Exhibit 4.3

SILICON GRAPHICS, INC.  51/4% Senior Convertible Notes due 2004    INDENTURE  Dated as of September 1, 1997    STATE STREET BANK AND TRUST
COMPANY OF CALIFORNIA,  N.A., TRUSTEE

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SILICON GRAPHICS, INC.  Reconciliation and tie between  Trust Indenture Act of 1939 and  Indenture, dated as of September 1, 1997

|Trust Indenture
Act Section |  | Indenture Section
|--------------------------- |  | -----------------
|§310(a)(1)                  |  | 7.10             
|(a)(2)                      |  | 7.10             
|(a)(3)                      |  | Not Applicable   
|(a)(4)                      |  | Not Applicable   
|(b)                         |  | 7.06, 7.08       
|§311(a)                     |  | 7.11             
|(b)                         |  | 7.11             
|(c)                         |  | Not Applicable   
|§312(a)                     |  | 2.05, 2.14       
|(b)                         |  | 2.14(b), 11.03   
|(c)                         |  | 2.14(c), 11.03   
|§313(a)                     |  | 7.12(a)          
|(b)                         |  | 7.12(a)          
|(c)                         |  | 7.12(a)          
|(d)                         |  | 7.12(b)          
|§314(a)                     |  | 4.02             
|(b)                         |  | Not Applicable   
|(c)(1)                      |  | 11.04            
|(c)(2)                      |  | 11.04            
|(c)(3)                      |  | Not Applicable   
|(d)                         |  | Not Applicable   
|(e)                         |  | 11.04            
|(f)                         |  | Not Applicable   
|§315(a)                     |  | 7.01             
|(b)                         |  | 7.05, 7.12(a)    
|(c)                         |  | 7.01             
|(d)                         |  | 6.11             
|§316(a)(1)(A)               |  | 6.02             
|(a)(1)(B)                   |  | 6.04             
|(a)(2)                      |  | Not Applicable   
|(b)                         |  | 6.07             
|(c)                         |  | Not Applicable   
|§317(a)(1)                  |  | 6.08             
|(a)(2)                      |  | 6.09             
|(b)                         |  | 3.03             
|§318(a)                     |  | 11.1             

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

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TABLE OF CONTENTS1

|                                                     |  |                                                                 |  | PAGE
|---------------------------------------------------- |  | --------------------------------------------------------------- |  | ----
|ARTICLE 1
DEFINITIONS AND INCORPORATION BY REFERENCE
|Section 1.01.                                        |  | Definitions                                                     |  | 1   
|Section 1.02.                                        |  | Other Definitions                                               |  | 5   
|Section 1.03.                                        |  | Incorporation by Reference of TIA                               |  | 5   
|Section 1.04.                                        |  | Rules of Construction                                           |  | 5   
|ARTICLE 2
THE SECURITIES                            
|Section 2.01.                                        |  | Form and Dating                                                 |  | 5   
|Section 2.02.                                        |  | Execution and Authentication                                    |  | 6   
|Section 2.03.                                        |  | Registrar, Paying Agent and Conversion Agent                    |  | 6   
|Section 2.04.                                        |  | Paying Agent to Hold Money and Securities in Trust              |  | 6   
|Section 2.05.                                        |  | Securityholder Lists                                            |  | 7   
|Section 2.06.                                        |  | Exchange and Registration of Transfer of Securities; Depositary |  | 7   
|Section 2.07.                                        |  | Replacement Securities                                          |  | 8   
|Section 2.08.                                        |  | Outstanding Securities; Determinations of Holders' Action       |  | 9   
|Section 2.09.                                        |  | Temporary Securities                                            |  | 9   
|Section 2.10.                                        |  | Cancellation                                                    |  | 10  
|Section 2.11.                                        |  | Persons Deemed Owners                                           |  | 10  
|Section 2.12.                                        |  | Payment of Interest; Interest Rights Preserved                  |  | 10  
|Section 2.13.                                        |  | Computation of Interest                                         |  | 11  
|Section 2.14.                                        |  | Preservation of Information; Communications to Holders          |  | 11  
|ARTICLE 3
REDEMPTION                                
|Section 3.01.                                        |  | Right to Redeem; Notices to Trustee                             |  | 11  
|Section 3.02.                                        |  | Selection of Securities to be Redeemed                          |  | 12  
|Section 3.03.                                        |  | Notice of Redemption                                            |  | 12  
|Section 3.04.                                        |  | Effect of Notice of Redemption                                  |  | 12  
|Section 3.05.                                        |  | Deposit of Redemption Price                                     |  | 13  
|Section 3.06.                                        |  | Securities Redeemed in Part                                     |  | 13  
|Section 3.07.                                        |  | Conversion Arrangement on Call for Redemption                   |  | 13  
|Section 3.08.                                        |  | Redemption at Option of the Holder upon a Fundamental Change    |  | 14  
|ARTICLE 4
COVENANTS                                 
|Section 4.01.                                        |  | Payment of Securities                                           |  | 16  
|Section 4.02.                                        |  | SEC Reports                                                     |  | 16  
|Section 4.03.                                        |  | Compliance Certificate                                          |  | 16  
|Section 4.04.                                        |  | Further Instruments and Acts                                    |  | 16  
|Section 4.05.                                        |  | Maintenance of Office or Agency                                 |  | 16  

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|ARTICLE 5
SUCCESSOR CORPORATION 
|--------------------------------
|Section 5.01.                   
|ARTICLE 6
DEFAULTS AND REMEDIES 
|Section 6.01.                   
|Section 6.02.                   
|Section 6.03.                   
|Section 6.04.                   
|Section 6.05.                   
|Section 6.06.                   
|Section 6.07.                   
|Section 6.08.                   
|Section 6.09.                   
|Section 6.10.                   
|Section 6.11.                   
|Section 6.12.                   
|ARTICLE 7
TRUSTEE               
|Section 7.01.                   
|Section 7.02.                   
|Section 7.03.                   
|Section 7.04.                   
|Section 7.05.                   
|Section 7.06.                   
|Section 7.07.                   
|Section 7.08.                   
|Section 7.09.                   
|Section 7.10.                   
|Section 7.11.                   
|Section 7.12.                   
|ARTICLE 8
DISCHARGE OF INDENTURE
|Section 8.01.                   
|Section 8.02.                   
|ARTICLE 9
AMENDMENTS            
|Section 9.01.                   
|Section 9.02.                   
|Section 9.03.                   
|Section 9.04.                   
|Section 9.05.                   
|Section 9.06.                   
|Section 9.07.                   

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|ARTICLE 10
CONVERSION      
|---------------------------
|Section 10.01.             
|Section 10.02.             
|Section 10.03.             
|Section 10.04.             
|Section 10.05.             
|Section 10.06.             
|Section 10.07.             
|Section 10.08.             
|Section 10.09.             
|Section 10.10.             
|Section 10.11.             
|Section 10.12.             
|Section 10.13.             
|Section 10.14.             
|Section 10.15.             
|Section 10.16.             
|Section 10.17.             
|Section 10.18.             
|Section 10.19.             
|Section 10.20.             
|ARTICLE 11
MISCELLANEOUS   
|Section 11.01.             
|Section 11.02.             
|Section 11.03.             
|Section 11.04.             
|Section 11.05.             
|Section 11.06.             
|Section 11.07.             
|Section 11.08.             
|Section 11.09.             
|Section 11.10.             
|Section 11.11.             
|Section 11.12.             
|EXHIBIT A Form of Security

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INDENTURE, dated as of September 1, 1997, between SILICON GRAPHICS, INC., a Delaware corporation (the "Company"), and STATE STREET BANK AND TRUST COMPANY OF CALIFORNIA,
N.A., a national banking association organized and existing under the laws of the United States of America (the "Trustee").

Each
party agrees as follows for the benefit of the other party and for the equal and ratable benefit of the Holders of the Company's 51/4% Senior Convertible Notes due
2004 (the "Securities"):

ARTICLE 1  DEFINITIONS AND INCORPORATION BY REFERENCE

Section 1.01.Definitions.

"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.

"Applicable
Price" means (i) in the event of a Fundamental Change in which the holders of the Common Stock receive only cash, the amount of cash received by the holder of one
share of Common Stock and (ii) in the event of any other Fundamental Change, the average of the last reported sales price for the Common Stock (determined as set forth in the definition of
Current Market Price) during the ten Trading Days prior to the record date for the determination of the holders of Common Stock entitled to receive cash, securities, property or other assets in
connection with such Fundamental Change, or, if there is no such record date, the date upon which the holders of Common Stock shall have the right to receive such cash, securities, property or other
assets in connection with a Fundamental Change.

"Board
of Directors" means either the board of directors of the Company or any duly authorized committee of such board.

"Business
Day" means each day of the year on which banking institutions are not required or authorized to close in The City of New York or at the principal corporate trust office of the
Trustee.

"Closing
Price" means with respect to any securities on any day the closing sale price regular way on such day or, in case no such sale takes place on such day, the average of the
reported closing bid and asked prices, regular way, in each case on the New York Stock Exchange, or, if such security is not listed or admitted to trading on such Exchange, on the principal national
security exchange or quotation system on which such security is quoted or listed or admitted to trading, or, if not quoted or listed or admitted to trading on any national securities exchange or
quotation system, the average of the closing bid and asked prices of such security on the over-the-counter market on the day in question as reported by the National Quotation
Bureau Incorporated, or a similar generally accepted reporting service, or if not so available, in such manner as furnished by any New York Stock Exchange member firm selected from time to time by the
Board of Directors for that purpose, or 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.

"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 10.14, however, shares issuable on conversion of the
Securities shall include only shares of Common Stock, par value $.001 per share, of the Company as it exists on the date of this Indenture 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 that if at any time there shall be more than one such

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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 party named as the "Company" in the first paragraph of this Indenture until a successor replaces it pursuant to the applicable provisions of this Indenture and,
thereafter, shall mean such successor. The foregoing sentence shall likewise apply to any subsequent such successor or successors.

"Company
Request" or "Company Order" means a written request or order signed in the name of the Company by its Chairman of the Board, a Vice Chairman, its President, a Senior Vice
President or a Vice President, and by its Treasurer, an Assistant Treasurer, its Secretary or an Assistant Secretary, and delivered to the Trustee.

"Conversion
Price" has the meaning specified in Section 10.01.

"Current
Market Price" per share of Common Stock at any date shall be the average of the last reported sale prices for the ten consecutive Trading Days preceding the day before the
record date with respect to any distribution, issuance or other event requiring such computation. The last reported sale price for each day shall be (i) the last reported sale price of Common
Stock on the New York Stock Exchange, or, if such security is not listed or admitted to trading on such Exchange, on the principal national security exchange on which such security is listed, or on
the Nasdaq National Market or any similar system of automated dissemination of quotations of securities prices then in common use, if so quoted, or (ii) if not quoted as described in
clause (i), the mean between the high bid and low asked quotations for Common Stock as reported by the National Quotation Bureau Incorporated if at least two securities dealers have inserted
both bid and asked quotations for the Common Stock on at least 5 of the 10 preceding days, or (iii) if the Common Stock is listed or admitted for trading on any national securities exchange,
the last sale price, or the closing bid price if no sale occurred, of the Common Stock on the principal securities exchange on which the Common Stock is listed. If the Common Stock is quoted on a
national securities or central market system, in lieu of a market or quotation system described above, the last reported sale price shall be determined in the manner set forth in clause (ii) of
the preceding sentence if bid and asked quotations are reported but actual transactions are not, and in the manner set forth in clause (iii) of the preceding sentence if actual transactions are
reported. If none of the conditions set forth above is met, the last reported sale price of Common Stock on any day or the average of such last reported sale prices for any period shall be the fair
market value of the Common Stock as determined by a member firm of the New York Stock Exchange, Inc. selected by the Company.

"Custodian"
means State Street Bank and Trust Company of California, N.A., as custodian with respect to any Global Security, or any successor.

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

"Defaulted
Interest" has the meaning specified in Section 2.12.

"Depositary"
means, with respect to the Securities issuable or issued in whole or in part in global form, the person specified in Section 2.06 as the Depositary with respect to
the Securities, 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.

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

"Fundamental
Change" means the occurrence of any transaction or event in connection with which all or substantially all the Common Stock shall be exchanged for, converted into, acquired
for or

2

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constitute
solely the right to receive (whether by means of an exchange offer, liquidation, tender offer, consolidation, merger, combination, reclassification, recapitalization or otherwise)
consideration which is not all or substantially all common stock listed (or, upon consummation of such transaction or event, will be listed) on a United States national securities exchange or approved
for quotation in the Nasdaq National Market or any similar system of automated dissemination of quotations of securities prices.

"Global
Security" means a Security that is registered in the Security Register in the name of the Depository or a nominee thereof.

"Holder"
or "Securityholder" means a Person in whose name a Security is registered on the Registrar's books.

"Indenture"
means this Indenture, as amended or supplemented from time to time in accordance with the terms hereof.

"Interest
Payment Date" means the Stated Maturity of an installment of interest on the Securities.

"Interest
Period" shall have the meaning set forth in Section 10.02.

"Maturity"
when used with respect to any Security, means the date on which the principal of such Security becomes due and payable as therein or herein provided, whether at the Stated
Maturity or by declaration of acceleration, call for redemption, redemption upon a Fundamental Change or otherwise.

"Officer"
means the Chairman of the Board, any Vice Chairman, the President, any Senior Vice President, any Vice President, the Treasurer or the Secretary or any Assistant Treasurer or
Assistant Secretary of the Company.

"Officers'
Certificate" means a written certificate containing the information specified in Sections 11.04 and 11.05, signed in the name of the Company by its Chairman of the Board, a
Vice Chairman, its President, a Senior Vice President or a Vice President, and by its Treasurer, an Assistant Treasurer, its Secretary or an Assistant Secretary, and delivered to the Trustee.

"Opinion
of Counsel" means a written opinion containing the information specified in Sections 11.04 and 11.05, from legal counsel who is acceptable to the Trustee. The counsel may be an
employee of, or counsel to, the Company or the Trustee.

"Person"
means any individual, corporation, partnership, joint venture, association, joint-stock company, trust, unincorporated organization, or government or any agency or political
subdivision thereof.

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

"Reference
Market Price" shall initially mean $18.33 and in the event of any adjustment to the Conversion Price pursuant to Article 10, the Reference Market Price shall be
adjusted to equal the initial Reference Market Price multiplied by a fraction the numerator of which is the Conversion Price specified in the form of Security attached as Exhibit A hereto
(without regard to any adjustment thereto) and the denominator of which is the Conversion Price following such adjustment.

"Redemption
Date" shall mean a date specified for redemption of the Securities (other than redemption upon a Fundamental Change at the option of the Securityholder) in accordance with
the terms of the Securities and Section 3.01 of this Indenture.

"Redemption
Price" shall have the meaning set forth in paragraph 5 of the Securities.

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"Regular
Record Date" for the interest payable on any Interest Payment Date means the February 15 or August 15 (whether or not a Business Day), as the case may be, next
preceding such Interest Payment Date.

"Rights
Agreement" means that certain Amended and Restated Preferred Shares Rights Agreement, dated as of May 6, 1992, between the Company and State Street Bank and Trust Company
of California, N.A., as successor rights agent thereunder, as amended from time to time.

"Rights"
shall mean "Rights" as such term is defined in the Rights Agreement.

"SEC"
means the Securities and Exchange Commission.

"Securities"
means any of the Company's 51/4% Senior Convertible Notes due 2004, as amended or supplemented from time to time, issued under this Indenture.

"Securities
Act" means the Securities Act of 1933, as amended, and the rules and regulations of the SEC promulgated thereunder.

"Securityholder"
or "Holder" means a person in whose name a Security is registered on the Registrar's books.

"Security
Register" has the meaning specified in Section 2.05.

"Special
Record Date" for the payment of any Defaulted Interest means a date fixed by the Trustee pursuant to Section 2.12.

"Stated
Maturity" when used with respect to any Security or any installment of interest thereon, means the date specified in such Security as the fixed date on which the principal of
such Security or such installment of interest is due and payable.

"Subsidiary"
means a corporation of which a majority of the capital stock (which for purposes of this definition means any and all shares, interests, rights to purchase, warrants,
options, participations or other equivalents of or interests in (however designated) stock issued by such corporation) having voting power under ordinary circumstances to elect a majority of the board
of directors of such corporation is owned directly or indirectly by (i) the Company, (ii) the Company and one or more Subsidiaries or (iii) one or more Subsidiaries.

"TIA"
means the Trust Indenture Act of 1939 as in effect on the date of this Indenture, except as provided in Section 9.03.

"Trading
Day" means a day during which trading in securities generally occurs on the New York Stock Exchange or, if the applicable security is not listed on the New York Stock Exchange,
on the principal other national or regional securities exchange on which the applicable security is then listed or, if the applicable security is not listed on a national or regional securities
exchange, on the Nasdaq National Market or, if the applicable security is not quoted on the Nasdaq National Market, on the principal other market on which the applicable security is then traded.

"Trust
Officer" means any officer of the Trustee assigned by the Trustee to administer its corporate trust matters.

"Trustee"
means the party named as the "Trustee" in the first paragraph of this Indenture until a successor replaces it pursuant to the applicable provisions of this Indenture and,
thereafter, shall mean such successor. The foregoing sentence shall likewise apply to any subsequent, such successor or successors.

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Section 1.02.Other Definitions.

Term

Defined in
Section"Bankruptcy Law"

6.01"Company Notice"

3.08(b)"Conversion Agent"

2.03"Event of Default"

6.01"Fundamental Change Repurchase Date"

3.08(a)"Fundamental Change Redemption Notice"

3.08(c)"Fundamental Change Redemption Price"

3.08(a)"Legal Holiday"

11.08"Notice of Default"

6.01"Paying Agent"

2.03"Registrar"

2.03


Section 1.03.Incorporation by Reference of TIA.Whenever this Indenture refers to a provision of the
TIA, the provision is incorporated by reference in and made a part of this Indenture. The following TIA terms used in this Indenture have the following meanings:

"Commission"
means the SEC.

"Indenture
Securities" means the Securities.

"Indenture
Security Holder" means a Securityholder.

"Indenture
to be Qualified" means this Indenture.

"Indenture
Trustee" or "Institutional Trustee" means the Trustee.

"Obligor"
on the indenture securities means the Company.

All
other TIA terms used in this Indenture that are defined by the TIA, defined by TIA reference to another statute or defined by SEC rule have the meanings assigned to them by such
definitions.

Section 1.04.Rules of Construction.Unless the context otherwise requires:

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

(2)   an
accounting term not otherwise defined has the meaning assigned to it in accordance with generally accepted accounting principles as in effect from time to time;

(3)   "or"
is not exclusive;

(4)   "including"
means including, without limitation; and

(5)   words
in the singular include the plural, and words in the plural include the singular.

ARTICLE 2  THE SECURITIES

Section 2.01.Form and Dating.The Securities and the Trustee's certificate of authentication shall be
substantially in the form of Exhibit A, which is a part of this Indenture. The Securities may have notations, legends or endorsements required by law, stock exchange rule or usage (provided
that any such notation, legend or endorsement required by usage is in a form acceptable to the Company). The Company shall provide any such notations, legends or endorsements to the Trustee in
writing. Each Security shall be dated the date of its authentication.

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Section 2.02.Execution and Authentication.The Securities shall be executed on behalf of the Company by
its Chairman of the Board, one of its Vice Chairman, its President, one of its Senior Vice Presidents or one of its Vice Presidents, under its corporate seal reproduced thereon and attested by its
Secretary or one of its Assistant Secretaries. The signature of any of these officers on the Securities may be manual or facsimile.

Securities
bearing the manual or facsimile signatures of individuals who were at any time the proper Officers of the Company shall bind the Company, notwithstanding that such individuals
or any of them have ceased to hold such offices prior to the authentication and delivery of such Securities or did not hold such offices at the date of authentication of such Securities.

No
Security shall be entitled to any benefit under this Indenture or be valid or obligatory for any purpose unless there appears on such Security a certificate of authentication
substantially in the form provided for herein duly executed by the Trustee by manual signature of an authorized officer, and such certificate upon any Security shall be conclusive evidence, and the
only evidence, that such Security has been duly authenticated and delivered hereunder.

The
Trustee shall authenticate and deliver Securities for original issue in an aggregate principal amount of up to $234,500,000 upon a Company Order without any further action by the
Company. The aggregate principal amount of Securities outstanding at any time may not exceed the amount set forth in the foregoing sentence, subject to the proviso set forth therein, except as
provided in Section 2.07.

Section 2.03.Registrar, Paying Agent and Conversion Agent.The Company shall maintain an office or
agency where Securities may be presented for registration of transfer or for exchange ("Registrar"), an office or agency where Securities may be presented for purchase or payment ("Paying Agent") and
an office or agency where Securities may be presented for conversion ("Conversion Agent"). The Registrar shall keep a register (the "Security Register") of the Securities and of their transfer and
exchange. The Company may have one or more co-registrars, one or more additional paying agents and one or more additional conversion agents. The term Paying Agent includes any additional
paying agent. The term Conversion Agent includes any additional conversion agent.

The
Company shall enter into an appropriate agency agreement with any Registrar, Paying Agent, Conversion Agent or co-registrar (if not the Trustee). The agreement shall
implement the provisions of this Indenture that relate to such agent. The Company shall notify the Trustee of the name and address of any such agent. If the Company fails to maintain a Registrar,
Paying Agent or Conversion Agent, the Trustee shall act as such and shall be entitled to appropriate compensation therefor pursuant to Section 7.07. The Company or any Subsidiary or an
Affiliate of either of them may act as Paying Agent, Registrar, Conversion Agent or co-registrar.

The
Company initially appoints the Trustee as Registrar, Conversion Agent and Paying Agent in connection with the Securities.

Section 2.04.Paying Agent to Hold Money and Securities in Trust.Except as otherwise provided herein,
prior to or on each due date of payments in respect of any Security, the Company shall deposit with the Paying Agent a sum of money or securities sufficient to make such payments when so becoming due.
The Company shall require each Paying Agent (other than the Trustee) to agree in writing that the Paying Agent shall hold in trust for the benefit of Securityholders or the Trustee all money and
securities held by the Paying Agent for the making of payments in respect of the Securities and shall notify the Trustee of any default by the Company in making any such payment. At any time during
the continuance of any such default, the Paying Agent shall, upon the written request of the Trustee, forthwith pay to the Trustee all money and securities so held in trust. If the Company, a
Subsidiary or an Affiliate of either of them acts as Paying Agent, it shall segregate the money and securities held by it as Paying Agent and hold it as a separate trust fund. The Company at any time
may require a Paying Agent to pay all money and securities held by it to the Trustee and to account for

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any
funds and securities disbursed by it. Upon doing so, the Paying Agent shall have no further liability for the money or securities.

Section 2.05.Securityholder Lists.The Trustee shall preserve in as current a form as is reasonably
practicable the most recent list available to it of the names and addresses of Securityholders. If the Trustee is not the Registrar, the Company shall cause to be furnished to the Trustee at least
semiannually on February 15 and August 15 a listing of Holders dated within 15 days of the date on which the list is furnished and at such other times as the Trustee may request
in writing a list in such form and as of such date as the Trustee may reasonably require of the names and addresses of Securityholders.

Section 2.06.Exchange and Registration of Transfer of Securities; Depositary.Upon surrender for
registration of transfer of any Security at any office or agency of the Company designated as Registrar or co-registrar pursuant to Section 2.03 and satisfaction of the requirements
for such transfer set forth in this Section 2.06, the Company shall execute, and the Trustee shall authenticate and deliver, in the name of the designated transferee or transferees, one or more
new Securities of any authorized denominations and of a like aggregate principal amount.

Securities
may be exchanged for a like aggregate principal amount of Securities of other authorized denominations. Securities to be exchanged shall be surrendered at any office or agency
to be maintained by the Company designated as Registrar or co-registrar pursuant to Section 2.03 and the Company shall execute and register and the Trustee shall authenticate and
deliver in exchange therefor the Security or Securities which the Securityholder making the exchange shall be entitled to receive, bearing registration numbers not contemporaneously outstanding.

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

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

None
of the Company, the Trustee, the Registrar or any co-registrar shall be required to exchange or register a transfer of (a) any Securities for a period of
15 days next preceding any selection of Securities to be redeemed or (b) any Securities or portions thereof selected or called for redemption or (c) any Securities or portion
thereof surrendered for conversion or (d) any Securities or portion thereof surrendered for redemption (and not withdrawn) pursuant to Section 3.08.

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

The
provisions of Clauses (1), (2), (3), (4) and (5) below shall apply only to Global Securities:



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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
Securities in global form. Initially, the Global Security shall be issued to the Depositary, registered in the name of Cede & Co., as the nominee of the Depositary, and deposited with the
Trustee as custodian for Cede & Co.

If
at any time the Depositary for the Global Security notifies the Company that it is unwilling or unable to continue as Depositary for such Global Security, the Company may appoint a
successor Depositary with respect to such Security. If a successor Depositary for the Global Security is not appointed by the Company within 90 days after the Company receives such notice, the
Company will execute, and the Trustee, upon receipt of a Company Order for authentication and delivery of Securities, will authenticate and deliver, Securities in definitive form, in an aggregate
principal amount equal to the principal amount of the Global Security, in exchange for the such Security in the global form.

Section 2.07.Replacement Securities.If (a) any mutilated Security is surrendered to the Trustee,
or (b) the Company and the Trustee receive evidence to their satisfaction of the destruction, loss or theft of any Security, and there is delivered to the Company and the Trustee such security
or indemnity as may be required by them to save each of them harmless, then, in the absence of notice to the Company or the Trustee that such Security has been acquired by a bona fide purchaser, the
Company shall execute and upon its written request the Trustee shall authenticate and deliver, in exchange for any such mutilated Security or in lieu of any such destroyed, lost or stolen Security, a
new Security of like tenor and principal amount, bearing a number not contemporaneously outstanding.

In
case any such mutilated, destroyed, lost or stolen Security has become or is about to become due and payable, or is about to be redeemed by the Company pursuant to Article 3
hereof, the Company in its discretion may, instead of issuing a new Security, pay or redeem such Security, as the case may be.

Upon
the issuance of any new Securities under this Section, the Company may require the payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in

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relation
thereto and any other expenses (including the fees and expenses of the Trustee) connected therewith.

Every
new Security issued pursuant to this Section in lieu of any mutilated, destroyed, lost or stolen Security shall constitute an original additional contractual obligation of the
Company, whether or not the destroyed, lost or stolen Security shall be at any time enforceable by anyone, and shall be entitled to all benefits of this Indenture equally and proportionately with any
and all other Securities duly issued hereunder.

The
provisions of this Section are exclusive and shall preclude (to the extent lawful) all other rights and remedies with respect to the replacement or payment of mutilated, destroyed,
lost or stolen Securities.

Section 2.08.Outstanding Securities; Determinations of Holders' Action.Securities outstanding at any
time are all the Securities authenticated by the Trustee except for those canceled by it, those delivered to it for cancellation and those described in this Section 2.08 as not outstanding. A
Security does not cease to be outstanding because the Company or an Affiliate thereof holds the Security; provided, however, that in determining whether the Holders of the requisite principal amount
of Securities have given or concurred in any request, demand, authorization, direction, notice,. consent or waiver hereunder, Securities owned by the Company or any other obligor upon the Securities
or any Affiliate of the Company or such other obligor shall be disregarded and deemed not to be outstanding, except that, in determining whether the Trustee shall be protected in relying upon any such
request, demand, authorization, direction, notice, consent or waiver, only Securities which the Trustee knows to be so owned shall be so disregarded. Subject to the foregoing, only Securities
outstanding at the time of such determination shall be considered in any such determination (including, without limitation, determinations pursuant to Articles 6 and 9).

If
a Security is replaced pursuant to Section 2.07, it ceases to be outstanding unless the Trustee receives proof satisfactory to it that the replaced Security is held by a bona
fide purchaser.

If
the Paying Agent holds, in accordance with this Indenture, on a Redemption Date, on a Fundamental Change Repurchase Date or on Stated Maturity, money or securities, if permitted
hereunder, sufficient to pay Securities payable on that date, then on and after that date such Securities shall cease to be outstanding and interest on such Securities shall cease to accrue; provided,
that if such Securities are to be redeemed, notice of such redemption has been duly given pursuant to this Indenture or provision therefor satisfactory to the Trustee has been made.

If
a Security is converted in accordance with Article 10, then from and after such conversion such Security shall cease to be outstanding and interest shall cease to accrue on
such Security.

Section 2.09.Temporary Securities.Pending the preparation of definitive Securities, the Company may
execute, and upon Company Order the Trustee shall authenticate and deliver, temporary Securities which are printed, lithographed, typewritten, mimeographed or otherwise produced, in any authorized
denomination, substantially of the tenor of the definitive Securities in lieu of which they are issued and with such appropriate insertions, omissions, substitutions and other variations as the
officers executing such Securities may determine, as conclusively evidenced by their execution of such Securities.

If
temporary Securities are issued, the Company will cause definitive Securities to be prepared without unreasonable delay. After the preparation of definitive Securities, the temporary
Securities shall be exchangeable for definitive Securities upon surrender of the temporary Securities at the office or agency of the Company designated for such purpose pursuant to
Section 2.03, without charge to the Holder. Upon surrender for cancellation of any one or more temporary Securities the Company shall execute and the Trustee shall authenticate and deliver in
exchange therefor a like principal amount of definitive Securities of authorized denominations. Until so exchanged the temporary Securities shall in all respects be entitled to the same benefits under
this Indenture as definitive Securities.

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Section 2.10.Cancellation.All Securities surrendered for payment, conversion, redemption or,
registration of transfer or exchange shall, if surrendered to any Person other than the Trustee, be delivered to the Trustee and shall be promptly canceled by it. The Company may at any time deliver
to the Trustee for cancellation any Securities previously authenticated and delivered hereunder which the Company may have acquired in any manner whatsoever, and all Securities so delivered shall be
promptly canceled by the Trustee. The Company may not issue new Securities to replace Securities it has paid or delivered to the Trustee for cancellation or that any Holder has converted pursuant to
Article 10. No Securities shall be authenticated in lieu of or in exchange for any Securities canceled as provided in this Section, except as expressly permitted by this Indenture. All canceled
Securities held by the Trustee shall be destroyed by the Trustee and evidence of their destruction delivered to the Company unless the Company directs by Company Order that the Trustee deliver
canceled Securities to the Company.

Section 2.11.Persons Deemed Owners.Prior to due presentment of a Security for registration of transfer,
the Company, the Trustee and any agent of the Company or the Trustee may treat the Person in whose name such Security is registered as the owner of such Security for the purpose of receiving payment
of principal amount, premium, if any, interest, Redemption Price and Fundamental Change Redemption Price in respect thereof, for the purpose of conversion and for all other purposes whatsoever,
whether or not such Security be overdue, and none of the Company, the Trustee or any agent of the Company or the Trustee shall be affected by notice to the contrary.

Section 2.12.Payment of Interest; Interest Rights Preserved.Interest on any Security which is payable,
and is punctually paid or duly provided for, on any Interest Payment Date shall be paid to the person in whose name that Security (or one or more Predecessor Securities) is registered at the close of
business on the Regular Record Date for such interest.

Any
interest on any Security which is payable, but is not punctually paid or dully provided for, on any Interest Payment Date (herein called "Defaulted Interest") shall forthwith cease
to be payable to the Holder on the relevant Regular Record Date by virtue of having been such Holder, and such Defaulted Interest may be paid by the Company, at its election in each case, as provided
in Clause (a) or (b) below:



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Subject
to the foregoing provisions of this Section, each Security delivered under this Indenture upon registration of transfer of or in exchange for or in lieu of any other Security
shall carry the rights to interest accrued and unpaid, and to accrue, which were carried by such other Security.

In
the case of any Security which is converted after any Regular Record Date on or prior to the close of business on the next succeeding Interest Payment Date (other than any Security
whose Maturity is prior to such Interest Payment Date), interest whose Stated Maturity is on such Interest Payment Date shall be payable on such Interest Payment Date notwithstanding such conversion,
and such interest (whether or not punctually paid or dully provided for) shall be paid to the Person whose name that Security (or one or more Predecessor Securities) is registered at the close of
business on such Regular Record Date. Except as otherwise expressly provided in the immediately preceding sentence, in the case of any Security which is converted, interest whose Stated Maturity is
after the date of conversion of such Security shall not be payable.

Section 2.13.Computation of Interest.Interest on the Securities shall be computed on the basis of a
360-day year of twelve 30-day months.

Section 2.14.Preservation of Information; Communications to Holders.

(a)   The
Trustee shall preserve, in as current a form as is reasonably practicable, the names and addresses of Holders contained in the most recent list furnished to the
Trustee as provided in Section 2.05 and the names and addresses of Holders received by the Trustee in its capacity as Security Registrar. The Trustee may destroy any list furnished to it as
provided in Section 2.05 upon receipt of a new list so furnished.

(b)   The
rights of Holders to communicate with other Holders with respect to their rights under this Indenture or under the Securities, and the corresponding right and duties
of the Trustee, shall be as provided in the TIA.

(c)   Every
Holder of Securities, 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 the disclosure of information as to names and addresses of the Holders made pursuant to the TIA.

ARTICLE 3  REDEMPTION

Section 3.01.Right to Redeem; Notices to Trustee.The Company, at its option, may redeem the Securities
in accordance with the provisions of paragraph 5 of the Securities. If the Company elects to redeem Securities pursuant to paragraph 5 of the Securities, it shall notify the Trustee in
writing of the Redemption Date, the principal amount of Securities to be redeemed, the Redemption Price, and the amount of accrued interest to, but excluding, the Redemption Date.

The
Company shall give the notice to the Trustee provided for in this Section 3.01 (i) in the case of any redemption of fewer than all of the Securities, at least
45 days before the Redemption Date and (ii) in the case of a redemption of all of the Securities, no later than the Company is required to give notice to the Holders pursuant to
Section 3.03, in each case unless a shorter notice shall be satisfactory to the Trustee.

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Section 3.02.Selection of Securities to be Redeemed.If less than all the Securities are to be redeemed,
the Trustee shall select the Securities to be redeemed pro rata or by lot or by a method the Trustee considers fair and appropriate (as long as such method is not prohibited by the rules of any stock
exchange or automated quotation system on which the Securities are then listed). The Trustee shall make the selection at least 35 days, but not more than 60 days, before the Redemption
Date from outstanding Securities not previously called for redemption. The Trustee may select for redemption portions of the principal amount of Securities that have denominations larger than $1,000.
Securities and portions of them the Trustee selects shall be in principal amounts of $1,000 or a multiple of $1,000. Provisions of this Indenture that apply to Securities called for redemption also
apply to portions of Securities called for redemption. The Trustee shall notify the Company promptly of the Securities or portions of Securities to be redeemed.

If
any Security selected for partial redemption is converted in part before termination of the conversion right with respect to the portion of the Security so selected, the converted
portion of such Security shall be deemed (so far as may be) to be the portion selected for redemption. Securities which have been converted during a selection of Securities to be redeemed may be
treated by the Trustee as outstanding for the purpose of such selection.

Section 3.03.Notice of Redemption.At least 30 days but not more than 60 days before a
Redemption Date, the Company shall mail a notice of redemption by first-class mail, postage prepaid, to each Holder of Securities to be redeemed.

The
notice shall identify the Securities to be redeemed and shall state:



At
the Company's request, the Trustee shall give the notice of redemption in the Company's name and at the Company's expense.

Section 3.04.Effect of Notice of Redemption.Once notice of redemption is given, Securities called for
redemption become due and payable on the Redemption Date and at the Redemption Price, together with accrued interest to, but excluding, the Redemption Date, stated in the notice except for Securities
which are converted in accordance with the terms of this Indenture.

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Upon
the later of the Redemption Date or the date such Securities are surrendered to the Paying Agent, such Securities shall be paid at the Redemption Price, together with accrued
interest to, but excluding, the Redemption Date, stated in the notice.

Section 3.05.Deposit of Redemption Price.Prior to or on the Redemption Date, the Company shall deposit
with the Paying Agent (or if the Company or a Subsidiary or an Affiliate of either of them is the Paying Agent, shall segregate and hold in trust) money sufficient to pay the Redemption Price and
accrued interest to, but excluding, the Redemption Date of all Securities to be redeemed on that date other than Securities or portions of Securities called for redemption which prior thereto have
been delivered by the Company to the Trustee for cancellation or have been converted; provided 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 Redemption Date. The Paying Agent shall as promptly as practicable return to the Company any money, with interest, if any, thereon
(subject to the provisions of Section 7.01(f)), not required for that purpose because of conversion of Securities. If such money is then held by the Company in trust and is not required for
such purpose it shall be discharged from such trust.

Section 3.06.Securities Redeemed in Part.Upon surrender of a Security that is redeemed in part, the
Company shall execute and the Trustee shall authenticate and deliver to the Holder a new Security in an authorized denomination equal in principal amount to the unredeemed portion of the Security
surrendered.

Section 3.07.Conversion Arrangement on Call for Redemption.In connection with any redemption of
Securities, the Company may arrange for the purchase and conversion of any Securities called for redemption by an agreement with one or more investment bankers or other purchasers to purchase such
Securities by paying to the Paying Agent in trust for the Securityholders, on or before the close of business on the Redemption Date, an amount that, together with any amounts deposited with the
Paying Agent by the Company for the redemption of the Securities, is not less than the Redemption Price, together with interest, if any, accrued to the Redemption Date, of such Securities.
Notwithstanding anything to the contrary contained in this Article 3, the obligation of the Company to pay the Redemption Price of such Securities, including all accrued interest, 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, any Securities 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 10) surrendered by such purchasers for conversion, all immediately prior to the close of business on the
Redemption Date, subject to payment of the above amount as aforesaid. The Paying Agent shall hold and pay to the Holders whose Securities are selected for redemption any such amount paid to it in the
same manner as it would moneys deposited with it by the Company for the redemption of Securities. Without the Paying Agent's prior written consent, no arrangement between the Company and such
purchasers for the purchase and conversion of any Securities shall increase or otherwise affect any of the powers, duties, responsibilities or obligations of the Paying Agent as set forth in this
Indenture, and the Company agrees to indemnify the Paying Agent from, and hold it harmless against, any loss, liability or expense arising out of or in connection with any such arrangement for the
purchase and conversion of any Securities between the Company and such purchasers, including the costs and expenses incurred by the Paying Agent in the defense of any claim or liability arising out of
or in connection with the exercise or performance of any of its powers, duties, responsibilities or obligations under this Indenture.

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Section 3.08.Redemption at Option of the Holder upon a Fundamental Change.(a) If a Fundamental
Change shall occur at any time prior to September 1, 2004, each Holder of Securities shall have the right, at such Holder's option, to require the Company to redeem such Holder's Securities on
the date (the "Fundamental Change Repurchase Date") (or if such date is not a Business Day, the next succeeding Business Day) that is 45 days after the date of the Company's notice of such
Fundamental Change. The Securities will be redeemable in part in multiples of $1,000 of principal amount. Such repayment shall be made at the following prices (the "Fundamental Change Redemption
Price") (expressed as percentages of the principal amount) in the event of a Fundamental Change Repurchase Date occurring during the 12-month period beginning September 1:

Year

Percentage

Year

Percentage1997

105.25%

2001

102.25%1998

104.50

2002

101.501999

103.75

2003

100.752000

103.00


and
100% at September 1, 2004; provided that if the Applicable Price with respect to the Fundamental Change is less than the Reference Market Price, the Company shall redeem such Securities at
a price equal to the foregoing redemption price multiplied by the fraction obtained by dividing the Applicable Price by the Reference Market Price. In each case, the Company shall also pay to such
Holders accrued interest to, but excluding, the Fundamental Change Repurchase Date on the redeemed
Securities; provided that if such Fundamental Change Repurchase Date is an Interest Payment Date, then the interest payable on such date shall be paid to the Holder of the Security on the next
preceding the Regular Record Date.

(b)   On
or before the tenth day after the occurrence of a Fundamental Change, the Company, or, at its written request (which must be received by the Trustee at least five
Business Days prior to the date the Trustee is requested to give notice as described below), 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 Fundamental Change a notice (the "Company Notice") of the occurrence of such Fundamental Change 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 Section 3.03. The Company shall also deliver a copy of the Company Notice to the Trustee at such
time as it is mailed to the Holders.

Each
Company Notice shall specify the circumstances constituting the Fundamental Change, the Fundamental Change Repurchase Date, the Fundamental Change Redemption Price at which the
Company shall be obligated to redeem the Securities, the amount of interest accrued on each Security to, but excluding, the Fundamental Change Repurchase Date, the latest time by which the Holder must
exercise the redemption right (the "Fundamental Change Expiration Time"), that the Holder shall have the right to withdraw any Notes prior to the Fundamental Change Expiration Time, a description of
the procedure which a Holder must follow to exercise such redemption right and to withdraw any surrendered Notes and the place or places where the Holder is to surrender such Holder's Securities.

No
failure of the Company to give the foregoing notices and no defect therein shall limit the Holders' redemption rights or affect the validity of the proceedings for the repurchase of
the Securities pursuant to this Section 3.08.

(c)   For
a Security to be so redeemed at the option of the Holder, the Paying Agent must receive such Security with the form entitled "Option to Elect Redemption Upon a
Fundamental Change" on the reverse thereof duly completed (a "Fundamental Change Redemption Notice"), together with such Security duly endorsed for transfer, on or before the 30th day after the date
of such Company Notice (or if such 30th day is not a Business Day, the immediately preceding Business Day). All questions as

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to
the validity, eligibility (including time of receipt) and acceptance of any Security for redemption shall be determined by the Company, whose determination shall be final and binding.

(d)   Upon
receipt by the Company of the Fundamental Change Redemption Notice specified in Section 3.08(c), the Holder of the Security in respect of which such
Fundamental Change Redemption Notice was given shall (unless such Fundamental Change Redemption Notice is withdrawn as specified in the following two paragraphs) thereafter be entitled to receive
solely the Fundamental Change Redemption Price, together with accrued interest to, but excluding, the Fundamental Change Repurchase Date, with respect to such Security. Such Fundamental Change
Redemption Price together with accrued interest to, but excluding, the Fundamental Change Repurchase Date, shall be paid to such Holder promptly following the Fundamental Change Repurchase Date.
Securities in respect of which a Fundamental Change Redemption Notice has been given by the Holder thereof may not be converted into shares of Common Stock on or after the date of the delivery of such
Fundamental Change Redemption Notice, unless such Fundamental Change Redemption Notice has first been validly withdrawn as specified in the following two paragraphs.

A
Fundamental Change Redemption Notice may be withdrawn by the Holder by means of a written notice of withdrawal delivered to the office of the Paying Agent at any time prior to the
close of business on the Fundamental Change Repurchase Date to which it relates specifying:



There
shall be no redemption pursuant to Section 3.08 if there has occurred prior to, on or after, as the case may be, the giving, by the Holders of such Securities, of the
required Fundamental Change Redemption Notice and is continuing an Event of Default (other than a default in the payment of the Fundamental Change Redemption Price, together with accrued interest to,
but excluding, the Fundamental Change Repurchase Date, with respect to such Securities).

(e)   On
or before the Fundamental Change Repurchase Date the Company shall deposit with the Trustee or with the Paying Agent (or, if the Company or a Subsidiary or an
Affiliate of either of them is acting as the Paying Agent, shall segregate and hold in trust as provided in Section 2.04) an amount of money and/or securities, if permitted hereunder,
sufficient to pay the aggregate Fundamental Change Redemption Price, together with accrued interest to, but excluding, the Fundamental Change Repurchase Date, of all the Securities or portions thereof
which are to be redeemed as of such Fundamental Change Repurchase Date; provided that if such payment is made on the Fundamental Change 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 Fundamental Change Repurchase Date.

(f)    Any
Security that is to be redeemed upon a Fundamental Change only in part shall be surrendered at the office of the Paying Agent (with, if the Company or the Trustee so
requires, due endorsement by, or a written instrument of transfer in form satisfactory to the Company and the Trustee duly executed by, the Holder thereof or such Holder's attorney duly authorized in
writing) and the Company shall execute and, upon the Company's written direction to the Trustee, the Trustee shall authenticate and deliver to the Holder of such Security, without service charge, a
new Security or Securities, of any authorized denomination as requested by such Holder in aggregate principal amount equal to, and in exchange for, the portion of the principal amount of the Security
so surrendered which is not redeemed.

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(g)   In
connection with any offer to redeem Securities under Section 3.08 hereof, the Company shall (i) comply with Rule 13e-4 (which term,
as used herein, includes any successor provision thereto) under the Exchange Act, if applicable, (ii) file, if applicable, the related Schedule 13E-4 (or any successor
schedule, form or report) under the Exchange Act and (iii) otherwise comply with all Federal and state securities laws so as to permit the rights and obligations under Section 3.08 to be
exercised in the time and in the manner specified in Section 3.08.

(h)   The
Trustee and the Paying Agent shall return to the Company any cash that remains unclaimed as provided in paragraph 11 of the Securities, together with interest
or dividends, if any (subject to the provisions of Section 7.01(f)), thereon, held by them for the payment of a Fundamental Change Redemption Price, together with accrued interest to, but
excluding, the Fundamental Change Repurchase Date; provided, however, that to the extent that the aggregate amount of cash deposited by the Company pursuant to Section 3.08 exceeds the
aggregate Fundamental Change Redemption Price, together with accrued interest to, but excluding, the Fundamental Change Repurchase Date, of the Securities or portions thereof which the Company is
obligated to purchase as of the Fundamental Change Repurchase Date then promptly after the Business Day following the Fundamental Change Repurchase Date the Trustee and the Paying Agent shall return
any such excess to the Company together with interest or dividends, if any, thereon.

ARTICLE 4  COVENANTS

Section 4.01.Payment of Securities.The Company shall promptly make all payments in respect of the
Securities on the dates and in the manner provided in the Securities or pursuant to this Indenture. The principal amount, premium, if any, accrued interest, Redemption Price and Fundamental Change
Redemption Price shall be considered paid on the applicable date due if on such date the Trustee or
the Paying Agent holds on or before 10:00 a.m. New York City time on such date, in accordance with this Indenture, money or securities, if permitted hereunder, sufficient to pay all such amount
then due.

The
Company shall pay interest at the rate set forth in paragraph I of the Securities and it shall pay interest on overdue interest at the same rate compounded semiannually (to
the extent that the payment of such interest shall be legally enforceable), which interest on overdue interest shall accrue from the date such amounts became overdue.

Section 4.02.SEC Reports.The Company shall file with the Trustee, within 15 days after it files
such annual and quarterly reports, information, documents and other reports with the SEC, copies of its annual report and of the information, documents and other reports (or copies of such portions of
any of the foregoing as the SEC may by rules and regulations prescribe) which the Company is required to file with the SEC pursuant to Section 13 or 15(d) of the Exchange Act.

Section 4.03.Compliance Certificate.The Company shall deliver to the Trustee within 120 days
after the end of each fiscal year of the Company (beginning with the fiscal year ending on June 30, 1998) an Officers' Certificate stating whether or not the signers know of any Default that
occurred during such period. If they do, such Officers' Certificate shall describe the Default and its status.

Section 4.04.Further Instruments and Acts.Upon request of the Trustee, the Company will execute and
deliver such further instruments and do such further acts as may be reasonably necessary or proper to carry out more effectively the purposes of this Indenture.

Section 4.05.Maintenance of Office or Agency.The Company will maintain in the Borough of Manhattan, The
City of New York, an office or agency where Securities may be presented or surrendered for payment, where Securities may be surrendered for registration of transfer, exchange, redemption or conversion
and where notices and demands to or upon the Company in respect of the

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Securities
and this Indenture may be served. The office of State Street Bank and Trust Company, N.A., an Affiliate of the Trustee, at 61 Broadway, Concourse Level, Corporate Trust Window, New York,
New York 10006, shall be such office or agency for all of the aforesaid purposes unless the Company shall maintain some other office or agency for such purposes and shall give prompt written notice to
the Trustee of the location, and any change in the location, of such other office or agency. If at any time the Company shall fail to maintain any such required office or agency or shall fail to
furnish the Trustee with the address thereof, such presentations, surrenders, notices and demands may be made or served at the address of the Trustee set forth in Section 12.02.

The
Company may also from time to time designate one or more other offices or agencies where the Securities may be presented or surrendered for any or all such purposes and may from time
to time rescind such designations; provided, however, that no such designation or rescission shall in any manner relieve the Company of its obligation to maintain an office or agency in the Borough of
Manhattan, The City of New York, for such purposes.

ARTICLE 5  SUCCESSOR CORPORATION

Section 5.01.When Company May Merge or Transfer Assets.The Company shall not consolidate with or merge
with or into any other Person (other than in a merger or consolidation in which the Company is the surviving Person) or convey, transfer or lease its properties and assets substantially as an entirety
to any Person, unless:



The
successor Person formed by such consolidation or into which the Company is merged or the successor Person to which such conveyance, transfer or lease is made shall succeed to, and be
substituted for, and may exercise every right and power of, the Company under this Indenture with the same effect as if such successor had been named as the Company herein; and thereafter, except in
the case of (i) a lease of its properties and assets substantially as an entirety and (ii) obligations the Company may have under a supplemental indenture pursuant to
Section 10.14, the Company shall be discharged from all obligations and covenants under this Indenture and the Securities.

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ARTICLE 6  DEFAULTS AND REMEDIES

Section 6.01.Events of Default.An "Event of Default" occurs if:



"Bankruptcy
Law" means Title 11, United States Code, or any similar Federal or state law for the relief of debtors.

A
Default under clause (3) above is not an Event of Default until the Trustee notifies the Company, or the Holders of at least 25% in aggregate principal amount of the Securities
at the time outstanding notify the Company and the Trustee, of the Default and the Company does not cure such Default (and such Default is not waived) within the time specified in clause (3)
above after actual receipt of such notice (a "Notice of Default"). Any such notice must specify the Default, demand that it be remedied and state that such notice is a Notice of Default.

Section 6.02.Acceleration.If an Event of Default (other than an Event of Default specified in
Section 6.01(4) or (5)) occurs and is continuing, the Trustee by notice to the Company, or the Holders of at least 25% in aggregate principal amount of the Securities at the time outstanding by
notice to the Company and the Trustee, may declare the principal amount and premium, if any, on all the Securities and the interest accrued thereon to be immediately due and payable. Upon such a
declaration, such principal amount, premium, if any, and interest accrued thereon shall be due and payable immediately. If an Event of Default specified in Section 6.01(4) or (5) occurs
and is continuing, the principal amount and premium, if any, on all the Securities and the interest accrued thereon shall become and be immediately due and payable without any declaration or other act
on the part of the Trustee or any Securityholders. The Holders of a majority in aggregate principal amount of the Securities at the time outstanding, by notice to the Trustee (and without notice to
any other Securityholder) may rescind an acceleration and its consequences if the rescission would not conflict with any judgment or decree and

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if
all existing Events of Default have been cured or waived except nonpayment of the principal amount, premium, if any, and interest accrued thereon that has become due solely as a result of
acceleration and if all amounts due to the Trustee under Section 7.07 have been paid. No such rescission shall affect any subsequent Default or impair any right consequent thereto.

Section 6.03.Other Remedies.If an Event of Default occurs and is continuing, the Trustee may pursue any
available remedy to collect the payment of the principal amount and premium, if any, on the Securities and interest accrued thereon or to' enforce the performance of any provision of the Securities or
this Indenture.

The
Trustee may maintain a proceeding even if the Trustee does not possess any of the Securities or does not produce any of the Securities in the proceeding. A delay or omission by the
Trustee or any Securityholder in exercising any right or remedy accruing upon an Event of Default shall not impair the right or remedy or constitute a waiver of, or acquiescence in, the Event of
Default. No remedy is exclusive of any other remedy. All available remedies are cumulative.

Section 6.04.Waiver of Past Defaults.The Holders of a majority in aggregate principal amount of the
Securities at the time outstanding, by notice to the Trustee (and without notice to any other Securityholder), may waive an existing Default and its consequences except (1) an Event of Default
described in Section 6.01(1) or 6.01(2), (2) a Default in respect of a provision that under Section 9.02 cannot be amended without the consent of each Securityholder affected or
(3) a Default that constitutes a failure to convert any Security in accordance with the terms of Article 10. When a Default is waived, it is deemed cured, but no such waiver shall extend
to any subsequent or other Default or impair any consequent right.

Section 6.05.Control by Majority.The Holders of a majority in aggregate principal amount of the
Securities at the time outstanding may direct the time, method and place of conducting any proceeding for any remedy available to the Trustee or of exercising any trust or power conferred on the
Trustee. However, the Trustee may refuse to follow any direction that conflicts with law or this Indenture or that the Trustee determines in good faith is unduly prejudicial to the rights of other
Securityholders or would involve the Trustee in personal liability unless the Trustee is offered indemnity satisfactory to it.

Section 6.06.Limitation on Suits.A Securityholder may not pursue any remedy with respect to this
Indenture or the Securities unless:



A
Securityholder may not use this Indenture to prejudice the rights of any other Securityholder or to obtain a preference or priority over any other Securityholder.

Section 6.07.Rights of Holders to Receive Payment.Notwithstanding any other provision of this
Indenture, the right of any Holder to receive payment of the principal amount, premium, if any,

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accrued
interest, Redemption Price or Fundamental Change Redemption Price in respect of the Securities held by such Holder, on or after the respective due dates expressed in the Securities or any
Redemption Date or Fundamental Change Repurchase Date, as the case may be, and to convert the Securities in accordance with Article 10, or to bring suit for the enforcement of any such payment
on or after such respective dates or the right to convert, shall not be impaired or affected adversely without the consent of each such Holder.

Section 6.08.Collection Suit by Trustee.If an Event of Default described in Section 6.01(1) or
6.01(2) occurs and is continuing, the Trustee may recover judgment in its own name and as trustee of an express trust against the Company for the whole amount owing with respect to the Securities and
the amounts provided for in Section 7.07.

Section 6.09.Trustee May File Proofs of Claim.In case of the pendency of any receivership, insolvency,
liquidation, bankruptcy, reorganization, arrangement, adjustment, composition or other judicial proceeding relative to the Company or any other obligor upon the Securities or the property of the
Company or of such other obligor or their creditors, the Trustee (irrespective of whether the principal amount, premium, if any, accrued interest, Redemption Price or Fundamental Change Redemption
Price in respect of the Securities 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 on the Company
for the payment of any such amount) shall be entitled and empowered, by intervention in such proceeding or otherwise,



and
any custodian, receiver, assignee, trustee, liquidator, sequestrator or similar official in any such judicial proceeding is hereby authorized by each Holder 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 Holders, to pay the Trustee any amount due it for the reasonable compensation, expenses, disbursements
and advances of the Trustee, its agents and counsel, and any other amounts due the Trustee under Section 7.07.

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

Section 6.10.Priorities.If the Trustee collects any money pursuant to this Article 6, it shall
pay out the money in the following order:



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The
Trustee may fix a record date and payment date for any payment to Securityholders pursuant to this Section 6.10. At least 15 days before such record date, the Company
shall mail to each Securityholder and the Trustee a notice that states the record date, the payment date and amount to be paid.

Section 6.11.Undertaking for Costs.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, a court in
its discretion may require the filing by any party litigant (other than the Trustee) in the suit of an undertaking to pay the costs of the suit, and the court in its discretion may assess reasonable
costs, including reasonable attorneys' fees, against any party litigant in the suit, having due regard to the merits and good faith of the claims or defenses made by the party litigant. This
Section 6.11 does not apply to a suit by the Trustee, a suit by a Holder pursuant to Section 6.07 or a suit by Holders of more than 10% in aggregate principal amount of the Securities at
the time outstanding.

Section 6.12.Waiver of Stay, Extension or Usury Laws.The Company covenants (to the extent that it may
lawfully do so) that it will not at any time insist upon, or plead, or in any manner whatsoever claim or take the benefit or advantage of, any stay or extension law or any usury or other law wherever
enacted, now or at any time hereafter in force, which would prohibit or forgive the Company from paying all or any portion of the principal amount, premium, if any, accrued interest, Redemption Price
or Fundamental Change Redemption Price in respect of Securities as contemplated herein, or which may affect the covenants or the performance of this Indenture; and the Company (to the extent that it
may lawfully do so) hereby expressly waives all benefit or advantage of any such laws and covenants that it will not 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.

ARTICLE 7  TRUSTEE

Section 7.01.Duties of Trustee.(a) If an Event of Default has occurred and is continuing, the
Trustee shall exercise the rights and powers vested in it by this Indenture and use the same degree of care and skill in its exercise as a prudent man would exercise or use under the circumstances in
the conduct of his own affairs.

(b)   Except
during the continuance of an Event of Default:



(c)   The
Trustee may not be relieved from liability for its own negligent action, its own negligent failure to act or its own willful misconduct, except that:



21

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(d)   Every
provision of this Indenture that in any way relates to the Trustee is subject to paragraphs (a), (b), (c) and (e) of this Section 7.01.

(e)   The
Trustee may refuse to perform any duty or exercise any right or power or extend or risk its own funds or otherwise incur any financial liability unless it receives
indemnity satisfactory to it against any loss, liability or expense.

(f)    Money
held by the Trustee in trust hereunder need not be segregated from other funds except to the extent required by law.

Section 7.02.Rights of Trustee.(a) The Trustee may rely on any document believed by it to be
genuine and to have been signed or presented by the proper person. The Trustee need not investigate any fact or matter stated in the document.

(b)   Before
the Trustee acts or refrains from acting, it may require a Company Order, an Officers' Certificate or an Opinion of Counsel. The Trustee shall not be liable for
any action it takes or omits to take in good faith in reliance on such Company Order, Officers' Certificate or Opinion of Counsel.

(c)   The
Trustee may act through agents and shall not be responsible for the misconduct or negligence of any agent appointed with due care.

(d)   Subject
to the provisions of Section 7.01(c), the Trustee shall not be liable for any action it takes or omits to take in good faith which it believes to be
authorized or within its rights or powers.

Section 7.03.Individual Rights of Trustee.The Trustee in its individual or any other capacity may
become the owner or pledgee of Securities and may otherwise deal with the Company or its Affiliates with the same rights it would have if it were not Trustee. Any Paying Agent, Registrar, Conversion
Agent or co-registrar may do the same with the like rights. However, the Trustee must comply with Section 7.10.

Section 7.04.Trustee's Disclaimer.The Trustee makes no representation as to the validity or adequacy of
this Indenture or the Securities, it shall not be accountable for the Company's use of the proceeds from the Securities, it shall not be responsible for any statement in the Prospectus for the
Securities or in the Indenture or the Securities (other than its certificate of authentication), the acts of an prior Trustee hereunder, or the determination as to which beneficial owners are entitled
to receive any notices hereunder.

Section 7.05.Notice of Defaults.If a Default occurs and is continuing and if it is known to the
Trustee, the Trustee shall give to each Securityholder notice of the Default within 90 days after it occurs. Except in the case of a Default described in Section 6.01(1) or 6.01(2), the
Trustee may withhold the notice if and so long as a committee of its Trust Officers in good faith determines that withholding the notice is in the interests of Securityholders. The Trustee shall not
give notice of a Default pursuant to Section 6.01(3) until at least sixty (60) days have passed since its occurrence.

Section 7.06.Disqualification; Conflicting Interests.If the Trustee has or shall acquire any
conflicting interest within the meaning of the TIA, it shall either eliminate such conflicting interest or resign, to the extent and in the manner provided by, and subject to the provisions of the TIA
and this Indenture.

Section 7.07.Compensation and Indemnity.The Company agrees:



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To
secure the Company's payment obligations in this Section 7.07, the Trustee shall have a lien prior to the Securities on all money or property held or collected by the Trustee,
except that held in trust to pay the principal amount, premium, if any, accrued interest, Redemption Price or Fundamental Change Redemption Price, as the case may be, on particular Securities.

The
Company's payment obligations pursuant to this Section 7.07 shall survive the discharge of this Indenture. When the Trustee incurs expenses after the occurrence of a Default
specified in Section 6.01(4) or (5), the expenses are intended to constitute expenses of administration under any Bankruptcy Law.

Section 7.08.Replacement of Trustee.The Trustee may resign by so notifying the Company; provided,
however, no such resignation shall be effective until a successor Trustee has accepted its appointment pursuant to this Section 7.08. The Holders of a majority in aggregate principal amount of
the Securities at the time outstanding may remove the Trustee by so notifying the Trustee and may appoint a successor Trustee. The Company shall remove the Trustee if:



If
the Trustee resigns or is removed or if a vacancy exists in the office of Trustee for any reason, the Company shall promptly appoint, by resolution of its Board of Directors, a
successor Trustee.

A
successor Trustee shall deliver a written acceptance of its appointment to the retiring Trustee and to the Company. Thereupon the resignation or removal of the retiring Trustee shall
become effective, and the successor Trustee shall have all the rights, powers and duties of the Trustee under this Indenture. The successor Trustee shall mail a notice of its succession to
Securityholders. The retiring Trustee shall promptly transfer all property held by it as Trustee to the successor Trustee, subject to the lien provided for in Section 7.07.

If
a successor Trustee does not take office within 30 days after the retiring Trustee resigns or is removed, the retiring Trustee, the Company or the Holders of a majority in
aggregate principal amount of the Securities at the time outstanding may petition any court of competent jurisdiction for the appointment of a successor Trustee.

If
the Trustee fails to comply with Section 7.10, any Securityholder may petition any court of competent jurisdiction for the removal of the Trustee and the appointment of a
successor Trustee.

Section 7.09.Successor Trustee by Merger.If the Trustee consolidates with, merges or converts into, or
transfers all or substantially all its corporate trustee business or assets to, another corporation, the resulting, surviving or transferee corporation without any further act shall be the successor
Trustee.

Section 7.10.Eligibility; Disqualification.The Trustee (or if a Trustee is a member of a bank holding
company, its bank holding company) shall have a combined capital and surplus of at least

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$50,000,000
as set forth in its most recent published annual report of conditions. If at any time the Trustee shall cease to be eligible in accordance with the provisions of this Section, it shall
resign immediately in the manner and with the effect hereinafter specified in this Article.

Section 7.11.Preferential Collection of Claims Against Company.If and when the Trustee shall be or
become a creditor of the Company (or any other obligor upon the Securities), the Trustee shall be subject to the provisions of the TIA regarding the collection of claims against the Company (or any
such other obligor).

Section 7.12.Reports by Trustee.

(a)   The
Trustee shall transmit to Holders such reports concerning the Trustee and its actions under this Indenture as may be required pursuant to the TIA at the times and in
the manner provided pursuant thereto.

(b)   A
copy of each such report shall, at the time of such transmission to Holders, be filed by the Trustee with each stock exchange or market upon which the Securities are
listed, with the Commission and with the Company. The Company will notify the Trustee when the Securities are listed on any stock exchange or market.

ARTICLE 8  DISCHARGE OF INDENTURE

Section 8.01.Discharge of Liability on Securities.When (i) the Company delivers to the Trustee
all outstanding Securities (other than Securities replaced pursuant to Section 2.07) for cancellation or (ii) all outstanding Securities have become due and payable and the Company
deposits with the Trustee cash and/or securities, as, permitted by the terms hereof, sufficient to pay at Stated Maturity the principal amount of all outstanding Securities (other than Securities
replaced pursuant to Section 2.07), and if in either case the Company pays all other sums payable hereunder by the Company, then this Indenture shall, subject to Section 7.07, cease to
be of further effect. The Trustee shall join in the execution of a document prepared by the Company acknowledging satisfaction and discharge of this Indenture on demand of the Company accompanied by
an Officers' Certificate and Opinion of Counsel and at the cost and expense of the Company.

Section 8.02.Repayment to the Company.The Trustee and the Paying Agent shall return to the Company upon
written request any money or securities held by them for the payment of any amount with respect to the Securities that remains unclaimed for two years, provided, however, that the Trustee or such
Paying Agent, before being required to make any such return, shall at the expense of the Company cause to be published once in a newspaper of general circulation in The City of New York or mail to
each such Holder notice that such money or securities remains unclaimed and that, after a date specified therein, which shall not be less than 30 days from the date of such publication or
mailing, any unclaimed money or securities then remaining will be returned to the Company. After return to the Company, Holders entitled to the money or securities must look to the Company for payment
as general creditors unless an applicable abandoned property law designates another person.

ARTICLE 9  AMENDMENTS

Section 9.01.Without Consent of Holders.The Company and the Trustee may amend this Indenture or the
Securities without the consent of any Securityholder:



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Section 9.02.With Consent of Holders.With the written consent of the Holders of at least a majority in
aggregate principal amount of the Securities at the time outstanding, the Company and the Trustee may amend this Indenture or the Securities. However, without the consent of each Securityholder
affected, an amendment or supplement to this Indenture or the Securities may not:



and
no such amendment or supplement to this Indenture may reduce the aforesaid percentage of Securities whose Holders must consent to any such amendment or supplemental indenture, without the comment
of the Holders of all the Securities then outstanding.

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

After
an amendment under this Section 9.02 becomes effective, the Company shall mail to each Holder a notice briefly describing the amendment.

Section 9.03.Compliance with TIA.Every supplemental indenture executed pursuant to this Article shall
comply with the TIA as then in effect.

Section 9.04.Revocation and Effect of Consents, Waivers and Actions.Until an amendment, supplemental
indenture, waiver or other action becomes effective, a consent to it or any other action by a Holder of a Security hereunder is a continuing consent by the Holder and every subsequent Holder of that
Security or portion of the Security that evidences the same obligation as the consenting Holder's Security, even if notation of the consent, waiver or action is not made on the Security. However, any
such Holder or subsequent Holder may revoke the consent, waiver or action as to such Holder's Security or portion of the Security if the Trustee receives the notice or revocation before the date the
amendment, supplemental indenture, waiver or action becomes effective. After an amendment, supplemental indenture, waiver or action becomes effective, it shall bind every Securityholder.

Section 9.05.Notation on or Exchange of Securities.Securities authenticated and delivered after the
execution of any supplemental indenture pursuant to this Article may, and shall if required by the

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Trustee,
bear a notation in form approved by the Trustee as to any matter provided for in such supplemental indenture. If the Company shall so determine, new Securities so modified as to conform, in
the opinion of the Trustee and the Board of Directors, to any such supplemental indenture may be prepared and executed by the Company and authenticated and delivered by the Trustee in exchange for
outstanding Securities.

Section 9.06.Trustee to Sign Supplemental Indentures.The Trustee shall sign any supplemental indenture
authorized pursuant to this Article 9 if the amendment does not adversely affect the rights, duties, liabilities or immunities of the Trustee. If it does, the Trustee may, but need not, sign
such supplemental indenture. In signing such supplemental indenture the Trustee shall be entitled to receive, and (subject to the provisions of Section 7.01) shall be fully protected in relying
upon, an Officers' Certificate and an Opinion of Counsel stating that such supplemental indenture is authorized or permitted by this Indenture.

Section 9.07.Effect of Supplemental Indentures.Upon the execution of any supplemental indenture under
this Article, this Indenture shall be modified in accordance therewith, and such supplemental indenture shall form a part of this Indenture for all purposes; and every Holder of Securities
theretofore or thereafter authenticated and delivered hereunder shall be bound thereby.

ARTICLE 10  CONVERSION

Section 10.01.Conversion Privilege.A Holder of a Security may convert such Security into Common Stock
at any time during the period stated in paragraph 7 of the Securities. The conversion price per share of Common Stock (the "Conversion Price") shall be that set forth in paragraph 7 in
the Securities, subject to adjustment as herein set forth.

A
Holder may convert a portion of the principal amount of a Security if the portion is $1,000 or a multiple of $1,000. Provisions of this Indenture that apply to conversion of all of a
Security also apply to conversion of a portion of a Security.

Section 10.02.Conversion Procedure.To convert a Security a Holder must satisfy the requirements in
paragraph 7 of the Securities. The date on which the Holder satisfies all those requirements is the conversion date (the "Conversion Date"). Securities surrendered for conversion during the
period from the close of business on any Regular Record Date to the close of business on the Trading Day immediately prior to the next succeeding Interest Payment Date (the "Interest Period") shall
(except in the case of Securities or portions thereof which have been called for redemption on a Redemption Date within such Interest Period) be accompanied by payment in New York Clearing House funds
or other funds acceptable to the Company of an amount equal to the interest payable on such Interest Payment Date on the principal amount of Securities being surrendered for conversion. Subject to the
provisions of Section 3.07 relating to the payment of Defaulted Interest by the Company, the interest payment with respect to a Security surrendered for conversion during the Interest Period
(except in the case of Securities or portions thereof which have been called for redemption on a Redemption Date within the Interest Period) shall be payable on such Interest Payment Date to the
Holder of such Securities at the close of business on such Regular Record Date notwithstanding the conversion of such Securities during such Interest Period.

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As soon as practicable after the Conversion Date, the Company shall deliver to the Holder, through the Conversion Agent, a certificate for the number of full shares of Common Stock
issuable upon the conversion and cash in lieu of any fractional share determined pursuant to Section 10.03. The person in whose name the certificate is registered shall be treated as a
stockholder of record on and after the Conversion Date; provided, however, that no surrender of a Security on any date when the stock transfer books of the Company shall be closed shall be effective
to constitute the person or persons entitled to receive the shares of Common Stock upon such conversion as the record holder or holders of such shares of Common Stock on such date, but such surrender
shall be effective to constitute the person or persons entitled to receive such shares of Common Stock as the record holder or holders thereof for all purposes at the close of business on the next
succeeding day on which such stock transfer books are open; such conversion shall be at the Conversion Price in effect on the date that such Security shall have been surrendered for conversion, as if
the stock transfer books of the Company had not been closed. Upon conversion of a Security, such person shall no longer be a Holder of such Security.

No
payment or adjustment will be made for dividends on or other distribution with respect to any Common Stock except as provided in this Article 10.

If
the Holder converts more than one Security at the same time, the number of shares of Common Stock issuable upon the conversion shall be based on the total principal amount of the
Securities converted.

Upon
surrender of a Security that is converted in part, the Company shall execute, and the Trustee shall authenticate and deliver to the Holder, a new Security in an authorized
denomination equal in principal amount to the unconverted portion of the Security surrendered.

If
the last day on which a Security may be converted is a Legal Holiday in a place where a Conversion Agent is located, the Security may be surrendered to that Conversion Agent on the
next succeeding day that it is not a Legal Holiday.

Section 10.03.Fractional Shares.The Company will not issue a fractional share of Common Stock upon
conversion of a Security. Instead, the Company will deliver cash for the current market value of the fractional share. The current market value of a fractional share shall be determined to the nearest
1/10,000th of a share by multiplying the last reported sale price (determined as set forth in the definition of Current Market Price), on the last Trading Day prior to the Conversion Date, of a full
share by the fractional amount and rounding the product to the nearest whole cent.

Section 10.04.Taxes on Conversion.If a Holder converts a Security, the Company shall pay any
documentary, stamp or similar issue or transfer tax due on the issue of shares of Common Stock upon the conversion. However, the Holder shall pay any such tax which is due because the Holder requests
the shares to be issued in a name other than the Holder's name. The Conversion Agent may refuse to deliver the certificates representing the Common Stock being issued in a name other than the Holder's
name until the Conversion Agent receives a sum sufficient to pay any tax which will be due because the shares are to be issued in a name other than the Holder's name. Nothing herein shall preclude any
tax withholding required by law or regulations.

Section 10.05.Company to Provide Stock.The Company shall, prior to issuance of any Securities
hereunder, and from time to time as may be necessary, reserve out of its authorized but unissued Common Stock a sufficient number of shares of Common Stock to permit the conversion of the Securities.

All
shares of Common Stock delivered upon conversion of the Securities shall be newly issued shares or treasury shares, shall be duly and validly issued and fully paid and nonassessable
and shall be free from preemptive rights and free of any lien or adverse claim.

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The
Company will endeavor promptly to comply with all Federal and state securities laws regulating the offer and delivery of shares of Common Stock upon conversion of Securities, if any,
and will endeavor promptly, if permitted by the rules of such exchange, over-the-counter market or other market, to list or cause to have quoted such shares of Common Stock on
each national securities exchange or in the over-the-counter market or such other market on which the Common Stock is then listed or quoted.

Section 10.06.Adjustment for Change in Capital Stock.In case the Company shall (i) pay a
dividend, or make a distribution, in shares of its Common Stock, on its Common Stock, (ii) subdivide its outstanding Common Stock into a greater number of shares, or (iii) combine its
outstanding Common Stock into a smaller number of shares, the Conversion Price in effect immediately prior thereto shall be adjusted so that the holder of any Security thereafter surrendered for
conversion shall be entitled to receive the number of shares of Common Stock of the Company which he would have owned or have been entitled to receive after the happening of any of the events
described above had such Security been converted immediately prior to the happening of such event. If any dividend or distribution of the type described in clause (i) above is not so paid or
made, the Conversion Price shall again be adjusted to the Conversion Price which would then be in effect if such dividend or distribution had not been declared. An adjustment made pursuant to this
Section 10.06 shall become. effective immediately after the record date in the case of a dividend and shall become effective immediately after the effective date in the case of subdivision or
combination.

Section 10.07.Adjustment for Rights Issue.In case the Company shall issue rights or warrants to all
holders of its Common Stock entitling them (for a period expiring within 45 days after the record date mentioned below) to subscribe for or purchase Common Stock at a price per share less than
the Current Market Price per share of Common Stock at the record date for the determination of stockholders entitled to receive such rights or warrants, the Conversion Price in effect immediately
prior thereto shall be adjusted so that the same shall equal the Conversion Price determined by multiplying the Conversion Price in effect immediately prior to the date of issuance of such rights or
warrants by a fraction of which the numerator shall be the number of shares of Common Stock outstanding on the date of issuance of such rights or warrants plus the number of shares which the aggregate
offering price of the total number of shares so offered would purchase at such Current Market Price, and of which the denominator shall be the number of shares of Common Stock outstanding on the date
of issuance of such rights or warrants plus the number of additional shares of Common Stock offered for subscription or purchase. Such adjustment shall be made successively whenever any such rights or
warrants are issued, and shall become effective immediately after the opening of business on the day following the record date for the determination of the 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 Price shall be readjusted to the Conversion Price which 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. If such
rights or warrants are not so issued, the Conversion Price shall again be adjusted to be the Conversion Price which would then be in effect if such record date 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, the value of such consideration, if other than cash, to be determined by the Board of Directors.

Section 10.08.Adjustment for Other Distributions.(a) In case the Company shall distribute to
all holders of its Common Stock (excluding any distribution in connection with the liquidation, dissolution or winding up of the Company, whether voluntary or involuntary) any shares of any class of
capital

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stock
of the Company (other than Common Stock) or evidences of its indebtedness or assets (other than cash) or rights or warrants to subscribe for or purchase any of its securities (excluding those
referred to in Section 10.07 hereof) (any of the foregoing hereinafter in this Section 10.08(a) called the "Distributed Securities"), then, in each case, the Conversion Price shall be
adjusted so that the same shall equal the Conversion Price determined by multiplying the Conversion Price in effect immediately prior to the date of such distribution by a fraction of which the
numerator shall be the Current Market Price per share of the Common Stock on the record date mentioned below less the fair market value on such record date (as determined by the Board of Directors of
the Company, whose determination shall be conclusive, and described in a certificate filed with the Trustee) of the Distributed Securities so distributed applicable to one share of Common Stock, and
the denominator shall be the Current Market Price per share of the Common Stock on such record date. Such adjustment shall become effective immediately after the record date for the determination of
stockholders entitled to receive such distribution. Notwithstanding the foregoing, in the event the then fair market value (as so determined) of the portion of the Distributed 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 relevant record date, in lieu of the foregoing adjustment, adequate
provision shall be made so that each Securityholder shall have the right to receive upon conversion the amount of Distributed Securities such Holder would have received had such Holder converted each
Security on such record date. In the event that such distribution is not so paid or made, the Conversion Price shall again be adjusted to the Conversion Price which would then be in effect if such
distribution had not been declared. If the Board of Director determines the fair market value of any distribution for purposes of this Section 10.08(a) 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.

Notwithstanding
the foregoing provisions of this Section 10.08(a), no adjustment shall be made thereunder for any distribution of Distributed Securities if the Company makes
proper provision so that each Holder of a Security who converts such Security (or any portion thereof) after the record date for such distribution shall be entitled to receive upon such conversion, in
addition to the shares of Common Stock issuable upon such conversion, the amount and kind of Distributed Securities that such Holder would have been entitled to receive if such Holder had, immediately
prior to such record date, converted such Security into Common Stock, provided that, with respect to any Distributed Securities that are convertible, exchangeable or exercisable, the foregoing
provision shall only apply to the extent (and so long as) the Distributed Securities receivable upon conversion of such Security would be convertible, exchangeable or exercisable, as applicable,
without any loss of rights or privileges for a period of at least 60 days following conversion of such Security.

(b)   In
case the Company shall, by dividend or otherwise, distribute to all holders of its Common Stock cash (excluding (x) any quarterly cash dividend on the Common
Stock to the extent the aggregate cash dividend per share of Common Stock in any fiscal quarter does not exceed the greater of (A) the amount per share of Common Stock of the next preceding
quarterly cash dividend on the Common Stock to the extent such preceding quarterly dividend did not require any adjustment of the Conversion Price pursuant to this Section 10.08(b) (as adjusted
to reflect subdivisions or combinations of the Common Stock), and (B) 3.75% of the average of the last reported sales prices of the Common Stock (determined as provided in the definition of
Current Market Price) during the ten Trading Days next preceding the date of declaration of such dividend and (y) any dividend or distribution in connection with the liquidation, dissolution or
winding up of the Company, whether voluntary or involuntary), then, in such case, unless the Company elects to reserve such cash for distribution to the holders of the Securities upon the conversion
of the Securities so that any such holder converting Securities will receive upon such conversion, in addition to the shares of Common Stock to which such holder is entitled, the amount of cash which
such holder would have received if such holder had, immediately prior to the record date for such distribution of cash, converted its Securities into

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Common
Stock, the Conversion Price shall be decreased so that the same shall equal the Conversion Price determined by multiplying the Conversion Price in effect immediately prior to the record date by
a fraction of which the numerator shall be the Current Market Price of the Common Stock on the record date less the amount of cash so distributed (and not excluded as provided above) applicable to one
share of Common Stock, and the denominator shall be such Current Market Price of the Common Stock, such decrease to be effective immediately prior to the opening of business on the day following 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 Securityholder shall have the right to receive upon conversion the amount of cash such
holder would have received had such holder converted each Security on the record date. If such dividend or distribution is not so paid or made, the Conversion Price shall again be adjusted to be the
Conversion Price which would then be in effect if such dividend or distribution had not been declared. If any adjustment is required to be made as set forth in this Section 10.08(b) as a result
of a distribution that is a quarterly dividend, such adjustment shall be based upon the amount by which such distribution exceeds the amount of the quarterly cash dividend permitted to be excluded
pursuant hereto. If an adjustment is required to be made as set forth in this Section 10.08(b) above as a result of a distribution that is not a quarterly dividend, such adjustment shall be
based upon the full amount of the distribution.

(c)   In
case a tender or exchange offer made by the Company or any Subsidiary of the Company for all or any portion of the Common Stock shall expire and such tender or
exchange offer shall involve the payment by the Company or such Subsidiary of consideration per share of Common Stock having a fair market value (as. determined by the Board of Directors or, to the
extent permitted by applicable law, a duly authorized committee thereof, whose determination shall be conclusive, and described in a resolution of the Board of Directors or such duly authorized
committee thereof, as the case may be, at the last time (the "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 Expiration Time, the Conversion Price shall be decreased so that the same shall equal the Conversion Price
determined by multiplying the Conversion Price in effect immediately prior to the Expiration Time by a fraction of which the numerator shall be the number of shares of Common Stock outstanding
(including any tendered or exchanged shares) on the Expiration Time multiplied by the Current Market Price of the Common Stock on the Trading Day next succeeding the Expiration Time, and the
denominator 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 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) on the Expiration Time and the Current Market Price of
the Common Stock on the Trading Day next succeeding the Expiration Time, such decrease 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 or exchange offer, but the Company is permanently prevented by applicable law from effecting any such purchases or
all such purchases are rescinded, the Conversion Price shall again be adjusted to be the Conversion Price which would then be effect if such tender or exchange offer had not been made.

(d)   In
case of a tender or exchange offer made by a Person other than the Company or any Subsidiary for an amount which increases the offeror's ownership of Common Stock to
more than 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) at the last

30

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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 Price
shall be decreased so that the same shall equal the Conversion Price determined by multiplying the Conversion Price in effect immediately prior to the Offer Expiration Time by a fraction of which the
numerator shall be the number of shares of Common Stock outstanding (including any tendered or exchanged shares) on the Offer Expiration Time multiplied by the Current Market Price of the Common Stock
on the Trading Day next succeeding the Offer Expiration Time, and the denominator 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) on the Offer Expiration Time and the Current Market Price of the Common Stock on the Trading Day next succeeding the Expiration Time, such decrease to
become effective immediately prior to the opening of business on the 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 Price shall again be adjusted to be
the Conversion Price which would then be in effect if such tender or exchange offer had not been made. Notwithstanding the foregoing, the adjustment described in this Section 10.08(d) 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 5.

Section 10.09.When Adjustment May be Deferred.No adjustment in the Conversion Price need be made unless
the adjustment would require an increase or decrease of at least 1% in the Conversion Price. Any adjustments that are not made shall be carried forward and taken into account in any subsequent
adjustment.

All
calculations under this Article 10 shall be made to the nearest cent or to the nearest 1/10,000th of a share, as the case may be.

Section 10.10.When no Adjustment Required.No adjustment need be made for rights to purchase Common
Stock pursuant to a Company plan for reinvestment of dividends or interest.

No
adjustment need be made for a change in the par value or no par value of the Common Stock.

To
the extent the Securities 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.

Section 10.11.Notice of Adjustment.Whenever the Conversion Price is adjusted, the Company shall
promptly mail to Securityholders a notice of the adjustment. The Company shall file with the Trustee and the Conversion Agent such notice. The certificate shall, absent manifest error, be conclusive
evidence that the adjustment is correct. Neither the Trustee nor any Conversion Agent shall be under any duty or responsibility with respect to any such certificate except to exhibit the same to any
Holder desiring inspection thereof.

Section 10.12.Voluntary Decrease.The Company may make such decreases in the Conversion Price, in
addition to those required by Sections 10.06, 10.07 and 10.08, 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

31

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law,
the Company from time to time may decrease the Conversion Price by any amount for any period of time if the period is at least 20 days, the decrease is irrevocable during the period and
the Board of Directors shall have made a determination that such decrease would be in the best interests of the Company, which determination shall be conclusive. Whenever the Conversion Price is so
decreased, the Company shall mail to Securityholders and file with the Trustee and the Conversion Agent a notice of the decrease. The Company shall mail the notice at least 15 days before the
date the decreased Conversion Price takes effect. The notice shall state the decreased Conversion Price and the period it will be in effect.

Section 10.13.Notice of Certain Transactions.If:



then
the Company shall mail to Securityholders and file with the Trustee and the Conversion Agent a notice stating the proposed record date for a dividend or distribution or the proposed effective
date of a subdivision, combination, reclassification, consolidation, merger, sale, transfer, dissolution, liquidation or winding-up. The Company shall file and mail the notice at least
15 days before such date. Failure to file or mail the notice or any defect in it shall not affect the validity of the transaction.

Section 10.14.Effect of Reclassification, Consolidation, Merger or Sale.If any of the following events
occur, namely (i) any reclassification or change of outstanding shares of Common Stock (other than a change in par value, or from par value to no par value, or from no par value to par value,
or as a result of a subdivision or combination), (ii) any consolidation, merger or combination of the Company with another corporation as a result of which holders of Common Stock shall be
entitled to receive stock, 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 the properties and
assets of the Company as, or substantially as, an entirety to any other corporation as a result of which holders of Common Stock shall be entitled to receive stock, 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 corporation, as the case may be, shall execute with the Trustee a
supplemental indenture providing that each Security shall be convertible into the kind and amount of shares of stock and other securities or 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 Securities immediately prior to such
reclassification, change, consolidation, merger, combination, sale or conveyance. 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.

The
Company shall cause notice of the execution of such supplemental indenture to be mailed to each holder of Securities at his address appearing on the Security register provided for in
Section 2.03 of this Indenture.

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

If
this Section applies, neither Section 10.06, 10.07 nor 10.08 applies.

Section 10.15.Company Determination Final.Any determination that the Company or the Board of Directors
must make pursuant to Section 10.03, 10.06, 10.07, 10.08, 10.09, 10.10, 10.14 or 10.17 is conclusive.

32

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Section 10.16.Trustee's Adjustment Disclaimer.The Trustee has no duty to determine when an adjustment
under this Article 10 should be made, how it should be made or what it should be. The Trustee has no duty to determine whether a supplemental indenture under Section 10.14 need be
entered into or whether any provisions of any supplemental indenture are correct. The Trustee shall not be accountable for and makes no representation as to the validity or value of any securities or
assets issued upon conversion of Securities. The Trustee shall not be responsible for the Company's failure to comply with this Article 10. Each Conversion Agent shall have the same protection
under this Section 10.16 as the Trustee.

Section 10.17.Simultaneous Adjustments.In the event that this Article 10 requires adjustments to
the Conversion Price under more than one of Sections 10.06, 10.07, 10.08(a) or 10.08(b), and the record dates for the distributions giving rise to such adjustments shall occur on the same date, then
such adjustments shall be made by applying, first, the provisions of Section 10.08(a), second, the provisions of Section 10.08(b), third the provisions of Section 10.06 and,
fourth, the provisions of Section 10.07.

Section 10.18.Successive Adjustments.After an adjustment to the. Conversion Price under this
Article 10, any subsequent event requiring an adjustment under this Article 10 shall cause an adjustment to the Conversion Price as so adjusted.

Section 10.19.Rights Issued in Respect of Common Stock Issued Upon Conversion.Each share of Common
Stock issued upon conversion of Securities pursuant to this Article 10 shall be entitled to receive the appropriate number of Rights, if any, and the certificates representing the Common Stock
issued upon such conversion shall bear such legends, if any, in each case as provided by and subject to the terms of the Rights Agreement as in effect at the time of such conversion. If the Rights are
separated from the Common Stock in accordance with the provisions of the Rights Agreement such that the Holders of Securities would thereafter not be entitled to receive any such Rights in respect to
the Common Stock issuable upon conversion of such Securities, the Conversion Price will be adjusted as provided in Section 10.08(a) on the separation date; provided that if such Rights expire,
terminate or are redeemed by the Company, the Conversion Price shall again be adjusted to be the Conversion Price which would then be in effect if such separation had not occurred. In lieu of any such
adjustment, the Company may amend the Rights Agreement to provide that upon conversion of the Securities the Holders will receive, in addition to the Common Stock issuable upon such conversion, the
Rights which would have attached to such shares of Common Stock if the Rights had not become separated from the Common Stock pursuant to the provisions of the Rights Agreement.

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"):



shall
not be deemed distributed for purposes of Section 10.08(a) until the occurrence of the earliest Trigger Event. In addition, in the event of any distribution of rights or warrants, or any
Trigger Event with respect thereto, that shall have resulted in an adjustment to the Conversion Price under Section 10.08(a), (1) in the case of any such rights or warrants which shall
all have been redeemed or repurchased without exercise by any holders thereof, the Conversion Price 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 of Common Stock with respect to such rights or
warrants (assuming such holder

33

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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 any such rights or warrants all of which shall
have expired without exercise by any holder thereof, the Conversion Price shall be readjusted as if such issuance had not occurred.

Section 10.20.General Considerations.Whenever successive adjustments to the Conversion Price are called
for pursuant to this Article 10, such adjustments shall be made to the Current Market Price as may be necessary or appropriate to effectuate the intent of this Article and to avoid unjust or
inequitable results as determined in good faith by the Board of Directors.

ARTICLE 11  MISCELLANEOUS

Section 11.01.Conflict with TIA.If any provision hereof limits, qualifies or conflicts with a provision
of the TIA that is required under the TIA to be a part of and govern this Indenture, the latter provision shall control. If any provision of this Indenture modifies or excludes any provision of the
TIA that may be so modified or excluded, the latter provision shall be deemed to apply to this Indenture as so modified or excluded, as the case may be.

Section 11.02.Notices.Any request, demand, authorization, notice, waiver, consent or communication
shall be in writing and delivered in person or mailed by first class mail, postage prepaid, addressed as follows or transmitted by facsimile transmission (confirmed by overnight courier) to the
following facsimile numbers:

if
to the Company:



if
to the Trustee:



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

Any
notice or communication given to a Securityholder shall be mailed to the Securityholder, by first class mail, postage prepaid, at the Securityholder's address as it appears on the
registration books of the Registrar and shall be sufficiently given if so mailed within the time prescribed.

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

34

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If
the Company mails a notice or communication to the Securityholders, it shall mail a copy to the Trustee and each Registrar, Paying Agent, Conversion Agent or co-registrar.

Section 11.03.Communication by Holders with other Holders.Securityholders may communicate pursuant to
TIA Section 312(b) with other Securityholders with respect to their rights under this Indenture or the Securities. The Company, the Trustee, the Registrar, the Paying Agent, the Conversion
Agent and anyone else shall have the protection of TIA Section 312(c).

Section 11.04.Certificate and Opinion as to Conditions Precedent.Upon any request or application by the
Company to the Trustee to take any action under this Indenture, the Company shall furnish to the Trustee:



Section 11.05.Statements Required in Certificate or Opinion.Each Officers' Certificate or Opinion of
Counsel with respect to compliance with a covenant or condition provided for in this Indenture shall include:



Section 11.06.Separability Clause.In case any provision in this Indenture or in the Securities shall be
invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.

Section 11.07.Rules by Trustee, Paying Agent, Conversion Agent and Registrar.The Trustee may make
reasonable rules for action by or a meeting of Securityholders. The Registrar, Conversion Agent and the Paying Agent may make reasonable rules for their functions.

Section 11.08.Legal Holidays.A "Legal Holiday" is any day other than a Business Day. If any specified
date (including a date for giving notice) is a Legal Holiday, the action shall be taken on the next succeeding day that is not a Legal Holiday, and, to the extent applicable, no interest, if any,
shall accrue for the intervening period.

Section 11.09.Governing Law.THE LAWS OF THE STATE OF NEW YORK SHALL GOVERN THIS INDENTURE AND THE
SECURITIES.

Section 11.10.No Recourse Against Others.A director, officer, employee or stockholder, as such, of the
Company shall not have any liability for any obligations of the Company under the Securities or this Indenture or for any claim based on, in respect of or by reason of such obligations or their
creation. By accepting a Security, each Securityholder shall waive and release all such liability. The waiver and release shall be part of the consideration for the issue of the Securities.

35

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Section 11.11.Successors.All agreements of the Company in this Indenture and the Securities shall bind
its successor. All agreements of the Trustee in this Indenture shall bind its successor.

Section 11.12.Multiple Originals.The parties may sign any number of copies of this Indenture. Each
signed copy shall be an original, but all of them together represent the same agreement. One signed copy is enough to prove this Indenture.

36

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IN
WITNESS WHEREOF, the undersigned, being duly authorized, have executed this Indenture on behalf of the respective parties hereto as of the date first written above.

|                        |  | SILICON GRAPHICS, INC.                                     
|----------------------- |  | -----------------------------------------------------------
|                        |  | By:                                                        
|Attest:                 |  |                                                            
|/s/ Sandra EscherTitle: |  |                                                            
|[SEAL]                  |  |                                                            
|                        |  | STATE STREET BANK AND TRUST
    COMPANY OF CALIFORNIA, N.A.
|                        |  | By:                                                        

---

IN
WITNESS WHEREOF, the undersigned, being duly authorized, have executed this Indenture on behalf of the respective parties hereto as of the date first written above.

|        |  | SILICON GRAPHICS, INC.                                     
|------- |  | -----------------------------------------------------------
|        |  | By:                                                        
|Attest: |  |                                                            
|Title:  |  |                                                            
|[SEAL]  |  |                                                            
|        |  | STATE STREET BANK AND TRUST
    COMPANY OF CALIFORNIA, N.A.
|        |  | By:                                                        

---



EXHIBIT A  [FORM OF FACE OF SECURITY]

[FORM
OF LEGEND FOR GLOBAL SECURITY:

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

SILICON GRAPHICS, INC.
51/4% SENIOR CONVERTIBLE NOTE DUE 2004

|No. |  | $    
|--- |  | -----
|    |  | CUSIP

Silicon
Graphics, Inc., a Delaware corporation, promises to pay to  or registered assigns, the
principal amount of
 Dollars ($            ) on
September 1, 2004 and to pay interest thereon from September 4, 1997 or from the most recent Interest Payment
Date to which interest has been paid or duly provided for, semi-annually on March 1 and September 1 in each year, commencing March 1, 1998, at the rate of
51/4% per annum until the principal hereof is paid or made available for payment. The interest so payable, and punctually paid or duly provided for, on any Interest Payment Date will,
as provided in such Indenture, be paid to the Person in whose name this Security (or one or more Predecessor Securities) is registered at the close of business on the Regular Record Date for such
interest, which shall be the February 15 or August 15 (whether or not a Business Day), as the case may be, next preceding such Interest Payment Date. Any such interest not so punctually
paid or duly provided for will forthwith cease to be payable to the Holder on such Regular Record Date and may either be paid to the Person in whose name this Security (or one or more Predecessor
Securities) is registered at the close of business on a Special Record Date for the payment of such Defaulted Interest to be fixed by the Trustee, notice whereof shall be given to Holders of
Securities not less than 10 days prior to such Special Record Date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange or other
market on which the Securities may be listed, and upon such notice as may be required by such exchange or market, all as more fully provided in said Indenture. Payment of the principal of (and
premium, if any) and interest on this Security will be made at the Corporate Trust Office or the office or agency of the Company maintained for that purposes in the Borough of Manhattan, The City of
New York, New York in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts; provided, however, that at the option of
the Company payment of interest may be made by check mailed to the address o f or by wire transfer to the account of, the Person entitled thereto as such address shall appear in the Security Register.

Additional
provisions of this Security are set forth on the other side of this Security.

A-1

---

IN
WITNESS WHEREOF, Silicon Graphics, Inc. has caused this instrument to be duly executed under its corporate seal.

|                                                                             |  |                      |  | SILICON GRAPHICS, INC.
|---------------------------------------------------------------------------- |  | -------------------- |  | ----------------------
|                                                                             |  |                      |  | By:                   
|[SEAL]                                                                       |  |                      |  |                       
|Attest:                                                                      |  |                      |  |                       
|Dated:                                                                       |  |                      |  |                       
|TRUSTEE'S CERTIFICATE OF AUTHENTICATION                                      |  |                      |  |                       
|This is one of the Securities referred to in the within mentioned Indenture. |  |                      |  |                       
|STATE STREET BANK AND TRUST COMPANY
    OF CALIFORNIA, N.A as Trustee,       |  |                      |  |                       
|By:                                                                          |  | Authorized Signatory |  |                       

A-2

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[FORM OF REVERSE SIDE OF SECURITY]

SILICON
GRAPHICS, INC.
51/4% SENIOR CONVERTIBLE NOTE DUE 2004

1.     Interest

This Security shall bear interest at 51/4% per annum in the manner set forth in the Indenture and the face of this Security. In the event that
principal hereof or any portion of such principal is not paid when due (whether upon acceleration pursuant to Section 6.02 of the Indenture, upon the date set for payment of the Redemption
Price pursuant to paragraph 5 hereof, upon the date set for payment of a Fundamental Change Redemption Price pursuant to paragraph 6 hereof or upon the Stated Maturity of this Security),
then in each such case the overdue amount shall bear interest at the rate of 51/4% per annum, compounded semiannually (to the extent that the payment of such interest shall be legally
enforceable), which interest shall accrue from the date such overdue amount was due to the date payment of such amount, including interest thereon, has been made or duly provided for. All such
interest shall be payable on demand.

2.     Method of Payment

Subject to the terms and conditions of the Indenture, the Company will make payments in respect of the Securities to the persons who are registered Holders of
Securities at the close of business on the Redemption Date, Fundamental Change Repurchase Date or Stated Maturity, as the case may be. Holders must surrender Securities to a Paying Agent to collect
such payments in respect of the Securities. The Company will pay cash amounts in money of the United States that at the time of payment is legal tender for payment of public and private debts.
However, the Company may make such cash payments by check mailed to the address of, or by wire transfer to the account of, the person entitled to such payment.

3.     Paying Agent, Conversion Agent and Registrar

Initially, State Street Bank and Trust Company of California, N.A., a national banking association (the "Trustee"), will act as Paying Agent, Conversion Agent and
Registrar. The Company may appoint and change any Paying Agent, Conversion Agent, Registrar or co-registrar without notice,
other than notice to the Trustee. The Company or any of its Subsidiaries or any of their Affiliates may act as Paying Agent, Conversion Agent, Registrar or co-registrar.

4.     Indenture

The Company issued the Securities under an Indenture dated as of September 1, 1997 (the "Indenture"), between the Company and the Trustee. Capitalized
terms used herein and not defined herein have the meanings ascribed thereto in the Indenture. The Securities are subject to all such terms, and Securityholders are referred to the Indenture for a
statement of those terms.

The
Securities are general unsecured obligations of the Company limited to $234,609,000 aggregate principal amount (subject to Sections 2.02 and 2.07 of the Indenture).

5.     Redemption at the Option of the Company

Prior to September 7, 2000, the Securities will not be redeemable at the option of the Company. Beginning on September 7, 2000, the Company may
redeem the Securities for cash as a whole at any time, or from time to time in part, upon not less than 30 days' nor more than 60 days' notice at the following prices (the "Redemption
Price") (expressed as percentages of the principal amount), together with accrued and unpaid interest to, but excluding, the Redemption Date, except that on or after

A-3

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September 7,
2000 and prior to September 7, 2002, the Securities will not be redeemable at the option of the Company unless the Closing Price of the Common Stock shall have exceeded 140%
of the Conversion Price then in effect for 20 Trading Days within a period of 30 consecutive Trading Days ending within five Trading Days prior to the notice of redemption.

If
redeemed during the 12-month period beginning September 1 (beginning September 7, 2000 and ending on August 31, 2001, in the case of the first such
period):

Year

Redemption Price2000

103.00%2001

102.252002

101.502003

100.75


and
100% at September 1, 2004; provided that if such Redemption Date is an Interest Payment Date, then the interest payable on such date shall be paid to the Holder of the Security on the next
preceding Regular Record Date. No Securities may be redeemed by the Company if an Event of Default with respect to the payment of interest on the Securities has occurred and is continuing.

No
sinking fund is provided for the Securities.

Notice
of redemption at the option of the Company will be mailed at least 30 days but not more than 60 days before the Redemption Date to each Holder of Securities to be
redeemed at the Holder's registered address. If money sufficient to pay the Redemption Price, together with accrued interest to, but excluding, the Redemption Date, of all Securities (or portions
thereof) to be redeemed on the Redemption Date is deposited with the Paying Agent prior to or on the Redemption Date, on and after such date interest ceases to accrue on such Securities or portions
thereof Securities in denominations larger than $1,000 of principal amount may be redeemed in part but only in multiples of $1,000 of principal amount.

6.     Redemption at the Option of the Holder Upon a Fundamental Change

(a)   At
the option of the Holder and subject to the terms and conditions of the Indenture, the Company shall become obligated to redeem the Securities held by such Holder on
the date (the "Fundamental Change Repurchase Date") (or if such date is not a Business Day, the next succeeding Business Day) that is 45 days after the date of the Company's notice of such
Fundamental Change (as defined in the Indenture) occurring on or prior to September 1, 2004 at the following prices (expressed as percentages of the principal amount) in the event of a
Fundamental Change Repurchase Date occurring during the 12-month period beginning September 1:

Year

Percentage

Year

Percentage1997

105.25%

2001

102.25%1998

104.50

2002

101.501999

103.75

2003

100.752000

103.00


and
100% at September 1, 2004; provided in each case that if the Applicable Price (as defined in the Indenture) is less than the Reference Market Price (as defined in the Indenture), the
Company shall redeem such Securities at a price equal to the foregoing repayment price multiplied by the fraction obtained by dividing the Applicable Price by the Reference Market Price. In each case,
the Company shall also pay accrued interest, if any, on such Securities to, but excluding, the Fundamental Change Repurchase Date; provided that if such Fundamental Change Repurchase Date is an
Interest Payment Date, then the interest payable on such date shall be paid to the Holder of the Security on the next preceding Regular Record Date. Securities in denominations larger than $1,000 of
principal amount

A-4

---

may
be redeemed in part in connection with a Fundamental Change, but only in multiples of $1,000 of principal amount.

(b)   Holders
have the right to withdraw any Fundamental Change Redemption Notice by delivering to the Paying Agent a written notice of withdrawal in accordance with the
provisions of the Indenture.

(c)   If
cash sufficient to pay the Fundamental Change Redemption Price, together with accrued interest to, but excluding, the Fundamental Change Repurchase Date, of all
Securities or portions thereof to be purchased as of the Fundamental Change Repurchase Date is deposited with the Paying Agent on or prior to the Fundamental Change Repurchase Date, interest ceases to
accrue on such Securities (or portions thereof) on and after the Fundamental Change Repurchase Date, and the Holder thereof shall have no other rights as such (other than the right to receive the
Fundamental Change Redemption Price, together with accrued interest to, but excluding, the Fundamental Change Repurchase Date, upon surrender of such Security).

7.     Conversion

Subject to the next two succeeding sentences, a Holder of a Security may convert it into Common Stock of the Company at any time after issuance and before the
close of business on September 1, 2004. If the Security is called for redemption, the Holder may convert it at any time before the close of the last Trading Day prior to the Redemption Date. In
the event the Security is surrendered during the period from the close of business on any Regular Record Date next preceding any Interest Payment Date to the close of business on the Trading Day
immediately preceding the next succeeding Interest Payment Date (except in the case of Security to be redeemed within such period), such Securities must be accompanied by payment in New York Clearing
House funds or other funds acceptable to the Company of an amount equal to the interest payable on such Interest Payment Date on the principal amount of this Security then being converted. Subject to
the aforesaid requirement for payment and, in the case of a conversion after the Regular Record Date next preceding any Interest Payment Date and on or before such Interest Payment Date, to the right
of the Holder of this Security (or any Predecessor Security) of record at such Regular Record Date to receive an installment of interest payable on such Interest Payment Date (except in the case of
Securities whose Maturity is prior to such Interest Payment Date), no payment or adjustment is to be made on conversion for interest accrued hereon or for dividends on the Common Stock issued on
conversion. A Security in respect of which a
Holder has delivered a notice of exercise of the option to redeem such Security in the event of a Fundamental Change may be converted only if the notice of exercise is withdrawn in accordance with the
terms of the Indenture.

The
initial Conversion Price is $36.25 per share of Common Stock, subject to adjustment in certain events described in the Indenture. The Company will deliver cash or a check in lieu of
any fractional share of Common Stock.

To
convert a Security a Holder must (1) complete and manually sign the conversion notice on the back of the Security (or complete and manually sign a facsimile of such notice) and
deliver such notice to the Conversion Agent, (2) surrender the Security to a Conversion Agent, (3) furnish appropriate endorsements and transfer documents if required by the Conversion
Agent, the Company or the Trustee and (4) pay any transfer or similar tax, if required.

A
Holder may convert a portion of a Security if the principal amount of such portion is $1,000 or a multiple of $1,000. No payment or adjustment will be made for dividends on the Common
Stock except as provided in the Indenture.

The
Conversion Price is subject to adjustment as provided in the Indenture. In addition, in the case of (i) any reclassification of the Common Stock, or (ii) a
consolidation or merger involving the

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Company
or a sale or conveyance to another corporation of the property and assets of the Company as an entirety (or substantially as an entirety), in each case as a result of which holders of Common
Stock shall be entitled to receive stock, securities, other property or assets (including cash) with respect to or in exchange for such Common Stock, as set forth in the Indenture, or upon certain
distributions described in the Indenture, the right to convert a Security into Common Stock may be changed; as set forth in the Indenture, into a right to convert it into securities, cash or other
assets of the Company or another person.

8.     Conversion Arrangement on Call for Redemption

Any Securities called for redemption, unless surrendered for conversion before the close of business on the last Trading Day prior to the Redemption Date, may be
deemed to be purchased from the Holders of such Securities at an amount not less than the Redemption Price, together with accrued interest to, but excluding the Redemption Date, by one or more
investment bankers or other purchasers who may agree with the Company to purchase such Securities from the Holders, to convert them into Common Stock of the Company and to make payment for such
Securities to the Trustee in trust for such Holders.

9.     Denominations; Transfer; Exchange

The Securities are in registered form, without coupons, in denominations of $1,000 of principal amount and multiples of $1,000. A Holder may transfer or exchange
Securities in accordance with the Indenture. The Registrar may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and to pay any taxes and fees required
by law or permitted by the Indenture. The Registrar need not transfer or exchange any Securities selected for redemption (except, in the case of a Security to be redeemed in part, the portion of the
Security not to be redeemed) or any Securities in respect of which a Fundamental Change Redemption Notice has been given and not withdrawn (except, in the case of a Security to be purchased in part,
the portion of the Security not to be purchased) or any Securities for a period of 15 days before a selection of Securities to be redeemed.

10.   Persons Deemed Owners

The registered Holder of this Security may be treated as the owner of this Security for all purposes.

11.   Unclaimed Money or Securities

The Trustee and the Paying Agent shall return to the Company upon written request any money or securities held by them for the payment of any amount with respect
to the Securities that remains unclaimed for two years, provided, however, that the Trustee or such Paying Agent, before being required to make any such return, shall at the expense of the Company
cause to be published once in a newspaper of general circulation in The City of New York or mail to each such Holder notice that such money or securities remains unclaimed and that, after a date
specified therein, which shall not be less than 30 days from the date of such publication or mailing, any unclaimed money or securities then remaining will be returned to the Company. After
return to the Company, Holders entitled to the money or securities must look to the Company for payment as general creditors unless an applicable abandoned property law designates another person.

12.   Amendment; Waiver

Subject to certain exceptions set forth in the Indenture, (i) the Indenture or the Securities may be amended with the written consent of the Holders of at
least a majority in aggregate principal amount

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of
the Securities at the time outstanding and (ii) certain defaults or noncompliance with certain provisions may be waived with the written consent of the Holders of a majority in aggregate
principal amount of the Securities at the time outstanding. Subject to certain exceptions set forth in the Indenture, without the consent of any Securityholder, the Company and the Trustee may amend
the Indenture or the Securities to cure any ambiguity, defect or inconsistency, or to comply with Article 5 or Section 10.14 of the Indenture, to provide for uncertificated Securities in
addition to or in place of certificated Securities or to make any change that does not adversely affect the rights of any Securityholder or to comply with any requirement of the SEC in connection with
the qualification of the Indenture under the TIA.

13.   Defaults and Remedies

Under the Indenture, Events of Default include (i) default in payment of the principal amount, Redemption Price or Fundamental Change Redemption Price, as
the case may be, in respect of the Securities when the same becomes due and payable; (ii) default for 30 days in the payment of any installment of interest on the Securities;
(iii) failure by the Company to comply with other agreements in the Indenture or the Securities, subject to notice and lapse of time; and (iv) certain events of bankruptcy or insolvency.
If an Event of Default occurs and is continuing, the Trustee, or the Holders of at least 25% in aggregate principal amount of the Securities at the time outstanding, may, declare all the Securities to
be due and payable immediately. Certain events of bankruptcy or insolvency are Events of Default which will result in the Securities being declared due and payable immediately upon the occurrence of
such Events of Default.

Securityholders
may not enforce the Indenture or the Securities except as provided in the Indenture. The Trustee may refuse to enforce the Indenture or the Securities unless it receives
reasonable indemnity or security. Subject to certain limitations, Holders of a majority in aggregate principal amount of the Securities at the time outstanding may direct the Trustee in its exercise
of any trust or power. The Trustee may withhold from Securityholders notice of any continuing Default (except a Default in payment of amounts specified in clause (i) or (ii) above) if it
determines that withholding notice is in their interests.

14.   Trustee Dealings with the Company

The Trustee under the Indenture, in its individual or any other capacity, may become the owner or pledgee of Securities and may otherwise deal with and collect
obligations owed to it by the Company or
its Affiliates and may otherwise deal with the Company or its Affiliates with the same rights it would have if it were not Trustee.

15.   No Recourse Against Others

A director, officer, employee or stockholder, as such, of the Company shall not have any liability for any obligations of the Company under the Securities or the
Indenture or for any claim based on, in respect of or by reason of such obligations or their creation. By accepting a Security, each Securityholder waives and releases all such liability. The waiver
and release are part of the consideration for the issue of the Securities.

16.   Authentication

This Security shall not be valid until an authorized officer of the Trustee manually signs the Trustee's Certificate of Authentication on the other side of this
Security.

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17.   Abbreviations

Customary abbreviations may be used in the name of a Securityholder or an assignee, such as TEN COM (=tenants in common), TEN ENT (=tenants by the entireties), JT
TEN (joint tenants with right of survivorship and not as tenants in common), CUST (=custodian), and U/G/M/A (=Uniform Gift to Minors Act).

18.   Governing Law

THE LAWS OF THE STATE OF NEW YORK SHALL GOVERN THE INDENTURE AND THIS SECURITY

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The
Company will furnish to any Securityholder upon written request and without charge a copy of the Indenture which has in it the text of this Security in larger type. Requests may be
made to:



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[FORM OF CONVERSION NOTICE]

CONVERSION NOTICE

To:
Silicon Graphics, Inc.

The
undersigned registered holder of this Security hereby irrevocably exercises the option to convert this Security, or portion hereof (which is $1,000 principal amount or a multiple
thereof) below designated, into shares of Common Stock of Silicon Graphics, Inc. in accordance with the terms of the Indenture referred to in this Security, and directs that the shares issuable
and deliverable upon such conversion, together with any check in payment for fractional shares and any Securities 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 Security not converted are to be issued in the name of a person other than the undersigned,
the undersigned will pay all transfer taxes payable with respect thereto.

Dated:Signature(s)


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|Fill in for registration of shares if to be delivered, and Securities if to be issued other than to and in the name of the registered holder: |  |                                                        
|--------------------------------------------------------------------------------------------------------------------------------------------- |  | -------------------------------------------------------
|(Name)                                                                                                                                        |  |                                                        
|(Street Address)                                                                                                                              |  |                                                        
|(City, State and zip code)                                                                                                                    |  |                                                        
|Please print name and address                                                                                                                 |  |                                                        
|                                                                                                                                              |  | principal amount to be converted
(if less than all):   
|                                                                                                                                              |  | $,000                                                  
|                                                                                                                                              |  | Social Security or Other
Taxpayer Identification Number

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[FORM OF OPTION TO ELECT REDEMPTION  UPON A FUNDAMENTAL CHANGE]

To:
Silicon Graphics, Inc.

The
undersigned registered holder of this Security hereby acknowledges receipt of a notice from Silicon Graphics, Inc. (the "Company") as to the occurrence of a Fundamental Change
with respect to the Company and requests and instructs the Company to redeem this Security, or the portion hereof (which is $1,000 principal amount or a multiple thereof) below designated, in
accordance with the terms of the Indenture referred to in this Security.

Dated:Signature(s)principal amount to be redeemed
(if less than all):$,000Social Security or Other
Taxpayer Identification Number


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[FORM OF ASSIGNMENT]

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 Security and hereby irrevocably constitutes and appoints  attorney to transfer the said
Security on the books of the Company, with full power of
substitution in the premises.

Dated:Signature(s)Signature(s) must be guaranteed by a commercial bank or trust company or a member firm of a major stock exchange.Signature Guarantee


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

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