the collection of the sums so due and unpaid (including such further amounts as shall be sufficient to cover the reasonable costs and expenses of collection, including

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reasonable compensation to the Trustee, its agents, attorneys and counsel, and any expenses or liabilities incurred by the Trustee hereunder other than through its negligence or bad faith), and may prosecute any such action or proceeding to judgment or final degree, and may enforce any such judgment or final decree against the Company or any other obligor on the Notes and collect in the manner provided by law out of the property of the Company or any other obligor on the Notes wherever situated the monies 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 on the Notes under Title 11 of the United States Code, or any other applicable law, or in case a receiver, assignee or trustee in bankruptcy or reorganization, liquidator, sequestrator or similar official shall have been appointed for or taken possession of the Company or such other obligor, the property of the Company or such other obligor, or in the case of any other judicial proceedings relative to the Company or such other obligor upon the Notes, or to the creditors or property of the Company or such other obligor, the Trustee, irrespective of whether the principal of the Notes 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 5.02, 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 and accrued and unpaid interest (including any Additional Interest) in respect of the Notes, and, in case of any judicial proceedings, to file such proofs of claim and other papers or documents and to take such other actions as it may deem necessary or advisable in order to have the claims of the Trustee (including any claim for the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel) and of the Noteholders allowed in such judicial proceedings relative to the Company or any other obligor on the Notes, its or their creditors, or its or their property, and to collect and receive any monies or other property payable or deliverable on any such claims, and to distribute the same after the deduction of any amounts due the Trustee under Section 6.06; and any receiver, assignee or trustee in bankruptcy or reorganization, liquidator, custodian or similar official is hereby authorized by each of the Noteholders to make such payments to the Trustee, as administrative expenses, and, in the event that the Trustee shall consent to the making of such payments directly to the Noteholders, to pay to the Trustee any amount due it for reasonable compensation, expenses, advances and disbursements, including agents and counsel fees, and including any other amounts due to the Trustee under Section 6.06 hereof, incurred by it up to the date of such distribution. To the extent that such payment of reasonable compensation, expenses, advances and disbursements out of the estate in any such proceedings shall be denied for any reason, payment of the same shall be secured by a lien on, and shall be paid out of, any and all distributions, dividends, monies, securities and other property which the holders of the Notes may be entitled to receive in such proceedings, whether in liquidation or under any plan of reorganization or arrangement or otherwise.

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

All rights of action and of asserting claims under this Indenture, or under any of the Notes, may be enforced by the Trustee without the possession of any of the Notes, or the production thereof at any trial or other proceeding relative thereto, and any such suit or proceeding instituted by the Trustee shall be brought in its own name as trustee of an express trust, and any recovery of judgment shall, after provision for the payment of the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel, be for the ratable benefit of the holders of the Notes.

In any proceedings brought by the Trustee (and in any proceedings involving the interpretation of any provision of this Indenture to which the Trustee shall be a party) the Trustee shall be held to represent all the holders of the Notes, and it shall not be necessary to make any holders of the Notes parties to any such proceedings.

Section 5.03 . Application of Monies Collected by Trustee. Any monies collected by the Trustee pursuant to this Article 5 with respect to the Notes shall be applied in the order following, at the date or dates fixed by the Trustee for the distribution of such monies, upon presentation of the several Notes, and stamping thereon the payment, if only partially paid, and upon surrender thereof, if fully paid:

First, to the payment of all amounts due the Trustee under Section 6.06;

Second, in case the principal of the outstanding Notes shall not have become due and be unpaid, to the payment of interest (including any Additional Interest) on the Notes in default 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 borne by the Notes, such payments to be made ratably to the Persons entitled thereto;

Third, in case the principal of the outstanding Notes shall have become due, by declaration or otherwise, and be unpaid to the payment of the whole amount (including, if applicable, payments in respect of the Conversion Obligation and Additional Shares) then owing and unpaid upon the Notes for principal and interest (including any Additional Interest), with interest on the

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overdue principal (to the extent that such interest has been collected by the Trustee) upon overdue installments of interest at the rate borne by the Notes, and in case such monies shall be insufficient to pay in full the whole amounts so due and unpaid upon the Notes, then to the payment of such principal and interest (including any Additional Interest) without preference or priority of principal over interest, or of interest over principal or of any installment of interest over any other installment of interest, or of any Note over any other Note, ratably to the aggregate of such principal and accrued and unpaid interest; and

Fourth, to the payment of the remainder, if any, to the Company or any other Person lawfully entitled thereto.

Section 5.04 . Proceedings by Noteholders. No holder of any Note shall have any right by virtue of or by availing of any provision of this Indenture to institute any suit, action or proceeding in equity or at law upon or under or with respect to this Indenture, or for the appointment of a receiver, trustee, liquidator, custodian or other similar official, or for any other remedy hereunder, unless such holder previously shall have given to the Trustee written notice of an Event of Default and of the continuance thereof, as hereinbefore provided, and unless also the holders of not less than twenty-five percent (25%) in aggregate principal amount of the Notes then outstanding shall have made written request upon the Trustee to institute such action, suit or proceeding in its own name as Trustee hereunder and shall have offered to the Trustee such security or indemnity reasonably satisfactory to it against any loss, liability or expense to be incurred therein or thereby, and the Trustee for sixty (60) days after its receipt of such notice, request and offer of indemnity, shall have neglected or refused to institute any such action, suit or proceeding and no direction that, in the opinion of the Trustee, is inconsistent with such written request shall have been given to the Trustee by the holders of a majority in principal amount of the Notes outstanding pursuant to Section 5.07; it being understood and intended, and being expressly covenanted by the holder of every Note with every other holder and the Trustee, that no one or more Noteholders shall have any right in any manner whatever by virtue of or by availing of any provision of this Indenture to affect, disturb or prejudice the rights of any other Noteholder, 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 Noteholders (except as otherwise provided herein). For the protection and enforcement of this Section 5.04, each and every Noteholder and the Trustee shall be entitled to such relief as can be given either at law or in equity.

Notwithstanding any other provision of this Indenture and any provision of any Note, the right of any Noteholder to receive payment of the principal of and accrued and unpaid interest (including any Additional Interest) on such Note, on or after the respective due dates expressed in such Note, or to institute suit for the enforcement of any such payment on or after such respective dates against the Company shall not be impaired or affected without the consent of such Noteholder.

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Anything in this Indenture or the Notes to the contrary notwithstanding, the holder of any Note, without the consent of either the Trustee or the holder of any other Note, in his own behalf and for his own benefit, may enforce, and may institute and maintain any proceeding suitable to enforce, his rights of conversion as provided herein.

Section 5.05 . Proceedings by Trustee. In case of an Event of Default 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 are necessary to protect and enforce any of such rights, either by suit in equity or by action at law or by proceeding 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.

Section 5.06 . Remedies Cumulative and Continuing. Except as provided in the last paragraph of Section 2.08, all powers and remedies given by this Article 5 to the Trustee or to the Noteholders 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 of the Notes, 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 of any of the Notes to exercise any right or power accruing upon any default or Event of Default shall impair any such right or power, or shall be construed to be a waiver of any such default or any acquiescence therein; and, subject to the provisions of Section 5.04, every power and remedy given by this Article 5 or by law to the Trustee or to the Noteholders may be exercised from time to time, and as often as shall be deemed expedient by the Trustee or by the Noteholders.

Section 5.07 . Direction of Proceedings and Waiver of Defaults by Majority of Noteholders. The holders of a majority in aggregate principal amount of the Notes at the time outstanding determined in accordance with Section 7.04 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 Notes; provided , however , that (a) such direction shall not be in conflict with any rule of law or with this Indenture, and (b) the Trustee may take any other action deemed proper by the Trustee that is not inconsistent with such direction. The Trustee may refuse to follow any direction that it determines is unduly prejudicial to the rights of any other holder or that would involve the Trustee in personal liability. The holders of a majority in aggregate principal amount of the N