Indenture dated as of August 6, 2003

Reconciliation and Tie Between the Trust Indenture Act of 1939 and Indenture, dated as of August 6, 2003, between Mentor Graphics Corporation and Wilmington Trust Company, as Trustee.

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

This INDENTURE, dated as of August 6, 2003, is between Mentor Graphics Corporation, an Oregon corporation (hereinafter called the “Company”), having its principal office at 8005 SW Boeckman Road, Wilsonville, Oregon 97070-7777, and Wilmington Trust Company, a Delaware banking corporation, as trustee hereunder (hereinafter called the “Trustee”), having its principal corporate office at 1100 North Market Street, Rodney Square North, Wilmington, Delaware 19890-0001.

WHEREAS, for its lawful corporate purposes, the Company has duly authorized the issue of its Floating Rate Convertible Subordinated Debentures due 2023 (hereinafter called the “Debentures”), in an aggregate principal amount not to exceed $100,000,000 (or $110,000,000 if the option set forth in Section 2 of the Purchase Agreement dated as of July 31, 2003 (as amended from time to time by the parties thereto) by and between the Company and the Initial Purchasers is exercised in full) and, to provide the terms and conditions upon which the Debentures are to be authenticated, issued and delivered, the Company has duly authorized the execution and delivery of this Indenture; and

WHEREAS, the Debentures, the certificate of authentication to be borne by the Debentures, a form of assignment, a form of option to elect repayment upon a Change of Control, and a form of conversion notice to be borne by the Debentures are to be substantially in the forms hereinafter provided for; and

WHEREAS, all acts and things necessary to make the Debentures, when executed by the Company and authenticated and delivered by the Trustee or a duly authorized authenticating agent, as provided in this Indenture, 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 and the issue hereunder of the Debentures have in all respects been duly authorized.

That in order to declare the terms and conditions upon which the Debentures are, and are to be, authenticated, issued and delivered, and in consideration of the premises and of the purchase and acceptance of the Debentures 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 Debentures (except as otherwise provided below), as follows:

Section 1.01 Definitions. 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 that 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. 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.

“Accreted Interest” means, for any Interest Period for the Debenture as of any date of determination, (i) the Accreted Principal Amount of such Debenture at the beginning of the Interest Period in which such date occurs, multiplied by (ii) the 3-Month Libor for such Interest Period, multiplied by (iii) the quotient of the actual number of days elapsed from and including the first day of such Interest Period, to but excluding the date of determination divided by 360; provided that the Accreted Interest for any full Interest Period shall be calculated by reference to the actual number of days in such Interest Period divided by 360.

“Accreted Principal Amount” means as of any date of determination, (i) the Original Principal Amount of the Debentures, plus (ii) the sum of the Accreted Interest for each Interest Period concluding on or prior to such date, plus (iii) the Accreted Interest for the Interest Period in which such date occurs as of the date of determination.

“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.

“Business Day” means each Monday, Tuesday, Wednesday, Thursday and Friday which is neither a legal holiday nor a day on which commercial banks are authorized or required by law, regulation or executive order to close in The City of New York, provided that day is also a London Banking Day.

“Calculation Agent” means Wilmington Trust Company, as Calculation Agent with respect to the Debentures, or any successor entity thereto.

“Change of Control” means the occurrence of any of the following after the original issuance of the Debentures: (a) the acquisition by any Person, of beneficial ownership, directly or indirectly, through a purchase, merger or other acquisition transaction or series of purchase, merger or other acquisition transactions, of shares of the Company’s capital stock entitling that Person to exercise 50% or more of the total voting power of all shares of Company’s capital stock entitled to vote generally in elections of directors, other than any acquisition by the Company, any of the Company’s subsidiaries or any of the Company’s employee benefit plans, (b) the first day on which a majority of the members of the Board of Directors of the Company are not Continuing Directors; or (c) the Company’s consolidation or merger with or into any

other Person, any merger of another Person into the Company, or any conveyance, transfer, sale, lease or other disposition of all or substantially all of the Company’s properties and assets to another Person, other than (i) any transaction pursuant to which holders of the Company’s capital stock immediately prior to the transaction have the entitlement to exercise, directly or indirectly, 50% or more of the total voting power of all shares of capital stock entitled to vote generally in elections of directors of the continuing or surviving Person immediately after giving effect to such transaction; and (ii) any merger, share exchange, transfer of assets or similar transaction solely for the purpose of changing the Company’s jurisdiction of incorporation and resulting in a reclassification, conversion or exchange of outstanding shares of Common Stock, if at all, solely into shares of common stock, ordinary shares or American Depositary Shares of the surviving entity or a direct or indirect parent of the surviving corporation; provided that a Change of Control shall not be deemed to have occurred if either (x) the Closing Price of the Common Stock for any five (5) Trading Days during the ten (10) Trading Days immediately preceding the Change of Control is equal to at least 105% of the Conversion Price in effect on the date on which the Change of Control occurs or (y) in the case of a merger or consolidation otherwise constituting a Change of Control, all of the consideration (excluding cash payments for fractional shares) in such merger or consolidation constituting the Change of Control consists of common stock traded on a United States national securities exchange or quoted on the Nasdaq National Market (or which will be so traded or quoted when issued or exchanged in connection with such Change of Control) and as a result of such transaction or transactions the Debentures become convertible solely into such common stock. Beneficial ownership shall be determined in accordance with Rule 13d-3 promulgated by the Commission under the Exchange Act. The term “Person” as used in this definition includes any syndicate or group that would be deemed to be a “person” under Section 13(d)(3) of the Exchange Act.

“Commission” means the Securities and Exchange Commission, as from time to time constituted, created under the Exchange Act, or, if at any time after the execution of this Indenture such Commission is not existing and performing the duties now assigned to it under the Trust Indenture Act, then the body performing such duties at such time.

“Common Stock” means any stock of any class of the Company which has 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 which is not subject to redemption by the Company. Subject to the provisions of Section 15.06, however, shares issuable on conversion of Debentures shall include only shares of the class designated as common stock of the Company at the date of this Indenture (namely, the Common Stock, no par value) or shares of any class or classes resulting from any reclassification or reclassifications thereof and which 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 which are not subject to redemption by the Company; provided, however, 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 the corporation named as the “Company” in the first paragraph of this Indenture, and, subject to the provisions of Article 12, shall include its successors and assigns.

“Continuing Director” means, at any date, a member of the Company’s Board of Directors (i) who was a member of such board on August 6, 2003 or (ii) who was nominated or elected by at least a majority of the directors who were Continuing Directors at the time of such nomination or election or whose election to the Company’s Board of Directors was recommended or endorsed by at least a majority of the directors who were Continuing Directors at the time of such nomination or election or such lesser number comprising a majority of a nominating committee comprised of independent directors if authority for such nominations or elections has been delegated to a nominating committee whose authority and composition have been approved by at least a majority of the directors who were Continuing Directors at the time such committee was formed. (Under this definition, if the Board of Directors of the Company as of the date of this Indenture were to approve a new director or directors and then resign, no Change of Control would occur even though the current Board of Directors would thereafter cease to be in office).

“Conversion Price” shall equal (i) $1,000 divided by the (ii) the Conversion Rate.

“Corporate Trust Office” or other similar term, means the designated office of the Trustee at which at any particular time its corporate trust business shall be administered, which office is, at the date as of which this Indenture is dated, located at c/o Computershare Trust Company of New York, Wall Street Plaza, 88 Pine Street, 19th floor, New York, NY 10005 Attn: Wilmington Trust (Mentor Graphics Corporation, Floating Rate Convertible Subordinated Debentures due 2023).

“Credit Agreement” means that certain Credit Agreement dated as of July 14, 2003 among the Company, Bank of America, N.A., as Agent, Key Corporate Capital, Inc., as Documentation Agent, Fleet National Bank, as Syndication Agent and the other financial institutions from time to time parties thereto (including all deferrals, renewals, extensions, refundings, refinancings or replacements of, or amendments, modifications or supplements to, the foregoing).

“Custodian” means Wilmington Trust Company, as custodian with respect to the Debentures in global form, or any successor entity thereto.

“Debenture” or “Debentures” means any Debenture or Debentures, as the case may be, authenticated and delivered under this Indenture, including the Global Debenture.

“Debentureholders” or “holder” as applied to any Debenture, or other similar terms (but excluding the term “beneficial holder”), means any Person in whose name at the time a particular Debenture is registered on the Debenture registrar’s books.

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

“Depositary” means, with respect to the Debentures issuable or issued in whole or in part in global form, the Person specified in Section 2.05(d) as the Depositary with respect to such Debentures, 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 Senior Debt” means any Indebtedness from time to time outstanding under the Credit Agreement and the Company’s obligations under any other particular Senior Debt in which the instrument creating or evidencing the same or the assumption or guarantee thereof (or related agreements or documents to which the Company is a party) expressly provides that such Senior Debt shall be “Designated Senior Debt” for purposes of this Indenture or that the Company designates in writing to the Trustee as “Designated Senior Debt” for purposes of this Indenture (provided that such instrument, agreement or other document may place limitations and conditions on the right of such Senior Debt to exercise the rights of Designated Senior Debt). If any payment made to any holder of any Designated Senior Debt or its Representative with respect to such Designated Senior Debt is rescinded or must otherwise be returned by such holder or Representative upon the insolvency, bankruptcy or reorganization of the Company or otherwise, the reinstated Indebtedness of the Company arising as a result of such rescission or return shall constitute Designated Senior Debt effective as of the date of such rescission or return.

“Designated Subsidiary” means any existing or future, direct or indirect, Subsidiary of the Company whose assets constitute 15% or more of the total assets of the Company on a consolidated basis.

“Event of Default” means any event specified in Section 7.01(a), (b), (c), (d), (e) or (f).

“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder, as in effect from time to time.

“Exchange Rate Contract” means, with respect to any Person, any currency swap agreements, forward exchange rate agreements, foreign currency futures or options, exchange rate collar agreements, exchange rate insurance and other agreements or arrangements, or combination thereof, the principal purpose of which is to provide protection against fluctuations in currency exchange rates. An Exchange Rate Contract may also include an Interest Rate Agreement.

“GAAP” means generally accepted accounting principles set forth in the opinions and pronouncements of the Accounting Principles Board of the American Institute of Certified Public Accountants and statements and pronouncements of the Financial Accounting Standards Board or in such other statements by such other entity as approved by a significant segment of the accounting profession, which are applied on a consistent basis.

“Guarantee” means a guarantee, other than by endorsement of negotiable instruments for collection in the ordinary course of business, direct or indirect, in any manner, including, without limitation, letters of credit and reimbursement agreements in respect thereof, of all or any part of any Indebtedness.

“Indebtedness” means, with respect to any Person, any indebtedness of such Person, whether or not contingent, in respect of borrowed money or evidenced by bonds, notes, Debentures or similar instruments or letters of credit, bank guarantees or bankers’ acceptances, or reimbursement agreements in respect thereof, or representing the balance deferred and unpaid of the purchase price of any property, including pursuant to capital leases and sale-and-leaseback transactions, or representing the Company’s obligations and liabilities, contingent or otherwise, in respect of leases required, in conformity with GAAP, to be accounted for as capitalized lease obligations on the Company’s balance sheet, or under other leases for facilities, equipment or related assets, whether or not capitalized, entered into or leased for financing purposes, or representing any hedging obligations under an Exchange Rate Contract or an Interest Rate Agreement, except any such balance that constitutes an accrued expense or trade payable, if and to the extent any of the foregoing indebtedness, other than obligations under an Exchange Rate Contract or an Interest Rate Agreement, would appear as a liability upon a balance sheet of such Person prepared in accordance with GAAP, and also includes, to the extent not otherwise included, the Guarantee of items which would be included within this definition. The amount of any Indebtedness outstanding as of any date shall be the accreted value thereof, in the case of any Indebtedness issued with original issue discount. Indebtedness shall not include liabilities for taxes of any kind.

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

“Interest Payment Date” means February 6, May 6, August 6 and November 6 of each year, commencing November 6, 2003 until (subject to Article 3 hereof) August 6, 2023; provided, however, that, except for an interest Payment Date coinciding with the Maturity Date or earlier Redemption Date or Repurchase Date), if any Interest Payment Date would is a day that is not a Business Day, that Interest Payment Date will be postponed to the next succeeding Business Day, provided that, if that Business Day falls in the next succeeding calendar month, that Interest Payment Date will be the immediately preceding Business Day.

“Interest Period” means the period of days beginning with a Interest Payment Date and ending on the day prior to next succeeding Interest Payment Date.

“Initial Purchasers” means Merrill, Lynch, Pierce, Fenner & Smith Incorporated, Bank of American Securities LLC, Fleet Securities, Inc., McDonald Investments Inc., a KeyCorp company, Adam, Harkness & Hill, Inc., D.A. Davidson & Co., Needham & Company, Inc. and Wells Fargo Securities, LLC.

“Institutional Accredited Investor” means an institutional “accredited investor” within the meaning of Rule 501(a)(l), (2), (3) or (7) under the Securities Act.

“Interest Rate Agreement” means, with respect to any Person, any interest rate swap agreement, interest rate cap agreement, interest rate collar agreement or other similar agreement the principal purpose of which is to protect the party indicated therein against fluctuations in interest rates.

“Liquidated Damages” has the meaning specified in Section 3(a) of the Registration Rights Agreement.

“London Banking Day” means a day on which commercial banks are open for business, including dealings in United States dollars, in London.

“Moneyline Telerate Page 3750” means the display on Moneyline Telerate (or any successor service) on such page (or any other page as may replace such page on such service) for the purpose of displaying the London interbank rates of major banks for United States dollars.

“Officers’ Certificate,” when used with respect to the Company, means a certificate signed by both (a) the Chairman of the Board, the Chief Executive Officer, the President or any vice President (whether or not designated by a number or numbers or word or words added before or after the title “Vice President”) and (b) the Treasurer or any Assistant Treasurer, the Controller or any Assistant Controller, or the Secretary or any Assistant Secretary of the Company.

“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 reasonably acceptable to the Trustee.

“Original Principal Amount” of a Debenture means the stated original principal amount as set forth on the face of such Debenture.

“outstanding,” when used with reference to Debentures and subject to the provisions of Section 9.04, means, as of any particular time, all Debentures authenticated and delivered by the Trustee under this Indenture, except:

“Payment Blockage Notice” has the meaning specified in Section 4.02(ii).

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

“Portal Market” means The Portal Market operated by the National Association of Securities Dealers, Inc. or any successor thereto.

“Predecessor Debenture” of any particular Debenture means every previous Debenture evidencing all or a portion of the same debt as that evidenced by such particular Debenture, and, for the purposes of this definition, any Debenture authenticated and delivered under Section 2.06 in lieu of a lost, destroyed or stolen Debenture shall be deemed to evidence the same debt as the lost, destroyed or stolen Debenture that it replaces.

“QIB” means a “qualified institutional buyer” as defined in Rule 144A.

“Rate/ Yield Determination Late” means the second London Banking Day preceding the related Reset Date.

“Registration Rights Agreement” means that certain Registration Rights Agreement, dated as of August 6, 2003, among the Company and the Initial Purchasers, as amended from time to time in accordance with its terms.

“Representative” means (a) the indenture trustee or other trustee, agent or representative for holders of Senior Debt or (b) with respect to any Senior Debt that does not have any such trustee, agent or other representative, (i) in the case of such Senior Debt issued pursuant to an agreement providing for voting arrangements as among the holders or owners of such Senior Debt, any holder or owner of such Senior Debt acting with the consent of the required persons necessary to bind such holders or owners of such Senior Debt and (ii) in the case of all other such Senior Debt, the holder or owner of such Senior Debt.

“Reset Date” means each February 6, May 6, August 6 and November 6 of each year, commencing November 6, 2003; provided, however, that if any Reset Date would otherwise be a day that is not a Business Day, that Reset Date will be postponed to the next succeeding Business Day, except if that Business Day falls in the next succeeding calendar month, that Reset Date will be the immediately preceding Business Day.

“Responsible Officer”, when used with respect to the Trustee, means an officer of the Trustee in the Corporate Trust Office assigned and duly authorized by the Trustee to administer this Indenture.

“Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder, as in effect from time to time.

“Senior Debt” means Indebtedness (including any monetary obligation in respect of the Credit Agreement (including, without limitation, any such obligations thereunder relating to fees, costs and expenses incurred after the filing of a petition initiating any proceeding under any bankruptcy, insolvency or similar law), and interest, whether or not allowable, accruing on Indebtedness incurred pursuant to the Credit Agreement after the filing of a petition initiating any proceeding under any bankruptcy, insolvency or similar law) of the Company arising under the Credit Agreement or any other Indebtedness of the Company, whether outstanding on the date of this Indenture or thereafter created, incurred, assumed or guaranteed by the Company. Notwithstanding anything to the contrary in the foregoing, Senior Debt shall not include: (a) Indebtedness of or amounts owed by the Company for compensation to employees, or for goods or materials purchased or for services obtained in the ordinary course of business; (b) Indebtedness of the Company to any subsidiary of the Company; (c) Indebtedness of the Company that expressly provides that it shall not be senior in right of payment to the Debentures or expressly provides that it is pari passu with or junior to the Debentures; or (d) any Indebtedness under the Company’s existing 6⁷/8% Convertible Subordinated Notes Due 2007 (with which these Debentures will rank pari passu).

“Subsidiary” means, with respect to any Person, (i) any corporation, association or other business entity of which more than 50% of the total voting power of shares of capital stock or other equity interest entitled (without regard to the occurrence of any contingency) to vote in the election of directors, managers or trustees thereof is at the time owned or controlled, directly or indirectly, by such Person or one or more of the other subsidiaries of that Person (or a combination thereof) and (ii) any partnership (a) the sole general partner or managing general partner of which is such Person or a subsidiary of such Person or (b) the only general partners of which are such Person or of one or more subsidiaries of such Person (or any combination thereof).

(a) the blended rate for three-month deposits in United States dollars commencing on such Reset Date, that appears on the Moneyline Telerate Page 3750 as of 11:00 a.m., London time, on the related Rate/Yield Determination Date;

(b) if fewer than two source rates are used to calculate the blended rate, or if no rate appears on the particular Rate/Yield Determination Date on the Moneyline Telerate Page 3750, the rate calculated by the Calculation Agent as the arithmetic mean of at least two offered quotations obtained by the Calculation Agent after requesting the principal London offices of

each of four major reference banks (which shall not include Affiliates of the Calculation Agent) in the London interbank market to provide the Calculation Agent with its offered quotation for deposits in United States dollars for the period of three months, commencing on the related Reset Date, to prime banks in the London interbank market at approximately 11:00 a.m., London time, on that Rate/Yield Determination Date and in a principal amount that is representative for a single transaction in United States dollars in that market at that time; or

(c) if fewer than two offered quotations referred to in clause (b) are provided as requested, the rate calculated by the Calculation Agent as the arithmetic mean of the rates quoted at approximately 11:00 a.m., New York time, on the particular Rate/Yield Determination Date by three major banks (which shall not include Affiliates of the Calculation Agent) in The City of New York selected by the Calculation Agent for loans in United States dollars to leading European banks for a period of three months and in a principal amount that is representative for a single transaction in United States dollars in that market at that time; or

(d) if the banks so selected by the Calculation Agent are not quoting as mentioned in clause (c), the current 3-month LIBOR in effect from the immediately preceding Rate/Yield Determination Date.

For purposes of clauses (b) and (c) above, all percentages resulting from such calculations will be rounded, if necessary, to the nearest one hundred-thousandth of a percentage point, with five one-millionths of a percertange point rounded upwards.

“Trust Indenture Act” means the Trust Indenture Act of 1939, as amended.

“Trustee” means Wilmington Trust Company 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.

The definitions of certain other terms are as specified in Sections 2.05, 3.05 and 3.06 and Article 15.

Section 2.01 Designation Amount and Issue of Debentures. The Debentures shall be designated as “Floating Rate Convertible Subordinated Debentures due 2023,” not to exceed the aggregate principal amount of $100,000,000 (or $110,000,000 if the option set forth in Section 2 of the Purchase Agreement dated as of July 31, 2003 by and between the Company and the Initial Purchasers is exercised in full) (except pursuant to Sections 2.05, 2.06, 3.03, 3.05, 3.06 and 15.02 hereof or as otherwise expressly permitted herein) upon the execution of this Indenture, or from time to time thereafter, may be executed by the Company and delivered to the Trustee for authentication,. and the Trustee shall thereupon authenticate and deliver said

Debentures to or upon the written order of the Company, signed by (a) its Chairman of the Board, Chief Executive Officer, President or any Vice President (whether or not designated by a number or numbers or word or words added before or after the title “Vice President”) and (b) its Treasurer or any Assistant Treasurer, its Controller or any Assistant Controller or its Secretary or any Assistant Secretary, without any further action by the Company hereunder.

Section 2.02 Form of Debentures. The Debentures and the Trustee’s certificate of authentication to be borne by such Debentures shall be substantially in the form set forth in Exhibit A, which is incorporated in and made a part of this Indenture.

Any of the Debentures may have such letters, numbers or other marks of identification and such notations, legends and 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 Debentures may be listed, or to conform to usage.

Any Debenture in global form shall represent such of the outstanding Debentures as shall be specified therein and shall provide that it shall represent the aggregate amount of outstanding Debentures from time to time endorsed thereon and that the aggregate amount of outstanding Debentures represented thereby may from time to time be increased or reduced to reflect transfers or exchanges permitted hereby. Any endorsement of a Debenture in global form to reflect the amount of any increase or decrease in the amount of outstanding Debentures 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 Debentures in accordance with this Indenture. Payment of principal of and interest and premium, if any, on any Debenture in global form shall be made to the holder of such Debenture.

The terms and provisions contained in the form of Debenture attached as Exhibit A hereto 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 Date and Denomination of Debentures; Payments of Interest. The Debentures shall be issuable in registered form without coupons in denominations of $1,000 principal amount and integral multiples thereof. Every Debenture shall be dated the date of its authentication and shall bear interest from the applicable date in each case as specified on the face of the form of Debenture attached as Exhibit A hereto. Interest on the Debentures shall be computed using the actual number of days elapsed between the Reset Dates divided by 360.

The Person in whose name any Debenture (or its Predecessor Debenture) is registered on the Debenture register at the close of business on any record date with respect to any Interest Payment Date shall be entitled to receive the interest payable on such Interest Payment Date, except (i) that the interest payable upon redemption (unless the date of redemption is an Interest Payment Date) will be payable to the Person to whom principal is payable and (ii) as set forth in the next succeeding sentence. In the case of any Debenture (or portion thereof) that is converted into Common Stock during the period from (but excluding) a record date to (but excluding) the

next succeeding Interest Payment Date, either (x) if such Debenture (or portion thereof) has been called for redemption on a redemption date which occurs during such period, or is to be redeemed in connection with a Change of Control on a Repurchase Date (as defined in Section 3.06) that occurs during such period, the Company shall be required to pay interest on such Interest Payment Date in respect of any such Debenture (or portion thereof) or (y) if such Debenture (or portion thereof) has not been called for redemption on a redemption date that occurs during such period and is not to be redeemed in connection with a Change of Control on a Repurchase Date that occurs during such period, such Debenture (or portion thereof) that is submitted for conversion during such period shall be accompanied by funds equal to the interest payable on such succeeding Interest Payment Date on the principal amount so converted, as provided in the penultimate paragraph of Section 15.02 hereof. Interest shall be payable at the office of the Company maintained by the Company for such purposes in the Borough of Manhattan, The City of New York, which shall initially be an office or agency of the Trustee and may, as the Company shall specify to the paying agent in writing by each record date, be paid either by check mailed to the address of the Person entitled thereto as it appears in the Debenture register (provided that the holder of Debentures with an aggregate principal amount in excess of $5,000,000 shall, at the written election of such holder, be paid by wire transfer in immediately available funds); provided, however, that payments to the Depositary will be made by wire transfer of immediately available funds to the account of the Depositary or its nominee. The term “record date” with respect to any Interest Payment Date shall mean the January 21, April 21, July 21 or October 21 preceding the relevant February 6, May 6, August 6 or November 6, respectively.

Any interest on any Debenture which is payable, but is not punctually paid or duly provided for, on any February 6, May 6, August 6 or November 6 (herein called “Defaulted Interest”) shall forthwith cease to be payable to the Debentureholder on the relevant record date by virtue of his having been such Debentureholder, and such Defaulted Interest shall be paid by the Company, at its election in each case, as provided in clause (1) or (2) below:

(a) The Company may elect to make payment of any Defaulted Interest to the Persons in whose names the Debentures (or their respective Predecessor Debentures) 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 to be paid on each Debenture and the date of the 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 prior to the date of the proposed payment, such money when deposited to be held in trust for the benefit of the Person entitled to such Defaulted Interest as in this clause provided. Thereupon the Trustee shall fix a special record date for the payment of such Defaulted Interest which shall be not more than 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 Trustee shall promptly notify the Company of such special record date and, in the name and at the expense of the Company, shall cause notice of the proposed payment of such Defaulted Interest and the special record date therefor to be mailed, first-class postage prepaid, to each Debentureholder at his address as it appears in the Debenture

register, not less than ten (10) days prior to such special record date. Notice of the proposed payment of such Defaulted Interest and the special record date therefor having been so mailed, such Defaulted Interest shall be paid to the Persons in whose names the Debentures (or their respective Predecessor Debentures) were 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 2.03.

(b) 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 Debentures 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 2.04 Execution of Debentures. The Debentures shall be signed in the name and on behalf of the Company by the manual or facsimile signature of its Chairman of the Board, Chief Executive Officer, President or any Vice President (whether or not designated by a number or numbers or word or words added before or after the title “Vice President”) and attested by the manual or facsimile signature of its Secretary or any of its Assistant Secretaries or its Treasurer or any of its Assistant Treasurers (which may be printed, engraved or otherwise reproduced thereon, by facsimile or otherwise). Only such Debentures as shall bear thereon a certificate of authentication substantially in the form set forth on the form of Debenture attached as Exhibit A hereto, manually executed by the Trustee (or an authenticating agent appointed by the Trustee as provided by Section 16.11), 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 Debenture executed by the Company shall be conclusive evidence that the Debenture 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 Debentures shall cease to be such officer before the Debentures so signed shall have been authenticated and delivered by the Trustee, or disposed of by the Company, such Debentures nevertheless may be authenticated and delivered or disposed of as though the person who signed such Debentures had not ceased to be such officer of the Company, and any Debenture may be signed on behalf of the Company by such persons as, at the actual date of the execution of such Debenture, 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.

Section 2.05 Exchange and Registration of Transfer Debentures; Restrictions on Transfer; Depositary.

(a) The Company shall cause to be kept at the Corporate Trust Office a register (the register maintained in such office and in any other office or agency of the Company designated pursuant to Section 5.02 being herein sometimes collectively referred to as the “Debenture register”) in which, subject to such reasonable regulations as it may prescribe, the Company shall provide for the registration of Debentures and transfers of Debentures. The Debenture register shall be in written form or in any form capable of being converted into written

form within a reasonably prompt period of time. The Trustee is hereby appointed “Debenture registrar” for the purpose of registering Debentures and transfers of Debentures as herein provided. The Company may appoint one or more co-registrars in accordance with Section 5.02.

Upon surrender for registration of transfer of any Debenture to the Debenture registrar or any co-registrar, and satisfaction of the requirements for such transfer set forth in this Section 2.05, the Company shall execute,. and the Trustee shall authenticate and deliver, in the name of the designated transferee or transferees, one or more new Debentures of any authorized denominations and of a like aggregate principal amount and bearing such restrictive legends as may be required by this Indenture.

Debentures may be exchanged for other Debentures of any authorized denominations and of a like aggregate principal amount, upon surrender of the Debentures to be exchanged at any such office or agency maintained by the Company pursuant to Section 5.02. Whenever any Debentures are so surrendered for exchange, the Company shall execute, and the Trustee shall authenticate and deliver, the Debentures which the Debentureholder making the exchange is entitled to receive bearing registration numbers not contemporaneously outstanding.

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

All Debentures presented or surrendered for registration of transfer or for exchange, redemption or conversion shall (if so required by the Company or the Debenture registrar) be duly endorsed, or be accompanied by a written instrument or instruments of transfer in form satisfactory to the Company, and the Debentures shall be duly executed by the Debentureholder thereof or the Debentureholder’s attorney duly authorized in writing.

No service charge shall be made for any registration of transfer or exchange of Debentures, but the Company may require payment of a sum sufficient to cover any tax, assessment or other governmental charge that may be imposed in connection with any registration of transfer or exchange of Debentures.

Neither the Company nor the Trustee nor any Debenture registrar shall be required to exchange or register a transfer of (a) any Debentures for a period of fifteen (15) days next preceding any selection of Debentures to be redeemed, (b) any Debentures or portions thereof called for redemption pursuant to Section 3.02, (c) any Debentures or portions thereof surrendered for conversion pursuant to Article 15 or (d) any Debentures or portions thereof tendered for redemption (and not withdrawn) pursuant to Section 3.06.

(b) So long as the Debentures are eligible for book-entry settlement with the Depositary, or unless otherwise required by law, all Debentures that, upon initial issuance are beneficially owned by QIBs or as a result of a sale or transfer after initial issuance are beneficially owned by QIBs, will be represented by one or more Debentures in global form registered in the name of the Depositary or the nominee of the Depositary (the “Global Debenture”), except as otherwise specified below. The transfer and exchange of beneficial

interests in any such Global Debenture shall be effected through the Depositary in accordance with this Indenture and the procedures of the Depositary therefor. The Trustee shall make appropriate endorsements to reflect increases or decreases in the principal amounts of any such Global Debenture as set forth on the face of the Debenture (“Principal Amount”) to reflect any such transfers. Except as provided below, beneficial owners of a Global Debenture shall not be entitled to have certificates registered in their names, will not receive or be entitled to receive physical delivery of certificates in definitive form and will not be considered holders of such Global Debenture.

(c) So long as the Debentures are eligible for book-entry settlement with the Depositary, or unless otherwise required by law, upon any transfer of a definitive Debenture to a QIB in accordance with Rule 144A, and upon receipt of the definitive Debenture or Debentures being so transferred, together with a certification, substantially in the form on the reverse of the Debenture, from the transferor that the transfer is being made in compliance with Rule 144A (or other evidence satisfactory to the Trustee), the Trustee shall make an endorsement on the Global Debenture to reflect an increase in the aggregate Principal Amount of the Debentures represented by such Global Debenture, and the Trustee shall cancel such definitive Debenture or Debentures in accordance with the standing instructions and procedures of the Depositary, the aggregate Principal Amount of the Debentures represented by such Global Debenture to be increased accordingly; provided, however, that no definitive Debenture, or portion thereof, in respect of which the Company or an Affiliate of the Company held any beneficial interest shall be included in such Global Debenture until such definitive Debenture is freely tradable in accordance with Rule 144(k) under the Securities Act, provided further that the Trustee shall issue Debentures in definitive form upon any transfer of a beneficial interest in the Global Debenture to the Company or any Affiliate of the Company.

Upon any sale or transfer of a Debenture to an Institutional Accredited Investor (other than pursuant to a registration statement that has been declared effective under the Securities Act), such Institutional Accredited Investor shall, prior to such sale or transfer, furnish to the Company and/or the Trustee a signed letter containing representations and agreements relating to restrictions on transfer substantially in the form set forth in Exhibit B to this Indenture. Upon any transfer of a beneficial interest in the Global Debenture to an Institutional Accredited Investor, the Trustee shall make an endorsement on the Global Debenture to reflect a decrease in the aggregate Principal Amount of the Debentures represented by such Global Debenture, and the Company shall execute a definitive Debenture or Debentures in exchange therefore, and the Trustee, upon receipt of such definitive Debenture or Debentures and the written order of the Company, shall authenticate and deliver such definitive Debenture or Debentures.

Any Debenture in global form 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. in order for the Debentures to be eligible for The Portal Market or as may be required for the Debentures to be tradable on any other market developed for trading of securities pursuant to Rule 144A or required 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 Debentures may be listed or traded or to conform with any usage with respect thereto, or to indicate any special limitations or restrictions to which any particular Debentures are subject.

(d) Every Debenture that bears or is required under this Section 2.05(d) to bear the legend set forth in this Section 2.05(d) (together with any Common Stock issued upon conversion of the Debentures and required to bear the legend set forth in Section 2.05(e), collectively, the “Restricted Securities”) shall be subject to the restrictions on transfer set forth in this Section 2.05(d) (including those set forth in the legend set forth below) unless such restrictions on transfer shall be waived by written consent of the Company, and the holder of each such Restricted Security, by such Debentureholder’s acceptance thereof, agrees to be bound by all such restrictions on transfer. As used in Sections 2.05(d) and 2.05(e), the term “transfer” encompasses any sale, pledge, loan, transfer or other disposition whatsoever of any Restricted Security.

Until the expiration of the holding period applicable to sales thereof under Rule 144(k) under the Securities Act (or any successor provision), any certificate evidencing such Debenture (and all securities issued in exchange therefor or substitution thereof, other than Common Stock, if any, issued upon conversion thereof, which shall bear the legend set forth in Section 2.05(e), if applicable) shall bear a legend in substantially the following form, unless such Debenture has been sold pursuant to a registration statement that has been declared effective under the Securities Act (and which continues to be effective at the time of such transfer), or unless otherwise agreed by the Company in writing, with written notice thereof to the Trustee:

THE SECURITY AND THE SHARES OF 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, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION. EACH PURCHASER OF THIS SECURITY IS HEREBY NOTIFIED THAT THE SELLER OF THIS SECURITY MAY BE RELYING ON THE EXEMPTION FROM THE PROVISIONS OF SECTION 5 OF THE SECURITIES ACT PROVIDED BY RULE 144A THEREUNDER.

TO MENTOR GRAPHICS CORPORATION 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 TOA REGISTRATION STATEMENT WHICH 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 MENTOR GRAPHICS CORPORATION’S AND THE TRUSTEE’S RIGHT 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, A CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON THE OTHER SIDE OF THIS SECURITY IS COMPLETED AND DELIVERED BY THE TRANSFEROR TO THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.

Any Debenture (or security issued in exchange or substitution therefor) as to which such restrictions on transfer shall have expired in accordance with their terms or as to conditions for removal of the foregoing legend set forth therein have been satisfied may, upon surrender of such Debenture for exchange to the Debenture registrar in accordance with the provisions of this Section 2.05, be exchanged for a new Debenture or Debentures, of like tenor and aggregate principal amount, which shall not bear the restrictive legend required by this Section 2.05(d).

Notwithstanding any other provisions of this Indenture (other than the provisions set forth in the second paragraph of Section 2.05(c) and in this Section 2.05(d)), a Debenture in global form 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.

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 the Debentures in global form. Initially, the Global Debenture shall be issued to the Depositary, registered in the name of Cede & Co., as the nominee of the Depositary, and deposited with the Custodian for Cede & Co.

If at any time the Depositary for a Debenture in global form notifies the Company that it is unwilling or unable to continue as Depositary for such Debenture, the Company may appoint a successor Depositary with respect to such Debenture. If a successor Depositary is not appointed by the Company within ninety (90) days after the Company receives such notice, the Company

will execute, and the Trustee, upon receipt of an Officers’ Certificate for the authentication and delivery of Debentures, will authenticate and deliver, Debentures in certificated form, in aggregate principal amount equal to the principal amount of such Debenture in global form, in exchange for such Debenture in global form.

If a Debenture in certificated form is issued in exchange for any portion of a Debenture in global form after the close of business at the office or agency where such exchange occurs on any record date and before the opening of business at such office or agency on the next ,succeeding Interest Payment Date, interest will not be payable on such Interest Payment Date in respect of such certificated Debenture, but will be payable on such Interest Payment Date, subject to the provisions of Section 2.03, only to the Person to whom interest in respect of such portion of such Debenture in global form is payable in accordance with the provisions of this Indenture.

Debentures in certificated form issued in exchange for all or a part of a Debenture in global form pursuant to this Section 2.05 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 Debentures in certificated form to the Persons in whose names such Debentures in certificated form are so registered.

At such time as all interests in a Debenture in global form have been redeemed, converted, canceled, exchanged for Debentures in certificated form, or transferred to a transferee who receives Debentures in certificated form thereof, such Debenture in global form shall, upon receipt thereof, be 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 Debenture in global form is exchanged for Debentures in certificated form, redeemed, converted, repurchased or canceled, or transferred to a transferee who receives Debentures in certificated form therefor or any Debenture in certificated form is exchanged or transferred for part of a Debenture in global form, the principal amount of such Debenture in global form 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 Debenture in global form, by the Trustee or the Custodian, at the direction of the Trustee, to reflect such reduction or increase.

(e) Until the expiration of the holding period applicable to sales thereof under Rule 144(k) under the Securities Act (or any successor provision), any stock certificate representing Common Stock issued upon conversion of any Debenture shall bear a legend in substantially the following form, unless such Common Stock has been sold pursuant to a registration statement that has been declared effective under the Securities Act (and which continues to be effective at the time of such transfer) or such Common Stock has been issued upon conversion of Debentures that have been transferred pursuant to a registration statement that has been declared effective under the Securities Act, or unless otherwise agreed by the Company in writing with written notice thereof to the transfer agent:

THE SHARES OF COMMON STOCK HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES LAWS. NEITHER THE SHARES OF COMMON STOCK NOR ANY INTEREST OR PARTICIPATION THEREIN MAY BE REOFFERED, SOLD ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION. EACH PURCHASER OF THE SHARES OF COMMON STOCK IS HEREBY NOTIFIED THAT THE SELLER OF THESE SHARES OF COMMON STOCK MAY BE RELYING ON THE EXEMPTION FROM THE PROVISIONS OF SECTION 5 OF THE SECURITIES ACT PROVIDED BY RULE 144A THEREUNDER.

THE HOLDER OF THE SHARES OF COMMON STOCK, BY ITS ACCEPTANCE HEREOF, AGREES TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SHARES OF COMMON STOCK, PRIOR TO THE DATE (THE “RESALE RESTRICTION TERMINATION DATE”) WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH MENTOR GRAPHICS CORPORATION OR ANY AFFILIATE OF MENTOR GRAPHICS CORPORATION WAS THE OWNER OF THE SHARES OF COMMON STOCK (OR ANY PREDECESSOR OF SUCH SHARES OF COMMON STOCK) ONLY (A) TO MENTOR GRAPHICS CORPORATION OR ANY SUBSIDIARY THEREOF, (B) FOR SO LONG AS THE SHARES OF COMMON STOCK 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 TOA REGISTRATION STATEMENT WHICH 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 MENTOR GRAPHICS CORPORATION’S AND THE TRUSTEE’S RIGHT 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, A CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON THE OTHER SIDE OF THE SHARES OF COMMON STOCK ARE COMPLETED AND DELIVERED BY THE TRANSFEROR TO THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.

Any such Common Stock as to which such restrictions on transfer shall have expired in accordance with their terms or as to which the conditions for removal of the foregoing legend set forth therein have been satisfied may, upon surrender of the 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 certificate or certificates for a like number of shares of Common Stock, which shall not bear the restrictive legend required by this Section 2.05(e).

(f) Any Debenture or Common Stock issued upon the conversion or exchange of a Debenture that, prior to the expiration of the holding period applicable to sales thereof under Rule 144(k) under the Securities Act (or any successor provision), is 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 which results in such Debentures or Common Stock, as the case may be, no longer being “restricted securities” (as defined under Rule 144).

Section 2.06 Mutilated, Destroyed, Lost or Stolen Debentures. In case any Debenture 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 make available for delivery, a new Debenture, bearing a number not contemporaneously outstanding, in exchange and substitution for the mutilated Debenture, or in lieu of and in substitution for the Debenture so destroyed, lost or stolen. In every case the applicant for a substituted Debenture 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, 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 Debenture and of the ownership thereof.

Following receipt by the Trustee or such authenticating agent, as the case may be, of satisfactory security or indemnity and evidence, as described in the preceding paragraph, the Trustee or such authenticating agent may authenticate any such substituted Debenture and make available for delivery such Debenture. Upon the issuance of any substituted Debenture, the Company may require the payment 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 Debenture which has matured or is about to mature or has been called for redemption or has been tendered for redemption (and not withdrawn) or is to be converted into Common Stock shall become mutilated or be destroyed, lost or stolen, the Company may, instead of issuing a substitute Debenture, pay or authorize the payment of or convert or authorize the conversion of the same (without surrender thereof except in the case of a mutilated Debenture), 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, the applicant shall also furnish to the Company, the Trustee and, if applicable, any paying agent or conversion agent evidence to their satisfaction of the destruction, loss or theft of such Debenture and of the ownership thereof.

Every substitute Debenture issued pursuant to the provisions of this Section 2.06 by virtue of the fact that any Debenture is destroyed, lost or stolen shall constitute an additional contractual obligation of the Company, whether or not the destroyed, lost or stolen Debenture 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 Debentures duly issued hereunder. To the extent permitted by law, all Debentures shall be held and owned upon the express condition that the foregoing provisions are exclusive with respect to the replacement or payment or conversion of mutilated, destroyed, lost or stolen Debentures 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 2.07 Temporary Debentures. Pending the preparation of Debentures in certificated form, the Company may execute and the Trustee or an authenticating agent appointed by the Trustee shall, upon the written request of the Company, authenticate and deliver temporary Debentures (printed or lithographed). Temporary Debentures shall be issuable in any authorized denomination, and substantially in the form of the Debentures in certificated form, but with such omissions, insertions and variations as may be appropriate for temporary Debentures, all as may be determined by the Company. Every such temporary Debenture 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 Debentures in certificated form. Without unreasonable delay the Company will execute and deliver to the Trustee or such authenticating agent Debentures in certificated form (other than in the case of Debentures in global form) and thereupon any or all temporary Debentures (other than any such Debenture in global form) may be surrendered in exchange therefor, at each office or agency maintained by the Company pursuant to Section 5.02 and the Trustee or such authenticating agent shall authenticate and make available for delivery in exchange for such temporary Debentures an equal aggregate principal amount of Debentures in certificated form. Such exchange shall be made by the Company at its own expense and without any charge therefor. Until so exchanged, the temporary Debentures shall in all respects be entitled to the same benefits and subject to the same limitations under this Indenture as Debentures in certificated form authenticated and delivered hereunder.

Section 2.08 Cancellation of Debentures Paid, Etc. All Debentures surrendered for the purpose of payment, redemption, conversion, exchange or registration of transfer shall, if surrendered to the Company or any paying agent or any Debenture 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 Debentures shall be issued in lieu thereof except as expressly permitted by any of the provisions of this Indenture. The Trustee shall dispose of such canceled Debentures in accordance with its customary procedures. If the Company shall acquire any of the Debentures, such acquisition shall not operate as a redemption or satisfaction of the indebtedness represented by such Debentures unless and until the same are delivered to the Trustee for cancellation.

Section 2.09 CUSIP Numbers. The Company in issuing the Debentures may use “CUSIP” numbers (if then generally in use), and, if so, the Trustee shall use “CUSIP” numbers in notices of redemption as a convenience to Debentureholders; provided, however, that any such notice may state that no representation is made as to the correctness of such numbers either as printed on the Debentures or as contained in any notice of a redemption and that reliance may be placed only on the other identification numbers printed on the Debentures, and any such redemption shall not be affected by any defect in or omission of such numbers. The Company will promptly notify the Trustee of any change in the “CUSIP” numbers.

Section 3.01 Optional Redemption by the Company. The Company may not redeem the Debentures at its option at any time prior to August 6, 2007.

(a) At any time and from time to time on or after August 6, 2007, and prior to maturity, the Debentures may be redeemed at the option of the Company, in whole or in part, upon notice as set forth in Section 3.02, at the following redemption prices (expressed as percentages of the principal amount) together with accrued and unpaid interest, if any (including Liquidated Damages, if any) to, but excluding, the date fixed for redemption:

and 100% on August 6, 2010 and at all times thereafter; provided, however, that if the date fixed for redemption is on a February 6, May 6, August 6 or November 6, then the interest payable on such date shall be paid to the holder of record on the preceding January 21, April 21, July 21 or October 21, respectively.

Section 3.02 Notice of Redemptions; Selection of Debentures. In case the Company shall desire to exercise the right to redeem all or, as the case may be, any part of the Debentures pursuant to Section 3.01, it shall fix a date for redemption and it or, at its written request received by the Trustee not fewer than thirty (30) days prior (or such shorter period of time as may be acceptable to the Trustee) to the date fixed for redemption, the Trustee in the name of and at the expense of the Company, shall mail or cause to be mailed a notice of such redemption not fewer than twenty (20) nor more than sixty (60) days prior to the date fixed for redemption to the holders of Debentures so to be redeemed as a whole or in part at their last addresses as the same appear on the Debenture register; provided, however, that if the Company shall give such notice, it shall also give written notice, and written notice of the Debentures to be redeemed, to the Trustee. Such mailing shall be by first class mail. The notice if mailed in the manner herein provided shall be conclusively presumed to have been duly given, whether or not the holder receives such notice. In any case, failure to give such notice by mail or any defect in the notice to the holder of any Debenture designated for redemption as a whole or in part shall not affect the validity of the proceedings for the redemption of any other Debenture. Concurrently with the mailing of any such notice of redemption, the Company shall issue a press release announcing such redemption, the form and content of which press release shall be determined by the Company in its sole discretion. The failure to issue any such press release or any defect therein shall not affect the validity of the redemption notice or any of the proceedings for the redemption of any Debenture called for redemption.

Each such notice of redemption shall specify the aggregate principal amount of Debentures to be redeemed, the CUSIP number or numbers of the Debentures being redeemed, the date fixed for redemption (which shall be a Business Day), the redemption price at which Debentures are to be redeemed, the place or places of payment, that payment will be made upon presentation and surrender of such Debentures, that interest accrued to the date fixed for redemption will be paid as specified in said notice, and that on and after said date interest thereon or on the portion thereof to be redeemed will cease to accrue. Such notice shall also state the current Conversion Rate and approximate Conversion Price and the date on which the right to convert such Debentures or portions thereof into Common Stock will expire. If fewer than all the Debentures are to be redeemed, the notice of redemption shall identify the Debentures to be redeemed (including CUSIP numbers, if any). In case any Debenture is to be redeemed in part only, the notice of redemption shall state the portion of the principal amount thereof to be redeemed and shall state that, on and after the date fixed for redemption, upon surrender or such Debenture, a new Debenture or Debentures in principal amount equal to the unredeemed portion thereof will be issued.

On or prior to the redemption date specified in the notice of redemption given as provided in this Section 3.02, the Company will deposit with the Trustee or with one or more paying agents (or, if the Company is acting as its own paying agent, set aside, segregate and hold in trust as provided in Section 5.04(b)) an amount of money in immediately available funds sufficient to redeem on the redemption date all the Debentures (or portions thereof) so called for redemption (other than those theretofore surrendered for conversion into Common Stock) at the appropriate redemption price, together with accrued interest to, but excluding, the date fixed for redemption; provided, however, that if such payment is made on the redemption date it must be received by the Trustee or paying agent, as the case may be, by 10:00 a.m. New York City time on such date. The Company shall be entitled to retain any interest, yield or gain on amounts

deposited with the Trustee or any paying agent pursuant to this Section 3.02 in excess of amounts required hereunder to pay the redemption price together with accrued interest to, but excluding, the date fixed for redemption. If any Debenture called for redemption is converted pursuant hereto prior to such redemption, any money deposited with the Trustee or any paying agent or so segregated and held in trust for the redemption of such Debenture shall be paid to the Company upon its written request, or, if then held by the Company, shall be discharged from such trust. Whenever any Debentures are to be redeemed, the Company will give the Trustee written notice in the form of an Officers’ Certificate not fewer than thirty (30) days (or such shorter period of time as may be acceptable to the Trustee) prior to the redemption date as to the aggregate principal amount of Debentures to be redeemed.

If less than all of the outstanding Debentures are to be redeemed, the Trustee shall select the Debentures or portions thereof of the Global Debenture or the Debentures in certificated form to be redeemed (in principal amounts of $1,000 or integral multiples thereof) by lot, on a pro rata basis or by another method the Trustee deems fair and appropriate. If any Debenture selected for partial redemption is submitted for conversion in part after such selection, the portion of such Debenture submitted for conversion shall be deemed (so far as may be) to be the portion to be selected for redemption. The Debentures (or portions thereof) so selected shall be deemed duly selected for redemption for all purposes hereof, notwithstanding that any such Debenture is submitted for conversion in part before the mailing of the notice of redemption.

Upon any redemption of less than all of the outstanding Debentures, the Company and the Trustee may (but need not), solely for purposes of determining the pro rata allocation among such Debentures as are unconverted and outstanding at the time of redemption, treat as outstanding any Debentures surrendered for conversion during the period of fifteen (15) days next preceding the mailing of a notice of redemption and may (but need not) treat as outstanding any Debenture authenticated and delivered during such period in exchange for the unconverted portion of any Debenture converted in part during such period.

Section 3.03 Payment of Debentures Called for Redemption. If notice of redemption has been given as above provided, the Debentures or portion of Debentures with respect to which such notice has been given shall, unless converted into Common Stock pursuant to the terms hereof, become due and payable on the date fixed for redemption and at the place or places stated in such notice at the applicable redemption price, together with interest accrued to (but excluding) the date fixed for redemption, and on and after said date (unless the Company shall default in the payment of such Debentures at the redemption price, together with interest accrued to said date) interest on the Debentures or portion of Debentures so called for redemption shall cease to accrue and, after the close of business on the Business Day next preceding the date fixed for redemption, such Debentures shall cease to be convertible into Common Stock and, except as provided in Sections 8.05 and 13.04, to be entitled to any benefit or security under this Indenture, and the holders thereof shall have no right in respect of such Debentures except the right to receive the redemption price thereof and unpaid interest to (but excluding) the date fixed for redemption. On presentation and surrender of such Debentures at a place of payment in said notice specified, the said Debentures or the specified portions thereof shall be paid and redeemed by the Company at the applicable redemption price, together with interest accrued thereon to (but excluding) the date fixed for redemption; provided, however, that if the applicable redemption date is an Interest Payment Date, the quarterly payment of interest becoming due on such date shall be payable to the holders of such Debentures registered as such on the relevant record date instead of the holders surrendering such Debentures for redemption on such date.

Upon presentation of any Debenture redeemed in part only, the Company shall execute and the Trustee shall authenticate and make available for delivery to the holder thereof, at the expense of the Company, a new Debenture or Debentures, of authorized denominations, in principal amount equal to the unredeemed portion of the Debentures so presented.

Notwithstanding the foregoing, the Trustee shall not redeem any Debentures or mail any notice of redemption during the continuance of a default in payment of interest or premium, if any, on the Debentures. If any Debenture called for redemption shall not be so paid upon surrender thereof for redemption, the principal and premium, if any, shall, until paid or duly provided for, bear interest from the date fixed for redemption at the rate borne by the Debenture and such Debenture shall remain convertible into Common Stock until the principal and premium, if any, and interest shall have been paid or duly provided for.

Section 3.04 Conversion Arrangement on Call for Redemption. In connection with any redemption of Debentures, the Company may arrange for the purchase and conversion of any Debentures by an agreement with one or more investment bankers or other purchasers to purchase such Debentures by paying to the Trustee in trust for the Debentureholders, on or before the date fixed for redemption, an amount not less than the applicable redemption price, together with interest accrued to (but excluding) the date fixed for redemption, of such Debentures. Notwithstanding anything to the contrary contained in this Article 3, the obligation of the Company to pay the redemption price of such Debentures, together with interest accrued to (but excluding) the date fixed for redemption, shall be deemed to be satisfied and discharged to the extent such amount is so paid by such purchasers. If such an agreement is entered into, a copy of which will be filed with the Trustee prior to the date fixed for redemption, any Debentures not duly surrendered for conversion by the holders thereof may, at the option of the Company, be deemed, to the fullest extent permitted by law, acquired by such purchasers from such holders and (notwithstanding anything to the contrary contained in Article 15) surrendered by such purchasers for conversion, all as of immediately prior to the close of business on the date fixed for redemption (and the right to convert any such Debentures shall be extended through such time), subject to payment of the above amount as aforesaid. At the direction of the Company, the Trustee shall hold and dispose of any such amount paid to it in the same manner as it would monies deposited with it by the Company for the redemption of Debentures. Without the Trustee’s prior written consent, no arrangement between the Company and such purchasers for the purchase and conversion of any Debentures shall increase or otherwise affect any of the powers, duties, responsibilities or obligations of the Trustee as set forth in this Indenture.

(a) General. At the option of the Debentureholder, the Debentures shall be purchased by the Company on August 6, 2010, August 6, 2013 and August 6, 2018 (each, a “Purchase Date”), at 100% of the principal amount of the Debentures in cash, together with any accrued and unpaid interst to, but excluding, the Purchase Date (the “Purchase Price”), upon:

(i) delivery to the Paying Agent by the Debentureholder of a written notice of purchase (a “Purchase Notice”), at any time from the opening of business on the date that is 30 days prior to a Purchase Date until the close of business on the Purchase Date stating:

(A) if certificated Debentures have been issued, the certificate number of the Debenture which the Debentureholder will deliver to be purchased, or if no certificated Debentures have been issued, such information as may be required under the applicable procedures of the Depositary and the Indenture;

(B) the portion of the Principal Amount of the Debenture which the Debentureholder will deliver to be purchased, which portion must be in a Principal Amount of $1,000 or integral multiples thereof; and

(C) that such Debenture shall be purchased as of the Purchase Date pursuant to the terms and conditions specified in the Securities and in this Indenture; and

(ii) delivery of such Debenture to the Paying Agent for cancellation prior to, on or after the Purchase Date (together with all necessary endorsements) at the offices of the Paying Agent, such delivery being a condition to receipt by the Debentureholder of the Purchase Price therefor; provided, however, that such Purchase Price shall be so paid pursuant to this Section 3.05 only if the Debenture so delivered to the Paying Agent shall conform in all respects to the description thereof in the related Purchase Notice.

(iii) The Company shall purchase from the Debentureholder thereof, pursuant to this Section 3.05, a portion of a Debenture if the Principal Amount of such portion is $1,000 or an integral multiple of $1,000 if so requested by the Debentureholder. Provisions of this Indenture that apply to the purchase of all of a Debenture also apply to the purchase of such portion of such Debenture.

(iv) Any purchase by the Company contemplated pursuant to the provisions of this Section 3.05 shall be consummated by the delivery of the consideration to be received by the Debentureholder promptly following the later of the Purchase Date and the time of delivery of the Debenture.

(v) Notwithstanding anything herein to the contrary, any Debentureholder delivering to the Paying Agent the Purchase Notice contemplated by this Section 3.05(a)(i) shall have the right to withdraw such Purchase Notice at any time prior to the close of business on the Purchase Date by delivery of a written notice of withdrawal to the Paying Agent that states:

(b) if certificated Debentures have been issued, the certificate numbers of the withdrawn Debentures (or, if the Debentures are not certificated, the withdrawal notice must comply with appropriate DTC procedures); and

The Paying Agent shall promptly notify the Company of the receipt by it of any Purchase Notice or written notice of withdrawal thereof.

(b) Company Notice. The Company shall deliver a notice (the “Company Notice”) to Debentureholders (and to beneficial owners as required by applicable law) not less than 30 days prior to such Purchase Date (the “Company Notice Date”). The Company Notice shall be delivered to all Debentureholders at their respective addresses shown in the Register, shall include a form of Purchase Notice to be completed by a Debentureholder and shall include the following information:

(i) the Purchase Price, the Conversion Rate and the approximate Conversion Price applicable on the Company Notice Date;

(ii) that the Purchase Notice must be delivered by each Debentureholder electing to have the Cmpany purchase such Debentureholder’s Debentures (or a portion thereof) as of the Purchase Date to the Paying Agent;

(iv) that Debentures as to which a Purchase Notice has been given by the Debentureholder may be converted pursuant to Article 15 hereof only if the applicable Purchase Notice has been withdrawn in accordance with the terms of this Indenture;

(v) that Debenture must be surrendered (by physical delivery at the office of the Paying Agent in the case of certificated Debentures, or otherwise by book-entry transfer) to the Paying Agent for cancellation to collect payment;

(vi) that the Purchase Price for any Debenture as to which a Purchase Notice has been given and not withdrawn will be paid promptly following the later of the Purchase Date and the time of surrender of such Debenture as described in (iv);

(vii) the procedures the Debentureholder must follow to exercise rights under Section 3.05 and a brief description of those rights;

(x) that, unless the Company defaults in making payment of such Purchase Price, interest and Liquidated Damages, if any, on Debentures covered by any Purchase Notice will cease to accrue on and after the Purchase Date; and

(c) Procedure upon Purchase. On or prior to the Purchase Date, the Company will deposit with the Trustee or with one or more paying agents (or, if the Company is acting as its own paying agent, set aside, segregate and hold in trust as provided in Section 5.04(b)) an amount of money sufficient to pay on the Purchase Date all the Debentures to be purchased on such date at the appropriate repurchase price, together with accrued interest to (but excluding) the Purchase Date; provided, however, that if such payment is made on the Purchase Date it must be received by the Trustee or paying agent, as the case may be, by 10:00 a.m. New York City time, on such date. Payment for Debentures surrendered for purchase (and not withdrawn) prior to the Purchase Date will be made promptly (but in no event more than five (5) Business Days) following the Purchase Date by mailing checks for the amount payable to the holders of such Debentures entitled thereto as they shall appear on the registry books of the Company.

Section 3.06 Repurchase at Option of Debentureholders upon a Change of Control.

(a) If there shall occur a Change of Control at any time prior to maturity of the Debentures, then each Debentureholder shall have the right, at such holder’s option, to require the Company to repurchase all of such holder’s Debentures, or any portion thereof that is an integral multiple of $1,000 principal amount, on the date set by the Company for such repurchase (the “Repurchase Date”) that is no earlier than twenty-five (25) days and no later than thirty-five (35) days after the date of the Company Change of Control Notice (as defined in Section 3.06(b) below) of such Change of Control at a repurchase price equal to 100% of the principal amount thereof, together with accrued and unpaid interest (including Liquidated Damages, if any) to (but excluding) the Repurchase Date; provided, however, that, if such Repurchase Date is a February 6, May 6, August 6 or November 6, then the interest payable on such date shall be paid to the holders of record of the Debentures on the next preceding January 21, April 21, July 21 or October 21, respectively.

Upon presentation of any Debenture repurchased in part only, the Company shall execute and, upon the Company’s written direction to the Trustee, the Trustee shall authenticate and deliver to the holder thereof, at the expense of the Company, a new Debenture or Debentures, of authorized denominations, in principal amount equal to the unrepurchased portion of the Debentures so presented.

(b) On or before the 30th day after the occurrence of a Change of Control, the Company or at its written request (which must be received by the Trustee at least five (5) Business Days prior to the date the Trustee is requested to give notice as described below, unless the Trustee shall agree in writing to a shorter period), the Trustee in the name of and at the expense of the Company, shall mail or cause to be mailed to all holders of record on the date of the Change of Control a notice (the “Company Change of Control Notice”) of the occurrence of such Change of Control and of the redemption right at the option of the holders arising as a result thereof. Such notice shall be mailed in the manner and with the effect set forth in the first paragraph of Section 3.02 (without regard for the time limits set forth therein). If the Company shall give such notice, the Company shall also deliver a copy of the Company Change of Control Notice to the Trustee at such time as it is mailed to Debentureholders. Concurrently with or prior to the mailing of any Company Change of Control Notice, the Company shall issue a press release announcing such Change of Control referred to in the Company Change of Control Notice, the form and content of which press release shall be determined by the Company in its

sole discretion. The failure to issue any such press release or any defect therein shall not affect the validity of the Company Change of Control Notice or any proceedings for the repurchase of any Debenture which any Debentureholder may elect to have the Company repurchase as provided in this Section 3.06.

Each Company Change of Control Notice shall specify the circumstances constituting the Change of Control, the Repurchase Date, the price at which the Company shall be obligated to repurchase Debentures, that the holder must exercise the repurchase right by giving written notice to the Trustee together with the Debentures with respect to which the repurchase right is being exercised on or prior to the close of business on the Business Day that is five (5) Business Days prior to the Repurchase Date, the Conversion Rate and approximate Conversion Price applicable on the Repurchase Date that the holder shall have the right to withdraw any Debentures surrendered prior to the close of business on the Business Day immediately preceding the Repurchase Date, a description of the procedure which a Debentureholder must follow to exercise such repurchase right and to withdraw any surrendered Debentures, the place or places where the holder is to surrender such holder’s Debentures, and the amount of interest accrued on each Debenture to the Repurchase Date.

No failure of the Company to give the foregoing notices and no defect therein shall limit the Debentureholders’ redemption rights or affect the validity of the proceedings for the repurchase of the Debentures pursuant to this Section 3.06.

(c) For a Debenture to be so repurchased at the option of the holder, the Company must receive at the office or agency of the Company maintained for that purpose or, at the option of such holder, the Corporate Trust Office, such Debenture with the form entitled “Option to Elect Repayment Upon A Change of Control” (a “Repurchase Notice”) on the reverse thereof duly completed, together with such Debentures duly endorsed for transfer, on or before the Change of Control Expiration Time. All questions as to the validity, eligibility (including time of receipt) and acceptance of any Debenture for repayment shall be determined by the Company, whose determination shall be final and binding absent manifest error.

(d) On or prior to the Repurchase Date, the Company will deposit with the Trustee or with one or more paying agents (or, if the Company is acting as its own paying agent, set aside, segregate and hold in trust as provided in Section 5.04(b)) an amount of money sufficient to repay on the Repurchase Date all the Debentures to be repurchased on such date at the appropriate repurchase price, together with accrued interest to (but excluding) the Repurchase Date; provided, however, that if such payment is made on the Repurchase Date it must be received by the Trustee or paying agent, as the case may be, by 10:00 a.m. New York City time, on such date. Payment for Debentures surrendered for repurchase (and not withdrawn) prior to the Change of Control Expiration Time will be made promptly (but in no event more than five (5) Business Days) following the Repurchase Date by mailing checks for the amount payable to the holders of such Debentures entitled thereto as they shall appear on the registry books of the Company.

(e) In the case of a reclassification, change, consolidation, merger, combination, sale or conveyance to which Section 15.06 applies, in which the Common Stock of the Company is changed or exchanged as a result into the right to receive stock, securities or

other property or assets (including cash), which includes shares of Common Stock of the Company or shares of common stock of another Person that are, or upon issuance will be, traded on a United States national securities exchange or approved for trading on an established automated over-the-counter trading market in the United States and such shares constitute at the time such change or exchange becomes effective in excess of 50% of the aggregate fair market value of such stock, securities or other property or assets (including cash) (as determined by the Company, which determination shall be conclusive and binding), then the Person formed by such consolidation or resulting from such merger or which acquires such assets, as the case may be, shall execute and deliver to the Trustee a supplemental indenture (accompanied, upon Trustee’s request, by an Opinion of Counsel that such supplemental indenture complies with the Trust Indenture Act as in force at the date of execution of such supplemental indenture) modifying the provisions of this Indenture relating to the right of holders of the Debentures to cause the Company to repurchase the Debentures following a Change of Control, including without limitation the applicable provisions of this Section 3.06 and the definitions of Common Stock and Change of Control, as appropriate, as determined in good faith by the Company (which determination shall be conclusive and binding), to make such provisions apply to such other Person if different from the Company and the common stock issued by such Person (in lieu of the Company and the Common Stock of the Company).

(f) The Company will comply with the provisions of Rule 13e-4 and any other tender offer rules under the Exchange Act to the extent then applicable in connection with the repurchase rights of the holders of Debentures in the event of a Change of Control.

Section 4.01 Agreement of Subordination. The Company covenants and agrees, and each holder of Debentures issued hereunder by its acceptance thereof likewise covenants and agrees, that all Debentures shall be issued subject to the provisions of this Article 4, and each Person holding any Debenture, whether upon original issue or upon registration of transfer, assignment or exchange thereof, accepts and agrees to be bound by such provisions.

The payment of the principal of, premium, if any, and interest (including Liquidated Damages, if any) on all Debentures (including, but not limited to, the redemption price with respect to the Debentures called for redemption in accordance with Section 3.02 or submitted for repurchase in accordance with Section 3.06, as the case may be, as provided in this Indenture) issued hereunder shall, to the extent and in the manner hereinafter set forth, be subordinated and subject in right of payment to the prior payment in full of all Senior Debt, whether outstanding at the date of this Indenture or thereafter incurred.

No provision of this Article 4 shall prevent the occurrence of any default or Event of Default hereunder.

Section 4.02 Payments to Debentureholders. No payment shall be made with respect to the principal of, premium, if any, or interest (including Liquidated Damages, if any) on the Debentures (including, but not limited to, the redemption price with respect to the Debentures to be called for repurchase in accordance with Section 3.02 or submitted for redemption in accordance with Section 3.06, as the case may be, as provided in this Indenture), except payments and distributions made by the Trustee as permitted by the first or second paragraph of Section 4.05, if:

(i) a default in the payment of principal, premium, if any, interest, rent or other obligations in respect of Designated Senior Debt occurs and is continuing (or, in the case of Designated Senior Debt for which there is a period of grace, in the event of such a default that continues beyond the period of grace, if any, specified in the instrument or lease evidencing such Designated Senior Debt) (a “Payment Default”); or

(ii) a default, other than a Payment Default, on any Designated Senior Debt occurs and is continuing that then permits holders of such Designated Senior Debt or a Representative thereof to accelerate its maturity (or in the case of any lease, a default occurs and is continuing that permits the lessor to either terminate the lease or require the Company to make an irrevocable offer to terminate the lease following an event of default thereunder) and the Trustee receives a notice of the default (a “Payment Blockage Notice”) from a holder of Designated Senior Debt, a Representative of Designated Senior Debt or the Company (a “NonPayment Default”).

Notwithstanding the foregoing, only one Payment Blockage Notice with respect to the same event of default or any other events of default existing or continuing (whether such events are known or unknown to the Person giving the Payment Blockage Notice) at the time of notice on the same issue of Designated Senior Debt may be given during any period of 360 consecutive days unless the event of default or other events of default have been cured or waived for a period of not less than 90 consecutive days. No new payment blockage period may be commenced by the holders of Designated Senior Debt during any period of 360 consecutive days unless all events of default which triggered the preceding Payment Blockage Notice, and any other event of default existing or continuing at the time of such notice, have been waived or cured.

The Company may and shall resume payments on and distributions in respect of the Debentures:

(1) in the case of a Pyament Default, upon the date on which any such Payment Default is cured or waived or ceases to exist, or

(2) in the case of a Non-Payment Default, the earlier of (a) the date upon which such default is cured or waived or ceases to exist or (b) 180 days after the applicable Payment Blockage Notice is received by the Trustee if the maturity of such Designated Senior Debt has not been accelerated (or in the case of any lease, 180 days after notice is received if the Company has not received notice that the lessor under such lease has exercised its right to terminate the lease or require the Company to make an irrevocable offer to terminate the lease following an event of default thereunder),

in each case unless this Article 4 otherwise prohibits the payment or distribution at the time of such payment or distribution.

Upon any payment by the Company, or distribution of assets of the Company of any kind or character, whether in cash, property or securities, to creditors upon any dissolution or winding up or liquidation or reorganization of the Company, whether voluntary or involuntary or in bankruptcy, insolvency, receivership or other proceedings, or upon any acceleration of the Principal Amount due on the Debentures because of an Event of Default, all amounts due or to become due upon all Senior Debt shall first be paid in full in cash or other payment satisfactory to the holders of such Senior Debt (and satisfactory to the holders of Designated Senior Debt in the case such Senior Debt includes Designated Senior Debt), or payment thereof in accordance with its terms provided for in cash or other payment satisfactory to the holders of such Senior Debt (and satisfactory to the holders of Designated Senior Debt in the case such Senior Debt includes Designated Senior Debt) before any payment is made on account of the principal of, premium, if any, or interest (including Liquidated Damages, if any) on the Debentures (except payments made pursuant to Article 13 from monies deposited with the Trustee pursuant thereto prior to commencement of proceedings for such dissolution, winding up, liquidation or reorganization), and upon any such dissolution or winding up or liquidation or reorganization of the Company or bankruptcy, insolvency, receivership or other similar proceeding, or upon any acceleration of the Principal Amount due on the Debentures because of an Event of Default, any payment by the Company, or distribution of assets of the Company of any kind or character, whether in cash, property or securities, to which the holders of the Debentures or the Trustee would be entitled, except for the provisions of this Article 4, shall (except as aforesaid) be paid by the Company or by any receiver, trustee in bankruptcy, liquidating trustee, agent or other Person making such payment or distribution, or by the holders of the Debentures or by the Trustee under this Indenture if received by them or it, directly to the holders of Senior Debt (pro rata to such holders on the basis of the respective amounts of Senior Debt held by such holders, or as otherwise required by law or a court order) or their Representative or Representatives, as their respective interests may appear, to the extent necessary to pay all Senior Debt in full, in cash or other payment satisfactory to the holders of such Senior Debt (and satisfactory to the holders of Designated Senior Debt in the case such Senior Debt includes Designated Senior Debt), after giving effect to any concurrent payment or distribution to or for the holders of Senior Debt, before any payment or distribution is made to the holders of the Debentures or to the Trustee.

For purposes of this Article 4, the words, “cash, property or securities” shall not be deemed to include shares of stock of the Company as reorganized or readjusted, or securities of the Company or any other corporation provided for by a plan of reorganization or readjustment, the payment of which is subordinated at least to the extent provided in this Article 4 with respect to the Debentures to the payment of all Senior Debt which may at the time be outstanding provided that (i) the Senior Debt is assumed by the new corporation, if any, resulting from any reorganization or readjustment, and (ii) the rights of the holders of Senior Debt (other than leases which are not assumed by the Company or the new corporation, as the case may be) are not, without the consent of such holders, altered by such reorganization as the case may be) are not, without the consent of such holders, altered by such reorganization or readjustment. The consolidation of the Company with, or the merger of the Company into, another corporation or the liquidation or dissolution of the Company following the conveyance or transfer of its property as an entirety, or substantially as an entirety, to another Person upon the terms and conditions provided for in Article 12 shall not be deemed a dissolution, winding-up, liquidation or reorganization for the purposes of this Section 4.02 if such other Person shall, as a part of such consolidation, merger, conveyance or transfer, comply with the conditions stated in Article 12.

In the event of the acceleration of the Debentures because of an Event of Default, no payment or distribution shall be made to the Trustee or any holder of Debentures in respect of the principal of, premium, if any, or interest (including Liquidated Damages, if any) on the Debentures (including, but not limited to, the redemption price with respect to the Debentures called for redemption in accordance with Section 3.02 or submitted for redemption in accordance with Section 3.06, as the case may be, as provided in this Indenture), except payments and distributions made by the Trustee as permitted by the first or second paragraph of Section 4.05, until all Senior Debt has been paid in full in cash or other payment satisfactory to the holders of Senior Debt (and satisfactory to the holders of Designated Senior Debt in the case such Senior Debt includes Designated Senior Debt) or such acceleration is rescinded in accordance with the terms of this Indenture. If payment of the Debentures is accelerated because of an Event of Default, the Company or the Trustee shall promptly notify holders of Senior Debt of the acceleration.

In the event that, notwithstanding the foregoing provisions, any payment or distribution of assets of the Company of any kind or character, whether in cash, property or securities (including, without limitation, by way of setoff or otherwise), prohibited by the foregoing provisions in this Section 4.02, shall be received by the Trustee or the holders of the Debentures before all Senior Debt is paid in full in cash or other payment satisfactory to the holders of such Senior Debt (and satisfactory to the holders of Designated Senior Debt in the case such Senior Debt includes Designated Senior Debt), or provision is made for such payment thereof in accordance with its terms in cash or other payment satisfactory to the holders of such Senior Debt (and satisfactory to the holders of Designated Senior Debt in the case such Senior Debt includes Designated Senior Debt), such payment or distribution shall be held in trust for the benefit of and shall be paid over or delivered to the holders of Senior Debt or their Representative or Representatives, as their respective interests may appear, as calculated by the Company, for application to the payment of any Senior Debt remaining unpaid to the extent necessary to pay all Senior Debt in full in cash or other payment satisfactory to the holders of such Senior Debt (and satisfactory to the holders of Designated Senior Debt in the case such Senior Debt includes Designated Senior Debt), after giving effect to any concurrent payment or distribution to or for the holders of such Senior Debt.

Nothing in this Section 4.02 shall apply to claims of, or payments to, the Trustee under or pursuant to Section 8.06. This Section 4.02 shall be subject to the further provisions of Section 4.05.

Section 4.03 Subrogation of Debentures. Subject to the payment in full of all Senior Debt, the rights of the holders of the Debentures shall be subrogated to the extent of the payments or distributions made to the holders of such Senior Debt pursuant to the provisions of this Article 4 (equally and ratably with the holders of all indebtedness of the Company which by its express terms is subordinated to other indebtedness of the Company to substantially the same extent as the Debentures are subordinated and is entitled to like rights of subrogation) to the rights of the holders of Senior Debt to receive payments or distributions of cash, property or securities of the Company applicable to the Senior Debt until the principal, premium, if any, and interest (including Liquidated Damages, if any) on the Debentures shall be paid in full, and, for the purposes of such subrogation, no payments or distributions to the holders of the Senior Debt of any cash, property or securities to which the holders of the Debentures or the Trustee would

be entitled except for the provisions of this Article 4, and no payment over pursuant to the provisions of this Article 4, to or for the benefit of the holders of Senior Debt by holders of the Debentures or the Trustee, shall, as among the Company, its creditors other than holders of Senior Debt, and the holders of the Debentures, be deemed to be a payment by the Company to or on account of the Senior Debt, and no payments or distributions of cash, property or securities to or for the benefit of the holders of the Debentures pursuant to the subrogation provisions of this Article 4, which would otherwise have been paid to the holders of Senior Debt, shall be deemed to be a payment by the Company to or for the account of the Debentures. It is understood that the provisions of this Article 4 are and are intended solely for the purposes of defining the relative rights of the holders of the Debentures, on the one hand, and the holders of the Senior Debt, on the other hand.

Nothing contained in this Article 4 or elsewhere in this Indenture or in the Debentures is intended to or shall impair, as among the Company, its creditors other than the holders of Senior Debt, and the holders of the Debentures, the obligation of the Company, which is absolute and unconditional, to pay to the holders of the Debentures the principal of, premium, if any, and interest (including Liquidated Damages, if any) on the Debentures as and when the same shall become due and payable in accordance with their terms, or is intended to or shall affect the relative rights of the holders of the Debentures and creditors of the Company other than the holders of the Senior Debt, nor shall anything herein or therein prevent the Trustee or the holder of any Debenture from exercising all remedies otherwise permitted by applicable law upon default under this Indenture, subject to the rights, if any, under this Article 4 of the holders of Senior Debt in respect of cash, property or securities of the Company received upon the exercise of any such remedy.

Upon any payment or distribution of assets of the Company referred to in this Article 4, the Trustee, subject to the provisions of Section 8.01, and the holders of the Debentures shall be entitled to rely upon any order or decree made by any court of competent jurisdiction in which such bankruptcy, dissolution, winding up, liquidation or reorganization proceedings are pending, or a certificate of the receiver, trustee in bankruptcy, liquidating trustee, agent or other Person making such payment or distribution, delivered to the Trustee or to the holders of the Debentures, for the purpose of ascertaining the Persons entitled to participate in such distribution, the holders of the Senior Debt and other indebtedness of the Company, the amount thereof or payable thereon and all other facts pertinent thereto or to this Article 4.

Section 4.04 Authorization to Effect Subordination. Each holder of a Debenture by the holder’s acceptance thereof authorizes and directs the Trustee on the holder’s behalf to take such action as may be necessary or appropriate to effectuate the subordination as provided in this Article 4 and appoints the Trustee to act as the holder’s attorney-in-fact for any and all such purposes. If the Trustee does not file a proper proof of claim or proof of debt in the form required in any proceeding referred to in the third paragraph of Section 7.02 hereof at least thirty (30) days before the expiration of the time to file such claim, the holders of any Senior Debt or their Representatives are hereby authorized to file an appropriate claim for and on behalf of the holders of the Debentures.

Section 4.05 Notice to Trustee. The Company shall give prompt written notice in the form of an Officers’ Certificate to a Responsible Officer of the Trustee and to any paying agent of any fact known to the Company that would prohibit the making of any payment of monies to or by the Trustee or any paying agent in respect of the Debentures pursuant to the provisions of this Article 4. Notwithstanding the provisions of this Article 4 or any other provision of this Indenture, the Trustee shall not be charged with knowledge of the existence of any facts that would prohibit the making of any payment of monies to or by the Trustee in respect of the Debentures pursuant to the provisions of this Article 4, unless and until a Responsible Officer of the Trustee shall have received written notice thereof at the Corporate Trust Office from the Company (in the form of an Officers’ Certificate) or a Representative or a holder or holders of Senior Debt, and before the receipt of any such written notice, the Trustee, subject to the provisions of Section 8.01, shall be entitled in all respects to assume that no such facts exist; provided, however, that if on a date not less than one Business Day prior to the date upon which by the terms hereof any such monies may become payable for any purpose (including, without limitation, the payment of the principal of, or premium, if any, or interest (including Liquidated Damages, if any) on any Debenture) the Trustee shall not have received, with respect to such monies, the notice provided for in this Section 4.05, then, anything herein contained to the contrary notwithstanding, the Trustee shall have full power and authority to apply monies received to the purpose for which they were received, and shall not be affected by any notice to the contrary that may be received by it on or after such prior date.

Notwithstanding anything in this Article 4 to the contrary, nothing shall prevent any payment by the Trustee to the Debentureholders of monies deposited with it pursuant to Section 13.01, if a Responsible Officer of the Trustee shall not have received written notice at the Corporate Trust Office on or before one Business Day prior to the date such payment is due that such payment is not permitted under Section 4.01 or 4.02.

The Trustee, subject to the provisions of Section 8.01, shall be entitled to rely on the delivery to it of a written notice by a Representative or a person representing himself to be a holder of Senior Debt (or a trustee on behalf of such holder) to establish that such notice has been given by a Representative or a holder of Senior Debt or a trustee on behalf of any such holder or holders. The Trustee shall not be required to make any payment or distribution to or on behalf of a holder of Senior Debt pursuant to this Article 4 unless it has received satisfactory evidence as to the amount of Senior Debt held by such Person, the extent to which such Person is entitled to participate in such payment or distribution and any other facts pertinent to the rights of such Person under this Article 4.

Section 4.06 Trustee’s Relation to Senior Debt. The Trustee, in its individual capacity, shall be entitled to all the rights set forth in this Article 4 in respect of any Senior Debt at any time held by it, to the same extent as any other holder of Senior Debt, and nothing in Section 8.13 or elsewhere in this Indenture shall deprive the Trustee of any of its rights as such holder.

With respect to the holders of Senior Debt, the Trustee undertakes to perform or to observe only such of its covenants and obligations as are specifically set forth in this Article 4, and no implied covenants or obligations with respect to the holders of Senior Debt shall be read into this Indenture against the Trustee. The Trustee shall not be deemed to owe any fiduciary duty to the holders of Senior Debt and, subject to the provisions of Section 8.01, the Trustee shall not be liable to any holder of Senior Debt (i) for any failure to make any payments or distributions to such holder or (ii) if it shall pay over or deliver to holders of Debentures, the Company or any other Person money in compliance with this Article 4.

Section 4.07 No Impairment of Subordination. No right of any present or future holder of any Senior Debt to enforce subordination as herein provided shall at any time in any way be prejudiced or impaired by any act or failure to act on the part of the Company or by any act or failure to act, in good faith, by any such holder, or by any noncompliance by the Company with the terms, provisions and covenants of this Indenture, regardless of any knowledge thereof which any such holder may have or otherwise be charged with. Senior Debt may be created, renewed or extended and holders of Senior Debt may exercise any rights under any instrument creating or evidencing such Senior Debt, including, without limitation, any waiver of default thereunder, without any notice to or consent from the holders of the Debentures or the Trustee. No compromise, alteration, amendment, modification, extension, renewal or other change of, or waiver, consent or other action in respect of, any liability or obligation under or in respect of the Senior Debt or any terms or conditions of any instrument creating or evidencing such Senior Debt shall in any way alter or affect any of the provisions of this Article 4 or the subordination of the Debentures provided thereby.

Section 4.08 Certain Conversions Not Deemed Payment. For the purposes of this Article 4 only, (1) the issuance and delivery of junior securities upon conversion of Debentures in accordance with Article 15 shall not be deemed to constitute a payment or distribution on account of the principal of, premium, if any, or interest (including Liquidated Damages, if any) on Debentures or on account of the purchase or other acquisition of Debentures, and (2) the payment, issuance or delivery of cash (except in satisfaction of fractional shares pursuant to Section 15.03), property or securities (other than junior securities) upon conversion of a Debenture shall be deemed to constitute payment on account of the principal of, premium, if any, or interest (including Liquidated Damages, if any) on such Debenture. For the purposes of this Section 4.08, the term “junior securities” means (a) shares of any stock of any class of the Company or (b) securities of the Company that are subordinated in right of payment to all Senior Debt that may be outstanding at the time of issuance or delivery of such securities to substantially the same extent as, or to a greater extent than, the Debentures are so subordinated as provided in this Article 4. Nothing contained in this Article 4 or elsewhere in this Indenture or in the Debentures is intended to or shall impair, as among the Company, its creditors (other than holders of Senior Debt) and the Debentureholders, the right, which is absolute and unconditional, of the holder of any Debenture to convert such Debenture in accordance with Article 15.

Section 4.09 Article Applicable to Paying Agents. If at any time any paying agent other than the Trustee shall have been appointed by the Company and be then acting hereunder, the term “Trustee” as used in this Article 4 shall (unless the context otherwise requires) be construed as extending to and including such paying agent within its meaning as fully for all intents and purposes as if such paying agent were named in this Article 4 in addition to or in place of the Trustee; provided, however, that the first paragraph of Section 4.05 shall not apply to the Company or any Affiliate of the Company if it or such Affiliate acts as paying agent.

The Trustee shall not be responsible for the actions or inactions of any other paying agents (including the Company if acting as its own paying agent) and shall have no control of any funds held by such other paying agents.

Section 4.10 Senior Debt Entitled to Rely. The holders of Senior Debt (including, without limitation, Designated Senior Debt) shall have the right to rely upon this Article 4, and no amendment or modification of the provisions contained herein shall diminish the rights or such holders unless such holders shall have agreed in writing thereto.

Section 4.11 Reliance on Judicial Order or Certificate of Liquidating Agent. Upon any payment or distribution of assets of the Company referred to in this Article 4, the Trustee and the Debentureholders shall be entitled to rely upon any order or decree entered by any court of competent jurisdiction in which such insolvency, bankruptcy, receivership, liquidation, reorganization, dissolution, winding up or similar case or proceeding is pending, or a certificate of the trustee in bankruptcy, liquidating trustee, custodian, receiver, assignee for the benefit of creditors, agent or other Person making such payment or distribution, delivered to the Trustee or to the Debentureholders, for the purpose of ascertaining the Persons entitled to participate in such payment or distribution, the holders of Senior Debt and other indebtedness of the Company, the amount thereof or payable thereon, the amount or amounts paid or distributed thereon and all other facts pertinent thereto or to this Article 4.

Section 5.01 Payment of Principal, Premium and Interest. The Company covenants and agrees that it will duly and punctually pay or cause to be paid the principal of and premium, if any (including the redemption price upon redemption pursuant to Article 3), and interest (including Liquidated Damages, if any), on each of the Debentures at the places, at the respective times and in the manner provided herein and in the Debentures.

Section 5.02 Maintenance of Office or Agency. The Company will maintain an office or agency in the Borough of Manhattan, The City of New York, where the Debentures may be surrendered for registration of transfer or exchange or for presentation for payment or for conversion or redemption and where notices and demands to or upon the Company in respect of the Debentures 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 of agency of the Trustee in the Borough of Manhattan, The City of New York (which shall initially be located at c/o Computershare Trust Company of New York, Wall Street Plaza, 88 Pine Street, 19th floor, New York, NY 10005 Attn: Wilmington Trust (Mentor Graphics Corporation, Floating Rate Convertible Subordinated Debentures due 2023).

The Company may also from time to time designate co-registrars and one or more offices or agencies where the Debentures may be presented or surrendered for any or all such purposes and may from time to time rescind such designations. The Company will give prompt written notice of any such designation or rescission and of any change in the location of any such other office or agency.

The Company hereby initially designates the Trustee as paying agent, Debenture registrar, Custodian and conversion agent and each of the Corporate Trust Office and the office of agency of the Trustee in the Borough of Manhattan, The City of New York (which shall initially be located at c/o Computershare Trust Company of New York, Wall Street Plaza, 88 Pine Street, 19th floor, New York, NY 10005 Attn: Wilmington Trust (Mentor Graphics Corporation, Floating Rate Convertible Subordinated Debentures due 2023)), 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 Debenture registrar, the Trustee agrees to mail, or cause to be mailed, the notices set forth in Section 8.10(a) and the third paragraph of Section 8.11. If co-registrars have been appointed in accordance with this Section, the Trustee shall mail such notices only to the Company and the Debentureholders it can identify from its records.

Section 5.03 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 8.10, a Trustee, so that there shall at all times be a Trustee hereunder.

Section 5.04 Provisions As To Paying Agent. 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 5.04:

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

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

(3) 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, premium, if any, or interest on the Debentures, deposit with the paying agent a sum (in funds which are immediately available on the due date for such payment) sufficient to pay such principal, premium, if any, or interest, and (unless such paying agent is the Trustee) the Company will promptly notify the Trustee of any failure to take such action; provided, however, that if such deposit is made on the due date, such deposit shall be received by the paying agent by 10:00 a.m. New York City time, on such date.

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

(c) Anything in this Section 5.04 to the contrary notwithstanding, the Company may, at any time, for the purpose of obtaining a satisfaction and discharge of this Indenture, or for any other reason, pay or cause to be paid to the Trustee all sums held in trust by the Company or any paying agent hereunder as required by this Section 5.04, 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 5.04 to the contrary notwithstanding, the agreement to hold sums in trust as provided in this Section 5.04 is subject to Sections 13.03 and 13.04.

The Trustee shall not be responsible for the actions of any other paying agents (including the Company if acting as its own paying agent) and shall have no control of any funds held by such other paying agents.

Section 5.05 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 existence and rights (charter and statutory); provided, however, that the Company shall not be required to preserve any such right if the Company shall determine that the preservation thereof is no longer desirable in the conduct of the business of the Company and that the loss thereof is not disadvantageous in any material respect to the Debentureholders.

Section 5.06 Maintenance of Properties. The Company will cause all properties used or useful in the conduct of its business or the business of any Designated Subsidiary to be maintained and kept in good condition, repair and working order and supplied with all necessary equipment and will cause to be made all necessary repairs, renewals, replacements, betterments and improvements thereof, all as in the judgment of the Company may be necessary so that the business carried on in connection therewith may be properly and advantageously conducted at all times; provided, however, that nothing in this Section shall prevent the Company from discontinuing the operation or maintenance of any of such properties if such discontinuance is, in the judgment of the Company, desirable in the conduct of its business or the business of any subsidiary and not disadvantageous in any material respect to the Debentureholders.

Section 5.07 Payment of Taxes and Other Claims. The Company will pay or discharge, or cause to be paid or discharged, before the same may become delinquent, (i) all taxes, assessments and governmental charges levied or imposed upon the Company or any Designated Subsidiary or upon the income, profits or property of the Company or any Designated Subsidiary, (ii) all claims for labor, materials and supplies which, if unpaid, might by law become a lien or charge upon the property of the Company or any Designated Subsidiary and (iii) all stamps and other duties, if any, which may be imposed by the United States or any political subdivision thereof or therein in connection with the issuance, transfer, exchange or conversion of any Debentures or with respect to this Indenture; provided, however, that, in the case of clauses (i) and (ii), the Company shall not be required to pay or discharge or cause to be

paid or discharged any such tax, assessment, charge or claim (A) if the failure to do so will not, in the aggregate, have a material adverse impact on the Company, or (B) if the amount, applicability or validity is being contested in good faith by appropriate proceedings.

Section 5.08 Rule 144A Information Requirement. Within the period prior to the expiration of the holding period applicable to sales thereof under Rule 144(k) under the Securities Act (or any successor provision), the Company covenants and agrees that it shall, during any period in which it is not subject to Section 13 or 15(d) under the Exchange Act, make available to any holder or beneficial holder of Debentures or any Common Stock issued upon conversion thereof which continue to be Restricted Securities in connection with any sale thereof and any prospective purchaser of Debentures or such Common Stock designated by such holder or beneficial holder, the information required pursuant to Rule 144A(d)(4) under the Securities Act upon the request of any holder or beneficial holder of the Debentures or such Common Stock, and it will take such further action as any holder or beneficial holder of such Debentures or such Common Stock may reasonably request, all to the extent required from time to time to enable such holder or beneficial holder to sell its Debentures 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. Upon the request of any holder or any beneficial holder of the Debentures or such Common Stock, the Company will deliver to such holder a written statement as to whether it has complied with such requirements.

Section 5.09 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, premium, if any, or interest (including Liquidated Damages, if any) on the Debentures 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 5.10 Compliance Certificate. The Company shall deliver to the Trustee, within one hundred twenty (120) days after the end of each fiscal year of the Company (which is the end of the calendar year), a certificate signed by either the principal executive officer, principal financial officer or principal accounting officer of the Company, stating whether or not to the best knowledge of the signer thereof the Company is in default in the performance and observance of any of the terms, provisions and conditions of this Indenture (without regard to any period of grace or requirement of notice provided hereunder) and, if the Company shall be in default, specifying all such defaults and the nature and the status thereof of which the signer may have knowledge.

The Company will deliver to the Trustee, forthwith upon becoming aware of (i) any default in the performance or observance of any covenant, agreement or condition contained in this Indenture, or (ii) any Event of Default, an Officers’ Certificate specifying with particularity such default or Event of Default and further stating what action the Company has taken, is taking or proposes to take with respect thereto.

Any notice required to be given under this Section 5.10 or Section 4.05 shall be delivered to a Responsible Officer of the Trustee at its Corporate Trust Office.

Section 6.01 Debentureholders’ Lists. The Company covenants and agrees that it will furnish or cause to be furnished to the Trustee, quarterly, not more than fifteen (15) days after each January 21, April 21, July 21 and October 21 in each year beginning with October 21, 2003, 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 holders of Debentures 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 by the Company to the Trustee so long as the Trustee is acting as the sole Debenture registrar.

(a) The Trustee shall preserve, in as current a form as is reasonably practicable, all information as to the names and addresses of the holders of Debentures contained in the most recent list furnished to it as provided in Section 6.01 or maintained by the Trustee in its capacity as Debenture registrar or co-registrar in respect of the Debentures, if so acting. The Trustee may destroy any list furnished to it as provided in Section 6.01 upon receipt of a new list so furnished.

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

(c) Every Debentureholder, 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 holders of Debentures made pursuant to the Trust Indenture Act.

(a) Within sixty (60) days after August 6 of each year commencing with the year 2004, the Trustee shall transmit to holders of Debentures such reports dated as of August 6 of the year in which such reports are made 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.

(b) A copy of such report shall, at the time of such transmission to holders of Debentures, be filed by the Trustee with each stock exchange and automated quotation system upon which the Debentures are listed and with the Company. The Company will promptly notify the Trustee in writing when the Debentures are listed on any stock exchange or automated quotation system or delisted therefrom.

Section 6.04 Reports by Company. The Company shall file with the Trustee (and the Commission if at any time after the Indenture becomes qualified under the Trust Indenture Act), and transmit to holders of Debentures, 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, whether or not the Debentures are governed by such Act; provided, however, 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 filed with the Trustee within fifteen (15) days after the same is so required to be filed with the Commission. 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 rely exclusively on Officers’ Certificates).

Section 7.01 Events of Default. In case one or more of the following Events of Default (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) shall have occurred and be continuing:

(a) default in the payment of any installment of interest (including Liquidated Damages, if any) upon any of the Debentures as and when the same shall become due and payable, and continuance of such default for a period of thirty (30) days, whether or not such payment is permitted under Article 4 hereof; or

(b) default in the payment of the principal of or premium, if any, on any of the Debentures as and when the same shall become due and payable either at maturity or in connection with any redemption or repurchase pursuant to Article 3, by acceleration or otherwise, whether or not such payment is permitted under Article 4 hereof; or

(c) failure on the part of the Company duly to observe or perform any other term, covenant or agreement on the part of the Company in the Debentures or in this Indenture (other than a covenant or agreement a default in whose performance or whose breach is elsewhere in this Section 7.01 specifically dealt with) for a period of sixty (60) days after the date on which written notice of such failure, requiring the Company to remedy the same, shall have been given to the Company by the Trustee, or the Company and a Responsible Officer of the Trustee by the holders of at least twenty-five percent (25%) in aggregate principal amount of the Debentures at the time outstanding determined in accordance with Section 9.04; or

(d) a failure to pay when due at maturity or a default that results in the acceleration of maturity of any Indebtedness of the Company and/or of Designated Subsidiaries in an aggregate amount of $30 million or more, unless the acceleration is rescinded, stayed or annulled within thirty (30) days after written notice of default is given to the Company by the Trustee or to the Company and the Trustee by the holders of at lease twenty five percent (25%) in aggregate principal amount of the Debentures at the time outstanding determined in accordance with Section 9.04; or

(e) the commencement of a voluntary case or other proceeding seeking liquidation, reorganization or other relief with respect to the Company or a Designated Subsidiary 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 of a Designated Subsidiary or any substantial part of the property of the Company or a Designated Subsidiary, 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 the Company or a Designated Subsidiary, or shall make a general assignment for the benefit of creditors, or shall fail generally to pay its debts as they become due; or

(f) an involuntary case or other proceeding shall be commenced against the Company or a Designated Subsidiary seeking liquidation, reorganization or other relief with respect to the Company or a Designated Subsidiary 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 a Designated Subsidiary or any substantial part of the property of the Company or a Designated Subsidiary, and such involuntary case or other proceeding shall remain undismissed and unstayed for a period of ninety (90) consecutive days;

then, and in each and every such case (other than an Event of Default specified in Section 7.01(e) or (f)), unless the principal of all of the Debentures shall have already become due and payable, either the Trustee or the holders of not less than twenty-five percent (25%) in aggregate principal amount of the Debentures then outstanding hereunder determined in accordance with Section 9.04, by notice in writing to the Company (and to the Trustee if given by Debentureholders), may declare the principal of and premium, if any, on all the Debentures and the interest accrued thereon (including Liquidated Damages, if any) 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 Debentures contained to the contrary notwithstanding. If an Event of Default specified in Section 7.01(e) or (f) occurs, the principal of all the Debentures and the interest accrued thereon shall (including Liquidated Damages, if any) be immediately and automatically due and payable without necessity of further action. This provision, however, is subject to the conditions that if, at any time after the principal of the Debentures 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 all matured installments of interest upon

(including Liquidated Damages, if any) all Debentures and the principal of and premium, if any, on any and all Debentures which shall have become due otherwise than by acceleration (with interest on overdue installments of interest (including Liquidated Damages, if any) (to the extent that payment of such interest is enforceable under applicable law) and on such principal and premium, if any, at the rate borne by the Debentures, to the date of such payment or deposit) and amounts due to the Trustee pursuant to Section 8.06, and if any and all defaults under this Indenture, other than the nonpayment of principal of and premium, if any, and accrued interest on (including Liquidated Damages, if any) Debentures which shall have become due by acceleration, shall have been cured or waived pursuant to Section 7.07, then and in every such case the holders of a majority in aggregate principal amount of the Debentures then outstanding, by written notice to the Company and to the Trustee, may waive all defaults or Events of Default and rescind and annul such declaration and its consequences; 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 a Responsible Officer of the Trustee, promptly upon becoming aware thereof, of any Event of Default.

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 holders of Debentures, and the Trustee shall be restored respectively to their several positions and rights hereunder, and all rights, remedies and powers of the Company, the holders of Debentures, and the Trustee shall continue as though no such proceeding had been taken.

Section 7.02 Payments of Debentures on Default; Suit Therefor. The Company covenants that (a) in case default shall be made in the payment of any installment of interest upon (including Liquidated Damages, if any) any of the Debentures as and when the same shall become due and payable, and such default shall have continued for a period of thirty (30) days, or (b) in case default shall be made in the payment of the principal of or premium, if any, on any of the Debentures as and when the same shall have become due and payable, whether at maturity of the Debentures or in connection with any redemption, by or under this Indenture declaration or otherwise, then, upon demand of the Trustee, the Company will pay to the Trustee, for the benefit of the holders of the Debentures, the whole amount that then shall have become due and payable on all such Debentures for principal and premium, if any, or interest (including Liquidated Damages, if any), as the case may be, with interest upon the overdue principal and premium, if any, and (to the extent that payment of such interest is enforceable under applicable law) upon the overdue installments of interest (including Liquidated Damages, if any) at the rate borne by the Debentures, and, in addition thereto, such further amount as shall be sufficient to cover the costs and expenses of collection, including reasonable compensation to the Trustee, its agents, attorneys and counsel, and all other amounts due the Trustee under Section 8.06. Until such demand by the Trustee, the Company may pay the principal of and premium, if any, and interest on (including Liquidated Damages, if any) the Debentures to the registered holders, whether or not the Debentures are overdue.

In case the Company shall fail forthwith to pay such amounts upon such demand, the Trustee, in its own name and as trustee of an express trust, 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, and may prosecute any such action or proceeding to judgment or final decree, and may enforce any such judgment or final decree against the Company or any other obligor on the Debentures and collect in the manner provided by law out of the property of the Company or any other obligor on the Debentures 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 Debentures 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 Debentures, or to the creditors or property of the Company or such other obligor, the Trustee, irrespective of whether the principal of the Debentures 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 7.02, shall be entitled and empowered, by intervention in such proceedings or otherwise, to file and prove a claim or claims for the whole amount of principal, premium, if any, and interest (including Liquidated Damages, if any) owing and unpaid in respect of the Debentures, and, in case of any judicial proceedings, to file such proofs of claim and other papers or documents as may be necessary or advisable in order to have the claims of the Trustee and of the Debentureholders allowed in such judicial proceedings relative to the Company or any other obligor on the Debentures, 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 8.06, and any receiver, assignee or trustee in bankruptcy or reorganization, liquidator, custodian or similar official is hereby authorized by each of the Debentureholders to make such payments to the Trustee, and, in the event that the Trustee shall consent to the making of such payments directly to the Debentureholders, to pay to the Trustee any amount due it for reasonable compensation, expenses, advances and disbursements, including reasonable counsel fees 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 Debentures may be entitled to receive in such proceedings, whether in liquidation or under any plan of reorganization or arrangement or otherwise.

All rights of action and of asserting claims under this Indenture, or under any of the Debentures, may be enforced by the Trustee without the possession of any of the Debentures, 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 agent and counsel, be for the ratable benefit of the holders of the Debentures.

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 Debentures, and it shall not be necessary to make any holders of the Debentures parties to any such proceedings.

Section 7.03 Application of Monies Collected by Trustee. Any monies collected by the Trustee pursuant to this Article 7 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 Debentures, and stamping thereon the payment, if only partially paid, and upon surrender thereof, if fully paid:

SECOND: Subject to the provisions of Article 4, in case the principal of the outstanding Debentures shall not have become due and be unpaid, to the payment of interest on (including Liquidated Damages, if any) the Debentures 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 (including Liquidated Damages, if any) at the rate borne by the Debentures, such payments to be made ratably to the Persons entitled thereto;

THIRD: Subject to the provisions of Article 4, in case the principal of the outstanding Debentures shall have become due, by declaration or otherwise, and be unpaid to the payment of the whole amount then owing and unpaid upon the Debentures for principal and premium, if any, and interest (including Liquidated Damages, if any), with interest on the overdue principal and premium, if any, and (to the extent that such interest has been collected by the Trustee) upon overdue installments of interest (including Liquidated Damages, if any) at the rate borne by the Debentures, and in case such monies shall be insufficient to pay in full the whole amounts so due and unpaid upon the Debentures, then to the payment of such principal and premium, if any, and interest (including Liquidated Damages, if any) without preference or priority of principal and premium, if any, over interest (including Liquidated Damages, if any), or of interest (including Liquidated Damages, if any) over principal and premium, if any, or of any installment of interest over any other installment of interest, or of any Debenture over any other Debenture, ratably to the aggregate of such principal and premium, if any, and accrued and unpaid interest; and

FOURTH: Subject to the provisions of Article 4, to the payment of the remainder, if any, to the Company or any other Person lawfully entitled thereto.

Section 7.04 Proceedings by Debentureholders. No holder of any Debenture shall have any right by virtue of or by reference to 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 Debentures 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 reasonable indemnity as it may require against the costs, expenses and liabilities 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 inconsistent with such written request shall have been given to the Trustee pursuant to Section 7.07; it being understood and intended, and being expressly covenanted by the taker and holder of every Debenture with every other taker and holder and the Trustee, that no one or more holders of Debentures shall have any right in any manner whatsoever by virtue of or by reference to any provision of this Indenture to affect, disturb or prejudice the rights of any other holder of Debentures, 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 holders of Debentures (except as otherwise provided herein). For the protection and enforcement of this Section 7.04, each and every Debentureholders 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 Debenture, the right of any holder of any Debenture to receive payment of the principal of and premium, if any (including the redemption price upon redemption pursuant to Article 3), and accrued interest on (including Liquidated Damages, if any) such Debenture, on or after the respective due dates expressed in such Debenture or in the event of redemption, 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 holder.

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

Section 7.05 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 7.06 Remedies Cumulative and Continuing. Except as provided in Section 2.06, all powers and remedies given by this Article 7 to the Trustee or to the Debentureholders 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 Debentures, 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 Debentures to exercise any right or power accruing upon any default or Event of Default occurring and continuing as aforesaid shall impair any such right or power, or shall be construed to be a waiver of any such default or any acquiescence therein, and, subject to the provisions of Section 7.04, every power and remedy given by this Article 7 or by law to the Trustee or to the Debentureholders may be exercised from time to time, and as often as shall be deemed expedient, by the Trustee or by the Debentureholders.

Section 7.07 Direction of Proceedings and Waiver of Defaults by Majority of Debentureholders. The holders of a majority (more than fifty percent) in aggregate principal amount of the Debentures at the time outstanding determined in accordance with Section 9.04 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; provided, however, that (a) such direction shall be in writing, (b) such direction shall not be in conflict with any rule of law or with this Indenture, (c) the Trustee may take any other action which is not inconsistent with such direction and (d) the Trustee may decline to take any action that would benefit some Debentureholders to the detriment of other Debentureholders. The holders of a majority in aggregate principal amount of the Debentures at the time outstanding determined in accordance with Section 9.04 may, on behalf of the holders of all of the Debentures, waive any past default or Event of Default hereunder and its consequences except (i) a default in the payment of interest (including Liquidated Damages, if any) or premium, if any, on, or the principal of, the Debentures, (ii) a failure by the Company to convert any Debentures into Common Stock, (iii) a default in the payment of redemption price pursuant to Article 3 or (iv) a default in respect of a covenant or provisions hereof which under Article 11 cannot be modified or amended without the consent of the holders of each or all Debentures then outstanding or affected thereby. Upon any such waiver, the Company, the Trustee and the holders of the Debentures shall be restored to their former positions and rights hereunder, but no such waiver shall extend to any subsequent or other default or Event of Default or impair any right consequent thereon. Whenever any default or Event of Default hereunder shall have been waived as permitted by this Section 7.07, said default or Event of Default shall for all purposes of the Debentures and this Indenture be deemed to have been cured and to be not continuing, but no such waiver shall extend to any subsequent or other default or Event of Default or impair any right consequent thereon.

Section 7.08 Notice of Defaults. The Trustee shall, within ninety (90) days after a Responsible Officer of the Trustee has knowledge of the occurrence of a default, mail to all Debentureholders, as the names and addresses of such holders appear upon the Debenture register, notice of all defaults known to a Responsible Officer, unless such defaults shall have been cured or waived before the giving of such notice; provided, however, that except in the case of default in the payment of the principal of, or premium, if any, or interest (including Liquidated Damages, if any) on any of the Debentures, the Trustee shall be protected in withholding such notice if and so long as a trust committee of directors and/or Responsible Officers of the Trustee in good faith determines that the withholding of such notice is in the interests of the Debentureholders.

Section 7.09 Undertaking to Pay Costs. All parties to this Indenture agree, and each holder of any Debenture by such holder’s acceptance thereof shall be deemed to have agreed, that any court may, in its discretion, require, in any suit for the enforcement of any right or remedy under this Indenture, or in any suit against the Trustee for any action taken or omitted by it as Trustee, the filing by any party litigant in such suit of an undertaking to pay the costs of such suit and that such court may in its discretion assess reasonable costs, including reasonable attorneys’ fees and expenses, against any party litigant in such suit, having due regard to the merits and good faith of the claims or defenses made by such party litigant; provided, however, that the provisions of this Section 7.09 (to the extent permitted by law) shall not apply to any suit instituted by the Trustee, to any suit instituted by any Debentureholders, or group of

Debentureholders, holding in the aggregate more than ten percent in principal amount of the Debentures at the time outstanding determined in accordance with Section 9.04, or to any suit instituted by any Debentureholders for the enforcement of the payment of the principal of or premium, if any, or interest on any Debenture on or after the due date expressed in such Debenture or to any suit for the enforcement of the right to convert any Debenture in accordance with the provisions of Article 15.

Section 8.01 Duties and Responsibilities of Trustee. The Trustee, prior to the occurrence of an Event of Default and after the curing of all Events of Default which may have occurred, undertakes to perform such duties and only such duties as are specifically set forth in this Indenture. In case an Event of Default has occurred (which has not been cured or waived), the Trustee shall exercise such of the rights and powers vested in it by this Indenture, and use the same degree of care and skill in their exercise, as a prudent person would exercise or use under the circumstances in the conduct of his own affairs.

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

(a) prior to the occurrence of an Event of Default and after the curing or waiving of all Events of Default which may have occurred:

(1) the duties and obligations of the Trustee shall be determined solely by the express provisions of this Indenture and the Trust Indenture Act, and the Trustee shall not be liable except for the performance of such duties and obligations as are specifically set forth in this Indenture and no implied covenants or obligations shall be read into this Indenture and the Trust Indenture Act against the Trustee; and

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

(b) the Trustee shall not be liable for any error of judgment made in good faith by a Responsible Officer or Officers of the Trustee, unless the Trustee was negligent in ascertaining the pertinent facts;

(c) the Trustee shall not be liable with respect to any action taken or omitted to be taken by it in good faith in accordance with the written direction of the holders of not less than a majority in principal amount of the Debentures at the time outstanding determined as provided in Section 9.04 relating to the time, method and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred upon the Trustee, under this Indenture;

(d) whether or not therein provided, every provision of this Indenture relating to the conduct or affecting the liability of, or affording protection to, the Trustee shall be subject to the provisions of this Section 8.01;

(e) the Trustee shall not be liable in respect of any payment (as to the correctness of amount, entitlement to receive or any other matters relating to payment) or notice effected by the Company or any paying agent or any records maintained by any co-registrar with respect to the Debentures; and

(f) if any party fails to deliver a notice relating to an event the fact of which, pursuant to this Indenture, requires notice to be sent to the Trustee, the Trustee may conclusively rely on its failure to receive such notice as reason to act as if no such event occurred.

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

Section 8.02 Reliance on Documents, Opinions, Etc. Except as otherwise provided in Section 8.01:

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

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

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

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

(e) the Trustee shall not be bound to make any investigation into the facts or matters stated in any resolution, certificate, statement, instrument, opinion, report, notice, request, direction, consent, order, bond, debenture or other paper or document, but the Trustee, in its discretion, may make such further inquiry or investigation into such facts or matters as it may see fit, and, if the Trustee shall reasonably determine to make such further inquiry or investigation, it shall be entitled to examine the relevant books, records and premises of the Company, personally or by agent or attorney; and

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

Section 8.03 No Responsibility for Recitals, Etc. The recitals contained herein and in the Debentures (except in the Trustee’s certificate of authentication) shall be taken as the statements of the Company, and the Trustee assumes no responsibility for the correctness of the same. The Trustee makes no representations as to the validity or sufficiency of this Indenture or of the Debentures. The Trustee shall not be accountable for the use or application by the Company of any Debentures or the proceeds of any Debentures authenticated and delivered by the Trustee in conformity with the provisions of this Indenture.

Section 8.04 Trustee, Paying Agents, Conversion Agents or Registrar May Own Debentures. The Trustee, any paying agent, any conversion agent or Debenture registrar, in its individual or any other capacity, may become the owner or pledgee of Debentures with the same rights it would have if it were not Trustee, paying agent, conversion agent or Debenture registrar.

Section 8.05 Monies to Be Held in Trust. Subject to the provisions of Section 13.04 and Section 4.02, all monies received by the Trustee shall, until used or applied as herein provided, be held in trust for the purposes for which they were received. Money held by the Trustee in trust hereunder need not be segregated from other funds except to the extent required by law. The Trustee shall be under no liability for interest on any money received by it hereunder except as may be agreed in writing from time to time by the Company and the Trustee.

Section 8.06 Compensation and Expenses of Trustee. The Company covenants and agrees to pay to the Trustee from time to time, and the Trustee shall be entitled to, reasonable compensation for all services rendered by it hereunder in any capacity (which shall not be limited by any provision of law in regard to the compensation of a trustee of an express trust) as mutually agreed to from time to time in writing between the Company and the Trustee, and the Company will pay or reimburse the Trustee upon its request for all reasonable expenses, disbursements and advances reasonably incurred or made by the Trustee in accordance with any of the provisions of this Indenture (including the reasonable compensation and the expenses and disbursements of its counsel and of all Persons not regularly in its employ) except any such expense, disbursement or advance as may arise from its negligence, willful misconduct, recklessness or bad faith. The Company also covenants to indemnify the Trustee (or any officer, director or employee of the Trustee), in any capacity under this Indenture and its agents and any authenticating agent for, and to hold them harmless against, any and all loss, liability, claim or expense incurred without negligence, willful misconduct, recklessness or bad faith on the part of

the Trustee or such officers, directors, employees and agent or authenticating agent, as the case may be, and arising out of or in connection with the acceptance or administration of this trust or in any other capacity hereunder, including the reasonable costs and expenses of defending themselves against any claim of liability in the premises. The obligations of the Company under this Section 8.06 to compensate or indemnify the Trustee and to pay or reimburse the Trustee for expenses, disbursements and advances shall be secured by a lien prior to that of the Debentures upon all property and funds held or collected by the Trustee as such, except funds held in trust for the benefit of the holders of particular Debentures. The obligation of the Company under this Section shall survive the satisfaction and discharge of this Indenture.

When the Trustee and its agents and any authenticating agent incur expenses or render services after an Event of Default specified in Section 7.01(e) or (f) with respect to the Company occurs, the expenses and the compensation for the services are intended to constitute expenses of administration under any bankruptcy, insolvency or similar laws.

Section 8.07 Officers’ Certificate as Evidence. Except as otherwise provided in Section 8.01, whenever in the administration of the provisions of this Indenture the Trustee shall deem it necessary or desirable that a matter be proved or established prior to taking or omitting any action hereunder, such matter (unless other evidence in respect thereof be herein specifically prescribed) may, in the absence of negligence or willful misconduct on the part of the Trustee, be deemed to be conclusively proved and established by an Officers’ Certificate delivered to the Trustee.

Section 8.08 Conflicting Interests of Trustee. If the Trustee has or shall acquire a conflicting interest within the meaning of the Trust Indenture Act, the Trustee shall either eliminate such interest or resign, to the extent and in the manner provided by, and subject to the provisions of, the Trust Indenture Act and this Indenture.

Section 8.09 Eligibility of Trustee. There shall at all times be a Trustee hereunder which shall be a Person that is eligible pursuant to the Trust Indenture Act to act as such and has a combined capital and surplus of at least $50,000,000 (or if such Person is a member of a bank holding company system, its bank holding company shall have a combined capital and surplus of at least $50,000,000). If such Person publishes reports of condition at least annually, pursuant to law or to the requirements of any supervising or examining authority, then for the purposes of this Section, the combined capital and surplus of such Person shall be deemed to be its combined capital and surplus as set forth in its most recent report of condition so published. If at any time the Trustee shall cease to be eligible in accordance with the provisions of this Section 8.09, it shall resign immediately in the manner and with the effect hereinafter specified in this Article.

(a) The Trustee may at any time resign by giving written notice of such resignation to the Company and to the holders of Debentures. Upon receiving such notice of resignation, the Company shall promptly appoint a successor trustee by written instrument, in duplicate, executed by order of the Board of Directors, one copy of which instrument shall be delivered to the resigning Trustee and one copy to the successor trustee. If no successor trustee shall have been so appointed and have accepted appointment sixty (60) days after the mailing of

such notice of resignation to the Debentureholders, the resigning Trustee may, upon ten (10) business days’ notice to the Company and the Debentureholders, appoint a successor identified in such notice or may petition, at the expense of the Company, any court of competent jurisdiction for the appointment or a successor trustee, or, if any Debentureholder who has been a bona fide holder of a Debenture or Debentures for at least six (6) months may, subject to the provisions of Section 7.09, on behalf of himself and all others similarly situated, petition any such court for the appointment of a successor trustee. Such court may thereupon, after such notice, if any, as it may deem proper and prescribe, appoint a successor trustee.

(1) the Trustee shall fail to comply with Section 8.08 after written request therefor by the Company or by any Debentureholders who has been a bona fide holder of a Debenture or Debentures for at least six (6) months; or

(2) the Trustee shall cease to be eligible in accordance with the provisions of Section 8.09 and shall fail to resign after written request therefor by the Company or by any such Debentureholders; or

(3) the Trustee shall become incapable of acting, or shall be adjudged a bankrupt or insolvent, or a receiver of the Trustee or of its property shall be appointed, or any public officer shall take charge or control of the Trustee or of its property or affairs for the purpose of rehabilitation, conservation or liquidation;

then, in any such case, the Company may remove the Trustee and appoint a successor trustee by written instrument, in duplicate, executed by order of the Board of Directors, one copy of which instrument shall be delivered to the Trustee so removed and one copy to the successor trustee, or, subject to the provisions of Section 7.09, any Debentureholders who has been a bona fide holder of a Debenture or Debentures for at least six (6) months may, on behalf of himself and all others similarly situated, petition any court of competent jurisdiction for the removal of the Trustee and the appointment of a successor trustee; provided, however, that if no successor Trustee shall have been appointed and have accepted appointment sixty (60) days after either the Company or the Debentureholders has removed the Trustee, the Trustee so removed may petition any court of competent jurisdiction for an appointment of a successor trustee. Such court may thereupon, after such notice, if any, as it may deem proper and prescribe, remove the Trustee and appoint a successor trustee.

(c) The holders of a majority in aggregate principal amount of the Debentures at the time outstanding may at any time remove the Trustee and nominate a successor trustee which shall be deemed appointed as successor trustee unless, within ten (10) days after notice to the Company of such nomination, the Company objects thereto, in which case the Trustee so removed or any Debentureholders, or if such Trustee so removed or any Debentureholders fails to act, the Company, upon the terms and conditions and otherwise as in Section 8.10(a) provided, may petition any court of competent jurisdiction for an appointment of a successor trustee.

(d) Any resignation or removal of the Trustee and appointment of a successor trustee pursuant to any of the provisions of this Section 8.10 shall become effective upon acceptance of appointment by the successor trustee as provided in Section 8.11.

Section 8.11 Acceptance by Successor Trustee. Any successor trustee appointed as provided in Section 8.10 shall execute, acknowledge and deliver to the Company and to its predecessor trustee an instrument accepting such appointment hereunder, and thereupon the resignation or removal of the predecessor trustee shall become effective and such successor trustee, without any further act, deed or conveyance, shall become vested with all the rights, powers, duties and obligations of its predecessor hereunder, with like effect as if originally named as trustee herein; but, nevertheless, on the written request of the Company or of the successor trustee, the trustee ceasing to act shall, upon payment of any amount then due it pursuant to the provisions of Section 8.06, execute and deliver an instrument transferring to such successor trustee all the rights and powers of the trustee so ceasing to act. Upon request of any such successor trustee, the Company shall execute any and all instruments in writing for more fully and certainly vesting in and confirming to such successor trustee all such rights and powers. Any trustee ceasing to act shall, nevertheless, retain a lien upon all property and funds held or collected by such trustee as such, except for funds held in trust for the benefit of holders of particular Debentures, to secure any amounts then due it pursuant to the provisions of Section 8.06.

No successor trustee shall accept appointment as provided in this Section 8.11 unless, at the time of such acceptance, such successor trustee shall be qualified under the provisions of Section 8.08 and be eligible under the provisions of Section 8.09.

Upon acceptance of appointment by a successor trustee as provided in this Section 8.11, the Company (or the former trustee, at the written direction of the Company) shall mail or cause to be mailed notice of the succession of such trustee hereunder to the holders of Debentures at their addresses as they shall appear on the Debenture register. If the Company fails to mail such notice within ten (10) days after acceptance of appointment by the successor trustee, the successor trustee shall cause such notice to be mailed at the expense of the Company.

Section 8.12 Succession by Merger, Etc. Any corporation into which the Trustee may be merged or converted or with which it may be consolidated, or any corporation resulting from any merger, conversion or consolidation to which the Trustee shall be a party, or any corporation succeeding to all or substantially all of the corporate trust business of the Trustee (including any trust created by this Indenture), shall be the successor to the Trustee hereunder without the execution or filing of any paper or any further act on the part of any of the parties hereto, provided that in the case of any corporation succeeding to all or substantially all of the corporate trust business of the Trustee, such corporation shall be qualified under the provisions of Section 8.08 and eligible under the provisions of Section 8.09.

In case at the time such successor to the Trustee shall succeed to the trusts created by this Indenture, any of the Debentures shall have been authenticated but not delivered, any such successor to the Trustee may adopt the certificate of authentication of any predecessor trustee or authenticating agent appointed by such predecessor trustee, and deliver such Debentures so authenticated; and in case at that time any of the Debentures shall not have been authenticated,

any successor to the Trustee or any authenticating agent appointed by such successor trustee may authenticate such Debentures in the name of the successor trustee; and in all such cases such certificates shall have the full force that is provided in the Debentures or in this Indenture; provided, however, that the right to adopt the certificate of authentication of any predecessor Trustee or authenticate Debentures in the name of any predecessor Trustee shall apply only to its successor or successors by merger, conversion or consolidation.

Section 8.13 Preferential Collection of Claims. If and when the Trustee shall be or become a creditor of the Company (or any other obligor upon the Debentures), the Trustee shall be subject to the provisions of the Trust Indenture Act regarding the collection of the claims against the Company (or any such other obligor).

Section 8.14 Trustee’s Application for Instructions from the Company. Any application by the Trustee for written instructions from the Company (other than with regard to any action proposed to be taken or omitted to be taken by the Trustee that affects the rights of the holders of the Debentures or holders of Senior Debt under this Indenture, including, without limitation, under Article 4 hereof) may, at the option of the Trustee, set forth in writing any action proposed to be taken or omitted by the Trustee under this Indenture and the date on and/or after which such action shall be taken or such omission shall be effective. The Trustee shall not be liable for any action taken by, or omission of, the Trustee in accordance with a proposal included in such application on or after the date specified in such application (which date shall not be less than three (3) Business Days after the date any officer of the Company actually receives such application, unless any such officer shall have consented in writing to any earlier date) unless prior to taking any such action (or the effective date in the case of an omission), the Trustee shall have received written instructions in response to such application specifying the action to be taken or omitted.

Section 9.01 Action by Debentureholders. Whenever in this Indenture it is provided that the holders of a specified percentage in aggregate principal amount of the Debentures may take any action (including the making of any demand or request, the giving of any notice, consent or waiver or the taking of any other action), the fact that at the time of taking any such action, the holders of such specified percentage have joined therein may be evidenced (a) by any instrument or any number of instruments of similar tenor executed by Debentureholders in person or by agent or proxy appointed in writing, or (b) by the record of the holders of Debentures voting in favor thereof at any meeting of Debentureholders duly called and held in accordance with the provisions of Article 10, or (c) by a combination of such instrument or instruments and any such record of such a meeting of Debentureholders. Whenever the Company or the Trustee solicits the taking of any action by the holders of the Debentures, the Company or the Trustee may fix in advance of such solicitation, a date as the record date for determining holders entitled to take such action. The record date shall be not more than fifteen (15) days prior to the date of commencement of solicitation of such action.

Section 9.02 Proof of Execution by Debentureholders. Subject to the provisions of Sections 8.01, 8.02 and 10.05, proof of the execution of any instrument by a Debentureholders or its agent or proxy shall be sufficient if made in accordance with such reasonable rules and regulations as may be prescribed by the Trustee or in such manner as shall be satisfactory to the Trustee. The holding of Debentures shall be proved by the registry of such Debentures or by a certificate of the Debenture registrar.

The record of any Debentureholders’ meeting shall be proved in the manner provided in Section 10.06.

Section 9.03 Who Are Deemed Absolute Owners. The Company, the Trustee, any paying agent, any conversion agent and any Debenture registrar may deem the Person in whose name such Debenture shall be registered upon the Debenture register to be, and may treat it as, the absolute owner of such Debenture (whether or not such Debenture shall be overdue and notwithstanding any notation of ownership or other writing thereon made by any Person other than the Company or any Debenture registrar) for the purpose of receiving payment of or on account of the principal of, premium, if any, and interest on such Debenture, for conversion of such Debenture and for all other purposes; and neither the Company nor the Trustee nor any paying agent nor any conversion agent nor any Debenture registrar shall be affected by any notice to the contrary. All such payments so made to any holder for the time being, or upon his order, shall be valid, and, to the extent of the sum or sums so paid, effectual to satisfy and discharge the liability for monies payable upon any such Debenture.

Section 9.04 Company-owned Debentures Disregarded. In determining whether the holders of the requisite aggregate principal amount of Debentures have concurred in any direction, consent, waiver or other action under this Indenture, Debentures which are owned by the Company or any other obligor on the Debentures or any Affiliate of the Company or any other obligor on the Debentures shall be disregarded and deemed not to be outstanding for the purpose of any such determination; provided, however, that, for the purposes of determining whether the Trustee shall be protected in relying on any such direction, consent, waiver or other action, only Debentures which a Responsible Officer knows are so owned shall be so disregarded. Debentures so owned which have been pledged in good faith may be regarded as outstanding for the purposes of this Section 9.04 if the pledgee shall establish to the satisfaction of the Trustee the pledgee’s right to vote such Debentures and that the pledgee is not the Company, any other obligor on the Debentures or any Affiliate of the Company or any such other obligor. In the case of a dispute as to such right, any decision by the Trustee taken upon the advice of counsel shall be full protection to the Trustee. Upon request of the Trustee, the Company shall furnish to the Trustee promptly an Officers’ Certificate listing and identifying all Debentures, if any, known by the Company to be owned or held by or for the account of any of the above described Persons, and, subject to Section 8.01, the Trustee shall be entitled to accept such Officers’ Certificate as conclusive evidence of the facts therein set forth and of the fact that all Debentures not listed therein are outstanding for the purpose of any such determination.

Section 9.05 Revocation of Consents; Future Holders Bound. At any time prior to (but not after) the evidencing to the Trustee, as provided in Section 9.01, of the taking of any action by the holders of the percentage in aggregate principal amount of the Debentures specified in this Indenture in connection with such action, any holder of a Debenture which is shown by the evidence to be included in the Debentures the holders of which have consented to such action may, by filing written notice with the Trustee at its Corporate Trust Office and upon proof of

holding as provided in Section 9.02, revoke such action so far as concerns such Debenture. Except as aforesaid, any such action taken by the holder of any Debenture shall be conclusive and binding upon such holder and upon all future holders and owners of such Debenture and of any Debentures issued in exchange or substitution therefor, irrespective of whether any notation in regard thereto is made upon such Debenture or any Debenture issued in exchange or substitution therefor.

Section 10.01 Purpose of Meetings. A meeting of Debentureholders may be called at any time and from time to time pursuant to the provisions of this Article 10 for any of the following purposes:

(1) to give any notice to the Company or to the Trustee or to give any directions to the Trustee permitted under this Indenture, or to consent to the waiving of any default or Event of Default hereunder and its consequences, or to take any other action authorized to be taken by Debentureholders pursuant to any of the provisions of Article 7;

(2) to remove the Trustee and nominate a successor trustee pursuant to the provisions of Article 8;

(3) to consent to the execution of an indenture or indentures supplemental hereto pursuant to the provisions of Section 11.02; or

(4) to take any other action authorized to be taken by or on behalf of the holders of any specified aggregate principal amount of the Debentures under any other provision of this Indenture or under applicable law.

Section 10.02 Call of Meetings by Trustee. The Trustee may at any time call a meeting of Debentureholders to take any action specified in Section 10.01, to be held at such time and at such place as the Trustee shall determine. Notice of every meeting of the Debentureholders, setting forth the time and the place of such meeting and in general terms the action proposed to be taken at such meeting and the establishment of any record date pursuant to Section 9.01, shall be mailed to holders of Debentures at their addresses as they shall appear on the Debenture register. Such notice shall also be mailed to the Company. Such notices shall be mailed not less than twenty (20) nor more than ninety (90) days prior to the date fixed for the meeting.

Any meeting of Debentureholders shall be valid without notice if the holders of all Debentures then outstanding are present in person or by proxy or if notice is waived before or after the meeting by the holders of all Debentures outstanding, and if the Company and the Trustee are either present by duly authorized representatives or have, before or after the meeting, waived notice.

Section 10.03 Call of Meetings by Company or Debentureholders. In case at any time the Company, pursuant to a resolution of its Board of Directors, or the holders of at least ten percent (10%) in aggregate principal amount of the Debentures then outstanding, shall have requested the Trustee to call a meeting of Debentureholders, by written request setting forth in

reasonable detail the action proposed to be taken at the meeting, and the Trustee shall not have mailed the notice of such meeting within twenty (20) days after receipt of such request, then the Company or such Debentureholders may determine the time and the place for such meeting and may call such meeting to take any action authorized in Section 10.01, by mailing notice thereof as provided in Section 10.02.

Section 10.04 Qualifications for Voting. To be entitled to vote at any meeting of Debentureholders a person shall (a) be a holder of one or more Debentures on the record date pertaining to such meeting or (b) be a person appointed by an instrument in writing as proxy by a holder of one or more Debentures on the record date pertaining to such meeting. The only persons who shall be entitled to be present or to speak at any meeting of Debentureholders shall be the persons entitled to vote at such meeting and their counsel and any representatives of the Trustee and its counsel and any representatives of the Company and its counsel.

Section 10.05 Regulations. Notwithstanding any other provisions of this Indenture, the Trustee may make such reasonable regulations as it may deem advisable for any meeting of Debentureholders, in regard to proof of the holding of Debentures and of the appointment of proxies, and in regard to the appointment and duties of inspectors of votes, the submission and examination of proxies, certificates and other evidence of the right to vote, and such other matters concerning the conduct of the meeting as it shall think fit.

The Trustee shall, by an instrument in writing, appoint a temporary chairman of the meeting, unless the meeting shall have been called by the Company or by Debentureholders as provided in Section 10.03, in which case the Company or the Debentureholders calling the meeting, as the case may be, shall in like manner appoint a temporary chairman. A permanent chairman and a permanent secretary of the meeting shall be elected by vote of the holders of a majority in principal amount of the Debentures represented at the meeting and entitled to vote at the meeting.

Subject to the provisions of Section 9.04, at any meeting each Debentureholders or proxyholder shall be entitled to one vote for each $1,000 principal amount of Debentures held or represented by him; provided, however, that no vote shall be cast or counted at any meeting in respect of any Debenture challenged as not outstanding and ruled by the chairman of the meeting to be not outstanding. The chairman of the meeting shall have no right to vote other than by virtue of Debentures held by him or instruments in writing as aforesaid duly designating him as the proxy to vote on behalf of other Debentureholders. Any meeting of Debentureholders duly called pursuant to the provisions of Section 10.02 or 10.03 may be adjourned from time to time by the holders of a majority of the aggregate principal amount of Debentures represented at the meeting, whether or not constituting a quorum, and the meeting may be held as so adjourned without further notice.

Section 10.06 Voting. The vote upon any resolution submitted to any meeting of Debentureholders shall be by written ballot on which shall be subscribed the signatures of the holders of Debentures or of their representatives by proxy and the outstanding principal amount of the Debentures held or represented by them. The permanent chairman of the meeting shall appoint two inspectors of votes who shall count all votes cast at the meeting for or against any resolution and who shall make and file with the secretary of the meeting their verified written

reports in duplicate of all votes cast at the meeting. A record in duplicate of the proceedings of each meeting of Debentureholders shall be prepared by the secretary of the meeting and there shall be attached to said record the original reports of the inspectors of votes on any vote by ballot taken thereat and affidavits by one or more persons having knowledge of the facts setting forth a copy of the notice of the meeting and showing that said notice was mailed as provided in Section 10.02. The record shall show the principal amount of the Debentures voting in favor of or against any resolution. The record shall be signed and verified by the affidavits of the permanent chairman and secretary of the meeting and one of the duplicates shall be delivered to the Company and the other to the Trustee to be preserved by the Trustee, the latter to have attached thereto the ballots voted at the meeting.

Any record so signed and verified shall be conclusive evidence of the matters therein stated.

Section 10.07 No Delay of Rights by Meeting. Nothing contained in this Article 10 shall be deemed or construed to authorize or permit, by reason of any call of a meeting of Debentureholders or any rights expressly or impliedly conferred hereunder to make such call, any hindrance or delay in the exercise of any right or rights conferred upon or reserved to the Trustee or to the Debentureholders under any of the provisions of this Indenture or of the Debentures.

Section 11.01 Supplemental Indentures Without Consent of Debentureholders. The Company, when authorized by the resolutions of the Board of Directors, and the Trustee may, from time to time, and at any time enter into an indenture or indentures supplemental hereto for one or more of the following purposes:

(a) make provision with respect to the conversion rights of the holders of Debentures pursuant to the requirements of Section 15.06;

(b) subject to Article 4, to convey, transfer, assign, mortgage or pledge to the Trustee as security for the Debentures, any property or assets;

(c) to evidence the succession of another Person to the Company, or successive successions, and the assumption by the successor Person of the covenants, agreements and obligations of the Company pursuant to Article 12;

(d) to add to the covenants of the Company such further covenants, restrictions or conditions as the Board of Directors and the Trustee shall consider to be for the benefit of the holders of Debentures, and to make the occurrence, or the occurrence and continuance, of a default in any such additional covenants, restrictions or conditions a default or an Event of Default permitting the enforcement of all or any of the several remedies provided in this Indenture as herein set forth; provided, however, that in respect of any such additional covenant, restriction or condition, such supplemental indenture may provide for a particular period of grace after default (which period may be shorter or longer than that allowed in the case of other defaults) or may provide for an immediate enforcement upon such default or may limit the remedies available to the Trustee upon such default;

(e) to provide for the issuance under this Indenture of Debentures in coupon form (including Debentures registrable as to principal only) and to provide for exchangeability of such Debentures with the Debentures issued hereunder in fully registered form and to make all appropriate changes for such purpose;

(f) to cure any ambiguity or to correct or supplement any provision contained herein or in any supplemental indenture that may be defective or inconsistent with any other provision contained herein or in any supplemental indenture, provided that such modification or amendment does not, in the good faith opinion of the Company’s Board of Directors and the Trustee materially adversely affect the interests of the holders of the Debentures;

(g) to evidence and provide for the acceptance of appointment hereunder by a successor Trustee with respect to the Debentures;

(h) to increase the Conversion Rate, provided that the increase will not adversely affect the interests of the holders of the Debentures;

(i) to make any changes or modifications necessary in connection with registration of the Debentures under the Securities Act as contemplated in the Registration Rights Agreement; provided that such change or modification does not, in the good faith opinion of the Company’s Board of Directors and the Trustee, materially adversely affect the interests of the holders of the Debentures;

(k) to modify, eliminate or add to the provisions of this Indenture to such extent as shall be necessary to effect or maintain the qualifications of this Indenture under the Trust Indenture Act, or under any similar federal statute hereafter enacted; or

(l) to make such other provisions in regard to matters or questions arising under this Indenture that the Company and the Trustee deem necessary and advisable and that shall not materially adversely affect the interests of the holders of the Debentures.

Upon the written request of the Company, accompanied by a copy of the resolutions of the Board of Directors certified by its Secretary or Assistant Secretary authorizing the execution of any supplemental indenture, the Trustee is hereby authorized to join with the Company in the execution of any such supplemental indenture, to make any further appropriate agreements and stipulations that may be therein contained and to accept the conveyance, transfer and assignment of any property thereunder, but the Trustee shall not be obligated to, but may in its discretion, enter into any supplemental indenture that affects the Trustee’s own rights, duties or immunities under this Indenture or otherwise.

Any supplemental indenture authorized by the provisions of this Section 11.01 may be executed by the Company and the Trustee without the consent of the holders of any of the Debentures at the time outstanding, notwithstanding any of the provisions of Section 11.02.

Notwithstanding any other provision of the Indenture or the Debentures, the Registration Rights Agreement and the obligation to pay Liquidated Damages thereunder may be amended, modified or waived in accordance with the provisions of the Registration Rights Agreement.

Section 11.02 Supplemental Indenture with Consent of Debentureholders. With the consent (evidenced as provided in Article Nine) of the holders of not less than a majority in aggregate principal amount of the Debentures at the time outstanding, the Company, when authorized by the resolutions of the Board of Directors, and the Trustee may, from time to time and at any time, enter into an indenture or indentures supplemental hereto for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of this Indenture or any supplemental indenture or of modifying in any manner the rights of the holders of the Debentures. Notwithstanding the foregoing, without the written consent of each Debentureholder affected, an amendment, supplement or waiver, including a waiver pursuant to Section 7.07 may not:

(ii) reduce the interest rate or change the time of payment of interest or Liquidated Damages on any Debenture;

(iii) reduce the principal amount of any Debenture or premium, if any, thereon, or reduce any amount payable on redemption or repurchase thereof in accordance with Article 3 hereof or reduce the amount of Liquidated Damages payable thereon;

(iv) impair the right of any Debentureholders to institute suit for the enforcement of any payment on a Debenture or with respect to the conversion of a Debenture;

(v) make the principal of any Debenture or interest or premium, if any, or Liquidated Damages on any Debenture payable in any coin or currency other than that provided in the Debentures;

(vi) modify the provisions of this Indenture with respect to the redemption of the Debentures in a manner adverse to the Debentureholders;

(vii) except as contemplated by Article 12 hereof, change the obligation of the Company to repurchase any Debenture upon the happening of a Change of Control in a manner adverse to the holder of Debentures;

(viii) impair or adversely affect the right to convert the Debentures into Common Stock subject to the terms set forth herein in each case, without the consent of the holder of each Debenture so affected;

(ix) alter the manner of calculation or rate of accrual of Liquidated Damages on any Debenture or extend the time for payment of such amount; or

(x) reduce the aforesaid percentage of Debentures, the holders of which are required to consent to any modification, amendment or supplemental indenture or the percentage of Debentures, the holders of which are required for any other waiver under this Indenture.

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

It shall not be necessary for the consent of the Debentureholders under this Section 11.02 to approve the particular form of any proposed supplemental indenture, but it shall be sufficient if such consent shall approve the substance thereof.

Section 11.03 Effect of Supplemental Indenture. Any supplemental indenture executed pursuant to the provisions of this Article 11 shall comply with the Trust Indenture Act, as then in effect, provided that this Section 11.03 shall not require such supplemental indenture or the Trustee to be qualified under the Trust Indenture Act prior to the time such qualification is in fact required under the terms of the Trust Indenture Act or the Indenture has been qualified under the Trust Indenture Act, nor shall it constitute any admission or acknowledgment by any party to such supplemental indenture that any such qualification is required prior to the time such qualification is in fact required under the terms of the Trust Indenture Act or the Indenture has been qualified under the Trust Indenture Act. Upon the execution of any supplemental indenture pursuant to the provisions of this Article 11, this Indenture shall be and be deemed to be modified and amended in accordance therewith and the respective rights, limitation of rights, obligations, duties and immunities under this Indenture of the Trustee, the Company and the holders of Debentures shall thereafter be determined, exercised and enforced hereunder, subject in all respects to such modifications and amendments and all the terms and conditions of any such supplemental indenture shall be and be deemed to be part of the terms and conditions of this Indenture for any and all purposes.

Section 11.04 Notation on Debentures. Debentures authenticated and delivered after the execution of any supplemental indenture pursuant to the provisions of this Article 11 may bear a notation in form approved by the Trustee as to any matter provided for in such supplemental indenture. If the Company or the Trustee shall so determine, new Debentures so modified as to conform, in the opinion of the Trustee and the Board of Directors, to any modification of this Indenture contained in any such supplemental indenture may, at the Company’s expense, be prepared and executed by the Company, authenticated by the Trustee (or an authenticating agent duly appointed by the Trustee pursuant to Section 16.11) and delivered in exchange for the Debentures then outstanding, upon surrender of such Debentures then outstanding.

Section 11.05 Evidence of Compliance of Supplemental Indenture to be Furnished to Trustee. Prior to entering into any supplemental indenture, the Trustee may request an Officers’ Certificate and an Opinion of Counsel as conclusive evidence that any supplemental indenture executed pursuant hereto complies with the requirements of this Article 11.

Section 12.01 Company May Consolidate, Etc, on Certain Terms. Subject to the provisions of Section 12.02, nothing contained in this Indenture or in any of the Debentures shall prevent any consolidation or merger of the Company with or into any other Person or Persons (whether or not affiliated with the Company), or successive consolidations or mergers in which the Company or its successor or successors shall be a party or parties, or shall prevent any sale, conveyance or lease (or successive sales, conveyances or leases) of all or substantially all of the property of the Company, to any other Person (whether or not affiliated with the Company), authorized to acquire and operate the same and that shall be organized under the laws of the United States of America, any state thereof or the District of Columbia; provided, however, that upon any such consolidation, merger, sale, conveyance or lease, the due and punctual payment of the principal of and premium, if any, and interest (including Liquidated Damages, if any) on all of the Debentures, according to their tenor and the due and punctual performance and observance of all of the covenants and conditions of this Indenture to be performed by the Company, shall be expressly assumed, by supplemental indenture satisfactory in form to the Trustee, executed and delivered to the Trustee by the Person (if other than the Company) formed by such consolidation, or into which the Company shall have been merged, or by the Person that shall have acquired or leased such property, and such supplemental indenture shall provide for the applicable conversion rights set forth in Section 15.06; and provided further that, immediately after giving effect to a transaction described above, no Event of Default, and no event which, after notice or lapse of time or both, would become an Event of Default, shall have happened and be continuing.

Section 12.02 Successor Corporation to Be Substituted. In case of any such consolidation, merger, sale, conveyance or lease and upon the assumption by the successor Person, by supplemental indenture, executed and delivered to the Trustee and satisfactory in form to the Trustee, of the due and punctual payment of the principal of and premium, if any, and interest on all of the Debentures and the due and punctual performance of all of the covenants and conditions of this Indenture to be performed by the Company, such successor Person shall succeed to and be substituted for the Company, with the same effect as if it had been named herein as the party of this first part. Such successor Person thereupon may cause to be signed, and may issue either in its own name or in the name of Mentor Graphics Corporation any or all of the Debentures, issuable hereunder that theretofore shall not have been signed by the Company and delivered to the Trustee; and, upon the order of such successor Person instead of the Company and subject to all the terms, conditions and limitations in this Indenture prescribed, the Trustee shall authenticate and shall deliver, or cause to be authenticated and delivered, any Debentures that previously shall have been signed and delivered by the officers of the Company to the Trustee for authentication, and any Debentures that such successor Person thereafter shall cause to be signed and delivered to the Trustee for that purpose. All the Debentures so issued shall in all respects have the same legal rank and benefit under this Indenture as the Debentures theretofore or thereafter issued in accordance with the terms of this Indenture as though all of such Debentures had been issued at the date of the execution hereof. In the event of any such consolidation, merger, sale, conveyance or lease, the Person named as the “Company” in the first paragraph of this Indenture or any successor that shall thereafter have become such in the manner prescribed in this Article 12 may be dissolved, wound up and liquidated at any time thereafter and such Person shall be released from its liabilities as obligor and maker of the Debentures and from its obligations under this Indenture.

In case of any such consolidation, merger, sale, conveyance or lease, such changes in phraseology and foam (but not in substance) may be made in the Debentures thereafter to be issued as may be appropriate.

Section 12.03 Opinion of Counsel to be Given Trustee. The Trustee shall receive an Officers’ Certificate and an Opinion of Counsel as conclusive evidence that any such consolidation, merger, sale, conveyance or lease and any such assumption complies with the provisions of this Article 12.

Section 13.01 Discharge of Indenture. When (a) the Company shall deliver to the Trustee for cancellation all Debentures theretofore authenticated (other than any Debentures that have been destroyed, lost or stolen and in lieu of or in substitution for which other Debentures shall have been authenticated and delivered) and not theretofore canceled, or (b) all the Debentures not theretofore canceled or delivered to the Trustee for cancellation shall have become due and payable, and the Company shall deposit with the Trustee, funds sufficient to pay principal and premium, if any, and interest and Liquidated Damages, if any, due on any outstanding Debentures, accompanied by a verification report, as to the sufficiency of the deposited amount, from an independent certified accountant or other financial professional reasonably satisfactory to the Trustee, and if the Company shall also pay or cause to be paid all other sums payable hereunder by the Company, then this Indenture shall cease to be of further effect (except as to (i) remaining rights of registration of transfer, substitution and exchange and conversion of Debentures, (ii) rights hereunder of Debentureholders to receive payments of principal of and premium, if any, and interest and Liquidated Damages, if any on, the Debentures and the other rights, duties and obligations of Debentureholders, as beneficiaries hereof with respect to the amounts, if any, so deposited with the Trustee and (iii) the rights, obligations and immunities of the Trustee hereunder), and the Trustee, on written demand of the Company accompanied by an Officers’ Certificate and an Opinion of Counsel as required by Section 16.05 and at the cost and expense of the Company, shall execute proper instruments acknowledging satisfaction of and discharging this Indenture; the Company, however, hereby agrees to reimburse the Trustee for any costs or expenses thereafter reasonably and properly incurred by the Trustee and to compensate the Trustee for any services thereafter reasonably and properly rendered by the Trustee in connection with this Indenture or the Debentures.

Section 13.02 Deposited Monies to Be Held in Trust by Trustee. Subject to Section 13.04, all monies deposited with the Trustee pursuant to Section 13.01, provided such deposit was not in violation of Article 4, shall be held in trust for the sole benefit of the Debentureholders and not to be subject to the subordination provisions of Article 4, and such monies shall be applied by the Trustee to the payment, either directly or through any paying agent (including the Company if acting as its own paying agent), to the holders of the particular Debentures for the payment or redemption of which such monies have been deposited with the Trustee, of all sums due and to become due thereon for principal and interest and premium, if any.

Section 13.03 Paying Agent to Repay Monies Held. Upon the satisfaction and discharge of this Indenture, all monies then held by any paying agent of the Debentures (other than the Trustee) shall, upon written request of the Company, be repaid to it or paid to the Trustee, and thereupon such paying agent shall be released from all further liability with respect to such monies.

Section 13.04 Return of Unclaimed Monies. Subject to the requirements of applicable law, any monies deposited with or paid to the Trustee for payment of the principal of, premium, if any, or interest on Debentures and not applied but remaining unclaimed by the holders of Debentures for six months after the date upon which the principal of, premium, if any, or interest on such Debentures, as the case may be, shall have become due and payable, shall be repaid to the Company by the Trustee on demand and all liability of the Trustee shall thereupon cease with respect to such monies; and the holder of any of the Debentures shall thereafter look only to the Company for any payment that such holder may be entitled to collect unless an applicable abandoned property law designates another Person.

Section 13.05 Reinstatement. If the Trustee or the paying agent is unable to apply any money in accordance with Section 13.02 by reason of any order or judgment of any court or governmental authority enjoining, restraining or otherwise prohibiting such application, the Company’s obligations under this Indenture and the Debentures shall be revived and reinstated as though no deposit had occurred pursuant to Section 13.01 until such time as the Trustee or the paying agent is permitted to apply all such money in accordance with Section 13.02; provided, however, that if the Company makes any payment of interest on or principal of any Debenture following the reinstatement of its obligations, the Company shall be subrogated to the rights of the holders of such Debentures to receive such payment from the money held by the Trustee or paying agent.

Section 14.01 Indenture and Debentures Solely Corporate Obligations. No recourse for the payment of the principal of or premium, if any, or interest on any Debenture, or for any claim based thereon or otherwise in respect thereof, and no recourse under or upon any obligation, covenant or agreement of the Company in this Indenture or in any supplemental indenture or in any Debenture, or because of the creation of any indebtedness represented thereby, shall be had against any incorporator, stockholder, employee, agent, officer, director or subsidiary, as such, past, present or future, of the Company or of any successor corporation, either directly or through the Company or any successor corporation, whether by virtue of any constitution, statute or rule of law, or by the enforcement of any assessment or penalty or otherwise; it being expressly understood that all such liability is hereby expressly waived and released as a condition of, and as a consideration for, the execution of this Indenture and the issuance of the Debentures.

(a) Subject to and upon compliance with the provisions of this Indenture and this Article 15, at the option of the Debentureholder thereof, a Debentureholder may convert any Debenture that is an integral multiple of $1,000 into fully paid and nonassessable shares (calculated as to each conversion to the nearest 1/100th of a share) of Common Stock of the Company at the Conversion Rate, determined as hereinafter provided, in effect at the time of conversion and subject to the adjustments described below, as follows:

(i) on any date prior to August 6, 2021, during any fiscal quarter after the fiscal quarter ending September 30, 2003 (and only during such fiscal quarter) if the Closing Price of the Common Stock for at least 20 Trading Days in the period of the 30 consecutive Trading Days ending on the last Trading Day of the immediately preceding fiscal quarter exceeds 120% of the Conversion Price on that 30^th Trading Day;

(ii) on any date on or after August 6, 2021, at any time after the Closing Price of the Common Stock exceeds 120% of the then current Conversion Price;

(iii) if the Debenture have been called for redemption under Section 3.01 hereof at any time prior to the close of business on the Business Day immediately preceding the Redemption Date;

(iv) if the Company distributes to all or substantially all holders of Common Stock rights, options or warrants entitling them to purchase, for a period expiring within 60 days, Common Stock at less than the Current Market Price;

(v) if the Company distributes to all or substantially all holders of Common Stock assets, debt securities or rights to purchase the Companies capital stock, which distribution has a per share value exceeding 10% of the Closing Price of the Common Stock on the Business Day preceding the declaration date for such distribution;

(vi) if the Company distributes to all or substantially all holders of Common Stock cash in the form of a divided;

(vii) if the Company is a party to a consolidation, merger or binding share exchange pursuant to which all or substantially all of its Common Stock would be converted into cash, securities or other property as set forth in Section 15.06;

(ix) if the Company would have undergone a Change of Control but for the existence of one of the following exceptions of to the definition of Change of Control:

(1) the Closing Price of the Common Stock for any five (5) Trading Days during the ten (10) Trading Days immediately preceding the Change of Control is at least equal to at least 105% of the Conversion Price in effect on the date on which the Change of Control occurs; or

(2) all of the consideration (excluding cash payments for fractional shares) in the transaction constituting the Change of Control consists of common stock traded on a United States national securities exchange or quoted on the Nasdaq National Market System (or will be so traded or quoted when issued or exchanged in connection with such Change of Control) and as a result of such transaction or transactions the Debentures become convertible solely into such common stock.

In the case of a distribution contemplated by clauses (iv), (v) or (vi) of this Section 15.01(a), the Company will notify Debentureholders at least 20 days prior to the ex-dividend date for such distribution (the “Distribution Notice”). Once the Company has given the Distribution Notice, Debentureholders may surrender their Debentures for conversion at any time until the earlier of the close of business on the last Business Day preceding the ex-dividend date or the Company’s announcement that such distribution will not take place. Notwithstanding the foregoing, in the event of a distribution contemplated by clauses (iv), (v) or (vi) of this Section 15.01(a), Debentureholders shall not have the right to surrender Debentures for conversion under those sections if they will otherwise participate in the distribution described above without first converting Debentures into Common Stock.

In the case of an event described in clauses (vii), (viii) or (ix) of this Section 15.01(a), Debentureholders may convert their Debentures at any time from and after the date that is 15 days prior to the anticipated effective date of the transaction until 15 days after the actual date of such transaction. If the Company is party to a consolidation, merger or binding share exchange pursuant to which all or substantially all of the Company’s Common Stock is converted into cash, securities or other property, then at the effective time of the transaction, the right to convert a Debenture into shares of Common Stock shall be changed into a right to convert such Debenture into the kind and amount of cash, securities or other property of the Company or another person that the Debentureholder would have received if the Debentureholder had converted such Debenture immediately prior to the transaction.

With respect to clause (i) of this Section 15.01(a), the Conversion Agent will determine, on behalf of the Company, on the first Trading Day succeeding the immediately preceding fiscal quarter whether the Securities are convertible as set forth in such clause (i) as a result of the Closing Price of the Common Stock and the then current Conversion Price and, if so, will notify the Company. With respect to clause (ii) of this section 15.01(a), the Conversion Agent will determine, on behalf of the Company, daily on any date after August 6, 2021, whether the Securities are convertible as set forth in such clause (ii) as a result of the Closing Price of the Common Stock and the then current Conversion Price and, if so, will notify the Company.

(b) Subject to the further provisions of this Article 15, a Debentureholder of a Debenture may also convert the principal amount of such Debenture (or any portion thereof equal to $1,000 or any integral multiple of $1,000 in excess thereof) into Common Stock during the five Trading Day period immediately following any 10 consecutive Trading Day period in which the Market Price per $1,000 principal amount of Debentures for each day of such 10 Trading Day period was less than 98% of the product of the Closing Price and the Conversion

Rate as of each such Trading Day; provided, however, that if, on the date of any conversion pursuant to this Section 15.01(b), the Closing Price of the Common Stock is greater than the Conversion Price then in effect and less than 120% of the Conversion Price then in effect, then Debentureholders surrendering Debentures for conversion shall receive Common Stock with a value equal to the Accreted Principal Amount of the Debentures as of the Conversion Date (a “Principal Value Conversion”). Common Stock delivered pursuant to this Section 15.01(b) will be valued at the Closing Price of the Common Stock on the Conversion Date. The Company will deliver the shares of Common Stock to the Debentureholder no later than the fourth Business Day following the Conversion Date.

In connection with any conversion pursuant to this Section 15.01(b), the Calculation Agent shall not have any obligation to determine the Trading Price of the Debentures unless the Company has requested such determination and the company shall have no obligation to make such request unless a Debentureholder provides the Company with reasonable evidence that the Trading Price per Debenture would be less than 98% of the product of the Closing Price and the Conversion Rate as of such Trading Day. At such time, the Company shall instruct the Calculation Agent to determine the Trading Price of the Debentures beginning on the next Trading Day and on each successive Trading Day until the Trading Price per such Debenture is greater than or equal to 98% of the product of the Closing Price of the Common Stock and the Conversion Rate as of such Trading Day.

The “Market Price” of the Debentures on any date of determination means the average of the secondary market bid quotations per Debenture obtained by the Trustee for $5,000,000 principal amount of the Debentures at approximately 4:00 p.m., New York City time, on such determination date from three unaffiliated nationally recognized securities dealers the Company selects, which may include any of the Initial Purchasers, provided that if at least three such bids cannot be reasonably obtained by the Trustee, but two bids are obtained, then the average of the two bids will be used, and if only one such bid can be reasonably obtained by the Trustee, this one bid will be used. If the Trustee, through the exercise of reasonable efforts, cannot obtain at least one bid for $5,000,000 principal amount of the Debentures from a nationally recognized securities dealer or if in the Company’s reasonable judgment, the bid quotations are not indicative of the secondary market value of the Debentures, then the Market Price of the Debentures will be deemed to be less than 98% of the product of the then current Conversion Rate and the Closing Price of Common Stock on the five Trading Days ending on such determination date, appropriately adjusted.

The Trustee shall have no obligation to determine the Market Price of the Debentures unless the Company has requested such determination in writing; and the Company shall have no obligation to make such request unless a Debentureholder provides the Company with reasonable evidence that the Market Price of the Debentures may be less than 98% of the product of the then current Conversion Rate and the Closing Price of Common Stock on the five Trading Days ending on such determination date. If a Debentureholder provides such evidence, the Company shall instruct the Trustee to determine the Market Price of the Debentures for the applicable period.

(c) The conversion right, subject to the conditions described in clauses (a) and (b) of this Section 15.01, shall commence on the initial issuance date of the Debentures and

expire at the close of business on the date of maturity date of the Debentures, subject, in the case of conversion of any Global Debenture, to any applicable procedures of the Depositary. In case a Debentureholder exercises his right to require the Company to repurchase the Debenture, such conversion right in respect of the Debenture, or portion thereof so called, shall expire at the close of business on the Business Day immediately preceding the Repurchase Date unless the Company defaults in making the payment due upon repurchase (subject as aforesaid to any applicable procedures of the Depositary with respect to any Global Debenture).

Provisions of this Indenture that apply to conversion of all of a Debenture also apply to conversion of a portion of a Debenture.

A Debentureholder is not entitled to any rights of a holder of Common Stock until such Debentureholder has converted its Debentures into Common Stock, and only to the extent such Debentures are deemed to have been converted into Common Stock pursuant to this Article 15.

The rate at which shares of Common Stock shall be delivered upon conversion (herein called the “Conversion Rate”) shall be initially 42.7305 shares of Common Stock for each U.S.$1,000 principal amount of Debentures. The Conversion Rate shall be adjusted in certain instances as provided in this Article 15.

(d) Conversion Right after Election to Have Debentures Redeemed. A Debenture in respect of which a holder is exercising its right to require redemption upon a Purchase Date pursuant to Section 3.05 or a Repurchase Date pursuant to Section 3.06 may be converted only if such holder withdraws its election to exercise such right in accordance with the terms of the Indenture.

Section 15.02 Exercise of Conversion Privilege; Issuance of Common Stock on Conversion; No Adjustment for Interest or Dividends. In order to exercise the conversion privilege with respect to any Debenture in certificated form, the holder of any such Debenture to be converted in whole or in part shall surrender such Debenture, duly endorsed, at an office or agency maintained by the Company pursuant to Section 5.02, accompanied by the funds, if any, required by the penultimate paragraph of this Section 15.02, and shall give written notice of conversion in the form provided on the Debentures (or facsimile thereof) (or such other notice which is acceptable to the Company) to the office or agency that the holder elects to convert such Debenture or the portion thereof specified in said notice. Such notice shall also state the name or names (with address or addresses) in which the certificate or certificates for shares of Common Stock which shall be issuable on such conversion shall be issued, and shall be accompanied by transfer taxes, if required pursuant to Section 15.07. Each such Debenture surrendered for conversion shall, such Debenture, be duly endorsed by, or be accompanied by instruments of transfer in form satisfactory to the Company duly executed by, the holder or his duly authorized attorney.

In order to exercise the conversion privilege with respect to any interest in a Debenture in global form, the beneficial holder must complete, or cause to be completed, the appropriate instruction form for conversion pursuant to the Depository’s book-entry conversion program, deliver, or cause to be delivered, by book-entry delivery an interest in such Debenture in global form, furnish appropriate endorsements and transfer documents if required by the Company or the Trustee or conversion agent, and pay the funds, if any, required by this Section 15.02 and any transfer taxes, if required pursuant to Section 15.07.

As promptly as practicable after satisfaction of the requirements for conversion set forth above, subject to compliance with any restrictions on transfer if shares issuable on conversion are to be issued in a name other than that of the Debentureholders (as if such transfer were a transfer of the Debenture or Debentures (or portion thereof) so converted), the Company shall issue and shall deliver to such Debentureholders at the office or agency maintained by the Company for such purpose pursuant to Section 5.02, a certificate or certificates for the number of full shares of Common Stock issuable upon the conversion of such Debenture or portion thereof as determined by the Company in accordance with the provisions of this Article 15 and a check or cash in respect of any fractional interest in respect of a share of Common Stock arising upon such conversion, calculated by the Company as provided in Section 15.03. In case any Debenture of a denomination greater than $1,000 shall be surrendered for partial conversion, and subject to Section 2.03, the Company shall execute and the Trustee shall authenticate and deliver to the holder of the Debenture so surrendered, without charge to such holder, a new Debenture or Debentures in authorized denominations in an aggregate principal amount equal to the unconverted portion of the surrendered Debenture.

Each conversion shall be deemed to have been effected as to any such Debenture (or portion thereof) on the date on which the requirements set forth above in this Section 15.02 have been satisfied as to such Debenture (or portion thereof) (the “Conversion Date”), and the Person in whose name any certificate or certificates for shares of Common Stock shall be issuable upon such conversion shall be deemed to have become on said date the holder of record of the shares represented thereby; provided, however, that any such surrender on any date when the stock transfer books of the Company shall be closed shall constitute the Person in whose name the certificates are to be issued as the record holder thereof for all purposes on the next succeeding day on which such stock transfer books are open, but such conversion shall be at the Conversion Rate in effect on the date upon which such Debenture shall be surrendered.

Any accrued and unpaid interest to the Conversion Date will be deemed cancelled, extinguished or forfeited upon conversion. The Company will not adjust the Conversion Rate to account for any accrued and unpaid interest or accrued or unpaid liquidated damages.

If a Debenture is surrendered for conversion after the close of business on any record date for an interest payment but prior to the close of business on the Business Day immediately preceding the corresponding Interest Payment Date, Debentureholders will receive on the Interest Payment Date interest accrued on the Debentures, notwithstanding the conversion of the Debentures prior to the Interest Payment Date. At the time such Debentures are surrendered for conversion, Debentureholders shall pay to the Company an amount equal to the interest that has accrued and that will be paid on the Debentures being converted on the Interest Payment Date; provided, however, that no such payment shall be required if there shall exist at the time of

conversion a default in the payment of interest on the Debentures. The preceding sentence shall not apply: (i) to Debentures called by the Company for redemption prior to August 11, 2007, (ii) to Debentures that are converted after being called by the Company for redemption after a record date for an interest payment date but prior to the corresponding interest payment date, or (iii) if a Debentureholder surrenders Debentures for conversion between the record date for the final Interest Payment Date and the opening of business on the final Interest Payment Date.

Upon the conversion of an interest in a Debenture in global form, the Trustee (or other conversion agent appointed by the Company), or the Custodian at the direction of the Trustee (or other conversion agent appointed by the Company), shall make a notation on such Debenture in global form as to the reduction in the principal amount represented thereby. The Company shall notify the Trustee in writing of any conversions of Debentures effected through any conversion agent other than the Trustee.

Section 15.03 Cash Payments in Lieu of Fractional Shares. No fractional shares of Common Stock or scrip representing fractional shares shall be issued upon conversion of Debentures. If more than one Debenture shall be surrendered for conversion at one time by the same holder, the number of full shares that shall be issuable upon conversion shall be computed on the basis of the aggregate principal amount of the Debentures (or specified portions thereof to the extent permitted hereby) so surrendered. If any fractional share of stock would be issuable upon the conversion of any Debenture or Debentures, the Company shall make an adjustment and payment therefor in cash at the current market price thereof to the holder of Debentures. The current market price of a share of Common Stock shall be the Closing Price on the last Business Day immediately preceding the Conversion Date.

Section 15.04 Conversion Rate. The conversion rate shall be as specified in the form of Debenture (herein called the “Conversion Rate”) attached as Exhibit A hereto, subject to adjustment as provided in this Article 15.

Section 15.05 Adjustment of Conversion Rate. The Conversion Rate shall be adjusted from time to time by the Company as follows:

(a) In case the Company shall hereafter pay a dividend or make a distribution to all holders of the outstanding Common Stock in shares of Common Stock, the Conversion Rate shall be increased so that the same shall equal the rate determined by multiplying the Conversion Rate in effect at the opening of business on the date following the date fixed for the determination of stockholders entitled to receive such dividend or other distribution by a fraction, the numerator of which shall be the sum of the number of shares of the Common Stock outstanding at the close of business on the date fixed for determination and the total number of shares constituting such dividend or other distribution, and the denominator of which shall be the number of shares of the Common Stock outstanding at the close of business on the date fixed for such determination such increase to become effective immediately after the opening of business on the day following the date fixed for such determination. For the purpose of this paragraph (a), the number of shares of Common Stock at any time outstanding shall not include shares held in the treasury of the Company. The Company will not pay any dividend or make any distribution on shares of Common Stock held in the treasury of the Company. If any dividend or distribution of the type described in this Section 15.05(a) is declared but not so paid or made, the Conversion Rate shall again be adjusted to the Conversion Rate that would then be in effect if such dividend or distribution had not been declared.

(b) In case the Company shall issue rights or warrants to all holders of its outstanding shares of Common Stock entitling them (for a period expiring within forty-five (45) days after the date fixed for determination of stockholders entitled to receive such rights or warrants) to subscribe for or purchase shares of Common Stock at a price per share less than the Current Market Price (as defined below) on the date fixed for determination of stockholders entitled to receive such rights or warrants, the Conversion Rate shall be adjusted so that the same shall equal the rate determined by multiplying the Conversion Rate in effect immediately prior to the date fixed for determination of stockholders entitled to receive such rights or warrants by a fraction, the numerator of which shall be the number of shares of Common Stock outstanding on the date fixed for determination of stockholders entitled to receive such rights or warrants plus the total number of additional shares of Common Stock offered for subscription or purchase, and the denominator of which shall be the number of shares of Common Stock outstanding at the close of business on the date fixed for determination of stockholders entitled to receive such rights or warrants plus the number of shares that the aggregate offering price of the total number of shares so offered would purchase at such Current Market Price. Such adjustment shall be successively made whenever any such rights or warrants are issued, and shall become effective immediately after the opening of business on the day following the date fixed for determination of stockholders entitled to receive such rights or warrants. To the extent that shares of Common Stock are not delivered after the expiration of such rights or warrants, the Conversion Rate shall be readjusted to the Conversion Rate that would then be in effect had the adjustments made upon the issuance of such rights or warrants been made on the basis of delivery of only the number of shares of Common Stock actually delivered. In the event that such rights or warrants are not so issued, the Conversion Rate shall again be adjusted to be the Conversion Rate that would then be in effect if such date fixed for the determination of stockholders entitled to receive such rights or warrants had not been fixed. In determining whether any rights or warrants entitle the holders to subscribe for or purchase shares of Common Stock at less than such Current Market Price, and in determining the aggregate offering price of such shares of Common Stock, there shall be taken into account any consideration received by the Company for such rights or warrants and any amount payable on exercise or conversion thereof, the value of such consideration, if other than cash, to be determined by the Board of Directors.

(c) In case outstanding shares of Common Stock shall be subdivided into a greater number of shares of Common Stock, the Conversion Rate in effect at the opening of business on the day following the day upon which such subdivision becomes effective shall be proportionately increased, and conversely, in case outstanding shares of Common Stock shall be combined into a smaller number of shares of Common Stock, the Conversion Rate in effect at the opening of business on the day following the day upon which such combination becomes effective shall be proportionately reduced, such increase or reduction, as the case may be, to become effective immediately after the opening of business on the day following the day upon which such subdivision or combination becomes effective.

(d) In case the Company shall, by dividend or otherwise, distribute to all holders of its Common Stock shares of any class of capital stock of the Company (other than any dividends or distributions to which Section 15.05(a) applies) or evidences of its indebtedness or assets

(including securities, but excluding any rights or warrants referred to in Section 15.05(b), and excluding any dividend or distribution (x) referred to in Section 15.05(c) or (y) referred to in Section 15.05(a)) (any of the foregoing hereinafter in this Section 15.05(d) called the “Securities”), then, in each such case (unless the Company elects to reserve such Securities for distribution to the Debentureholders upon the conversion of the Debentures so that any such holder converting Debentures will receive upon such conversion, in addition to the shares of Common Stock to which such holder is entitled, the amount and kind of such Securities which such holder would have received if such holder had converted its Debentures into Common Stock immediately prior to the Record Date (as defined in Section 15.05(h)(4) for such distribution of the Securities)), the Conversion Rate shall be increased so that the same shall be equal to the rate determined by multiplying the Conversion Rate in effect on the Record Date with respect to such distribution by a fraction, the numerator of which shall be the Current Market Price per share of the Common Stock on the Record Date and the denominator of which shall be the Current Market Price per share of the Common Stock on such Record Date less the fair market value (as determined by the Board of Directors, whose determination shall be conclusive, and described in a resolution of the Board of Directors) on the Record Date of the portion of the Securities so distributed applicable to one share of Common Stock, such increase to become effective immediately prior to the opening of business on the day following such Record Date; provided, however, that in the event the then fair market value (as so determined) of the portion of the Securities so distributed applicable to one share of Common Stock is equal to or greater than the Current Market Price of the Common Stock on the Record Date, in lieu of the foregoing adjustment, adequate provision shall be made so that each holder shall have the right to receive upon conversion the amount of Securities such holder would have received had such holder converted each Debenture on the Record Date. In the event that such dividend or distribution is not so paid or made, the Conversion Rate shall again be adjusted to be the Conversion Rate that would then be in effect if such dividend or distribution had not been declared. If the Board of Directors determines the fair market value of any distribution for purposes of this Section 15.05(d) by reference to the actual or when issued trading market for any securities, it must in doing so consider the prices in such market over the same period used in computing the Current Market Price of the Common Stock.

Under the provisions of the Company’s Rights Plan (the “Rights Plan”), upon conversion of the Debentures into Common Stock, to the extent that the Rights Plan is still in effect upon such conversion, the holders of Debentures will receive, in addition to the Common Stock, the rights described therein (whether or not the rights have separated from the Common Stock at the time of conversion), subject to the limitations set forth in the Rights Plan.

Rights or warrants distributed by the Company to all holders of Common Stock entitling the holders thereof to subscribe for or purchase shares of the Company’s capital stock (either initially or under certain circumstances), which rights or warrants, until the occurrence of a specified event or events (“Trigger Event”): (i) are deemed to be transferred with such shares of Common Stock; (ii) are not exercisable; and (iii) are also issued in respect of future issuances of Common Stock, shall be deemed not to have been distributed for purposes of this Section 15.05 (and no adjustment to the Conversion Rate under this Section 15.05 will be required) until the occurrence of the earliest Trigger Event, whereupon such rights and warrants shall be deemed to have been distributed and an appropriate adjustment (if any is required) to the Conversion Rate shall be made under this Section 15.05(d). If any such right or warrant, including any such

existing rights or warrants distributed prior to the date of this Indenture, are subject to events, upon the occurrence of which such rights or warrants become exercisable to purchase different securities, evidences of indebtedness or other assets, then the date of the occurrence of any and each such event shall be deemed to be the date of distribution and record date with respect to new rights or warrants with such rights (and a termination or expiration of the existing rights or warrants without exercise by any of the holders thereof). In addition, in the event of any distribution (or deemed distribution) of rights or warrants, or any Trigger Event or other event (of the type described in the preceding sentence) with respect thereto that was counted for purposes of calculating a distribution amount for which an adjustment to the Conversion Rate under this Section 15.05 was made, (1) in the case of any such rights or warrants that shall all have been redeemed or repurchased without exercise by any holders thereof, the Conversion Rate shall be readjusted upon such final redemption or repurchase to give effect to such distribution or Trigger Event, as the case may be, as though it were a cash distribution, equal to the per share redemption or repurchase price received by a holder or holders of Common Stock with respect to such rights or warrants (assuming such holder had retained such rights or warrants), made to all holders of Common Stock as of the date of such redemption or repurchase, and (2) in the case of such rights or warrants that shall have expired or been terminated without exercise by any holders thereof, the Conversion Rate shall be readjusted as if such rights and warrants had not been issued.

No adjustment of the Conversion Rate shall be made pursuant to this Section 15.05(d) in respect of rights or warrants distributed or deemed distributed on any Trigger Event to the extent that such rights or warrants are actually distributed, or reserved by the Company for distribution to holders of Debentures upon conversion by such holders of Debentures to Common Stock.

For purposes of this Section 15.05(d) and Sections 15.05(a) and (b), any dividend or distribution to which this Section 15.05(d) is applicable that also includes shares of Common Stock, or rights or warrants to subscribe for or purchase shares of Common Stock (or both), shall be deemed instead to be (1) a dividend or distribution of the evidences of indebtedness, assets or shares of capital stock other than such shares of Common Stock or rights or warrants (and any Conversion Rate increase required by this Section 15.05(d) with respect to such dividend or distribution shall then be made) immediately followed by (2) a dividend or distribution of such shares of Common Stock or such rights or warrants (and any further Conversion Rate increase required by Sections 15.05(a) and (b) with respect to such dividend or distribution shall then be made), except (A) the Record Date of such dividend or distribution shall be substituted as “the date fixed for the determination of stockholders entitled to receive such dividend or other distribution”, “the date fixed for the determination of stockholders entitled to receive such rights or warrants” and “the date fixed for such determination” within the meaning of Sections 15.05(a) and (b), and (B) any shares of Common Stock included in such dividend or distribution shall not be deemed “outstanding at the close of business on the date fixed for such determination” within the meaning of Section 15.05(a).

(e) In case the Company shall, on or before August 11, 2007, by dividend or otherwise, distribute to all holders of its Common Stock cash (excluding any cash that is distributed upon a liquidation, distribution or winding up of the Company), or declare such distribution of cash with an “ex-dividend date” on or before August 11, 2007, in any amount, then, and in each such case, immediately after the close of business on such date, the Conversion Rate shall be increased so

that the same shall equal the rate determined by multiplying the Conversion Rate in effect immediately prior to the close of business on such Record Date by a fraction (i) the numerator of which shall be equal to the Current Market Price on the Record Date and (ii) the denominator of which shall be equal to the Current Market Price on such date less an amount equal to the sum of the aggregate amount of cash and the aggregate fair market value (as determined by the Board of Directors, whose determination shall be conclusive evidence thereof and which shall be evidenced by an Officers’ Certificate delivered to the Trustee) of any such other consideration so distributed, paid or payable on the applicable distribution applicable to one share of Common Stock (based on the number of shares of Common Stock outstanding on the Record Date); provided, however, that in the event the portion of the cash so distributed applicable to one share of Common Stock is equal to or greater than the Current Market Price of the Common Stock on the Record Date, in lieu of the foregoing adjustment, adequate provision shall be made so that each Security holder shall have the right to receive upon conversion of a Security (or any portion thereof) the amount of cash such holder would have received had such holder converted such Security (or portion thereof) immediately prior to such Record Date. In the event that such dividend or distribution is not so paid or made, the Conversion Rate shall again be adjusted to be the Conversion Rate which would then be in effect if such dividend or distribution had not been declared. Any cash distribution to all holders of Common Stock as to which the Company makes the election permitted by Section 15.05(n) and as to which the Company has complied with the requirements of such Section shall be treated as not having been made for all purposes of this Section 15.05(e). For purposes of this paragraph, the term “ex-dividend date” means the first date on which the Common Stock trades regular way in the applicable securities market or on the applicable securities exchange without the right to receive such distribution.

(f) In case a tender offer made by the Company or any of its subsidiaries for all or any portion of the Common Stock shall expire and such tender offer (as amended upon the expiration thereof) shall require the payment to stockholders (based on the acceptance (up to any maximum specified in the terms of the tender offer) of Purchased Shares (as defined below)) of an aggregate consideration having a fair market value (as determined by the Board of Directors, whose good faith determination shall be conclusive and described in a resolution of the Board of Directors) that combined together with the aggregate of the cash plus the fair market value (as determined by the Board of Directors, whose good faith determination shall be conclusive and described in a resolution of the Board of Directors), as of the expiration of such tender offer, of consideration payable in respect of any other tender offers, by the Company or any of its subsidiaries for all or any portion of the Common Stock expiring within the 12 months preceding the expiration of such tender offer and in respect of which no adjustment pursuant to this Section 15.05(f) has been made, exceeds ten percent (10%) of the product of the Current Market Price as of the last time (the “Expiration Time”) tenders could have been made pursuant to such tender offer (as it may be amended) and the number of shares of Common Stock outstanding (including any tendered shares) at the Expiration Time, then, and in each such case, immediately prior to the opening of business on the day after the date of the Expiration Time, the Conversion Rate shall be increased so that the same shall equal the rate determined by multiplying the Conversion Rate in effect immediately prior to close of business on the date of the Expiration Time by a fraction of which the numerator of which shall be the sum of (x) the fair market value (determined as aforesaid) of the aggregate consideration payable to stockholders based on the acceptance (up to any maximum specified in the terms of the tender offer) of all shares validly tendered and not withdrawn as of the Expiration Time (the shares deemed so accepted, up to any

such maximum, being referred to as the “Purchased Shares”) and (y) the product of the number of shares of Common Stock outstanding (less any Purchased Shares) at the Expiration Time and the Current Market Price of the Common Stock on the Trading Day next succeeding the Expiration Time, and the denominator of which shall be the number of shares of Common Stock outstanding (including any tendered shares) at the Expiration Time multiplied by the Current Market Price of the Common Stock on the Trading Day next succeeding the Expiration Time, such increase (if any) to become effective immediately prior to the opening of business on the day following the Expiration Time. In the event that the Company is obligated to purchase shares pursuant to any such tender offer, but the Company is permanently prevented by applicable law from effecting any such purchases or all such purchases are rescinded, the Conversion Rate shall again be adjusted to be the Conversion Rate which would then be in effect if such tender offer had not been made. If the application of this Section 15.05(f) to any tender offer would result in an increase in the Conversion Rate, no adjustment shall be made for such tender offer under this Section 15.05(f). Any cash distribution to all holders of Common Stock as to which the Company makes the election permitted by Section 15.05(n) and as to which the Company has complied with the requirements of such Section shall be treated as not having been made for all purposes of this Section 15.05(f).

(g) In case of a tender or exchange offer made by a Person other than the Company or any Subsidiary for an amount that increases the offeror’s ownership of Common Stock to more than twenty-five percent (25%) of the Common Stock outstanding and shall involve the payment by such Person of consideration per share of Common Stock having a fair market value (as determined by the Board of Directors, whose determination shall be conclusive, and described in a resolution of the Board of Directors) that as of the last time (the “Offer Expiration Time”) ,tenders or exchanges may be made pursuant to such tender or exchange offer (as it shall have been amended) that exceeds the Current Market Price of the Common Stock on the Trading Day next succeeding the Offer Expiration Time, and in which, as of the Offer Expiration Time the Board of Directors is not recommending rejection of the offer, the Conversion Rate shall be increased so that the same shall equal the rate determined by multiplying the Conversion Rate in effect immediately prior to the Offer Expiration Time by a fraction the numerator of which shall be the sum of (x) the fair market value (determined as aforesaid) of the aggregate consideration payable to stockholders based on the acceptance (up to any maximum specified in the terms of the tender or exchange offer) of all shares validly tendered or exchanged and not withdrawn as of the Offer Expiration Time (the shares deemed so accepted, up to any such maximum, being referred to as the “Accepted Purchased Shares”) and (y) the product of the number of shares of Common Stock outstanding (less any Accepted Purchased Shares) at the Offer Expiration Time and the Current Market Price of the Common Stock on the Trading Day next succeeding the Offer Expiration Time, and the denominator of which shall be the number of shares of Common Stock outstanding (including any tendered or exchanged shares) at the Offer Expiration Time multiplied by the Current Market Price of the Common Stock on the Trading Day next succeeding the Offer Expiration Time, such increase to become effective immediately prior to the opening of business on the Trading Day following the Offer Expiration Time. In the event that such Person is obligated to purchase shares pursuant to any such tender or exchange offer, but such Person is permanently prevented by applicable law from effecting any such purchases or all such purchases are rescinded, the Conversion Rate shall again be adjusted to be the Conversion Rate that would then be in effect if such tender or exchange offer had not been made. Notwithstanding the foregoing, the adjustment described in this Section 15.05(g) shall not be made if, as of the Offer Expiration Time, the offering documents with respect to such offer disclose a plan or intention to cause the Company to engage in any transaction described in Article 12.

(h) For purposes of this Section 15.05, the following terms shall have the meaning indicated:

(1) “Closing Price” with respect to any security on any day shall mean the closing per share sale price (or if no closing sale price per share is reported, the average of the bid and ask prices or, if there is more than one bid or ask price, the average of the average bid and average ask prices) as reported in composite transactions for the principal U.S. national securities exchange on which the security is traded or, if the security is not listed on a U.S. national securities exchange, as reported by the National Association of Securities Dealers. In the absence of such a quotation, the Closing Price shall be a price determined in good faith by the Board of Directors or, to the extent permitted by applicable law, a duly authorized committee thereof, whose determination shall be conclusive.

(2) “Current Market Price” shall mean the average of the daily Closing Prices per share of Common Stock for the ten (10) consecutive Trading Days immediately prior to the Record Date (or if earlier, the ex-dividend date) with respect to any dividend, issuance or other event requiring such computation.

(3) “fair market value” shall mean the amount which a willing buyer would pay a willing seller in an arm’s-length transaction.

(4) “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 or by statute, contract or otherwise).

(5) “Trading Day” shall mean (x) if the applicable security is quoted on the Nasdaq National Market, a day on which trades may be made thereon or (y) if the applicable security is listed or admitted for trading on the New York Stock Exchange or another national securities exchange, a day on which the New York Stock Exchange or another national securities exchange is open for business or (z) if the applicable security is not so listed, admitted for trading or quoted, any day other than a Saturday or Sunday or a day on which banking institutions in the State of New York are authorized or obligated by law or executive order to close.

(i) The Company may make such increases in the Conversion Rate, in addition to those required by Sections 15.05(a), (b), (c), (d), (e), (f) or (g) as the Board of Directors considers to be advisable to avoid or diminish any income tax to holders of Common Stock or rights to purchase Common Stock resulting from any dividend or distribution of stock (or rights to acquire stock) or from any event treated as such for income tax purposes.

To the extent permitted by applicable law, the Company from time to time may increase the Conversion Rate by any amount for any period of time if the period is at least twenty (20)

days, the increase is irrevocable during the period and the Board of Directors shall have made a determination that such increase would be in the best interests of the Company, which determination shall be conclusive. Whenever the Conversion Rate is increased pursuant to the preceding sentence, the Company shall mail to holders of record of the Debentures a notice of the reduction at least fifteen (15) days prior to the date the increased Conversion Rate takes effect, and such notice shall state the increased Conversion Rate and the period during which it will be in effect.

(j) No adjustment in the Conversion Rate shall be required unless such adjustment would require an increase or decrease of at least one percent (1%) in such price; provided, however, that any adjustments that by reason of this Section 15.05(j) are not required to be made shall be carried forward and taken into account in any subsequent adjustment. All calculations under this Article 15 shall be made by the Company and shall be made to the nearest one-ten-thousandth (1/10,000) of a share, as the case may be. No adjustment need be made for rights to purchase Common Stock pursuant to a Company plan for reinvestment of dividends or interest. To the extent the Debentures become convertible into cash, assets, property or securities (other than capital stock of the Company), no adjustment need be made thereafter as to the cash, assets, property or such securities. Interest will not accrue on the cash.

(k) Whenever the Conversion Rate is adjusted as herein provided, the Company shall promptly file with the Trustee and any conversion agent other than the Trustee an Officers’ Certificate setting forth the Conversion Rate (and the derivative Conversion Price) after such adjustment and setting forth a brief statement of the facts requiring such adjustment. Unless and until a Responsible Officer of the Trustee shall have received such Officers’ Certificate, the Trustee shall not be deemed to have knowledge of any adjustment of the Conversion Rate and may assume that the last Conversion Rate of which it has knowledge is still in effect. Promptly after delivery of such certificate, the Company shall prepare a notice of such adjustment of the Conversion Rate setting forth the adjusted Conversion Rate and the date on which each adjustment becomes effective and shall mail such notice of such adjustment of the Conversion Rate to the holder of each Debenture at his last address appearing on the Debenture register provided for in Section 2.05 of this Indenture, within twenty (20) days after execution thereof. Failure to deliver such notice shall not affect the legality or validity of any such adjustment.

(l) In any case in which this Section 15.05 provides that an adjustment shall become effective immediately after (1) a record date or Record Date for an event, (2) the date fixed for the determination of stockholders entitled to receive a dividend or distribution pursuant to Section 15.05(a), (3) a date fixed for the determination of stockholders entitled to receive rights or warrants pursuant to Section 15.05(b), (4) the Expiration Time for any tender or exchange offer pursuant to Section 15.05(f), or (5) the Offer Expiration Time for a tender or exchange offer pursuant to Section 15.05(g) (each a “Determination Date”), the Company may elect to defer until the occurrence of the relevant Adjustment Event (as hereinafter defined) (x) issuing to the holder of any Debenture converted after such Determination Date and before the occurrence of such Adjustment Event, the additional shares of Common Stock or other securities issuable upon such conversion by reason of the adjustment required by such Adjustment Event over and above the Common Stock issuable upon such conversion before giving effect to such adjustment and (y) paying to such holder any amount in cash in lieu of any fraction pursuant to Section 15.03. For purposes of this Section 15.05(1), the term “Adjustment Event” shall mean:

(ii) in any case referred to in clause (2) hereof, the date any such dividend or distribution is paid or made,

(iii)in any case referred to in clause (3) hereof, the date of expiration of such rights or warrants, and

(iv) in any case referred to in clause (4) or clause (5) hereof, the date a sale or exchange of Common Stock pursuant to such tender or exchange offer is consummated and becomes irrevocable.

(m) For purposes of this Section 15.05, the number of shares of Common Stock at any time outstanding shall not include shares held in the treasury of the Company but shall include shares issuable in respect of scrip certificates issued in lieu of fractions of shares of Common Stock. The Company will not pay any dividend or make any distribution on shares of Common Stock held in the treasury of the Company.

(n) In lieu of making any adjustment to the Conversion Rate pursuant to Section 15.05(e) or 15.05(f), the Company may elect to reserve an amount of cash for distribution to the holders of the Debentures upon the conversion of the Debentures so that any such holder converting Debentures will receive upon such conversion, in addition to the shares of Common Stock and other items to which such holder is entitled, the full amount of cash which such holder would have received if such holder had, immediately prior to the Record Date for such distribution of cash or the Expiration Time of the tender offer, as the case may be, converted its Debentures into Common Stock, together with any interest accrued with respect to such amount, in accordance with this Section 15.05(n). The Company may make such election by providing an Officers’ Certificate to the Trustee to such effect on or prior to the payment date for any such distribution and depositing with the Trustee on or prior to such date an amount of cash equal to the aggregate amount the holders of the Debentures would have received if such holders had, immediately prior to the Record Date for such distribution or the Expiration Time, as the case may be, converted all of the Debentures into Common Stock. Any such funds so deposited by the Company with the Trustee shall be invested by the Trustee pursuant to written direction by the Company in marketable obligations issued or fully guaranteed by the United States government with a maturity not more than 3 months from the date of issuance. Upon conversion of Debentures by a holder, the holder will be entitled to receive, in addition to the Common Stock issuable upon conversion, an amount of cash equal to the amount such holder would have received if such holder had, immediately prior to the Record Date for such distribution or the Expiration Time, as the case may be, converted its Debenture into Common Stock, along with such holder’s pro rata share of any accrued interest earned as a consequence of the investment of such funds. Promptly after making an election pursuant to this Section 15.05(n), the Company shall give or shall cause to be given notice to all Debentureholders of such election, which notice shall state the amount of cash per $1,000 principal amount of Debentures such holders shall be entitled to receive (excluding interest) upon conversion of the Debentures as a consequence of the Company having made such election.

Section 15.06 Effect of Reclassification, Consolidation, Merger or Sale. If any of the following events occur, namely (i) any reclassification or change of the outstanding shares of Common Stock (other than a subdivision or combination to which Section 15.05(c) applies), (ii) any consolidation, merger or combination of the Company with another Person as a result of which holders of Common Stock shall be entitled to receive stock, other securities or other property or assets (including cash) with respect to or in exchange for such Common Stock, or (iii) any sale or conveyance of all or substantially all of the properties and assets of the Company to any other Person as a result of which holders of Common Stock shall be entitled to receive stock, other securities or other property or assets (including cash) with respect to or in exchange for such Common Stock, then the Company or the successor or purchasing Person, as the case may be, shall execute with the Trustee a supplemental indenture (which shall comply with the Trust Indenture Act as in force at the date of execution of such supplemental indenture) providing that each Debenture shall be convertible into the kind and amount of shares of stock, other securities or other property or assets (including cash) receivable upon such reclassification, change, consolidation, merger, combination, sale or conveyance by a holder of a number of shares of Common Stock issuable upon conversion of such Debenture (assuming, for such purposes, a sufficient number of authorized shares of Common Stock are available to convert all such Debentures) immediately prior to such reclassification, change, consolidation, merger, combination, sale or conveyance assuming such holder of Common Stock did not exercise such holder’s rights of election, if any, as to the kind or amount of stock, other securities or other property or assets (including cash) receivable upon such reclassification, change, consolidation,. merger, combination, sale or conveyance (provided that, if the kind or amount of stock, other securities or other property or assets (including cash) receivable upon such reclassification, change, consolidation, merger, combination, sale or conveyance is not the same for each share of Common Stock in respect of which such rights of election shall not have been exercised (“non-electing share”), then for the purposes of this Section 15.06 the kind and amount of stock, other securities or other property or assets (including cash) receivable upon such reclassification, change, consolidation, merger, combination, sale or conveyance for each non-electing share shall be deemed to be the kind and amount so receivable per share by a plurality of the non-electing shares). Such supplemental indenture shall provide for adjustments which shall be as nearly equivalent as may be practicable to the adjustments provided for in this Article 15.

The Company shall cause notice of the execution of such supplemental indenture to be mailed to each holder of Debentures, at its address appearing on the Debenture register provided for in Section 2.05 of this Indenture, within twenty (20) days after execution thereof. Failure to deliver such notice shall not affect the legality or validity of such supplemental indenture.

The above provisions of this Section shall similarly apply to successive reclassifications, changes, consolidations, mergers, combinations, sales and conveyances.

If this Section 15.06 applies to any event or occurrence, Section 15.05 shall not apply.

Section 15.07 Taxes on Shares Issued. The issue of stock certificates on conversions of Debentures shall be made without charge to the converting Debentureholders for any tax in respect of the issue thereof. The Company shall not, however, be required to pay any tax which may be payable in respect of any transfer involved in the issue and delivery of stock in any name other than that of the holder of any Debenture converted, and the Company shall not be required to issue or deliver any such stock certificate unless and until the Person or Persons requesting the issue thereof shall have paid to the Company the amount of such tax or shall have established to the satisfaction of the Company that such tax has been paid.

Section 15.08 Reservation of Shares; Shares to Be Fully Paid; Compliance with Governmental Requirements; Listing of Common Stock. The Company shall provide, free from preemptive rights, out of its authorized but unissued shares or shares held in treasury, sufficient shares of Common Stock to provide for the conversion of the Debentures from time to time as such Debentures are presented for conversion.

Before taking any action which would cause an adjustment reducing the Conversion Price below the then par value, if any, of the shares of Common Stock issuable upon conversion of the Debentures, the Company will take all corporate action which may, in the opinion of its counsel, be necessary in order that the Company may validly and legally issue shares of such Common Stock at such adjusted Conversion Price

The Company covenants that all shares of Common Stock which may be issued upon conversion of Debentures will upon issue be fully paid and non-assessable by the Company and free from all taxes, liens and charges with respect to the issue thereof.

The Company covenants that, if any shares of Common Stock to be provided for the purpose of conversion of Debentures hereunder require registration with or approval of any governmental authority under any federal or state law before such shares may be validly issued upon conversion, the Company will in good faith and as expeditiously as possible, to the extent then permitted by the rules and interpretations of the Commission (or any successor thereto), endeavor to secure such registration or approval, as the case may be.

The Company further covenants that, if at any time the Common Stock shall be listed on the Nasdaq National Market or any other national securities exchange or automated quotation system, the Company will, if permitted by the rules of such exchange or automated quotation system, list and keep listed, so long as the Common Stock shall be so listed on such exchange or automated quotation system, all Common Stock issuable upon conversion of the Debentures; provided, however, that, if the rules of such exchange or automated quotation system permit the Company to defer the listing of such Common Stock until the first conversion of the Debentures into Common Stock in accordance with the provisions of this Indenture, the Company covenants to list such Common Stock issuable upon conversion of the Debentures in accordance with the requirements of such exchange or automated quotation system at such time.

Section 15.09 Responsibility of Trustee. The Trustee and any other conversion agent shall not at any time be under any duty or responsibility to any holder of Debentures to determine the Conversion Rate or whether any facts exist which may require any adjustment of the Conversion Rate, or with respect to the nature or extent or calculation of any such adjustment when made, or with respect to the method employed, or herein or in any supplemental indenture provided to be employed, in making the same. The Trustee and any other conversion agent shall not be accountable with respect to the validity or value (or the kind or amount) of any shares of Common Stock, or of any securities or property, which may at any time be issued or delivered upon the conversion of any Debenture; and the Trustee and any other conversion agent make no

representations with respect thereto. Neither the Trustee nor any conversion agent shall be responsible for any failure of the Company to issue, transfer or deliver any shares of Common Stock or stock certificates or other securities or property or cash upon the surrender of any Debenture for the purpose of conversion or to comply with any of the duties, responsibilities or covenants of the Company contained in this Article 15. Without limiting the generality of the foregoing, neither the Trustee nor any conversion agent shall be under any responsibility to determine the correctness of any provisions contained in any supplemental indenture entered into pursuant to Section 15.06 relating either to the kind or amount of shares of stock or securities or property (including cash) receivable by Debentureholders upon the conversion of their Debentures after any event referred to in such Section 15.06 or to any adjustment to be made with respect thereto, but, subject to the provisions of Section 8.01, may accept as conclusive evidence of the correctness of any such provisions, and shall be protected in relying upon, the Officers’ Certificate (which the Company shall be obligated to file with the Trustee prior to the execution of any such supplemental indenture) with respect thereto.

(a) the Company shall declare a dividend (or any other distribution) on its Common Stock that would require an adjustment in the Conversion Rate pursuant to Section 15.05; or

(b) the Company shall authorize the granting to the holders of all or substantially all of its Common Stock of rights or warrants to subscribe for or purchase any share of any class or any other rights or warrants; or

(c) of any reclassification or reorganization of the Common Stock of the Company (other than a subdivision or combination of its outstanding Common Stock, or a change in par value, or from par value to no par value, or from no par value to par value), or of any consolidation or merger to which the Company is a party and for which approval of any stockholders of the Company is required, or of the sale or transfer of all or substantially all of the assets of the Company or any Designated Subsidiary; or

(d) of the voluntary or involuntary dissolution, liquidation or winding up of the Company or any Designated Subsidiary;

the Company shall cause to be filed with the Trustee and to be mailed to each holder of Debentures at his address appearing on the Debenture register provided for in Section 2.05 of this Indenture, as promptly as possible but in any event at least ten (10) days prior to the applicable date hereinafter specified, a notice stating (x) the date on which a record is to be taken for the purpose of such dividend, distribution or rights or warrants, or, if a record is not to be taken, the date as of which the holders of Common Stock of record to be entitled to such dividend, distribution or rights are to be determined, or (y) the date on which such reclassification, consolidation, merger, sale, transfer, dissolution, liquidation or winding up is expected to become effective or occur, and the date as of which it is expected that holders of Common Stock of record shall be entitled to exchange their Common Stock for securities or other property deliverable upon such reclassification, consolidation, merger, sale, transfer, dissolution, liquidation or winding up. Failure to give such notice, or any defect therein, shall not affect the legality or validity of such dividend, distribution, reclassification, consolidation, merger, sale, transfer, dissolution, liquidation or winding up.

Section 16.01 Provisions Binding on Company’s Successors. All the covenants, stipulations, promises and agreements by the Company contained in this Indenture shall bind its successors and assigns whether so expressed or not.

Section 16.02 Official Acts by Successor Corporation. Any act or proceeding by any provision of this Indenture authorized or required to be done or performed by any board, committee or officer of the Company shall and may be done and performed with like force and effect by the like board, committee or officer of any Person that shall at the time be the lawful sole successor of the Company.

Section 16.03 Addresses for Notices, Etc. Any notice or demand which by any provision of this Indenture is required or permitted to be given or served by the Trustee or by the holders of Debentures on the Company shall be deemed to have been sufficiently given or made, for all. purposes, if given or served by being deposited postage prepaid by registered or certified mail in a post office letter box addressed (until another address is filed by the Company with the Trustee) to Mentor Graphics Corporation, 8005 SW Boeckman Road, Wilsonville, Oregon 97070-7777 Attention: General Counsel. Any notice, direction, request or demand hereunder to or upon the Trustee shall be deemed to have been sufficiently given or made, for all purposes, if given or served by being deposited, postage prepaid, by registered or certified mail in a post office letter box addressed to the Corporate Trust Office, which office is, at the date as of which this Indenture is dated, located at c/o Computershare Trust Company of New York, Wall Street Plaza, 88 Pine Street, 19th floor, New York, NY 10005 Attn: Wilmington Trust (Mentor Graphics Corporation, Floating Rate Convertible Subordinated Debentures due 2023).

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

Any notice or communication mailed to a Debentureholders shall be mailed to such Debentureholders by first class mail, postage prepaid, at his address as it appears on the Debenture register and shall be sufficiently given to such Debentureholders if so mailed within the time prescribed.

Failure to mail a notice or communication to a Debentureholders or any defect in it shall not affect its sufficiency with respect to other Debentureholders. If a notice or communication is mailed in the manner provided above, it is duly given, whether or not the addressee receives it.

Section 16.04 Governing Law. This Indenture and each Debenture shall be deemed to be a contract made under the laws of the State of New York, and for all purposes shall be construed in accordance with the laws of the State of New York, without regard to the conflict of laws provisions thereof.

Section 16.05 Evidence of Compliance with Conditions Precedent; Certificates to Trustee. Upon any application or demand by the Company to the Trustee to take any action under any of the provisions of this Indenture, the Company shall furnish to the Trustee an Officers’ Certificate stating that all conditions precedent, if any, provided for in this Indenture relating to the proposed action have been complied with, and, if requested by Trustee, an Opinion of Counsel stating that, in the opinion of such counsel, all such conditions precedent have been complied with.

Each certificate or opinion provided for in this Indenture and delivered to the Trustee with respect to compliance with a condition or covenant provided for in this Indenture shall include: (1) a statement that the person making such certificate or opinion has read such covenant or condition; (2) a brief statement as to the nature and scope of the examination or investigation upon which the statement or opinion contained in such certificate or opinion is based; (3) a statement that, in the opinion of such person, he or she has made such examination or investigation as is necessary to enable him or her to express an informed opinion as to whether or not such covenant or condition has been complied with; and (4) a statement as to whether or not, in the opinion of such person, such condition or covenant has been complied with.

Section 16.06 Legal Holidays. In any case in which the date of maturity of interest on or principal of the Debentures or the date fixed for redemption of any Debenture will not be a Business Day, then payment of such interest on or principal of the Debentures need not be made on such date, but may be made on the next succeeding Business Day with the same force and effect as if made on the date of maturity or the date fixed for redemption, and no interest shall accrue for the period from and after such date.

Section 16.07 Trust Indenture Act. This Indenture is hereby made subject to, and shall be governed by, the provisions of the Trust Indenture Act required to be part of and to govern indentures qualified under the Trust Indenture Act; provided, however, that, unless otherwise required by law, notwithstanding the foregoing, this Indenture and the Debentures issued hereunder shall not be subject to the provisions of subsections (a)(1), (a)(2), and (a)(3) of Section 314 of the Trust Indenture Act as now in effect or as hereafter amended or modified; provided further that this Section 16.07 shall not require this Indenture or the Trustee to be qualified under the Trust Indenture Act prior to the time such qualification is in fact required under the terms of the Trust Indenture Act, nor shall it constitute any admission or acknowledgment by any party to the Indenture that any such qualification is required prior to the time such qualification is in fact required under the terms of the Trust Indenture Act. If any provision hereof limits, qualifies or conflicts with another provision hereof which is required to be included in an indenture qualified under the Trust Indenture Act, such required provision shall control.

Section 16.08 No Security Interest Created. Nothing in this Indenture or in the Debentures, expressed or implied, shall be construed to constitute a security interest under the Uniform Commercial Code or similar legislation, as now or hereafter enacted and in effect, in any jurisdiction in which property of the Company or its subsidiaries is located.

Section 16.09 Benefits of Indenture. Nothing in this Indenture or in the Debentures, express or implied, shall give to any Person, other than the parties hereto, any paying agent, any authenticating agent, any Debenture registrar and their successors hereunder, the holders of Debentures and the holders of Senior Debt, any benefit or any legal or equitable right, remedy or claim under this Indenture.

Section 16.10 Table of Contents, Headings, Etc. The table of contents and the titles and headings of the articles and Sections of this Indenture have been inserted for convenience of reference only, are not to be considered a part hereof, and shall in no way modify or restrict any of the terms or provisions hereof.

Section 16.11 Authenticating Agent. The Trustee may appoint an authenticating agent that shall be authorized to act on its behalf, and subject to its direction, in the authentication and delivery of Debentures in connection with the original issuance thereof and transfers and exchanges of Debentures hereunder, including under Sections 2.04, 2.05, 2.06, 2.07, 3.03, 3.05 and 3.06, as fully to all intents and purposes as though the authenticating agent had been expressly authorized by this Indenture and those Sections to authenticate and deliver Debentures. For all purposes of this Indenture, the authentication and delivery of Debentures by the authenticating agent shall be deemed to be authentication and delivery of such Debentures “by the Trustee” and a certificate of authentication executed on behalf of the Trustee by an authenticating agent shall be deemed to satisfy any requirement hereunder or in the Debentures for the Trustee’s certificate of authentication. Such authenticating agent shall at all times be a Person eligible to serve as trustee hereunder pursuant to Section 8.09.

Any corporation into which any authenticating agent may be merged or converted or with which it may be consolidated, or any corporation resulting from any merger, consolidation or conversion to which any authenticating agent shall be a party, or any corporation succeeding to the corporate trust business of any authenticating agent, shall be the successor of the authenticating agent hereunder, if such successor corporation is otherwise eligible under this Section 16.11, without the execution or filing of any paper or any further act on the part of the parties hereto or the authenticating agent or such successor corporation.

Any authenticating agent may at any time resign by giving written notice of resignation to the Trustee and to the Company. The Trustee may at any time terminate the agency of any authenticating agent by giving written notice of termination to such authenticating agent and to the Company. Upon receiving such a notice of resignation or upon such a termination, or in case at any time any authenticating agent shall cease to be eligible under this Section, the Trustee shall either promptly appoint a successor authenticating agent or itself assume the duties and obligations of the former authenticating agent under this Indenture and, upon such appointment of a successor authenticating agent, if made, shall give written notice of such appointment of a successor authenticating agent to the Company and shall mail notice of such appointment of a successor authenticating agent to all holders of Debentures as the names and addresses of such holders appear on the Debenture register.

The Company agrees to pay to the authenticating agent from time to time such reasonable compensation for its services as shall be agreed upon in writing between the Company and the authenticating agent.

The provisions of Sections 8.02, 8.03, 8.04, 9.03 and this Section 16.11 shall be applicable to any authenticating agent.

Section 16.12 Execution in Counterparts. This Indenture may be executed in any number of counterparts, each of which shall be an original, but such counterparts shall together constitute but one and the same instrument.

Section 16.13 Severability. In case any provision in this Indenture or in the Debentures shall be invalid, illegal or unenforceable, then (to the extent permitted by law) the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.

Wilmington Trust Company hereby accepts the trusts in this Indenture declared and provided, upon the terms and conditions herein above set forth.

IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be duly executed.

MENTOR GRAPHICS CORPORATION
As Issuer

By:		/s/ Dean M. Freed
Name: Dean M. Freed
Title: Vice President and General Counsel

WILMINGTON TRUST COMPANY, as Trustee

By:		/s/ Christopher J. Slaybaugh
Name: Christopher J. Slaybaugh
Title: Financial Services Officer

For Global Debenture only: UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK) (THE “DEPOSITARY”, WHICH TERM INCLUDES ANY SUCCESSOR DEPOSITARY FOR THE CERTIFICATES) 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 REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITARY (AND ANY PAYMENT HEREIN IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITARY), ANY TRANSFER, PLEDGE, OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

THE HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE HEREOF, AGREES TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE “RESALE RESTRICTION TERMINATION DATE”) WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH MENTOR GRAPHICS CORPORATION OR ANY AFFILIATE OF MENTOR GRAPHICS CORPORATION WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY) ONLY (A) TO MENTOR GRAPHICS CORPORATION 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 WHICH 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 MENTOR GRAPHICS CORPORATION’S AND THE TRUSTEE’S RIGHT 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, A CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON THE OTHER SIDE OF THIS SECURITY IS COMPLETED AND DELIVERED BY THE TRANSFEROR TO THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.

Mentor Graphics Corporation, a corporation duly organized and validly existing under the laws of the State of Oregon (herein called the “Company,” which term includes any successor corporation under the Indenture referred to on the reverse hereof), for value received hereby promises to pay to , or registered assigns, the principal sum of dollars ($ ) on August 6, 2023, at the office or agency of the Company maintained for that purpose in accordance with the terms of the Indenture, in such coin or currency of the United States of America as at the time of payment shall be legal tender for the payment of public and private debts, and to pay interest, quarterly in arrears on February 6, May 6, August 6 and November 6 of each year (each an “Interest Payment Date”), commencing November 6, 2003, on said principal sum at said office or agency, in like coin or currency, at the rate equal to 3-month LIBOR plus 1.65% per annum as initially set on August 6, 2003 and then reset quarterly on each February 6, May 6, August 6 and November 6 (each a “Reset Date”), commencing November 6, 2003, from the most recent date to which interest has been paid or duly provided for, or if no interest has been paid or duly provided for, from August 6, 2003, until payment of said principal sum has been made or duly provided for. If interest is not paid when due on any Interest Payment Date, such unpaid interest will start accruing at the new interest rate in effect following such Interest Payment Date. Except as otherwise provided in the Indenture, the interest payable on the Debenture pursuant to the Indenture on any February 6, May 6, August 6 or November 6 will be paid to the Person entitled thereto as it appears in the Debenture register at the close of business on the record date, which shall be the January 21, April 21, July 21 or October 21 (whether or not a Business Day) immediately preceding such February 6, May 6, August 6 or November 6, as provided in the Indenture; provided, however, that any such interest not punctually paid or duly provided for shall be payable as provided in the Indenture. Interest may, at the option of the Company, be paid either (i) by check mailed to the registered address of such Person (provided that the holder of Debentures with an aggregate principal amount in excess of $5,000,000 shall, at the written election of such holder, be paid by wire transfer of immediately available funds) or (ii) by transfer to an account maintained by such Person located in the United States; provided, however, that payments to the Depositary will be made by wire transfer of immediately available funds to the account of the Depositary or its nominee.

Reference is made to the further provisions of this Debenture set forth on the reverse hereof, including, without limitation, provisions subordinating the payment of principal of and premium, if any, and interest on the Debentures to the prior payment in full of all Senior Debt, as defined in the Indenture, and provisions giving the holder of this Debenture the right to convert this Debenture into Common Stock of the Company on the terms and subject to the limitations referred to on the reverse hereof and as more fully specified in the Indenture. Such further provisions shall for all purposes have the same effect as though fully set forth at this place.

This Debenture shall be deemed to be a contract made under the laws of the State of New York, and for all purposes shall be construed in accordance with and governed by the laws of the State of New York, without regard to principles of conflicts of laws.

This Debenture shall not be valid or become obligatory for any purpose until the certificate of authentication hereon shall have been manually signed by the Trustee or a duly authorized authenticating agent under the Indenture.

MENTOR GRAPHICS CORPORATION

By:
Name: Walden C. Rhines
Title: Chairman and Chief Executive Officer

Attest:
Name: Dean M. Freed
Title: Secretary

This Debenture is one of a duly authorized issue of Debentures of the Company, designated as its Floating Rate Convertible Subordinated Debentures due 2023 (herein called the “Debentures”), limited to the aggregate principal amount of $100,000,000 (or $110,000,000 if the option set forth in Section 2 of the Purchase Agreement dated as of July 31, 2003 (as amended from time to time by the parties thereto) by and between the Company and the Initial Purchasers is exercised in full) all issued or to be issued under and pursuant to an Indenture dated as of August 6, 2003 (herein called the “Indenture”), between the Company and Wilmington Trust Company, as trustee (herein called the “Trustee”), to which Indenture and all indentures supplemental thereto reference is hereby made for a description of the rights, limitations of rights, obligations, duties and immunities thereunder of the Trustee, the Company and the holders of the Debentures.

In case an Event of Default (as defined in the Indenture) shall have occurred and be continuing, the principal of, premium, if any, and accrued interest (including Liquidated Damages (as defined in the Registration Rights Agreement), if any) on all Debentures may be declared due and payable, in the manner, with the effect and subject to the conditions provided in the Indenture.

The Indenture contains provisions permitting the Company and the Trustee, with the consent of the holders of not less than a majority in aggregate principal amount of the Debentures at the time outstanding, to execute supplemental indentures adding any provisions to or changing in any manner or eliminating any of the provisions of the Indenture or of any supplemental indenture or modifying in any manner the rights of the holders of the Debentures. Notwithstanding the foregoing, the written consent of each Debentureholders affected, an amendment, supplement or waiver, including a waiver pursuant to Section 7.07 of the Indenture, may not: (i) change the fixed maturity of any Debenture; (ii) reduce the rate or change the time of payment of interest or Liquidated Damages on any Debenture; (iii) reduce the principal amount of any Debenture or premium, if any, thereon, or reduce any amount payable on redemption or repurchase thereof or reduce the amount of Liquidated Damages payable thereon; (iv) impair the right of any Debentureholders to institute suit for the enforcement of any payment on a Debenture or with respect to the conversion of a Debenture; (v) make the principal of any Debenture or interest or premium, if any, or Liquidated Damages on any Debenture payable in any coin or currency other than that provided in the Debentures; (vi) modify the provisions of this Indenture with respect to the redemption of the Debentures in a manner adverse to the Debentureholders in any material respect; (vii) except as contemplated by Article 12 of the Indenture, change the obligation of the Company to repurchase any Debenture upon the happening of a Change of Control in a manner adverse to the Debentureholders; (viii) impair or adversely affect the right to convert the Debentures into Common Stock subject to the terms set forth herein without the consent of each Debentureholder so affected; (ix) alter the manner of calculation or rate of accrual of Liquidated Damages on any Debenture or extend the time for payment of such amount; or (x) reduce the percentage of Debentures, the holders of which are required to consent to any modification, amendment or supplemental indenture or the percentage of Debentures, or the holders of which are required for any other waiver under the Indenture.

Subject to the provisions of the Indenture, the holders of a majority in aggregate principal amount of the Debentures at the time outstanding may on behalf of the holders of all of the Debentures waive any past default or Event of Default under the Indenture and its consequences except a default in the payment of interest (including Liquidated Damages, if any) or any premium, if any, on, or the principal of, the Debentures, or a failure by the Company to convert any Debentures into Common Stock of the Company, or a default in the payment of the redemption price pursuant to Article 3 of the Indenture, or a default in respect of a covenant or provisions of the Indenture which under Article 11 of the Indenture cannot be modified without the consent of the holders of each or all Debentures then outstanding or affected thereby. Any such consent or waiver by the holder of this Debenture (unless revoked as provided in the Indenture) shall be conclusive and binding upon such holder and upon all future holders and owners of this Debenture and any Debentures which may be issued in exchange or substitution hereof, irrespective of whether or not any notation thereof is made upon this Debenture or such other Debentures.

The indebtedness evidenced by the Debentures is, to the extent and in the manner provided in the Indenture, expressly subordinated and subject in right of payment to the prior payment in full of all Senior Debt of the Company, whether outstanding at the date of the Indenture or thereafter incurred, and this Debenture is issued subject to the provisions of the Indenture with respect to such subordination. Each holder of this Debenture, by accepting the same, agrees to and shall be bound by such provisions and authorizes the Trustee on its behalf to take such action as may be necessary or appropriate to effectuate the subordination so provided and appoints the Trustee his attorney-in-fact for such purpose.

No reference herein to the Indenture and no provision of this Debenture or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of and any premium and interest (including Liquidated Damages, if any) on this Debenture at the place, at the respective times, at the rate and in the coin or currency herein prescribed.

Interest on the Debentures shall be computed using the actual number of days elapsed between the Reset Dates divided by 360.

The Debentures are issuable in fully registered form, without coupons, in denominations of $1,000 principal amount and any integral multiple of $1,000. At the office or agency of the Company referred to on the face hereof, and in the manner and subject to the limitations provided in the Indenture, without payment of any service charge but with payment of a sum sufficient to cover any tax, assessment or other governmental charge that may be imposed in connection with any registration or exchange of Debentures, Debentures may be exchanged for a like aggregate principal amount of Debentures of any other authorized denominations.

The Debentures will not be redeemable at the option of the Company prior to August 6, 2007. At any time on or after August 6, 2007, and prior to maturity, the Debentures may be redeemed at the option of the Company, in whole or in part, upon mailing a notice of such redemption not less than 20 days but not more than 60 days before the date fixed for redemption to the holders of Debentures at their last registered addresses, all as provided in the Indenture, at the following optional redemption prices (expressed as percentages of the principal amount), together in each case with accrued and unpaid interest (including Liquidated Damages (as defined in the Indenture), if any) to, but excluding, the date fixed for redemption:

and 100% on August 6, 2010 and at any time thereafter; provided, however, that, with the sole of exception of August 6, 2007, if the date fixed for redemption is on a February 6, May 6, August 6 or November 6, then the interest payable on such date shall be paid to the holder of record on the preceding January 21, April 21, July 21 or October 21, respectively. Debentures or portions of Debentures called for redemption will be convertible until the close of business on the Business Day prior to the date fixed for redemption.

The Company may not give notice of any redemption of the Debentures if a default in the payment of interest or premium, if any, on the Debentures has occurred and is continuing.

The Debentures are not subject to redemption through the operation of any sinking fund.

On August 6, 2010, August 6, 2013 and August 6, 2018, the holders of the Debentures shall have the right to require the Company to repurchase at such holder’s option all of such holders’ Debentures, or any portion thereof that is an integral multiple of $1,000 principal amount, on the Purchase Date (as defined in the Indenture) in cash at a price equal to 100% of the principal amount thereof, together with accrued interest (including Liquidated Damages, if any) to, but excluding the Purchase Date. The Company shall mail to all holders of record of the Debentures a notice of an upcoming Purchase Date not less than 20 Business Days prior to the Purchase Date. For a Debenture to be so repurchased at the option of the holder, the Company must receive at the office or agency of the Company maintained for that purpose in accordance with the terms of the Indenture, such Debenture with the Purchase Notice entitled “Option to Elect Repayment On Specific Dates” on the reverse thereof duly completed with such Debenture, duly endorsed for transfer, at any time from the opening of business on the date that is 20 Business Days prior to the Purchase Date until the close of business on the Purchase Date. Debentureholders may withdraw a Purchase Notice by delivering a written notice of withdrawal to the office or agency of the Company maintained for that purpose in accordance with the terms of the Indenture prior to the close of business on the Purchase Date. The repurchase of Debentures pursuant to this paragraph is subject to the further conditions set forth in the Indenture.

If a Change of Control occurs at any time prior to maturity, the holders of the Debentures shall have the right to require the Company to repurchase at such holder’s option all of such holders’ Debentures, or any portion thereof that is an integral multiple of $1,000 principal amount, on the Repurchase Date (as defined in the Indenture) in cash at a price equal to 100% of the principal amount thereof, together with accrued interest (including Liquidated Damages, if any) to, but excluding the Repurchase Date on the Repurchase Date that is no earlier than 25

days and no later than 35 days after the date of the Company Change of Control Notice; provided, however, that, if such Repurchase Date is February 6, May 6, August 6 or November 6, the interest payable on such date shall be paid to the holder of record of the Debentures on the preceding January 21, April 21, July 21 or October 21, respectively. The Company shall mail to all holders of record of the Debentures a notice of a Change of Control and of the repurchase right arising as a result thereof on or before the 30^th day after the occurrence of such Change of Control. For a Debenture to be so repurchased at the option of the holder, the Company must receive at the office or agency of the Company maintained for that purpose in accordance with the terms of the Indenture, such Debenture with the Repurchase Notice entitled “Option to Elect Repayment Upon a Change of Control” on the reverse thereof duly completed with such Debenture, duly endorsed for transfer, on or before the close of business on the Business Day that is five Business Days prior to the Repurchase Date. Debentureholders may withdraw a Purchase Notice by delivering a written notice of withdrawal to the office or agency of the Company maintained for that purpose in accordance with the terms of the Indenture prior to the close of business on the Business Day immediately preceding the Repurchase Date. The repurchase of Debentures pursuant to this paragraph is subject to the further conditions set forth in the Indenture.

Subject to the terms of the Indenture, the Debentureholder may convert the Debenture into shares of Common Stock at the Conversion Rate under the circumstances set forth in Sections 15.01 of the Indenture. A Debenture in respect of which a Debentureholder has delivered a Purchase Notice or a Repurchase Notice exercising the option of such Debentureholder to require the Company to purchase such Security may be converted only if such notice of exercise is withdrawn in accordance with the terms of the Indenture. The Conversion Rate for the Debentures on any Conversion Date shall be determined as set forth in the Indenture.

Only upon satisfaction of the conditions set forth in Article 15 of the Indenture, the holder hereof has the right, at its option, at any time after the original issuance of any Debentures through the close of business on the final maturity date of the Debentures, or, as to all or any portion hereof called for redemption, prior to the close of business on the Business Day immediately preceding the date fixed for redemption (unless the Company shall default in payment due upon redemption thereof), to convert the principal hereof or any portion of such principal which is $1,000 or an integral multiple thereof into that number of shares of the Company’s Common Stock (as such shares shall be constituted at the date of conversion) obtained by dividing the principal amount of this Debenture or portion thereof to be converted by the Conversion Rate of 42.7305 shares per $1,000 principal amount of Debenture (equivalent to a Conversion Price of approximately $23.40 per share), as may adjusted from time to time as provided in the Indenture, upon surrender of this Debenture, together with a conversion notice as provided in the Indenture (the form entitled “Conversion Notice” on the reverse hereof), to the Company at the office or agency of the Company maintained for that purpose in accordance with the terms of the Indenture, or at the option of such holder, the Corporate Trust Office, and, unless the shares issuable on conversion are to be issued in the same name as this Debenture, duly endorsed by, or accompanied by instruments of transfer in form satisfactory to the Company duly executed by, the holder or by his duly authorized attorney.

The Company shall satisfy its obligation with respect to conversion of the Debentures by delivering to Debentureholders the number of shares of Common Stock issuable upon conversion, together with a cash payment in lieu of any fractional shares as provided in Section 15.03 below. Any accrued and unpaid interest to the Conversion Date will be deemed cancelled, extinguished or forfeited upon conversion. The Company will not adjust the Conversion Rate to account for any accrued and unpaid interest or accrued or unpaid liquidated damages. If a Debenture is surrendered for conversion after the close of business on any record date for an interest payment but prior to the close of business on the Business Day immediately preceding the corresponding Interest Payment Date, Debentureholders will receive on the Interest Payment Date interest accrued on the Debentures, notwithstanding the conversion of the Debentures prior to the Interest Payment Date. At the time such Debentures are surrendered for conversion, Debentureholders shall pay to the Company an amount equal to the interest that has accrued and that will be paid on the Debentures being converted on the Interest Payment Date; provided, however, that no such payment shall be required if there shall exist at the time of conversion a default in the payment of interest on the Debentures. The preceding sentence shall not apply: (i) to Debentures called by the Company for redemption prior to August 11, 2007, (ii) to Debentures that are converted after being called by the Company for redemption after a record date for an interest payment date but prior to the corresponding interest payment date, or (iii) if a Debentureholder surrenders Debentures for conversion between the record date for the final Interest Payment Date and the opening of business on the final Interest Payment Date.

No fractional shares will be issued upon any conversion, but an adjustment and payment in cash will be made, as provided in the Indenture, in respect of any fraction of a share which would otherwise be issuable upon the surrender of any Debenture or Debentures for conversion. A Debenture in respect of which a holder is exercising its right to require a repurchase upon a Purchase Date or upon a Change of Control may be converted only if such holder withdraws its election to exercise such right in accordance with the terms of the Indenture. Any Debentures called for redemption, unless surrendered for conversion by the holders thereof on or before the close of business on the Business Day preceding the date fixed for redemption, may be deemed to be redeemed from the holders of such Debentures for an amount equal to the applicable redemption price, together with accrued but unpaid interest (including Liquidated Damages, if any) to (but excluding) the date fixed for redemption, by one or more investment banks or other purchasers who may agree with the Company (i) to purchase such Debentures from the holders thereof and convert them into shares of the Company’s Common Stock and (ii) to make payment for such Debentures as aforesaid to the Trustee in trust for the holders.

Upon due presentment for registration of transfer of this Debenture at the office or agency of the Company maintained for that purpose in accordance with the terms of the Indenture, a new Debenture or Debentures of authorized denominations for an equal aggregate principal amount will be issued to the transferee in exchange thereof; subject to the limitations provided in the Indenture, without charge except for any tax, assessment or other governmental charge imposed in connection therewith.

The Company, the Trustee, any authenticating agent, any paying agent, any conversion agent and any Debenture registrar may deem and treat the registered holder hereof as the absolute owner of this Debenture (whether or not this Debenture shall be overdue and notwithstanding any notation of ownership or other writing hereon made by anyone other than

the Company or any Debenture registrar) for the purpose of receiving payment hereof, or on account hereof, for the conversion hereof and for all other purposes, and neither the Company nor the Trustee nor any other authenticating agent nor any paying agent nor other conversion agent nor any Debenture registrar shall be affected by any notice to the contrary. All payments made to or upon the order of such registered holder shall, to the extent of the sum or sums paid, satisfy and discharge liability for monies payable on this Debenture.

No recourse for the payment of the principal of or any premium or interest on this Debenture, or for any claim based hereon or otherwise in respect hereof, and no recourse under or upon any obligation, covenant or agreement of the Company in the Indenture or any supplemental indenture or in any Debenture, or because of the creation of any indebtedness represented thereby, shall be had against any incorporator, stockholder, employee, agent, officer or director or subsidiary, as such, past, present or future, of the Company or of any successor corporation, either directly or through the Company or any successor corporation, whether by virtue of any constitution, statute or rule of law or by the enforcement of any assessment or penalty or otherwise, all such liability being, by acceptance hereof and as part of the consideration for the issue hereof, expressly waived and released.

This Debenture shall be deemed to be a contract made under the laws of New York, and for all purposes shall be construed in accordance with the laws of New York, without regard to principles of conflicts of laws.

Terms used in this Debenture and defined in the Indenture are used herein as therein defined.

The following abbreviations, when used in the inscription of the face of this Debenture, shall be construed as though they were written out in full according to applicable laws or regulations.

The undersigned registered owner of this Debenture hereby irrevocably exercises the option to convert this Debenture, or the portion thereof (which is $1,000 or an integral multiple thereof) below designated, into shares of Common Stock of Mentor Graphics Corporation in accordance with the terms of the Indenture referred to in this Debenture, and directs that the shares issuable and deliverable upon such conversion, together with any check in payment for fractional shares and any Debentures representing any unconverted principal amount hereof, be issued and delivered to the registered holder hereof unless a different name has been indicated below. If shares or any portion of this Debenture not converted are to be issued in the name of a person other than the undersigned, the undersigned will provide the appropriate information below and pay all transfer taxes payable with respect thereto. Any amount required to be paid by the undersigned on account of interest accompanies this Debenture.



				Signature(s)

				Signature(s) must be guaranteed by an “eligible guarantor institution” meeting the requirements of the Debenture registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program (“STAMP”) or such other “signature guarantee program” as may be determined by the Debenture registrar in addition to, or in substitution for, STAMP, all in accordance with the Securities Exchange Act of 1934, as amended.


				Signature Guarantee

Fill in the registration of shares of Common Stock if to be issued, and Debentures if to be delivered, other than to and in the name of the registered holder:

The undersigned registered owner of this Debenture hereby irrevocably acknowledges receipt of a notice from Mentor Graphics Corporation (the “Company”) as to the occurrence of a Change of Control with respect to the Company and requests and instructs the Company to repay the entire principal amount of this Debenture, or the portion thereof (which is $1,000 or an integral multiple thereof) below designated, in accordance with the terms of the Indenture referred to in this Debenture at the price of 100% of such entire principal amount or portion thereof, together with accrued interest to, but excluding, such repayment date, to the registered holder hereof.



						Signature(s)

						NOTICE: The above signatures of the holder(s) hereof must correspond with the name as written upon the face of the Debenture in every particular without alteration or enlargement or any change whatever.

Principal amount to be repaid (if less than all):

$

Social Security or Other Tax Identification Number:

Pursuant to its rights under Section 3.05 of the Indenture referred to in this Debenture, the undersigned registered owner of this Debenture hereby requests and instructs Mentor Graphics Corporation (the “Company”) to repay the entire principal amount of this Debenture, or the portion thereof (which is $1,000 or an integral multiple thereof) below designated, in accordance with the terms of the Indenture at the price of 100% of such entire principal amount or portion thereof, together with accrued interest to, but excluding, such repayment date, to the registered holder hereof.



						Signature(s)

						NOTICE: The above signatures of the holder(s) hereof must correspond with the name as written upon the face of the Debenture in every particular without alteration or enlargement or any change whatever.

Principal amount to be repaid (if less than all):

$

Social Security or Other Tax Identification Number:

For value received _ hereby sell(s) assign(s) and transfer(s) unto (Please insert social security or other Taxpayer Identification Number of assignee) the within Debenture, and hereby irrevocably constitutes and appoints _ attorney to transfer said Debenture on the books of the Company, with full power of substitution in the premises.

In connection with any transfer of the Debenture within the United States or to, or for the account of, U.S. persons and within the period prior to the expiration of the holding period applicable to sales thereof under Rule 144(k) under the Securities Act (or any successor provision) (other than any transfer pursuant to a registration statement that has been declared effective under the Securities Act), the undersigned confirms that such Debenture is being transferred:

and unless the box below is checked, the undersigned confirms that such Debenture is not being transferred to an “affiliate” of the Company as defined in Rule 144 under the Securities Act of 1933, as amended (an “Affiliate”).

NOTICE: The signature of the conversion notice, the option to elect repayment upon a Change of Control or the assignment must correspond with the name as written upon the face of the Debenture in every particular without alteration or enlargement or any change whatever.

In connection with our proposed purchase of Floating Rate Convertible Subordinated Debentures due 2023 (the “Debentures”) of Mentor Graphics Corporation, an Oregon corporation (the “Company”) we confirm that:

(i) we are an “accredited investor” within the meaning of Rule 501(a)(1), (2) or (3) under the Securities Act of 1933, as amended (the “Securities Act”), or an entity in which all of the equity owners are accredited investors within the meaning of Rule 501(a)(1), (2) or (3) under the Securities Act (an “Institutional Accredited Investor”);

(ii) (A) any purchase of Debentures by us will be for our own account or for the account of one or more other Institutional Accredited Investors or as fiduciary for the account of one or more trusts, each of which is an “accredited investor” within the meaning of Rule 501 (a)(7) under the Securities Act and for each of which we exercise sole investment discretion or (B) we are a “bank,” within the meaning of Section 3(a)(2) of the Securities Act, or a “savings and loan association” or other institution described in Section 3(a)(5)(A) of the Securities Act that is acquiring Debentures as fiduciary for the account of one or more institutions for which we exercise sole investment discretion;

(iii) the event that we purchase any Debentures, we will acquire Debentures having a minimum purchase price of not less than $100,000 for our own account or for any separate account for which we are acting;

(iv) we have such knowledge and experience in financial and business matters that we are capable of evaluating the merits and risks of purchasing Debentures; and

(v) we are not acquiring Debentures with a view to distribution thereof or with any present intention of offering or selling Debentures or the Common Stock of the Company issuable upon conversion thereof, except as permitted below; provided that the disposition of our property and property of any accounts for which we are acting as fiduciary shall remain at all times within our control.

We understand that the Debentures are being offered in a transaction not involving any public offering within the United States within the meaning of the Securities Act and that the Debentures and the Common Stock of the Company issuable upon conversion thereof have not been registered under the Securities Act, and we agree, on our own behalf and on behalf of each account for which we acquire any Debentures, that if in the future we decide to resell or otherwise transfer such Debentures or the Common Stock of the Company issuable upon conversion thereof, such Debentures or Common Stock of the Company may be resold or otherwise transferred only (i) to the Company or any subsidiary thereof, (ii) a “qualified institutional buyer” (as defined in Rule 144A under the Securities Act) in compliance with Rule 144A under the Securities Act, (iii) pursuant to exemption from registration provided by Rule 144 under the Securities Act; (iv) to an institutional investor that is an “accredited investor” within the meaning of rule 501(a)(1), (2), (3) or (7) of Regulation D under the Securities Act pursuant to an exemption from registration under the Securities Act (if available), or (v) pursuant to a registration statement that has been declared effective under the Securities Act and which continues to be effective at the time of such transfer, and in each case, in accordance with any applicable securities law of any state of the United States and in accordance with the legends set forth on the Debentures or the Common Stock of the Company issuable upon conversion thereof. We further agree to provide any person purchasing any of the Debentures or the Common Stock of the Company issuable upon conversion thereof (other than pursuant to clause (iii) or (v) above) from us a notice advising such purchaser that resales of such securities are restricted as stated herein. We understand that the Trustee and transfer agent for the Debentures and the Common Stock of the Company will not be required to accept for registration of transfer any Debentures or any Common Stock of the Company issued upon conversion of the Debentures, except upon presentation of evidence satisfactory to the Company that the foregoing restrictions on transfer have been complied with. We further understand that any Debentures and any Common Stock of the Company issued upon conversion of the Debentures will be in the form of definitive physical certificates and that such certificates will bear a legend reflecting the substance of this paragraph other than certificates transferred pursuant to (iii) or (v) above.

The Company and the Trustee and their respective counsel are entitled to rely upon this letter and are irrevocably authorized to produce this letter or a copy hereof to any interested party in any administrative or legal proceeding or official inquiry with respect to the matters covered hereby.

THIS LETTER SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE INTERNAL LAWS OF THE STATE OF NEW YORK.

(Name of Purchaser)

By:
Name:
Title:

Address:

Section 8.08	Conflicting Interests of Trustee	52
Section 8.09	Eligibility of Trustee	52
Section 8.10	Resignation Or Removal Of Trustee	52
Section 8.11	Acceptance by Successor Trustee	54
Section 8.12	Succession by Merger, Etc	54
Section 8.13	Preferential Collection of Claims	55
Section 8.14	Trustee’s Application for Instructions from the Company	55

ARTICLE 9. THE DEBENTUREHOLDERS		55

Section 9.01	Action by Debentureholders	55
Section 9.02	Proof of Execution by Debentureholders	56
Section 9.03	Who Are Deemed Absolute Owners	56
Section 9.04	Company-owned Debentures Disregarded	56
Section 9.05	Revocation of Consents; Future Holders Bound	56

ARTICLE 10. MEETINGS OF DEBENTUREHOLDERS		57

Section 10.01	Purpose of Meetings	57
Section 10.02	Call of Meetings by Trustee	57
Section 10.03	Call of Meetings by Company or Debentureholders	57
Section 10.04	Qualifications for Voting	58
Section 10.05	Regulations	58
Section 10.06	Voting	58
Section 10.07	No Delay of Rights by Meeting	59

ARTICLE 11. SUPPLEMENTAL INDENTURES		59

Section 11.01	Supplemental Indentures Without Consent of Debentureholders	59
Section 11.02	Supplemental Indenture with Consent of Debentureholders	61
Section 11.03	Effect of Supplemental Indenture	62
Section 11.04	Notation on Debentures	62
Section 11.05	Evidence of Compliance of Supplemental Indenture to be Furnished to Trustee	62

ARTICLE 12. CONSOLIDATION, MERGER, SALE, CONVEYANCE AND LEASE		63

Section 12.01	Company May Consolidate, Etc, on Certain Terms	63
Section 12.02	Successor Corporation to Be Substituted	63
Section 12.03	Opinion of Counsel to be Given Trustee	64

ARTICLE 13. SATISFACTION AND DISCHARGE OF INDENTURE		64

Section 13.01	Discharge of Indenture	64
Section 13.02	Deposited Monies to Be Held in Trust by Trustee	64
Section 13.03	Paying Agent to Repay Monies Held	65
Section 13.04	Return of Unclaimed Monies	65

Section 13.05	Reinstatement	65

ARTICLE 14. IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS AND DIRECTORS		65

Section 14.01	Indenture and Debentures Solely Corporate Obligations	65

ARTICLE 15. CONVERSION OF DEBENTURES		66

Section 15.01	Right to Convert and Conversion Rate	66
Section 15.02	Exercise of Conversion Privilege; Issuance of Common Stock on Conversion; No Adjustment for Interest or Dividends	69
Section 15.03	Cash Payments in Lieu of Fractional Shares	71
Section 15.04	Conversion Rate	71
Section 15.05	Adjustment of Conversion Rate	71
Section 15.06	Effect of Reclassification, Consolidation, Merger or Sale	80
Section 15.07	Taxes on Shares Issued	80
Section 15.08	Reservation of Shares; Shares to Be Fully Paid; Compliance with Governmental Requirements; Listing of Common Stock	81
Section 15.09	Responsibility of Trustee	81
Section 15.10	Notice To Holders Prior To Certain Actions	82

ARTICLE 16. MISCELLANEOUS PROVISIONS		83

Section 16.01	Provisions Binding on Company’s Successors	83
Section 16.02	Official Acts by Successor Corporation	83
Section 16.03	Addresses for Notices, Etc	83
Section 16.04	Governing Law	83
Section 16.05	Evidence of Compliance with Conditions Precedent; Certificates to Trustee	84
Section 16.06	Legal Holidays	84
Section 16.07	Trust Indenture Act	84
Section 16.08	No Security Interest Created	84
Section 16.09	Benefits of Indenture	84
Section 16.10	Table of Contents, Headings, Etc	85
Section 16.11	Authenticating Agent	85
Section 16.12	Execution in Counterparts	86
Section 16.13	Severability	86

TRUST INDENTURE ACT SECTION		INDENTURE SECTION
Section 310 (a)(1)		8.9
(a)(2)		8.9
(a)(3)		N.A.
(a)(4)		N.A.
(a)(5)		8.9
(b)		8.8; 8.9; 8.10; 8.11
Section 311 (a)		8.13
(b)		8.13
(b)(2)		8.13
Section 312 (a)		6.1; 6.2(a)
(b)		6.2(b)
(c)		6.2(c)
Section 313 (a)		6.3(a)
(b)		6.3(a)
(c)		6.3(a)
(d)		6.3(b)
Section 314 (a)		6.4
(b)		N.A.
(c)(1)		16.5
(c)(2)		16.5
(c)(3)		N.A.
(d)		N.A.
(e)		16.5
Section 315 (a)		8.1
(b)		7.8
(c)		8.1
(d)		8.1
(d)(1)		8.1 (a)
(d)(2)		8.1(b)
(d)(3)		8.1(c)
(e)		7.9
Section 316 (a)		7.7
(a)(1)(A)		7.7
(a)(1)(B)		7.7
(a)(2)		N.A.
(b)		7.4
Section 317 (a)(1)		7.5
(a)(2)		7.5
(b)		5.4
Section 318 (a)		16.7

Period	Redemption Price

Beginning on August 6, 2007 and ending on August 5, 2008	102.42	%

Beginning on August 6, 2008 and ending on August 5, 2009	101.61	%

Beginning on August 6, 2009 and ending on August 5, 2010	100.81	%

Period	Redemption Price
Beginning on August 6, 2007 and ending on August 5, 2008	102.42	%
Beginning on August 6, 2008 and ending on August 5, 2009	101.61	%
Beginning on August 6, 2009 and ending on August 5, 2010	100.81	%

			Page

ARTICLE 1. DEFINITIONS			1

	Section 1.01	Definitions	1

ARTICLE 2. ISSUE, DESCRIPTION, EXECUTION, REGISTRATION AND EXCHANGE OF DEBENTURES			10

	Section 2.01	Designation Amount and Issue of Debentures	10
	Section 2.02	Form of Debentures	11
	Section 2.03	Date and Denomination of Debentures; Payments of Interest	11
	Section 2.04	Execution of Debentures	13
	Section 2.05	Exchange and Registration of Transfer Debentures; Restrictions on Transfer; Depositary	13
	Section 2.06	Mutilated, Destroyed, Lost or Stolen Debentures	20
	Section 2.07	Temporary Debentures	21
	Section 2.08	Cancellation of Debentures Paid, Etc	21
	Section 2.09	CUSIP Numbers	21

ARTICLE 3. REDEMPTION OF DEBENTURES			22

	Section 3.01	Optional Redemption by the Company	22
	Section 3.02	Notice of Redemptions; Selection of Debentures	23
	Section 3.03	Payment of Debentures Called for Redemption	24
	Section 3.04	Conversion Arrangement on Call for Redemption	25
	Section 3.05	Redemption at Option of Debentureholders on Specific Dates	26
	Section 3.06	Repurchase at Option of Debentureholders upon a Change of Control	28

ARTICLE 4. SUBORDINATION OF DEBENTURES			30

	Section 4.01	Agreement of Subordination	30
	Section 4.02	Payments to Debentureholders	31
	Section 4.03	Subrogation of Debentures	33
	Section 4.04	Authorization to Effect Subordination	34
	Section 4.05	Notice to Trustee	35
	Section 4.06	Trustee’s Relation to Senior Debt	35
	Section 4.07	No Impairment of Subordination	36
	Section 4.08	Certain Conversions Not Deemed Payment	36
	Section 4.09	Article Applicable to Paying Agents	36
	Section 4.10	Senior Debt Entitled to Rely	37

	Section 4.11	Reliance on Judicial Order or Certificate of Liquidating Agent	37

ARTICLE 5. PARTICULAR COVENANTS OF THE COMPANY			37

	Section 5.01	Payment of Principal, Premium and Interest	37
	Section 5.02	Maintenance of Office or Agency	38
	Section 5.03	Appointments to Fill Vacancies in Trustee’s Office	38
	Section 5.04	Provisions As To Paying Agent	38
	Section 5.05	Existence	39
	Section 5.06	Maintenance of Properties	39
	Section 5.07	Payment of Taxes and Other Claims	39
	Section 5.08	Rule 144A Information Requirement	40
	Section 5.09	Stay, Extension and Usury Laws	40
	Section 5.10	Compliance Certificate	40

ARTICLE 6. DEBENTUREHOLDERS’ LIST AND REPORTS BY THE COMPANY AND THE TRUSTEE			41

	Section 6.01	Debentureholders’ Lists	41
	Section 6.02	Preservation and Disclosure of Lists	41
	Section 6.03	Reports by Trustee	41
	Section 6.04	Reports by Company	42

ARTICLE 7. REMEDIES OF THE TRUSTEE AND DEBENTUREHOLDERS ON AN EVENT OF DEFAULT			42

	Section 7.01	Events of Default	42
	Section 7.02	Payments of Debentures on Default; Suit Therefor	44
	Section 7.03	Application of Monies Collected by Trustee	46
	Section 7.04	Proceedings by Debentureholders	46
	Section 7.05	Proceedings by Trustee	47
	Section 7.06	Remedies Cumulative and Continuing	47
	Section 7.07	Direction of Proceedings and Waiver of Defaults by Majority of Debentureholders	48
	Section 7.08	Notice of Defaults	48
	Section 7.09	Undertaking to Pay Costs	48

ARTICLE 8. THE TRUSTEE			49

	Section 8.01	Duties and Responsibilities of Trustee	49
	Section 8.02	Reliance on Documents, Opinions, Etc	50
	Section 8.03	No Responsibility for Recitals, Etc	51
	Section 8.04	Trustee, Paying Agents, Conversion Agents or Registrar May Own Debentures	51
	Section 8.05	Monies to Be Held in Trust	51
	Section 8.06	Compensation and Expenses of Trustee	51
	Section 8.07	Officers’ Certificate as Evidence	52

TEN COM - as tenants in common	UNIF GIFT MIN ACT -
		Custodian

TEN ENT -as tenant by the entireties		(Cust) (Minor)

JT TEN -as joint tenants with right under
Uniform Gifts to Minors Act of survivorship
and not asunder Uniform Gifts to(state) Minors			(state)
Act tenants in common

Additional abbreviations may also be used though not in the above list.

Dated:




				Signature(s)

				Signature(s) must be guaranteed by an “eligible guarantor institution” meeting the requirements of the Debenture registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program (“STAMP”) or such other “signature guarantee program” as may be determined by the Debenture registrar in addition to, or in substitution for, STAMP, all in accordance with the Securities Exchange Act of 1934, as amended.


				Signature Guarantee

No.:		CUSIP:

		$