Exhibit 4.01

CHIRON
CORPORATION

Liquid
Yield Option Notes
due 2031
(Zero Coupon-Senior)

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INDENTURE
Dated as of June 12, 2001

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STATE
STREET BANK AND TRUST COMPANY OF CALIFORNIA, N.A.,

TRUSTEE

Merrill
Lynch & Co., Inc.

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CROSS REFERENCE TABLE*

TIA Section

Indenture Section310(a
)(1)
7.10(a
)(2)
N.A.(a
)(3)
N.A.(a
)(4)
N.A.(b
)
7.10(c
)
N.A.311(a
)
7.11(b
)
7.11(c
)
N.A.312(a
)
N.A.(b
)
14.03(c
)
14.03313(a
)
7.06(b
)
7.06(c
)
N.A.(d
)
7.06314(a
)
4.02(b
)
N.A.(c
)
N.A.(d
)
N.A.(e
)
N.A.(f
)
N.A.315(a
)
7.01(b
)
7.05(c
)
N.A.(d
)
7.01(e
)
6.11316(a
)(1)(A)
6.05(a
)(1)(B)
6.04(a
)(2)
N.A.(b
)
N.A.


N.A.
means Not Applicable.

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*
Note: This Cross Reference Table shall not, for any purpose, be deemed part of the Indenture.

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TABLE OF CONTENTS*

|                                                     |  |                                                                                               |  | Page
|---------------------------------------------------- |  | --------------------------------------------------------------------------------------------- |  | ----
|ARTICLE I
DEFINITIONS AND INCORPORATION BY REFERENCE
|Section 1.01                                         |  | Definitions                                                                                   |  | 1   
|Section 1.02                                         |  | Other Definitions                                                                             |  | 4   
|Section 1.03                                         |  | Incorporation by Reference of Trust Indenture Act                                             |  | 5   
|Section 1.04                                         |  | Rules of Construction                                                                         |  | 5   
|Section 1.05                                         |  | Acts of Holders                                                                               |  | 6   
|ARTICLE II
THE SECURITIES                           
|Section 2.01                                         |  | Form and Dating                                                                               |  | 7   
|Section 2.02                                         |  | Execution and Authentication                                                                  |  | 8   
|Section 2.03                                         |  | Registrar, Paying Agent, Conversion Agent, Bid Solicitation Agent and Rate Solicitation Agent |  | 8   
|Section 2.04                                         |  | Paying Agent to Hold Money and Securities in Trust                                            |  | 9   
|Section 2.05                                         |  | Securityholder Lists                                                                          |  | 9   
|Section 2.06                                         |  | Transfer and Exchange                                                                         |  | 9   
|Section 2.07                                         |  | Replacement Securities                                                                        |  | 11  
|Section 2.08                                         |  | Outstanding Securities; Determinations of Holders' Action                                     |  | 11  
|Section 2.09                                         |  | Temporary Securities                                                                          |  | 13  
|Section 2.10                                         |  | Cancellation                                                                                  |  | 13  
|Section 2.11                                         |  | Persons Deemed Owners                                                                         |  | 13  
|Section 2.12                                         |  | Global Securities                                                                             |  | 13  
|Section 2.13                                         |  | CUSIP Numbers                                                                                 |  | 17  
|ARTICLE III
REDEMPTION AND PURCHASES                
|Section 3.01                                         |  | Right to Redeem; Notices to Trustee                                                           |  | 17  
|Section 3.02                                         |  | Selection of Securities to Be Redeemed                                                        |  | 17  
|Section 3.03                                         |  | Notice of Redemption                                                                          |  | 18  
|Section 3.04                                         |  | Effect of Notice of Redemption                                                                |  | 18  
|Section 3.05                                         |  | Deposit of Redemption Price                                                                   |  | 18  
|Section 3.06                                         |  | Securities Redeemed in Part                                                                   |  | 19  
|Section 3.07                                         |  | Purchase of Securities at Option of the Holder                                                |  | 19  
|Section 3.08                                         |  | Purchase of Securities at Option of the Holder upon Change in Control                         |  | 25  
|Section 3.09                                         |  | Effect of Purchase Notice or Change in Control Purchase Notice                                |  | 27  
|Section 3.10                                         |  | Deposit of Purchase Price or Change in Control Purchase Price                                 |  | 28  
|Section 3.11                                         |  | Securities Purchased in Part                                                                  |  | 28  
|Section 3.12                                         |  | Covenant to Comply With Securities Laws Upon Purchase of Securities                           |  | 29  
|Section 3.13                                         |  | Repayment to the Company                                                                      |  | 29  

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|                                    |  |                                                   |  |   
|----------------------------------- |  | ------------------------------------------------- |  | --
|ARTICLE IV
COVENANTS               
|Section 4.01                        |  | Payment of Securities                             |  | 29
|Section 4.02                        |  | SEC and Other Reports                             |  | 29
|Section 4.03                        |  | Compliance Certificate                            |  | 30
|Section 4.04                        |  | Further Instruments and Acts                      |  | 30
|Section 4.05                        |  | Maintenance of Office or Agency                   |  | 30
|Section 4.06                        |  | Delivery of Certain Information                   |  | 30
|Section 4.07                        |  | Calculation of Original Issue Discount            |  | 30
|ARTICLE V
SUCCESSOR CORPORATION    
|Section 5.01                        |  | When Company May Merge or Transfer Assets         |  | 31
|ARTICLE VI
DEFAULTS AND REMEDIES   
|Section 6.01                        |  | Events of Default                                 |  | 32
|Section 6.02                        |  | Acceleration                                      |  | 33
|Section 6.03                        |  | Other Remedies                                    |  | 34
|Section 6.04                        |  | Waiver of Past Defaults                           |  | 34
|Section 6.05                        |  | Control by Majority                               |  | 34
|Section 6.06                        |  | Limitation on Suits                               |  | 34
|Section 6.07                        |  | Rights of Holders to Receive Payment              |  | 35
|Section 6.08                        |  | Collection Suit by Trustee                        |  | 35
|Section 6.09                        |  | Trustee May File Proofs of Claim                  |  | 35
|Section 6.10                        |  | Priorities                                        |  | 36
|Section 6.11                        |  | Undertaking for Costs                             |  | 37
|Section 6.12                        |  | Waiver of Stay, Extension or Usury Laws           |  | 37
|ARTICLE VII
TRUSTEE                
|Section 7.01                        |  | Duties of Trustee                                 |  | 37
|Section 7.02                        |  | Rights of Trustee                                 |  | 38
|Section 7.03                        |  | Individual Rights of Trustee                      |  | 39
|Section 7.04                        |  | Trustee's Disclaimer                              |  | 39
|Section 7.05                        |  | Notice of Defaults                                |  | 39
|Section 7.06                        |  | Reports by Trustee to Holders                     |  | 39
|Section 7.07                        |  | Compensation and Indemnity                        |  | 40
|Section 7.08                        |  | Replacement of Trustee                            |  | 40
|Section 7.09                        |  | Successor Trustee by Merger                       |  | 41
|Section 7.10                        |  | Eligibility; Disqualification                     |  | 41
|Section 7.11                        |  | Preferential Collection of Claims Against Company |  | 41
|ARTICLE VIII
DISCHARGE OF INDENTURE
|Section 8.01                        |  | Discharge of Liability on Securities              |  | 41
|Section 8.02                        |  | Repayment to the Company                          |  | 41

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|ARTICLE IX
AMENDMENTS               
|------------------------------------
|Section 9.01                        
|Section 9.02                        
|Section 9.03                        
|Section 9.04                        
|Section 9.05                        
|Section 9.06                        
|Section 9.07                        
|ARTICLE X
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                       
|ARTICLE XI
PAYMENT OF INTEREST      
|Section 11.01                       
|Section 11.02                       
|Section 11.03                       
|ARTICLE XII
CONTINGENT CASH INTEREST
|Section 12.01                       
|Section 12.02                       
|Section 12.03                       

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|ARTICLE XIII
CONTINGENT ADDITIONAL PRINCIPAL
|--------------------------------------------
|Section 13.01                               
|Section 13.02                               
|Section 13.03                               
|Section 13.04                               
|ARTICLE XIV
MISCELLANEOUS                   
|Section 14.01                               
|Section 14.02                               
|Section 14.03                               
|Section 14.04                               
|Section 14.05                               
|Section 14.06                               
|Section 14.07                               
|Section 14.08                               
|Section 14.09                               
|Section 14.10                               
|Section 14.11                               
|Section 14.12                               
|Section 14.13                               
|EXHIBITS                                    
|Exhibit A-1                                 
|Exhibit A-2                                 
|Exhibit B-1                                 
|Exhibit B-2                                 
|Exhibit C                                   

iv

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INDENTURE
dated as of June 12, 2001 between CHIRON CORPORATION, a Delaware corporation ("Company"), and State Street Bank and Trust Company of California, N.A., a national
banking association organized under the laws of the United States ("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 Liquid Yield Option Notes due 2031
(Zero CouponSenior) ("Securities"):

ARTICLE I  DEFINITIONS AND INCORPORATION BY REFERENCE

Section 1.01  Definitions

"144A Global Security"means a permanent Global Security in the form of the Security attached hereto as Exhibit A-1, and
that is deposited with and registered in the name of the Depositary, representing Securities sold in reliance on Rule 144A under the Securities Act.

"Accrued Original Issue Discount"of any Security represents the accrued portion of the total Original Issue Discount. The total
discount is the excess of the Principal Amount at Maturity per Security over the Issue Price. Accrued Original Issue Discount will be calculated on a daily basis at the yield of the Securities, on a
semi-annual bond equivalent basis, using a 360-day year composed of twelve 30-day months, beginning on the Issue Date.

"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 Procedures"means, with respect to any transfer or transaction involving a Global Security or beneficial interest therein,
the rules and procedures of the Depositary for such Security, in each case to the extent applicable to such transaction and as in effect from time to time.

"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 other than a Saturday or a Sunday or other day on which banking institutions in The City of
New York are required or authorized to close.

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

"Cash"or"cash"means such coin or currency of The United States of America as at any
time of payment is legal tender for the payment of public and private debts.

"CAP-OID"means additional Original Issue Discount accruable in respect of Contingent Additional Principal.

"Certificated Securities"means Securities that are in the form of the Securities attached hereto as Exhibit A-2.

"Common Stock"shall mean the shares of Common Stock, $0.01 par value, of the Company as it exists on the date of this Indenture or any
other shares of Capital Stock of the Company into which the Common Stock shall be reclassified or changed.

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"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 any two Officers.

"Contingent Additional Principal"means such additional principal payable on the Securities, if any, as described in
Section 13.01.

"Contingent Cash Interest"shall mean such cash interest payable as described in Article 12.

"Corporate Trust Office"means the principal office of the Trustee at which at any time its corporate trust business shall be
administered, which office at the date hereof is located at 633 West 5th St., 12th Fl., Los Angeles, California 90071, Attention: Corporate Trust Administration (Chiron Corporation
Liquid Yield Option Notes due 2031) or such other address as the Trustee may designate from time to time by notice to the Company, or the principal corporate trust office of any successor Trustee (or
such other address as a successor Trustee may designate from time to time by notice to the Company).

"Debt"means with respect to the Company at any date, without duplication, obligations (other than nonrecourse obligations) for
borrowed money or evidenced by bonds, debentures, notes or similar instruments.

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

"Exchange Act"means the Exchange Act of 1934, as amended from time to time.

"Global Securities"means Securities that are in the form of the Securities attached hereto as Exhibit A-1, and to
the extent that such Securities are required to bear the Legend required by Section 2.06, such Securities will be in the form of a 144A Global Security.

"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, including the
provisions of the TIA that are deemed to be a part hereof.

"Institutional Accredited Investor Security"means a Security legended in the form attached hereto as Exhibit A-2,
representing Securities sold to Institutional Accredited Investors.

"Issue Date"of any Security means the date on which the Security was originally issued or deemed issued as set forth on the face of
the Security.

"Issue Price"of any Security means, in connection with the original issuance of such Security, the initial issue price at which the
Security is sold as set forth on the face of the Security.

"Officer"means the Chairman of the Board, the Vice Chairman, the Chief Executive Officer, the President, the Chief Financial Officer,
any Executive Vice 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 14.04 and 14.05, signed in the
name of the Company by any two Officers, and delivered to the Trustee. An Officers' Certificate given pursuant to Section 4.03 shall be signed by the principal executive

2

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financial or accounting Officer of the Company but need not contain the information specified in Sections 14.04 and 14.05.

"Opinion of Counsel"means a written opinion containing the information specified in Sections 14.04 and 14.05, from legal counsel who
is acceptable to the Trustee. The counsel may be an employee of, or counsel to, the Company or the Trustee.

"Original Issue Discount"of any Security means the difference between the Issue Price and the Principal Amount at Maturity of the
Security as set forth on the face of the Security.

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

"Principal Amount at Maturity"of a Security means the principal amount at maturity as set forth on the face of the Security.

"Redemption Date"or"redemption date"means the date specified for redemption of the
Securities in accordance with the terms of the Securities and this Indenture.

"Redemption Price"or"redemption price"shall have the meaning set forth in
paragraph 6 of the Securities.

"Responsible Officer"means, when used with respect to the Trustee, any officer within the corporate trust department of the Trustee,
including any vice president, assistant vice president, assistant secretary, trust officer or any other officer of the Trustee who customarily performs functions similar to those performed by the
Persons who at the time shall be such officers, respectively, or to whom any corporate trust matter is referred because of such person's knowledge of and familiarity with the particular subject and
who, in each case, shall have direct responsibility for the administration of this Indenture.

"Restricted Security"means a Security required to bear the restrictive Legend set forth in the form of Securities set forth in
Exhibit A-1 and A-2 of this Indenture.

"Rule 144A"means Rule 144A under the Securities Act (or any successor provision), as it may be amended from time to
time.

"Sale Price"of Capital Stock on any date means the closing per share sale price (or, if no closing sale price is reported, the average
of the bid and ask prices or, if more than one in either case, the average of the average bid and the average ask prices) on such date as reported in the composite transactions for the principal
United States securities exchange on which the Capital Stock is traded or, if the Capital Stock is not listed on a United States national or regional securities exchange, as reported by the National
Association of Securities Dealers Automated Quotation System or by the National Quotation Bureau Incorporated. In the absence of such quotation, the Company shall be entitled to determine the Sale
Price on the basis of such quotations as it considers appropriate.

"SEC"means the Securities and Exchange Commission.

"Securities"means any of the Company's Liquid Yield Option Notes due 2031 (Zero Coupon-Senior), as amended or
supplemented from time to time, issued under this Indenture.

"Securities Act"means the Securities Act of 1933, as amended from time to time.

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

"Special Record Date"means for the payment of any Defaulted Interest, the date fixed by the Trustee pursuant to Section 11.02.

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"Stated Maturity",when used with respect to any Security, means the date specified in such Security as the fixed date on which an
amount equal to the Principal Amount at Maturity and any Contingent Additional Principal (and CAP-OID) thereon, if any, of such Security is due and payable.

"Significant Subsidiary",as such term is defined in Rule 1-02 of Regulation S-X under the
Securities Act.

"Subsidiary"means (i) a corporation, a majority of whose Capital Stock with voting power, under ordinary circumstances, to
elect directors is, at the date of determination, directly or indirectly owned by the Company, by one or more Subsidiaries of the Company or by the Company and one or more Subsidiaries of the Company,
(ii) a partnership in which the Company or a Subsidiary of the Company holds a majority interest in the equity capital or profits of such partnership, or (iii) any other person (other
than a corporation or a partnership) in which the Company, a Subsidiary of the Company or the Company and one or more Subsidiaries of the Company, directly or indirectly, at the date of determination,
has (x) at least a majority ownership interest or (y) the power to elect or direct the election of a majority of the directors or other governing body of such person.

"TIA"means the Trust Indenture Act of 1939 as in effect on the date of this Indenture, provided, however, that in the event the TIA is
amended after such date, TIA means, to the extent required by any such amendment, the TIA as so amended.

"trading day"means a day during which trading in securities generally occurs on the New York Stock Exchange or, if the Common Stock is
not listed on the New York Stock Exchange, on the principal other national or regional securities exchange on which the Common Stock is then listed or, if the Common Stock is not listed on a national
or regional securities exchange, on the National Association of Securities Dealers Automated Quotation System or, if the Common Stock is not quoted on the
National Association of Securities Dealers Automated Quotation System, on the principal other market on which the Common Stock is then traded.

"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.

Section 1.02  Other Definitions.

|Term                                    |  | Defined in
Section
|--------------------------------------- |  | ------------------
|"Act"                                   |  | 1.05(a)           
|"Agent Members"                         |  | 2.12(e)           
|"Associate"                             |  | 3.08(a)           
|"Average Sale Price"                    |  | 10.01             
|"Bankruptcy Law"                        |  | 6.01              
|"beneficial owner"                      |  | 3.08(a)           
|"Bid Solicitation Agent"                |  | 2.03              
|"Change in Control"                     |  | 3.08(a)           
|"Change in Control Purchase Date"       |  | 3.08(a)           
|"Change in Control Purchase Notice"     |  | 3.08(c)           
|"Change in Control Purchase Price"      |  | 3.08(a)           
|"Common Stock Record Date"              |  | 12.01             
|"Company Notice"                        |  | 3.07(e)           
|"Company Notice Date"                   |  | 3.07(c)           
|"Contingent Cash Interest Payment Date" |  | 12.02             
|"Contingent Cash Interest Record Date"  |  | 12.02             

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|"Conversion Agent"                    |  | 2.03    
|------------------------------------- |  | --------
|"Conversion Date"                     |  | 10.02   
|"Conversion Rate"                     |  | 10.01   
|"Custodian"                           |  | 6.01    
|"Defaulted Interest"                  |  | 11.02   
|"Depositary"                          |  | 2.01(a) 
|"DTC"                                 |  | 2.01(a) 
|"Event of Default"                    |  | 6.01    
|"Ex-Dividend Date"                    |  | 10.08(b)
|"Ex-Dividend Time"                    |  | 10.01   
|"Extraordinary Cash Dividend"         |  | 10.08(a)
|"Five-Trading-Day Measurement Period" |  | 12.01   
|"Institutional Accredited Investors"  |  | 2.01(b) 
|"Legal Holiday"                       |  | 14.09   
|"Legend"                              |  | 2.06(f) 
|"LYONs Market Price"                  |  | 12.01   
|"Market Price"                        |  | 3.07(d) 
|"Measurement Period"                  |  | 10.08(a)
|"noncontingent bond method"           |  | 4.07    
|"Notice of Default"                   |  | 6.01    
|"Paying Agent"                        |  | 2.03    
|"Post-Distribution Price"             |  | 10.08(b)
|"Purchase Date"                       |  | 3.07(a) 
|"Purchase Notice"                     |  | 3.07(a) 
|"Purchase Price"                      |  | 3.07(a) 
|"QIBs"                                |  | 2.01(a) 
|"Rate Solicitation Agent"             |  | 2.03    
|"Registrar"                           |  | 2.03    
|"Relevant Cash Dividends"             |  | 10.08(a)
|"Relevant Value"                      |  | 12.01   
|"Rights"                              |  | 10.19   
|"Rights Agreement"                    |  | 10.19   
|"Rule 144A Information"               |  | 4.06    
|"Senior Debt Rate"                    |  | 13.01   
|"Stock Price Factor"                  |  | 13.01   
|"Time of Determination"               |  | 10.01   

Section 1.03Incorporation by Reference of Trust Indenture Act. 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.

5

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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 United States 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.

Section 1.05  Acts of Holders.

(a) Any
request, demand, authorization, direction, notice, consent, waiver or other action provided by this Indenture to be given or taken by Holders may be embodied in
and evidenced by one or more instruments (which may take the form of an electronic writing or messaging or otherwise be in accordance with customary procedures of the Depositary or the Trustee) of
substantially similar tenor signed by such Holders in person or by agent duly appointed in writing (which may be in electronic form); and, except as herein otherwise expressly provided, such action
shall become effective when such instrument or instruments are delivered to the Trustee and, where it is hereby expressly required, to the Company. Such instrument or instruments (and the action
embodied therein and evidenced thereby) are herein sometimes referred to as the "Act" of Holders signing such instrument or instruments. Proof of execution of any such instrument or of a writing
appointing any such agent (either of which may be
in electronic form) shall be sufficient for any purpose of this Indenture and conclusive in favor of the Trustee and the Company, if made in the manner provided in this Section.

(b) The
fact and date of the execution by any Person of any such instrument or writing may be proved by the affidavit of a witness of such execution (or electronic
delivery) or by a certificate of a notary public or other officer authorized by law to take acknowledgments of deeds, certifying that the individual signing or delivering such instrument or writing
acknowledged to such officer the execution (or electronic delivery) thereof. Where such execution is by a signer acting in a capacity other than such signer's individual capacity, such certificate or
affidavit shall also constitute sufficient proof of such signer's authority. The fact and date of the execution of any such instrument or writing (electronic or otherwise), or the authority of the
Person executing the same, may also be proved in any other manner which the Trustee deems sufficient.

(c) The
ownership of Securities shall be proved by the register maintained by the Registrar.

(d) Any
request, demand, authorization, direction, notice, consent, waiver or other Act of the Holder of any Security shall bind every future Holder of the same
Security and the holder of every Security issued upon the registration of transfer thereof or in exchange therefor or in lieu thereof in respect of anything done, omitted or suffered to be done by the
Trustee or the Company in reliance thereon, whether or not notation of such action is made upon such Security.

(e) If
the Company shall solicit from the Holders any request, demand, authorization, direction, notice, consent, waiver or other Act, the Company may, at its option,
by or pursuant to a resolution of the Board of Directors, fix in advance a record date for the determination of Holders entitled to give such request, demand, authorization, direction, notice,
consent, waiver or other Act, but the Company shall have no obligation to do so. If such a record date is fixed, such request, demand, authorization, direction, notice, consent, waiver or other Act
may be given before or after such record date, but only the Holders of record at the close of business on such record date shall be deemed to be Holders for the purposes of determining whether Holders
of the requisite proportion of outstanding

6

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Securities have authorized or agreed or consented to such request, demand, authorization, direction, notice, consent, waiver or other Act, and for that purpose the outstanding Securities shall be
computed as of such record date; provided that no such authorization, agreement or consent by the Holders on such record date shall be deemed effective unless it shall become effective pursuant to the
provisions of this Indenture not later than six months after the record date.

ARTICLE II  THE SECURITIES

Section 2.01  Form and Dating.The Securities and the Trustee's certificate of authentication
shall be substantially in the form of Exhibits A-1 and A-2, which form 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.

(a)144A Global Securities.Securities offered and sold within the United States to "qualified
institutional buyers" as defined in Rule 144A ("QIBs") in reliance on Rule 144A shall be issued, initially in the form of a 144A Global Security, which shall be deposited with the
Trustee at its Corporate Trust Office, as custodian for the Depositary and registered in the name of The Depository Trust Company ("DTC") or the nominee thereof (such depositary, or any successor
thereto, and any such nominee being hereinafter referred to as the "Depositary"), duly executed by the Company and authenticated by the Trustee as hereinafter provided. The aggregate Principal Amount
at Maturity of the 144A Global Securities may from time to time be increased or decreased by adjustments made on the records of the Trustee and the Depositary as hereinafter provided.

(b)Institutional Accredited Investor Securities.Except as provided in this Section 2.01, 2.06
or 2.12, owners of beneficial interests in Global Securities will not be entitled to receive physical delivery of Certificated Securities. Securities offered and sold within the United States to
institutional "accredited investors" as defined in Rule 501(a)(1), (2) (3) and (7) under the Securities Act ("Institutional Accredited Investors") shall be issued, initially, in
the form of an Institutional Accredited Investor Security, duly executed by the Company and authenticated by the Trustee as hereinafter provided.

(c)Global Securities in General.Each Global Security shall represent such of the outstanding Securities as shall be
specified therein and each shall provide that it shall represent the aggregate Principal Amount at Maturity of outstanding Securities from time to time endorsed thereon and that the aggregate
Principal Amount at Maturity of outstanding Securities represented thereby may from time to time be reduced or increased, as appropriate, to reflect exchanges, redemptions and conversions.

Any
adjustment of the aggregate Principal Amount at Maturity of a Global Security to reflect the amount of any increase or decrease in the Principal Amount at Maturity of outstanding
Securities represented thereby shall be made by the Trustee in accordance with instructions given by the Holder thereof as required by Section 2.12 hereof and shall be made on the records of
the Trustee and the Depositary.

(d)Book-Entry Provisions.This Section 2.01(d) shall apply only to Global Securities
deposited with or on behalf of the Depositary.

The
Company shall execute and the Trustee shall, in accordance with this Section 2.01(d), authenticate and deliver initially one or more Global Securities that (a) shall
be registered in the name

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of the Depositary, (b) shall be delivered by the Trustee to the Depositary or pursuant to the Depositary's instructions and (c) shall bear legends substantially to the following effect:



(e)Certificated Securities.Securities not issued as interests in the Global Securities will be issued
in certificated form substantially in the form of Exhibit A-2 attached hereto.

Section 2.02  Execution and Authentication.The Securities shall be executed on behalf of the
Company by any Officer. The signature of the Officer on the Securities may be manual or facsimile.

Securities
bearing the manual or facsimile signatures of an individual who was at the time of the execution of the Securities the proper Officer of the Company shall bind the Company,
notwithstanding
that such individual has ceased to hold such office prior to the authentication and delivery of such Securities or did not hold such office 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 at Maturity of up to $730,000,000 ($915,000,000 aggregate Principal Amount at
Maturity, if the over-allotment option granted to the initial purchaser of the Securities is exercised in full) upon a Company Order without any further action by the Company. The
aggregate Principal Amount at Maturity of Securities outstanding at any time may not exceed the amount set forth in the foregoing sentence, except as provided in Section 2.07 and
Article 13 hereof.

The
Securities shall be issued only in registered form without coupons and only in denominations of $1,000 of Principal Amount at Maturity and any integral multiple thereof.

Section 2.03  Registrar, Paying Agent, Conversion Agent, Bid Solicitation Agent and Rate Solicitation 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 Company shall also appoint a bid solicitation

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agent (the "Bid Solicitation Agent") to act pursuant to Section 12.03 hereof and paragraph 3 of the Securities and a rate solicitation agent ("Rate Solicitation Agent") to act pursuant
to Section 13.04 hereof and paragraph 5.B of the Securities. The Registrar shall keep a 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, including any named pursuant
to Section 4.05. The term Conversion Agent includes any additional conversion agent, including any named pursuant to Section 4.05.

The
Company shall enter into an appropriate agency agreement with any Registrar or co-registrar, Paying Agent, Conversion Agent, Bid Solicitation Agent or Rate
Solicitation Agent (other than 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, Conversion Agent, Rate Solicitation Agent, or Bid Solicitation 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. None of the Company
or any Subsidiary or any Affiliate of any of them may act as Bid Solicitation Agent or Rate Solicitation Agent.

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

Section 2.04  Paying Agent to Hold Money and Securities in Trust.Except as otherwise provided
herein, not later than 10:00 a.m., New York City time, on each due date of payments in respect of any Security, the Company shall deposit with the Paying Agent a sum of money (in immediately
available funds if deposited on the due date) or Common Stock 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 Common Stock 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 Common Stock 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 Common Stock 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 Common Stock held by it to
the Trustee and to account for any funds and Common Stock disbursed by it. Upon doing so, the Paying Agent shall have no further liability for the money or Common Stock.

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 semi-annually on June 1 and December 1 a listing of securityholders 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  Transfer and Exchange.Subject to Section 2.12 hereof,

(a) Upon
surrender for registration of transfer of any Security, together with a written instrument of transfer satisfactory to the Registrar duly executed by the
Securityholder or such Securityholder's attorney duly authorized in writing, at the office or agency of the Company designated as Registrar or co-registrar pursuant to Section 2.03,
the Company shall execute, and the Trustee upon receipt of a Company Order shall authenticate and deliver, in the name of the designated transferee or transferees, one or more new Securities of any
authorized denomination or denominations, of a like

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aggregate Principal Amount at Maturity. The Company shall not charge a service charge for any registration of transfer or exchange, but the Company may require payment of a sum sufficient to pay all
taxes, assessments or other governmental charges that may be imposed in connection with the registration of transfer or exchange of the Securities from the Securityholder requesting such registration
of transfer or exchange.

At
the option of the Holder, Certificated Securities may be exchanged for other Securities of any authorized denomination or denominations, of a like aggregate Principal Amount at
Maturity, upon surrender of the Securities to be exchanged, together with a written instrument of transfer satisfactory to the Registrar duly executed by the Securityholder or such Securityholder's
attorney duly authorized in writing, at such office or agency. Whenever any Securities are so surrendered for exchange, the Company shall execute, and the Trustee upon receipt of a Company Order shall
authenticate and deliver, the Securities which the Holder making the exchange is entitled to receive.

The
Company shall not be required to make, and the Registrar need not register, transfers or exchanges of Securities selected for redemption (except, in the case of Securities to be
redeemed in part, the portion thereof not to be redeemed) or any Securities in respect of which a Purchase Notice or Change in Control Purchase Notice has been given and not withdrawn by the Holder
thereof in accordance with the terms of this Indenture (except, in the case of Securities to be purchased in part, the portion thereof not to be purchased) or any Securities for a period of
15 days before the mailing of a notice of redemption of Securities to be redeemed.

(b) Notwithstanding
any provision to the contrary herein, so long as a Global Security remains outstanding and is held by or on behalf of the Depositary, transfers of a
Global Security, in whole or in part, shall be made only in accordance with Section 2.12 and this Section 2.06(b). Transfers of a Global Security shall be limited to transfers of such
Global Security in whole, or in part, to nominees of the Depositary or to a successor of the Depositary or such successor's nominee.

(c) Successive
registrations and registrations of transfers and exchanges as aforesaid may be made from time to time as desired, and each such registration shall be
noted on the register for the Securities.

(d) Any
Registrar appointed pursuant to Section 2.03 hereof shall provide to the Trustee such information as the Trustee may reasonably require in connection
with the delivery by such Registrar of Securities upon registration of transfer or exchange of Securities.

(e) No
Registrar shall be required to make registrations of transfer or exchange of Securities during any periods designated in the text of the Securities or in this
Indenture as periods during which such registration of transfers and exchanges need not be made.

(f)  If
Securities are issued upon the registration of transfer, exchange or replacement of Securities subject to restrictions on transfer and bearing the legends set
forth on the form of Security attached hereto as Exhibits A-1 and A-2 setting forth such restrictions (collectively, the "Legend"), or if a request is made to remove the Legend
on a Security, the Securities so issued shall bear the Legend, or the Legend shall not be removed, as the case may be, unless there is delivered to the Company and the Registrar such satisfactory
evidence, which shall include an Opinion of Counsel, as may be reasonably required by the Company and the Registrar, that neither the Legend nor the restrictions on transfer set forth therein are
required to ensure that transfers thereof comply with the provisions of Rule 144A or Rule 144 under the Securities Act or that such Securities are not "restricted" within the meaning of
Rule 144 under the Securities Act. Upon (i) provision of such satisfactory evidence, or (ii) notification by the Company to the Trustee and Registrar of the sale of such Security
pursuant to a registration statement that is effective at the time of such sale, the Trustee, at the written direction of the Company, shall authenticate and deliver a Security that does not bear the
Legend. If the Legend is

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removed from the face of a Security and the Security is subsequently held by an Affiliate of the Company, the Company shall use its reasonable best efforts to reinstate the Legend.

The
Trustee and the Registrar shall have no obligation or duty to monitor, determine or inquire as to compliance with any restrictions on transfer imposed under this Indenture or
under applicable law with respect to any transfer of any interest in any Security (including any transfers between or among Depositary participants or beneficial owners of interests in any Global
Security) other than to require delivery of such certificates and other documentation or evidence as are expressly required by, and to do so if and when expressly required by the terms of, this
Indenture, and to examine the same to determine substantial compliance as to form with the express requirements hereof.

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 at Maturity, 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 purchased by the Company pursuant to
Article 3 hereof, the Company in its discretion may, instead of issuing a new Security, pay or purchase 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 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 cancelled by it, those paid pursuant to Section 2.07 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 at Maturity 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 a Responsible Officer of the Trustee actually 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).

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If a Security is replaced pursuant to Section 2.07, the replaced Security ceases to be outstanding unless the Trustee and the Company receive proof satisfactory to each of them
that the replaced Security is held by a bona fide purchaser unaware that such Security has been replaced.

If
the Paying Agent holds, in accordance with this Indenture, on a Redemption Date, or on the Business Day following the Purchase Date or a Change in Control Purchase Date, or on
Stated Maturity, money or securities, if permitted hereunder, sufficient to pay Securities payable on that date, then immediately after such Redemption Date, Purchase Date, Change in Control Purchase
Date or Stated Maturity, as the case may be, such Securities shall cease to be outstanding and Original Issue Discount (and CAP-OID, if any), Contingent Cash Interest and Contingent
Additional Principal, if applicable, 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.

If
a Security is converted in accordance with Article 10, then from and after the time of conversion on the Conversion Date, such Security shall cease to be outstanding and
Original Issue Discount (and CAP-OID, if any), Contingent Cash Interest, if any, and Contingent Additional Principal, if any, shall cease to accrue on such Security.

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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 upon Company Order the Trustee shall
authenticate and deliver in exchange therefor a like Principal Amount at Maturity 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.

Section 2.10  Cancellation.All Securities surrendered for payment, purchase by the Company
pursuant to Article 3, 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 cancelled 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 cancelled 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 cancelled as provided in this
Section, except as expressly permitted by this Indenture. All cancelled Securities held by the Trustee shall be disposed of by the Trustee in accordance with the Trustee's customary procedure.

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 of the Security or the payment of any Redemption Price, Purchase Price or Change in Control Purchase Price, Contingent Cash Interest, if any, and Contingent Additional Principal,
if any, for the purpose of conversion and for all other purposes whatsoever, whether or not such Security be overdue, and neither the Company, the Trustee nor any agent of the Company or the Trustee
shall be affected by notice to the contrary.

Section 2.12  Global Securities.

(a) Notwithstanding
any other provisions of this Indenture or the Securities, (A) transfers of a Global Security, in whole or in part, shall be made only in
accordance with Section 2.06 and Section 2.12(a)(i), (B) transfer of a beneficial interest in a Global Security for a Certificated Security shall comply with Section 2.06
and Section 2.12(a)(ii) below, and (C) transfers of a Certificated Security shall comply with Section 2.06 and Section 2.12(a)(iii) and (iv) below.



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then
the Trustee shall cause, or direct the Registrar to cause, in accordance with the standing instructions and procedures existing between the Depositary and the Registrar, the
aggregate Principal Amount at Maturity of Securities represented by the Global Security to be decreased by the aggregate Principal Amount at Maturity of the Certificated Security to be issued, shall
authenticate and deliver such Certificated Security and shall debit or cause to be debited to the account of the Person specified in such instructions a beneficial interest in the Global Security
equal to the Principal Amount at Maturity of the Certificated Security so issued.





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(b) Subject
to the succeeding paragraph, every Security shall be subject to the restrictions on transfer provided in the Legend including the delivery of an Opinion of
Counsel, if so provided. Whenever any Restricted Security is presented or surrendered for registration of transfer or for exchange for a Security registered in a name other than that of the Holder,
such Security must be accompanied by a certificate in substantially the form set forth in Exhibit B-1, dated the date of such surrender and signed by the Holder of such Security, as
to compliance with such restrictions on transfer. The Registrar shall
not be required to accept for such registration of transfer or exchange any Security not so accompanied by a properly completed certificate.

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(c) The restrictions imposed by the Legend upon the transferability of any Security shall cease and terminate when such Security has been sold pursuant to an effective
registration statement under the Securities Act or transferred in compliance with Rule 144 under the Securities Act (or any successor provision thereto) or, if earlier, upon the expiration of
the holding period applicable to sales thereof under Rule 144(k) under the Securities Act (or any successor provision). Any Security as to which such restrictions on transfer shall have expired
in accordance with their terms or shall have terminated may, upon a surrender of such Security for exchange to the Registrar in accordance with the provisions of this Section 2.12 (accompanied,
in the event that such restrictions on transfer have terminated by reason of a transfer in compliance with Rule 144 or any successor provision, by an Opinion of Counsel from legal counsel
having substantial experience in practice under the Securities Act and otherwise reasonably acceptable to the Company, addressed to the Company, the Trustee and the Registrar and in form acceptable to
the Company, to the effect that the transfer of such Security has been made in compliance with Rule 144 or such successor provision), be exchanged for a new Security, of like tenor and
aggregate Principal Amount at Maturity, which shall not bear the restrictive Legend. The Company shall inform the Trustee of the effective date of any registration statement registering the Securities
under the Securities Act. The Trustee and the Registrar shall not be liable for any action taken or omitted to be taken by it in good faith in accordance with the aforementioned Opinion of Counsel or
registration statement.

(d) As
used in the preceding two paragraphs of this Section 2.12, the term "transfer" encompasses any sale, pledge, transfer, hypothecation or other disposition
of any Security.

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



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Section 2.13  CUSIP Numbers.The Company in issuing the Securities may use "CUSIP" numbers (if
then generally in use), and, if so, the Trustee shall use "CUSIP" numbers in notices of redemption as a convenience to Holders; provided that any such notice may state that no representation is made
as to the correctness of such numbers either as printed on the Securities or as contained in any notice of a redemption and that reliance may be placed only on the other identification numbers printed
on the
Securities, and any such redemption shall not be affected by any defect in or omission of such numbers. The Company will promptly notify the Trustee of any change in the CUSIP numbers.

ARTICLE III  REDEMPTION AND PURCHASES

Section 3.01  Right to Redeem; Notices to Trustee.The Company, at its option, may at any time on
or after June 12, 2006 redeem the Securities in accordance with the provisions of paragraphs 6 and 8 of the Securities. If the Company elects to redeem Securities pursuant to paragraph 6
of the Securities, it shall notify the Trustee in writing of the Redemption Date, the Principal Amount at Maturity of Securities to be redeemed and the Redemption Price.

The
Company shall give the notice to the Trustee provided for in this Section 3.01 by a Company Order, at least 35 days before the Redemption Date (unless a shorter
notice shall be satisfactory to the Trustee).

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 any other method the Trustee considers fair and appropriate (so long as such method is not prohibited by the
rules of any stock exchange or quotation system on which the Securities are then listed or quoted). The Trustee shall make the selection at least 30 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 at Maturity of Securities that have
denominations larger than $1,000.

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Securities and portions of them the Trustee selects shall be in Principal Amounts at Maturity of $1,000 or an integral 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:

(1) the
Redemption Date;

(2) the
Redemption Price;

(3) the
Conversion Rate;

(4) the
name and address of the Paying Agent and Conversion Agent;

(5) that
Securities called for redemption may be converted at any time before the close of business on the second Business Day immediately preceding the Redemption
Date;

(6) that
Holders who want to convert Securities must satisfy the requirements set forth in paragraph 9 of the Securities;

(7) that
Securities called for redemption must be surrendered to the Paying Agent to collect the Redemption Price;

(8) if
fewer than all the outstanding Securities are to be redeemed, the certificate number and Principal Amounts at Maturity of the particular Securities to be
redeemed;

(9) that,
unless the Company defaults in making payment of such Redemption Price on Securities called for redemption, Original Issue Discount (and CAP-OID,
if any), Contingent Cash Interest, if any, and Contingent Additional Principal, if any, on Securities called for redemption will cease to accrue on and after the Redemption Date;

(10) the
CUSIP number of the Securities; and

(11) any
other information the Company wants to present.

At
the Company's request, the Trustee shall give the notice of redemption to Holders in the Company's name and at the Company's expense, provided that the Company
makes such request at least five Business Days (unless a shorter period shall be satisfactory to the Trustee) prior to the date such notice of redemption must be mailed.

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 stated in the notice except for Securities which are converted in accordance with the terms of this
Indenture. Upon surrender to the Paying Agent, such Securities shall be paid at the Redemption Price stated in the notice.

Section 3.05  Deposit of Redemption Price.Prior to 10:00 a.m. (New York City time), on
the Redemption Date, the Company shall deposit with the Paying Agent (or if the Company or a

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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 for all Securities to be redeemed on that date other
than Securities or portions of Securities called for redemption which on or prior thereto have been delivered by the Company to the Trustee for cancellation or have been converted. The Paying Agent
shall as promptly as practicable return to the Company any money not required for that purpose because of conversion of Securities pursuant to Article 10. 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 at Maturity to the unredeemed portion of
the Security surrendered.

Section 3.07  Purchase of Securities at Option of the Holder.

(a)General.Securities shall be purchased by the Company, at the option of the Holder thereof, pursuant
to paragraph 7 of the Securities as of June 12, 2004, June 12, 2006, June 12, 2011, June 12, 2016, June 12, 2021 and June 12, 2026 (each, a "Purchase
Date"), at the purchase prices of $584.31, $608.04, $671.65, $741.92, $819.54 and $905.29, respectively, per $1,000 of Principal Amount at Maturity plus, if applicable, Contingent Additional Principal
accrued (and CAP-OID) thereon (each, a "Purchase Price"), upon:





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If
a Holder, in such Holder's Purchase Notice and in any written notice of withdrawal delivered by such Holder pursuant to the terms of Section 3.09, fails to indicate such
Holder's choice with respect to the election set forth in clause (D) of Section 3.07(a)(1), such Holder shall be deemed to have elected to receive cash in respect of the Purchase Price
for all Securities subject to such Purchase Notice in the circumstances set forth in such clause (D).

The
Company shall purchase from the Holder thereof, pursuant to this Section 3.07, a portion of a Security if the Principal Amount at Maturity of such portion is $1,000 or an
integral multiple of $1,000. Provisions of this Indenture that apply to the purchase of all of a Security also apply to the purchase of such portion of such Security.

Any
purchase by the Company contemplated pursuant to the provisions of this Section 3.07 shall be consummated by the delivery of the consideration to be received by the Holder
promptly following the later of the Purchase Date and the time of delivery of the Security.

Notwithstanding
anything herein to the contrary, any Holder delivering to the Paying Agent the Purchase Notice contemplated by this Section 3.07(a) shall have the right to
withdraw such Purchase Notice at any time prior to the close of business on the Purchase Date by delivery of a written notice of withdrawal to the Paying Agent in accordance with Section 3.09.

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

(b)Company's Right to Elect Manner of Payment of Purchase Price.The Securities to be purchased
pursuant to Section 3.07(a) may be paid for, at the election of the Company, in cash or Common Stock, or in any combination of cash and Common Stock, subject to the conditions set forth in
Sections 3.07(c) and (d). The Company shall designate, in the Company Notice delivered pursuant to Section 3.07(e), whether the Company will purchase the Securities for cash or Common Stock,
or, if a combination thereof, the percentages or amounts of the Purchase Price of Securities in respect of which it will pay in cash or Common Stock; provided that the Company will pay cash for
fractional interests in Common Stock. For purposes of determining the existence of potential fractional interests, all Securities subject to purchase by the Company held by a Holder shall be
considered together (no matter how many separate certificates are to be presented). Each Holder whose Securities are purchased pursuant to this Section 3.07 shall receive the same percentage of
cash or Common Stock in payment of the Purchase Price for such Securities, except (i) as provided in Section 3.07(d) with regard to the payment of cash in lieu of fractional shares of
Common Stock and (ii) in the event that the Company is unable to purchase the Securities of a Holder or Holders for Common Stock because any necessary qualifications or registrations of the
Common Stock under applicable state securities laws cannot be obtained, the Company may purchase the Securities of such Holder or Holders for cash. The
Company may not change its election with respect to the consideration (or components or percentages of components thereof) to be paid once the Company has given its Company Notice to Securityholders
except pursuant to this Section 3.07(b) or pursuant to Section 3.07(d) in the event of a failure to satisfy, prior to the close of business on the Purchase Date, any condition to the
payment of the Purchase Price, in whole or in part, in Common Stock.

At
least three Business Days before the Company Notice Date, the Company shall deliver an Officers' Certificate to the Trustee specifying:



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(c)Purchase with Cash.On each Purchase Date, at the option of the Company, the Purchase Price of
Securities in respect of which a Purchase Notice pursuant to Section 3.07(a) has been given, or a specified percentage thereof, may be paid by the Company with cash equal to the aggregate
Purchase Price of such Securities. If the Company elects to purchase Securities with cash, the Company Notice, as provided in Section 3.07(e), shall be sent to Holders (and to beneficial owners
as required by applicable law) not less than 20 Business Days prior to such Purchase Date (the "Company Notice Date").

(d)Payment by Issuance of Common Stock.On each Purchase Date, at the option of the Company, the
Purchase Price of Securities in respect of which a Purchase Notice pursuant to Section 3.07(a) has been given, or a specified percentage thereof, may be paid by the Company by the issuance of a
number of shares of Common Stock equal to the quotient obtained by dividing (i) the amount of cash to which the Securityholders would have been entitled had the Company elected to pay all or
such specified percentage, as the case may be, of the Purchase Price of such Securities in cash by (ii) the Market Price of a share of Common Stock, subject to the next succeeding paragraph. If
the Company elects to
purchase Securities with Common Stock, the Company Notice, as provided in Section 3.07(e), shall be sent to Holders (and to beneficial owners as required by applicable law) on the Company
Notice Date.

The
Company will not issue a fractional share of Common Stock in payment of the Purchase Price. Instead the Company will pay cash for the current market value of the fractional share.
The current market value of a fraction of a share shall be determined by multiplying the Market Price by such fraction and rounding the product to the nearest whole cent. It is understood that if a
Holder elects to have more than one Security purchased, the number of shares of Common Stock shall be based on the aggregate amount of Securities to be purchased.

Upon
a payment by Common Stock pursuant to the terms hereof, that portion of accrued Original Issue Discount (and CAP-OID, if any), accrued Contingent Additional
Principal, if any, and accrued but unpaid Contingent Cash Interest, if any, attributable to the period from the Issue Date to the Purchase Date with respect to the purchased Security shall not be
cancelled, extinguished or forfeited but rather shall be deemed paid in full to the Holder through the delivery of the Common Stock in exchange for the Security being purchased pursuant to the terms
hereof, and the fair market value of such Common Stock (together with any cash payments in lieu of fractional shares of Common Stock) shall be treated as issued, to the extent thereof, first in
exchange for the accrued Original Issue Discount (and accrued CAP-OID, if any), Contingent Cash Interest, if any, and accrued Contingent Additional Principal, if any, through, but not
including, the Purchase Date, and the balance, if any, of the fair market value of such shares of Common Stock shall be treated as issued in exchange for the Issue Price of the Security being
purchased pursuant to the provisions hereof.

If
the Company elects to purchase the Securities by the issuance of shares of Common Stock, the Company Notice, as provided in Section 3.07(e), shall be sent to the Holders
(and to beneficial owners as required by applicable law) not later than the Company Notice Date.

The
Company's right to exercise its election to purchase the Securities pursuant to Section 3.07 through the issuance of shares of Common Stock shall be conditioned upon:



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Such
Officers' Certificate shall also set forth the number of shares of Common Stock to be issued for each $1,000 Principal Amount at Maturity of Securities and the Sale Price of a
share of Common Stock on each trading day during the period for which the Market Price is calculated. The Company may pay the Purchase Price (or any portion thereof) in Common Stock only if the
information necessary to calculate the Market Price is published in a daily newspaper of national circulation. If the foregoing conditions are not satisfied with respect to a Holder or Holders prior
to the close of business on the Purchase Date and the Company has elected to purchase the Securities pursuant to this Section 3.07 through the issuance of shares of Common Stock, the Company
shall pay the entire Purchase Price of the Securities of such Holder or Holders in cash.

The
"Market Price" of the Common Stock means the average of the Sale Prices of the Common Stock for the five trading day period ending on the third Business Day (if the third Business
Day prior to the applicable Purchase Date is a trading day or, if not, then on the last trading day) prior to the applicable Purchase Date, appropriately adjusted to take into account the occurrence,
during the period commencing on the first of such trading days during such five trading day period and ending on such Purchase Date, of any event described in Section 10.06, 10.07 or 10.08;
subject, however, to the conditions set forth in Sections 10.09 and 10.10.

(e)Notice of Election.The Company's notice of election to purchase with cash or Common Stock or any
combination thereof shall be sent to the Holders (and to beneficial owners as required by applicable law) in the manner provided in Section 14.02 at the time specified in Section 3.07(c)
or (d), as applicable
(the "Company Notice"). Such Company Notice shall state the manner of payment elected and shall contain the following information:

In
the event the Company has elected to pay the Purchase Price (or a specified percentage thereof) with Common Stock, the Company Notice shall:



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In
any case, each Company Notice shall include a form of Purchase Notice to be completed by a Securityholder and shall state:



At
the Company's request, the Trustee shall give such Company Notice in the Company's name and at the Company's expense; provided, however, that, in all cases, the text of such
Company Notice shall be prepared by the Company.

Upon
determination of the actual number of shares of Common Stock to be issued for each $1,000 Principal Amount at Maturity of Securities, the Company will issue a press release and
publish such determination on the Company's web site or otherwise publicly by another reasonable method.

(f)Covenants of the Company.All shares of Common Stock delivered upon purchase of the Securities
shall be newly issued shares or treasury shares, shall be duly authorized, validly issued, fully paid and nonassessable and shall be free from preemptive rights and free of any lien or adverse claim
created by the Company.

(g)Procedure upon Purchase.The Company shall deposit cash (in respect of a cash purchase under
Section 3.07(c) or for fractional interests, as applicable) or shares of Common Stock, or a combination thereof, as applicable, at the time and in the manner as provided in Section 3.11,
sufficient to pay the
aggregate Purchase Price of, all Securities to be purchased pursuant to this Section 3.07. As soon as practicable after the Purchase Date, the Company shall deliver to each Holder entitled to
receive Common Stock through the Paying Agent, a certificate for the number of full shares of Common Stock issuable in payment of the Purchase Price and cash in lieu of any fractional interests.

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The person in whose name the certificate for Common Stock is registered shall be treated as a holder of record of shares of Common Stock on the Business Day following the Purchase Date. Subject to
Section 3.07(d), no payment or adjustment will be made for dividends on the Common Stock the record date for which occurred on or prior to the Purchase Date.

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

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Section 3.08  Purchase of Securities at Option of the Holder upon Change in Control.

(a) If
on or prior to June 12, 2006 there shall have occurred a Change in Control, Securities shall be purchased by the Company, at the option of the Holder
thereof, at a purchase price specified in paragraph 7 of the Securities (the "Change in Control Purchase Price"), as of the date that is no later than 35 Business Days after the occurrence of
the Change in Control but in no event prior to the date on which such Change in Control occurs (the "Change in Control Purchase Date"), subject to satisfaction by or on behalf of the Holder of the
requirements set forth in Section 3.08(c).

A
"Change in Control" shall be deemed to have occurred at such time as either of the following events shall occur:



Notwithstanding
the foregoing provisions of this Section 3.08, a Change in Control shall not be deemed to have occurred by virtue of the Company, any Subsidiary, any employee stock ownership
plan or any

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other employee benefit plan of the Company or any Subsidiary, or any person holding Common Stock for or pursuant to the terms of any such employee benefit plan, filing or becoming obligated to
file a report under or in response to Schedule 13D or Schedule TO (or any successor schedule, form or report) under the Exchange Act disclosing beneficial ownership by it of shares of
Common Stock, whether in excess of 50% or otherwise.

"Associate"
shall have the meaning ascribed to such term in Rule 12b-2 of the General Rules and Regulations under the Exchange Act, as in effect on the date hereof.

(b) Within
15 Business Days after a Change in Control, which notice may be delivered in anticipation of a Change in Control, the Company shall mail a written notice of
Change in Control by first-class mail to the Trustee and to each Holder (and to beneficial owners as required by applicable law). The notice shall include a form of Change in Control Purchase Notice
to be completed by the Securityholder and shall state:



(c) A
Holder may exercise its rights specified in Section 3.08(a) upon delivery of a written notice of purchase (a "Change in Control Purchase Notice") to the
Paying Agent at any time prior to the close of business on the Change in Control Purchase Date, stating:



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The
delivery of such Security to the Paying Agent prior to, on or after the Change in Control Purchase Date (together with all necessary endorsements) at the offices of the Paying
Agent shall be a condition to the receipt by the Holder of the Change in Control Purchase Price therefor; provided, however, that such Change in Control Purchase Price shall be so paid pursuant to
this Section 3.08 only if the Security so delivered to the Paying Agent shall conform in all respects to the description thereof set forth in the related Change in Control Purchase Notice.

The
Company shall purchase from the Holder thereof, pursuant to this Section 3.08, a portion of a Security if the Principal Amount at Maturity of such portion is $1,000 or an
integral multiple of $1,000. Provisions of this Indenture that apply to the purchase of all of a Security also apply to the purchase of such portion of such Security.

Any
purchase by the Company contemplated pursuant to the provisions of this Section 3.08 shall be consummated by the delivery of the consideration to be received by the Holder
promptly following the later of the Change in Control Purchase Date and the time of delivery of the Security to the Paying Agent in accordance with this Section 3.08.

Notwithstanding
anything herein to the contrary, any Holder delivering to the Paying Agent the Change in Control Purchase Notice contemplated by this Section 3.08(c) shall have
the right to withdraw such Change in Control Purchase Notice at any time prior to the close of business on the Change in Control Purchase Date by delivery of a written notice of withdrawal to the
Paying Agent in accordance with Section 3.09.

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

The
Company shall not be required to comply with this Section 3.08 if a third party mails a written notice of Change in Control in the manner, at the times and otherwise in
compliance with this Section 3.08 and repurchases all Securities for which a Change in Control Purchase Notice shall be delivered and not withdrawn.

Section 3.09  Effect of Purchase Notice or Change in Control Purchase Notice.Upon receipt by the
Paying Agent of the Purchase Notice or Change in Control Purchase Notice specified in Section 3.07(a) or Section 3.08(c), as applicable, the Holder of the Security in respect of which
such Purchase Notice or Change in Control Purchase Notice, as the case may be, was given shall (unless such Purchase Notice or Change in Control Purchase Notice is withdrawn as specified in the
following two paragraphs) thereafter be entitled to receive solely the Purchase Price or Change in Control Purchase Price, as the case may be. Such Purchase Price or Change in Control Purchase Price
shall be paid to such Holder, subject to receipts of funds and/or securities by the Paying Agent, promptly following the later of (x) the Purchase Date or the Change in Control Purchase Date,
as the case may be, with respect to such Security (provided the conditions in Section 3.07(a) or Section 3.08(c), as applicable, have been satisfied) and (y) the time of delivery
of such Security to the Paying Agent by the Holder thereof in the manner required by Section 3.07(a) or Section 3.08(c), as applicable. Securities in respect of which a Purchase Notice
or Change in Control Purchase Notice, as the case may be, has been given by the Holder thereof may not be converted pursuant to Article 10 hereof on or after the date of the delivery of such
Purchase Notice or Change in Control Purchase Notice, as the case may be, unless such Purchase Notice or Change in Control Purchase Notice, as the case may be, has first been validly withdrawn as
specified in the following two paragraphs.

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A Purchase Notice or Change in Control Purchase Notice, as the case may be, may be withdrawn by means of a written notice of withdrawal delivered to the office of the Paying Agent in
accordance with the Purchase Notice or Change in Control Purchase Notice, as the case may be, at any time prior to the close of business on the Purchase Date or the Change in Control Purchase Date, as
the case may be, specifying:



A
written notice of withdrawal of a Purchase Notice may be in the form set forth in the preceding paragraph or may be in the form of (i) a conditional withdrawal contained in a
Purchase Notice pursuant to the terms of Section 3.07(a)(1)(D) or (ii) a conditional withdrawal containing the information set forth in Section 3.07(a)(1)(D) and the preceding
paragraph and contained in a written notice of withdrawal delivered to the Paying Agent as set forth in the preceding paragraph.

There
shall be no purchase of any Securities pursuant to Section 3.07 (other than through the issuance of Common Stock in payment of the Purchase Price, including cash in lieu
of fractional shares) or 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 Purchase Notice or Change in Control
Purchase Notice, as the case may be) and is continuing an Event of Default (other than a default in the payment of the Purchase Price or Change in Control Purchase Price, as the case may be). The
Paying Agent will promptly return to the respective Holders thereof any Securities (x) with respect to which a Purchase Notice or Change in Control Purchase Notice, as the case may be, has been
withdrawn in compliance with this Indenture, or (y) held by it during the continuance of an Event of Default (other than a default in the payment of the Purchase Price or Change in Control
Purchase Price, as the case may be, with respect to the Securities in which case), upon such return, the Purchase Notice or Change in Control Purchase Notice with respect thereto shall be deemed to
have been withdrawn.

Section 3.10  Deposit of Purchase Price or Change in Control Purchase Price.Prior to
10:00 a.m., New York City time, on the Business Day following the Purchase Date or the Change in Control Purchase Date, as the case may be, 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 (in immediately available funds if deposited on such Business Day) or Common Stock, if permitted hereunder, sufficient to pay the aggregate Purchase Price or Change in Control Purchase Price, as
the case may be, of all the Securities or portions thereof which are to be purchased as of the Purchase Date or Change in Control Purchase Date, as the case may be.

Section 3.11  Securities Purchased in Part.Any Security which is to be purchased 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 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 at Maturity equal to, and in exchange for,
the portion of the Principal Amount at Maturity of the Security so surrendered which is not purchased.

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Section 3.12  Covenant to Comply With Securities Laws Upon Purchase of Securities.In connection
with any offer to purchase or purchase of Securities under Section 3.07 or 3.08 hereof (provided that such offer or purchase constitutes an "issuer tender offer" for purposes of
Rule 13e-4 (which term, as used herein, includes any successor provision thereto) under the Exchange Act at the time of such offer or purchase), the Company shall to the extent
applicable (i) comply with Rule 13e-4 and Rule 14e-1 under the Exchange Act, (ii) file the related Schedule TO (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 Sections 3.07 and 3.08 to be exercised in
the time and in the manner specified in Sections 3.07 and 3.08.

Section 3.13  Repayment to the Company.The Trustee and the Paying Agent shall promptly return to
the Company any cash or shares of Common Stock that remain unclaimed as provided in paragraph 15 of the Securities, together with interest or dividends, if any, thereon (subject to the
provisions of Section 7.01(f)), held by them for the payment of the Purchase Price or Change in Control Purchase Price, as the case may be; provided, however, that to the extent that the
aggregate amount of cash or shares of Common Stock deposited by the Company pursuant to Section 3.11 exceeds the aggregate Purchase Price or Change in Control Purchase Price, as the case may
be, of, the Securities or portions thereof which the Company is obligated to purchase as of the Purchase Date or Change in Control Purchase Date, as the case may be, whether as a result of withdrawal
or otherwise, then promptly after the Business Day following the Purchase Date or Change in Control Purchase Date, as the case may be, the Trustee shall return any such excess to the Company together
with interest or dividends, if any, thereon (subject to the provisions of Section 7.01(f)).

ARTICLE IV  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. Any amounts to be given to the Trustee or Paying Agent, shall be deposited with the Trustee or
Paying Agent by 10:00 a.m., New York City time, by the Company. Principal Amount at Maturity, Issue Price plus accrued Original Issue Discount (and CAP-OID, if any), Redemption
Price, Purchase Price, Change in Control Purchase Price, Contingent Cash Interest, if any, and Contingent Additional Principal, if any, shall be considered paid on the applicable date due if on such
date (or, in the case of a Purchase Price or Change in Control Purchase Price, on the Business Day following the applicable Purchase Date or Change in Control Purchase Date, as the case may be) the
Trustee or the Paying Agent holds, in accordance with this Indenture, money or securities, if permitted hereunder, sufficient to pay all such amounts then due.

The
Company shall, to the extent permitted by law, pay interest on overdue amounts at the rate per annum set forth in paragraph 1 of the Securities, compounded
semi-annually, which interest shall accrue from the date such overdue amount was originally 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. The accrual of such interest on overdue amounts shall be in lieu of, and not in addition to, the continued accrual of Original Issue
Discount (and CAP-OID, if any), Contingent Cash Interest, if any, and Contingent Additional Principal, if any.

Section 4.02  SEC and Other Reports.If requested by the Trustee, the Company shall deliver to
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. The Company shall send to the Trustee all reports required pursuant to the provisions of TIA Section 314(a). Delivery of such reports,
information and documents to the Trustee is for

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

Section 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 December 31, 2001) an Officers' Certificate, stating whether or not to the best
knowledge of the signers thereof the Company is in default in the performance and observance of any of the terms, provisions and conditions of this Indenture (without regard to any period of grace or
requirement of notice provided hereunder) and if the Company shall be in default, specifying all such defaults and the nature and status thereof of which they may have knowledge.

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 an office or agency of
the Trustee, Registrar, Paying Agent, Conversion Agent, Bid Solicitation Agent and Rate Solicitation Agent where Securities may be presented or surrendered for payment, where Securities may be
surrendered for registration of transfer, exchange, purchase, redemption or conversion and where notices and demands to or upon the Company in respect of the Securities and this Indenture may be
served. The office of State Street Bank and Trust Company of California, N.A., 633 West 5th St., 12th Fl., Los Angeles, California 90071, Attention: Corporate Trust Administration
(Chiron Corporation Liquid Yield Option Notes due 2031), shall initially be such office or agency for all of the aforesaid purposes.
The Company shall give prompt written notice to the Trustee of the location, and of any change in the location, of any such office or agency (other than a change in the location of the office of the
Trustee). If at any time the Company shall fail to maintain any such required office or agency or shall fail to furnish the Trustee with the address thereof, such presentations, surrenders, notices
and demands may be made or served at the address of the Trustee set forth in Section 14.02. The Company shall, in addition, maintain an office or agency of the Trustee, Registrar, Paying Agent,
Conversion Agent, Bid Solicitation Agent and Rate Solicitation Agent in the Borough of Manhattan, The City of New York for the purposes noted above.

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 obligations to maintain an office or agency in the
Borough of Manhattan, The City of New York for such purpose.

Section 4.06  Delivery of Certain Information.At any time when the Company is not subject to
Section 13 or 15(d) of the Exchange Act, upon the request of a Holder or any beneficial holder of Securities or shares of Common Stock which are restricted securities issued upon conversion
thereof, the Company will promptly furnish or cause to be furnished Rule 144A Information (as defined below) to such Holder or any beneficial holder of Securities or holder of shares of Common
Stock issued upon conversion of Securities, or to a prospective purchaser of any such security designated by any such holder, as the case may be, to the extent required to permit compliance by such
Holder or holder with Rule 144A under the Securities Act in connection with the resale of any such security. "Rule 144A Information" shall be such information as is specified pursuant to
Rule 144A(d)(4) under the Securities Act.

Section 4.07  Calculation of Original Issue Discount.The Company agrees, and each Holder and any
beneficial holder of a Security by its purchase thereof shall be deemed to agree, to treat, for

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United States federal income tax purposes, the Securities as debt instruments that are subject to Section 1.1275-4(b) of the Treasury Regulations. For United States federal income
tax purposes, the Company shall accrue interest with respect to outstanding Securities as original issue discount according to the "noncontingent bond method," set forth in
section 1.1275-4(b) of the Treasury Regulations, using a comparable yield of 6.37 percent compounded semi-annually and the projected payment schedule attached as
Exhibit C to this Indenture. The Company shall file with the Trustee promptly at the end of each calendar year (i) a written notice specifying the amount of original issue discount for
United States federal income tax purposes (including daily rates and accrual periods) accrued on outstanding Securities as of the end of such year and (ii) such other specific information
relating to such original issue discount as may then be relevant under the Internal Revenue Code of 1986, as amended from time to time, including the amount of any adjustment made under the
noncontingent bond method to account for the amount of any difference between the amount of an actual payment and the amount of a projected payment.

The Company acknowledges and agrees, and each Holder and any beneficial holder of a Security by its purchase thereof shall be deemed to acknowledge and agree,
that (i) the comparable yield and the schedule of projected payments are determined on the basis of an assumption of linear growth of the stock price and are not determined for any purpose
other than for the determination of interest accruals and adjustments thereof in respect of the Securities for United States federal income tax purposes and (ii) the comparable yield and the
schedule of projected payments do not constitute a projection or representation regarding the amounts payable on the Securities.

ARTICLE V  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 or convey, transfer or lease all or substantially all of its properties and assets to any person, unless:



For
purposes of the foregoing, the transfer (by lease, assignment, sale or otherwise) of the properties and assets of one or more Subsidiaries (other than to the Company or another
Subsidiary), which, if such assets were owned by the Company, would constitute all or substantially all of the properties and assets of the Company, shall be deemed to be the transfer of all or
substantially all of the properties and assets of the Company.

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The 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 a lease and any 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. Subject to Section 9.06, the Company, the Trustee and the successor person shall enter into a supplemental indenture to evidence the succession and
substitution of such successor person and such discharge and release of the Company.

ARTICLE VI  DEFAULTS AND REMEDIES

Section 6.01  Events of Default.An "Event of Default" means the occurrence of any one of the
following events:



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and
the order or decree remains unstayed and in effect for 60 days.

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

"Custodian"
means any receiver, trustee, assignee, liquidator, custodian or similar official under any Bankruptcy Law.

A
Default under clause (3) or clause (4) above is not an Event of Default until the Trustee notifies the Company, or the Holders of at least 25% in aggregate Principal
Amount at Maturity 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) or clause (4) above after actual receipt of such notice. Any such notice must specify the Default, demand that it be remedied and state that such notice is a
"Notice of Default".

The
Company shall deliver to the Trustee, within 30 days after it becomes aware of the occurrence thereof, written notice of any event which with the giving of notice or the
lapse of time, or both, would become an Event of Default under clause (3) or clause (4) above, its status and what action the Company is taking or proposes to take with respect thereto.

Section 6.02  Acceleration.If an Event of Default (other than an Event of Default specified in
Section 6.01(5) or (6) in respect of the Company) occurs and is continuing, the Trustee by Notice to the Company, or the Holders of at least 25% in aggregate Principal Amount at Maturity
of the Securities at the time outstanding by notice to the Company and the Trustee, may declare the Issue Price plus accrued Original Issue Discount (and CAP-OID, if any), accrued and
unpaid Contingent Cash Interest, if any, and Contingent Additional Principal, if any, through the date of such declaration, on all the Securities to be immediately due and payable. Upon such a
declaration, such Issue Price plus accrued Original Issue Discount (and CAP-OID, if any), accrued and unpaid Contingent Cash Interest, if any, and accrued Contingent Additional Principal,
if any, shall be due and payable immediately. If an Event of Default specified in Section 6.01(5) or (6) occurs in respect of the Company and is continuing, the Issue Price plus accrued
Original Issue Discount (and CAP-OID), accrued and unpaid Contingent Cash Interest, if any, and accrued Contingent Additional Principal, if any, on all the Securities 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 at Maturity 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 if all existing Events of Default have been cured or waived except
nonpayment of the Issue Price plus accrued Original Issue Discount (and CAP-OID, if any) and

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accrued Contingent Additional Principal, if any, plus accrued and unpaid Contingent Cash Interest that have 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 Issue Price plus accrued Original Issue Discount (and CAP-OID, if any), accrued and unpaid Contingent Cash Interest and Contingent
Additional Principal, if any, on the Securities 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.Subject to Section 6.02, the Holders of a majority
in aggregate Principal Amount at Maturity 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 (a) an Event of Default described in Section 6.01(1) or Section 6.01(2)(b), a Default in respect of a provision that under Section 9.02 cannot be
amended without the consent of each Securityholder affected or (c) a Default which 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. This Section 6.04 shall be in lieu of
Section 316(a)1(B) of the TIA and such Section 316(a)1(B) is hereby expressly excluded from this Indenture, as permitted by the TIA.

Section 6.05  Control by Majority.The Holders of a majority in aggregate Principal Amount at
Maturity 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. This Section 6.05 shall be in lieu of Section 316(a)1(A) of the TIA and such Section 316(a)1(A) is hereby expressly excluded from this Indenture, as permitted
by the TIA.

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



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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 at Maturity, Issue Price plus accrued Original Issue Discount (and CAP-OID, if any), Redemption Price,
Purchase Price, Change in Control Purchase Price, Contingent Cash Interest, if any, and accrued Contingent Additional Principal, if any, in respect of the Securities held by such Holder, on or after
the respective due dates expressed in the Securities or any Redemption Date, 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 such Holder.

Section 6.08  Collection Suit by Trustee.If an Event of Default described in
Section 6.01(1) or Section 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 at Maturity, Issue Price plus accrued Original Issue Discount (and
CAP-OID, if any), Redemption Price, Purchase Price, Change in Control Purchase Price, Contingent Cash Interest, if any, or Contingent Additional Principal, if any, 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 claim of any Holder in any such proceeding.

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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:

FIRST:
to the Trustee for amounts due under Section 7.07;

SECOND:
to Securityholders for amounts due and unpaid on the Securities for the Principal Amount at Maturity, Issue Price plus accrued Original Issue Discount (and
CAP-OID, if any), Redemption Price, Purchase Price, Change in Control Purchase Price, Contingent Cash Interest, if any, and accrued Contingent Additional Principal, if any, as the case may
be, ratably, without preference or priority of any kind, according to such amounts due and payable on the Securities; and

THIRD:
the balance, if any, to the Company.

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
Trustee shall mail to each Securityholder and the Company a notice that states the record date, the payment date and the amount to be paid.

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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 and expenses, 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 at Maturity of the Securities at the time outstanding. This Section 6.11 shall be in lieu of
Section 315(e) of the TIA and such Section 315(e) is hereby expressly excluded from this Indenture, as permitted by the TIA.

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 at Maturity, Issue Price plus accrued Original Issue Discount
(and CAP-OID, if any), Redemption Price, Purchase Price, Change in Control Purchase Price, Contingent Cash Interest, if any, and accrued Contingent Additional Principal, if any, in respect
of Securities, or any interest on such amounts, 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 law, 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 VII  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 person would exercise or use under the circumstances in the conduct of such person's own affairs.

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



This
Section 7.01(b) shall be in lieu of Section 315(a) of the TIA and such Section 315(a) is hereby expressly excluded from this Indenture, as permitted by the TIA.

(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:



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Subparagraphs
(c)(1), (2) and (3) shall be in lieu of Sections 315(d)(1), 315(d)(2) and 315(d)(3) of the TIA and such Sections 315(d)(1), 315(d)(2) and 315(d)(3) are hereby expressly
excluded from this Indenture, as permitted by the TIA.

(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. The Trustee (acting in any capacity
hereunder) shall be under no liability for interest on any money received by it hereunder unless otherwise agreed in writing with the Company.



Subject to its duties and responsibilities under the provisions of Section 7.01, and, except as expressly excluded from this Indenture pursuant to said
Section 7.01, under the TIA:

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

(b) whenever
in the administration of this Indenture the Trustee shall deem it desirable that a matter be proved or established prior to taking, suffering or omitting
any action hereunder, the Trustee (unless other evidence be herein specifically prescribed) may, in the absence of bad faith on its part, conclusively rely upon an Officers' Certificate;

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

(d) the
Trustee shall not be liable for any action taken, suffered, or omitted to be taken by it in good faith which it believes to be authorized or within its rights
or powers conferred under this Indenture;

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

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

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(g) any request or direction of the Company mentioned herein shall be sufficiently evidenced by a Company Request or Company Order and any resolution of the Board of
Directors may be sufficiently evidenced by a resolution of the Board of Directors;

(h) the
Trustee shall not be bound to make any investigation into the facts or matters stated in any resolution, certificate, statement, instrument, opinion, report,
notice, request, direction, consent, order, bond, debenture, note, other evidence of indebtedness or other paper or document, but the Trustee, in its discretion, may make such further inquiry or
investigation into such facts or matters as it may see fit, and, if the Trustee shall determine to make such further inquiry or investigation, it shall be entitled to examine the books, records and
premises of the Company, personally or by agent or attorney at the sole cost of the Company and shall incur no liability or additional liability of any kind by reason of such inquiry or investigation;

(i)  the
Trustee shall not be deemed to have notice of any Default or Event of Default unless a Responsible Officer of the Trustee has actual knowledge thereof or
unless written notice of any event which is in fact such a default is received by the Trustee at the Corporate Trust Office of the Trustee, and such notice references the Securities and this
Indenture;

(j)  the
rights, privileges, protections, immunities and benefits given to the Trustee, including, without limitation, its right to be indemnified, are extended to, and
shall be enforceable by, the Trustee in each of its capacities hereunder, and to each agent, custodian and other Person employed to act hereunder; and

(k) the
Trustee may request that the Company deliver an Officers' Certificate setting forth the names of individuals and/or titles of officers authorized at such time
to take specified actions pursuant to this Indenture, which Officers' Certificate may be signed by any person authorized to sign an Officers' Certificate, including any person specified as so
authorized in any such certificate previously delivered and not superseded.

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 like rights. However, the Trustee must comply with Sections 7.10 and 7.11.

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 or application of the proceeds from the Securities, it shall not be responsible for any statement in the registration
statement for the Securities under the Securities Act or in the Indenture or the Securities (other than its certificate of authentication), 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 if it is known to the Trustee, the Trustee shall give
to each Securityholder notice of the Default within 90 days after it occurs unless such Default shall have been cured or waived before the giving of such notice. 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 Responsible Officers in good faith determines that withholding the notice is in
the interests of Securityholders. The second sentence of this Section 7.05 shall be in lieu of the proviso to Section 315(b) of the TIA and such proviso is hereby expressly excluded from
this Indenture, as permitted by the TIA. The Trustee shall not be deemed to have knowledge of a Default unless a Responsible Officer of the Trustee has received written notice of such Default.

Section 7.06 Reports by Trustee to Holders.Within 60 days after each June 30 beginning with the
June 30 following the date of this Indenture, the Trustee shall mail to each Securityholder a brief

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report dated as of such June 30 that complies with TIA Section 313(a), if required by such Section 313(a). The Trustee also shall comply with TIA Section 313(b).

A
copy of each report at the time of its mailing to Securityholders shall be filed with the SEC and each securities exchange, if any, on which the Securities are listed. The Company
agrees to promptly notify the Trustee whenever the Securities become listed on any securities exchange and of any delisting thereof.

Section 7.07 Compensation and Indemnity.The Company agrees:

(a) to
pay to the Trustee from time to time such reasonable compensation as the Company and the Trustee shall from time to time agree in writing for all services
rendered by it hereunder (which compensation shall not be limited (to the extent permitted by law) by any provision of law in regard to the compensation of a trustee of an express trust);

(b) to
reimburse the Trustee upon its request for all reasonable expenses, disbursements and advances incurred or made by the Trustee in accordance with any provision
of this Indenture (including the reasonable compensation and the expenses, advances and disbursements of its agents and counsel), except any such expense, disbursement or advance as may be
attributable to its negligence or bad faith; and

(c) to
indemnify the Trustee or any predecessor, Trustee and their agents for, and to hold them harmless against, any loss, damage, claim, liability, cost or expense
(including reasonable attorney's fees and taxes (other than taxes based upon, measured by or determined by the income of the Trustee)) incurred without negligence or bad faith on its part, arising out
of or in connection with the acceptance or administration of this trust, including the reasonable costs and expenses of defending itself against any claim (whether asserted by the Company or any
Holder or any other Person) or liability in connection with the exercise or performance of any of its powers or duties hereunder.

To
secure the Company's payment obligations in this Section 7.07, the Holders shall have been deemed to have granted to the Trustee 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 at Maturity, Issue Price plus accrued Original Issue Discount (and CAP-OID, if any),
Redemption Price, Purchase Price, Change in Control Purchase Price, Contingent Cash Interest, if any, and Contingent Additional Principal, if any, 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 and the resignation or removal of the Trustee. When the Trustee
incurs expenses after the occurrence of a Default specified in Section 6.01(4) or (5), the expenses including the reasonable charges and expenses of its counsel, 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 at Maturity of
the Securities at the time outstanding may remove the Trustee by so notifying the Trustee and the Company. The Company shall remove the Trustee if:



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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 satisfactory in form and substance to the retiring Trustee and 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 at Maturity of the Securities at the time outstanding may petition any court of competent jurisdiction at the expense of the Company 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 trust 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 shall at all times satisfy the requirements of TIA
Sections 310(a)(1) and 310(b). The Trustee (or its parent holding company) shall have a combined capital and surplus of at least $50,000,000 as set forth in its most recent published annual report of
condition. Nothing herein contained shall prevent the Trustee from filing with the Commission the application referred to in the penultimate paragraph of TIA Section 310(b).

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

ARTICLE VIII  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 or, if expressly permitted by the terms of the Securities or the Indenture, Common Stock (as applicable in accordance with the terms hereof) sufficient to pay all amounts due and
owing on 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, subject to applicable unclaimed property law. 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 and
the Trustee and the Paying Agent shall have no further liability to the

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Securityholders with respect to such money or securities for that period commencing after the return thereof.

ARTICLE IX  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:



Section 9.02 With Consent of Holders.With the written consent of the Holders of at least a majority in
aggregate Principal Amount at Maturity 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 to this Indenture or the Securities may not:



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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, 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 Trust Indenture Act.Every supplemental indenture executed pursuant to this Article
shall comply with the TIA.

Section 9.04 Revocation and Effect of Consents, Waivers and Actions.Until an amendment, waiver or other action
by Holders becomes effective, a consent thereto 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 amendment, waiver or other action is not made on the Security. However, any such Holder or subsequent Holder
may revoke the consent as to such Holder's Security or portion of the Security if the Trustee receives the notice of revocation before the date as of which the amendment, waiver or action is made
effective. After an amendment, 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 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 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 contained therein 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 receive, and (subject to the provisions of Section 7.01) shall be fully protected in relying
upon, in addition to the documents required by Section 14.04, an Officers' Certificate and an Opinion of Counsel stating that such amendment 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 X  CONVERSION

Section 10.01 Conversion Privilege.A Holder of a Security may convert such Security into shares of Common Stock
at any time during the period stated in paragraph 9 of the Securities, subject to the provisions of this Article 10. The number of shares of Common Stock issuable upon conversion of a
Security per $1,000 of Principal Amount at Maturity thereof (the "Conversion Rate") shall be that set forth in paragraph 9 in the Securities, subject to adjustment as herein set forth.

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A Holder may convert a portion of the Principal Amount at Maturity of a Security if the portion is $1,000 or an integral 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.

"Average Sale Price" means the average of the Sale Prices of the Common Stock for the shorter of



In
the event that the Ex-Dividend Time (or in the case of a subdivision, combination or reclassification, the effective date with respect thereto) with respect to a dividend, subdivision,
combination or reclassification to which Section 10.06(1), (2), (3) or (5) applies occurs during the period applicable for calculating "Average Sale Price" pursuant to the
definition in the preceding sentence, "Average Sale Price" shall be calculated for such period in a manner determined by the Board of Directors to reflect the impact of such dividend, subdivision,
combination or reclassification on the Sale Price of the Common Stock during such period.

"Time of Determination" means the time and date of the earlier of (i) the determination of stockholders entitled to receive
rights, warrants or options or a distribution, in each case, to which Section 10.07 or 10.08 applies and (ii) the time ("Ex-Dividend Time") immediately prior to the
commencement of "ex-dividend" trading for such rights, warrants or options or distribution on the New York Stock Exchange or such other national or regional exchange or market on which the
Common Stock is then listed or quoted.

Section 10.02 Conversion Procedure.To convert a Security, a Holder must satisfy the requirements in
paragraph 9 of the Securities. The date on which the Holder satisfies all those requirements is the conversion date (the "Conversion Date"). The Conversion Agent shall notify the Company of the
Conversion Date within one Business Day of the Conversion Date. The Company shall deliver to the Holder, through the Conversion Agent, no later than the fifth Business Day following the Conversion
Date, 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 representing such shares 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

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stock transfer books are open; such conversion shall be at the Conversion Rate 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 accrued interest or dividends on, or other distributions with respect to, any Common Stock except as provided in this Article 10. On
conversion of a Security, that portion of accrued Original Issue Discount (and CAP-OID, if any) and original issue discount, as imputed for United States federal income tax purposes
pursuant to Section 1.1275-4(b) of the Treasury Regulations and Contingent Additional Principal, if any, attributable to the period from the Issue Date to, but excluding, the
Conversion Date and (except as provided below) that portion of accrued Contingent Cash Interest attributable to the period from the last Contingent Cash Interest Payment Date (or Issue Date, if such
date has not occurred) ("Contingent Cash Interest Payment Date") to but excluding the Conversion Date with respect to the converted Security shall not be cancelled, extinguished or forfeited, but
rather shall be deemed to be paid in full to the Holder thereof through delivery of the Common Stock (together with the cash payment, if any, in lieu of fractional shares) in exchange for the Security
being converted pursuant to the provisions hereof; and the fair market value of such shares of Common Stock (together with any such cash payment in lieu of fractional shares) shall be treated as
delivered pro rata, to the extent thereof, first in exchange for accrued Original Issue Discount (and CAP-OID, if any) and original issue discount, as imputed for United States federal
income tax purposes pursuant to Section 1.1275-4(b) of the Treasury Regulations and accrued Contingent Additional Principal, if any, to, but excluding the Conversion Date and
accrued Contingent Cash Interest to, but excluding, the Conversion Date, and the balance, if any, of such cash and/or the fair market value of such Common Stock (together with any such cash payment in
lieu of fractional shares) shall be treated as delivered in exchange for the Issue Price of the Security being converted pursuant to the provisions hereof. Notwithstanding the foregoing, accrued but
unpaid Contingent Cash Interest will be payable upon conversion of Securities made concurrently with or after acceleration of Securities following an Event of Default.

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 at
Maturity of the Securities converted.

A
Security surrendered for conversion by a Holder during the period from the close of business on any Common Stock Record Date to the opening of business on the next Contingent Cash
Interest Payment Date must be accompanied by payment of an amount equal to the Contingent Cash Interest that the Holder is to receive on the Securities surrendered for conversion, unless the Company
has provided such Holder with a notice of redemption with respect to such Securities pursuant to Section 3.03 herein, in which case no such payment shall be made.

If
the last day on which a Security may be converted is a Legal Holiday, the Security may be surrendered on the next succeeding day that is not a Legal Holiday.

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 at Maturity to the unconverted portion of the Security surrendered.

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
1/1,000th of a share, by multiplying the Sale Price of the Common Stock, 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.

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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 under this
Article 10, 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.

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 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.If, after the Issue Date of the Securities, the Company:



then
the conversion privilege and the Conversion Rate in effect immediately prior to such action shall be adjusted so that the Holder of a Security thereafter converted may receive the number of
shares of Capital Stock of the Company which such Holder would have owned immediately following such action if such Holder had converted the Security immediately prior to such action.

The
adjustment shall become effective immediately after the record date in the case of a dividend or distribution and immediately after the effective date in the case of a
subdivision, combination or reclassification.

If
after an adjustment a Holder of a Security upon conversion of such Security may receive shares of two or more classes of Capital Stock of the Company, the Conversion Rate shall
thereafter be subject to adjustment upon the occurrence of an action taken with respect to any such class of Capital Stock as is contemplated by this Article 10 with respect to the Common
Stock, on terms comparable to those applicable to Common Stock in this Article 10.

Section 10.07 Adjustment for Rights Issue.If after the Issue Date of the Securities, the Company distributes
any rights, warrants or options to all holders of its Common Stock entitling them, for a

46

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period expiring within 60 days after the record date for such distribution, to purchase shares of Common Stock at a price per share less than the Sale Price of the Common Stock as of the Time
of Determination, the Conversion Rate shall be adjusted in accordance with the formula:

|R' = R x |  | (O + N)      
|-------- |  | -------------
|         |  | O + (N x P)/M

where:

R' =
the adjusted Conversion Rate.

R =
the current Conversion Rate.

O =
the number of shares of Common Stock outstanding on the record date for the distribution to which this Section 10.07 is being applied.

N =
the number of additional shares of Common Stock offered pursuant to the distribution.

P =
the offering price per share of the additional shares.

M =
the Average Sale Price, minus, in the case of (i) a distribution to which Section 10.06(4) applies or (ii) a distribution to which
Section 10.08 applies, for which, in each case, (x) the record date shall occur on or before the record date for the distribution to which this Section 10.07 applies and
(y) the Ex-Dividend Time shall occur on or after the date of the Time of Determination for the distribution to which this Section 10.07 applies, the fair market value (on the
record date for the distribution to which this Section 10.07 applies) of the:



The
Board of Directors shall determine fair market values for the purposes of this Section 10.07.

The
adjustment shall become effective immediately after the record date for the determination of shareholders entitled to receive the rights, warrants or options to which this
Section 10.07 applies. If all of the shares of Common Stock subject to such rights, warrants or options have not been issued when such rights, warrants or options expire, then the Conversion
Rate shall promptly be readjusted to the Conversion Rate which would then be in effect had the adjustment upon the issuance of such rights, warrants or options been made on the basis of the actual
number of shares of Common Stock issued upon the exercise of such rights, warrants or options.

No
adjustment shall be made under this Section 10.07 if the application of the formula stated above in this Section 10.07 would result in a value of R' that is equal to
or less than the value of R.

47

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(a) If,
after the Issue Date of the Securities, the Company distributes to all holders of its Common Stock any of its assets excluding distributions of Capital Stock or
equity interests referred to in Section 10.08(b), or evidences of indebtedness of the Company or any rights, warrants or options to purchase securities of the Company (including securities or
cash, but excluding (x) distributions of Capital Stock referred to in Section 10.06 and distributions of rights, warrants or options referred to in Section 10.07 and
(y) cash dividends or other cash distributions that are paid out of consolidated current net earnings or earnings retained in the business as shown on the books of the Company unless such cash
dividends or other cash distributions are Extraordinary Cash Dividends) the Conversion Rate shall be adjusted, subject to the provisions of Section 10.08(c), in accordance with the formula:

|R' = |  | R × M |  | 
|---- |  | ----- |  | 
|     |  | M-F   |  | 

where:

R' =
the adjusted Conversion Rate.

R =
the current Conversion Rate.

M =
the Average Sale Price, minus, in the case of a distribution to which Section 10.06(4) applies, for which (i) the record date shall occur on or before the
record date for the distribution to which this Section 10.08(a) applies and (ii) the Ex-Dividend Time shall occur on or after the date of the Time of Determination for the
distribution to which this Section 10.08(a) applies, the fair market value (on the
record date for the distribution to which this Section 10.08(a) applies) of any Capital Stock of the Company distributed in respect of each share of Common Stock in such Section 10.06(4)
distribution.

F =
the fair market value (on the record date for the distribution to which this Section 10.08(a) applies) of the assets, securities, rights, warrants or options to be
distributed in respect of each share of Common Stock in the distribution to which this Section 10.08(a) is being applied (including, in the case of cash dividends or other cash distributions
giving rise to an adjustment, all such cash distributed concurrently).

The
Board of Directors shall determine fair market values for the purposes of this Section 10.08(a).

The
adjustment shall become effective immediately after the record date for the determination of shareholders entitled to receive the distribution to which this
Section 10.08(a) applies.

For
purposes of this Section 10.08(a), the term "Extraordinary Cash Dividend" shall mean any cash dividend with respect to the Common Stock the amount of which, together with
the aggregate amount of cash dividends on the Common Stock to be aggregated with such cash dividend in accordance with the provisions of this paragraph, equals or exceeds the threshold percentage set
forth in item (i) below. For purposes of item (i) below, the "Measurement Period" with respect to a cash dividend on the Common Stock shall mean the 365 consecutive day period ending on
the date prior to the Ex-Dividend Time with respect to such cash dividend, and the "Relevant Cash Dividends" with respect to a cash dividend on the Common Stock shall mean the cash
dividends on the Common Stock with Ex-Dividend Times occurring in the Measurement Period.



48

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(b) If,
after the Issue Date of the Securities, the Company pays a dividend or makes a distribution to all holders of its Common Stock consisting of Capital Stock of
any class or series, or similar equity interests, of or relating to a Subsidiary or other business unit of the Company, the Conversion Rate shall be adjusted in accordance with the formula:



where:

R' =
the adjusted Conversion Rate.

R =
the current Conversion Rate.

M =
the average of the Post-Distribution Prices of the Common Stock for the 10 trading days commencing on and including the fifth trading day after the date on
which "ex-dividend trading" commences for such dividend or distribution on the principal United States exchange or market which such securities are then listed or quoted (the
"Ex-Dividend Date").

F =
the fair market value of the securities distributed in respect of each share of Common Stock for which this Section 10.08(b) shall mean the number of securities
distributed in respect of each share of Common Stock multiplied by the average of the Post-Distribution Prices of those securities distributed for the 10 trading days commencing on and
including the fifth trading day after the Ex-Dividend Date.

"Post-Distribution Price" of Capital Stock or any similar equity interest on any date means the closing per unit sale price
(or, if no closing sale price is reported, the average of the bid and ask prices or, if more than one in either case, the average of the average bid and the average ask prices) on such date for
trading of such units on a "when issued" basis without due bills (or similar concept) as reported in the composite transactions for the principal United States securities exchange on which such
Capital Stock or equity interest is traded or, if the Capital Stock or equity interest, as the case may be, is not listed on a United States national or regional securities exchange, as reported by
the National Association of Securities Dealers Automated Quotation System or by the National Quotation Bureau Incorporated; provided that if on any date such units have not traded on a "when issued"
basis, the Post-Distribution Price shall be the closing per unit sale price (or, if no closing sale price is reported, the average of the bid and ask prices or, if more than one in either
case, the average of the average bid and the average ask prices) on such date for trading of such units on a "regular way" basis without due bills (or similar concept) as reported in the composite
transactions for the principal United States securities exchange on which such Capital Stock or equity interest is traded or, if the Capital Stock or equity interest, as the case may be, is not listed
on a United States national or regional securities exchange, as reported by the National Association of Securities Dealers Automated Quotation System or by the National Quotation Bureau Incorporated.
In the absence of such quotation, the Company
shall be entitled to determine the Post-Distribution Price on the basis of such quotations, which reflect the post-distribution value of the Capital Stock or equity interests
as it considers appropriate.

49

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(c) In the event that, with respect to any distribution to which Section 10.08(a) would otherwise apply, the difference "M-F" as defined in the
formula set forth in Section 10.08(a) is less than $1.00 or "F" is equal to or greater than "M", then the adjustment provided by Section 10.08(a) shall not be made and in lieu thereof
the provisions of Section 10.14 shall apply to such distribution.

Section 10.09 When Adjustment May Be Deferred.No adjustment in the Conversion Rate need be made unless the
adjustment would require an increase or decrease of at least 1% in the Conversion Rate. 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 1/1,000th of a share, as the case may be (with one-half of a cent and
5/10,000ths of a share being rounded upward).

Section 10.10 When No Adjustment Required.No adjustment need be made for a transaction referred to in
Section 10.06, 10.07, 10.08, 10.14 or 10.19 if Securityholders are to participate in the transaction on a basis and with notice that the Board of Directors determines to be fair and appropriate
in light of the basis and notice on which holders of Common Stock participate in the transaction. Such participation by Securityholders may include participation upon conversion provided that an
adjustment shall be made at such time as the Securityholders are no longer entitled to participate.

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 pursuant to this Article 10 into cash, no adjustment need be made thereafter as to the cash. Interest will not accrue on the
cash. The Conversion Rate shall not be adjusted for any accrued Original Issue Discount (and CAP-OID, if any), Contingent Additional Principal, if any, or Contingent Cash Interest, if any.

Section 10.11 Notice of Adjustment.Whenever the Conversion Rate 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 and a certificate from the Company's independent public accountants briefly
stating the facts requiring the adjustment and the manner of computing it. The certificate shall 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 Increase.The Company from time to time may increase the Conversion Rate by any amount
for any period of time. Whenever the Conversion Rate is increased, the Company shall mail to Securityholders and file with the Trustee and the Conversion Agent a notice of the increase. The Company
shall mail the notice at least 15 days before the date the increased Conversion Rate takes effect. The notice shall state the increased Conversion Rate and the period it will be in effect.

A
voluntary increase of the Conversion Rate does not change or adjust the Conversion Rate otherwise in effect for purposes of Section 10.06, 10.07 or 10.08.

Section 10.13 Notice of Certain Transactions.If:



50

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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, binding share exchange, transfer, liquidation or dissolution. The Company shall file and mail the notice at least
20 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 Reorganization of Company; Special Distributions.If the Company is a party to a transaction
subject to Section 5.01 (other than a sale of all or substantially all of the assets of the Company in a transaction in which the holders of Common Stock immediately prior to such transaction
do not receive securities, cash or other assets of the Company or any other person) or a merger or binding share exchange which reclassifies or changes the outstanding Common Stock, the person
obligated to deliver securities, cash or other assets upon conversion of Securities shall enter into a supplemental indenture. If the issuer of securities deliverable upon conversion of Securities is
an Affiliate of the successor Company, that issuer shall join in the supplemental indenture.

The
supplemental indenture shall provide that the Holder of a Security may convert it into the kind and amount of securities, cash or other assets which such Holder would have
received immediately after the consolidation, merger, binding share exchange or transfer if such Holder had converted the Security immediately before the effective date of the transaction, assuming
(to the extent applicable) that such Holder (i) was not a constituent person or an Affiliate of a constituent person to such transaction; (ii) made no election with respect thereto; and
(iii) was treated alike with the plurality of non-electing Holders. The supplemental indenture shall provide for adjustments which shall be as nearly equivalent as may be practical
to the adjustments provided for in this Article 10. The successor Company shall mail to Securityholders a notice briefly describing the supplemental indenture.

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

If
the Company makes a distribution to all holders of its Common Stock of any of its assets, or Debt securities or any rights, warrants or options to purchase securities of the
Company that, but for the provisions of Section 10.08(c), would otherwise result in an adjustment in the Conversion Rate pursuant to the provisions of Section 10.08, then, from and after
the record date for determining the holders of Common Stock entitled to receive the distribution, a Holder of a Security that converts such Security in accordance with the provisions of this Indenture
shall upon such conversion be entitled to receive, in addition to the shares of Common Stock into which the Security is convertible, the kind and amount of securities, cash or other assets comprising
the distribution that such Holder would have received if such Holder had converted the Security immediately prior to the record date for determining the holders of Common Stock entitled to receive the
distribution.

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.

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

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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 Rate under more than one of Sections 10.06(4), 10.07 or 10.08, 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 10.06, second, the provisions of Section 10.08 and, third, the provisions of Section 10.07.

Section 10.18 Successive Adjustments.After an adjustment to the Conversion Rate under this Article 10,
any subsequent event requiring an adjustment under this Article 10 shall cause an adjustment to the Conversion Rate 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 ("Rights"), if any, and the certificates representing the Common Stock
issued upon such conversion shall bear such legends, if any, in each case as may be provided by the terms of any shareholder rights agreement adopted by the Company, as the same may be amended from
time to time (in each case, a "Rights Agreement"). Provided that such Rights Agreement requires that each share of Common Stock issued upon conversion of Securities at any time prior to the
distribution of separate certificates representing the Rights be entitled to receive such Rights, then, notwithstanding anything else to the contrary in this Article 10, there shall not be any
adjustment to the conversion privilege or Conversion Rate as a result of the issuance of Rights, the distribution of separate certificates representing the Rights, the exercise or redemption of such
Rights in accordance with any such Rights Agreement, or the termination or invalidation of such Rights.

ARTICLE XI  PAYMENT OF INTEREST

Section 11.01 Interest Payments.If applicable, Contingent Cash Interest, if any, on any Security that is
payable in cash, and is punctually paid or duly provided for, on the Contingent Cash Interest Payment Date shall be paid to the person in whose name that Security is registered at the close of
business on the Common Stock Record Date or Contingent Cash Record Payment Date, as the case may be, for such interest at the office or agency of the Company maintained for such purpose. Contingent
Cash Interest, if any, on any Security shall be paid in same-day funds by transfer to an account maintained by the payee located inside the United States, if the Trustee shall have
received proper wire transfer instructions from such payee not later than the related Common Stock Record Date or Contingent
Cash Interest Record Date accrual date, as the case may be, or, if no such instructions have been received, by check drawn on a bank in New York City mailed to the payee at its address set forth on
the Registrar's books. In the case of a permanent Global Security, Contingent Cash Interest, if any, payable on any applicable payment date will be paid to the Depositary, with respect to that portion
of such permanent Global Security held for its account by Cede & Co. for the purpose of permitting such party to credit the interest received by it in respect of such permanent Global Security
to the accounts of the beneficial owners thereof.

Section 11.02 Defaulted Interest.Except as otherwise specified with respect to the Securities, any Contingent
Cash Interest on any Security that is payable, but is not punctually paid or duly provided for, within 30 days following any applicable Contingent Cash Interest Payment Date (herein called
"Defaulted Interest", which term shall include any accrued and unpaid interest that has accrued on such defaulted amount in accordance with paragraph 1 of the Securities), shall forthwith cease
to be payable to the registered Holder thereof on the relevant Common Stock Record Date or Contingent Cash Interest Record Date, as the case may be, by virtue of having been such Holder, and such

52

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Defaulted Interest may be paid by the Company, at its election in each case, as provided in clause (1) or (2) below:



Section 11.03 Interest Rights Preserved.Subject to the foregoing provisions of this Article 11 and
Section 2.06, 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 Contingent Cash
Interest accrued and unpaid which were carried by such other Security.

ARTICLE XII  CONTINGENT CASH INTEREST

Section 12.01 Contingent Cash Interest.Commencing after June 12, 2006, the Company shall make Contingent
Cash Interest payments to the Holders of Securities, as set forth in Section 12.02 below, during any six month period from June 13 to December 12 and from December 13 to
June 12 (each a "Semi-annual Period") if,but only if, the average LYONs Market Price of one Security for the five trading days in
the relevant Five-Trading-Day Measurement Period equals 120% or more of the Relevant Value of such Security. During any Semi-annual Period when Contingent Cash
Interest is payable pursuant to this section, each Contingent Cash Interest payment due and payable on each $1,000 Principal Amount at Maturity of Security shall be calculated for any quarterly period
of the applicable Semi-annual Period, and in each instance shall equal the greater of (i) 0.0625% of the average LYONs Market Price for the relevant Five-Trading Day
Measurement Period or (ii) the sum of all Regular Cash Dividends paid by the Company per share on the Common Stock during the applicable quarter of such Semi-annual Period
multiplied by the Conversion Rate,provided,however,

53

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that if Regular Cash Dividends are not paid in such Semi-annual Period, the Contingent Cash Interest shall be paid semi-annually at a rate of .0.125% of the average LYONs
Market Price for the Semi-annual Period. Contingent Cash Interest shall accrue as of the 15th day preceding the last day of the relevant Semi-annual Period.

As
used in this Article 12, "Five-Trading-Day Measurement Period" means the five trading days ending on the third trading day immediately preceding the
first day of the applicable Semi-annual Period;provided,however, that if the Company
declares a Common Stock dividend for which the record date for such dividend (the "Common Stock Record Date") falls prior to the first day of the next Semi-annual Period, but the payment
date for such dividend for the Common Stock falls within such Semi-annual Period, then, the "Five-Trading-Day Measurement Period" shall mean the five trading days
ending on the third trading day immediately preceding such Common Stock Record Date. "Relevant Value" means the sum of the Issue Price, the accrued Original Issue Discount (and CAP-OID, if
any)
and accrued Contingent Additional Principal, if any, on such Security to the day immediately preceeding the first day of the applicable Semi-annual Period. "LYONs Market Price" means, as
of any date of determination, the average of the secondary market bid quotations per $1,000 Principal Amount at Maturity of Securities obtained by the Bid Solicitation Agent for $10 million
Principal Amount at Maturity of Securities at approximately 4:00 p.m., New York City time, on such determination date from three independent nationally recognized securities dealers (none of
which shall be an Affiliate of the Company) selected by the Company; ,provided,however, if
(a) at least three such bids are not obtained by the Bid Solicitation Agent or (b) in the Company's reasonable judgment, the bid quotations are not indicative of the secondary market
value of the Securities as of such determination date, then the LYONs Market Price for such determination date shall equal the product of (i) the Conversion Rate in effect as of such
determination date multiplied by (ii) the average Sale Price of the Common Stock for the five trading days ending on such determination date, appropriately adjusted to take into account the
occurrence, during the period commencing on the first of such trading days during such five trading day period and ending on such determination date, of any event described in Section 10.06,
10.07 or 10.08 (subject to the conditions set forth in Sections 10.09 and 10.10).

The
Original Issue Discount (and CAP-OID, if any) of the Securities will continue to accrue whether or not Contingent Cash Interest payments are made or are payable or any
Contingent Additional Principal accrues.

Section 12.02 Payment of Contingent Cash Interest; Contingent Cash Interest Rights Preserved.If payable,
Contingent Cash Interest shall be paid on the last day of such Semi-annual Period (in each case, a "Contingent Cash Interest Payment Date") or, if the Company pays a Regular Cash Dividend
on the Common Stock during a Semi-annual Period, on the payment date for the related Common Stock dividend. Contingent Cash Interest payments on any Security that are payable, and are
punctually paid or duly provided for, on any Contingent Cash Interest Payment Date shall be paid to the Person who is the Holder of that Security on the 15th day preceding the last day
of such Semi-annual Period (the "Contingent Cash Interest Record Date") or, if the Company pays regular cash dividends on the Common Stock during one quarter within such
Semi-annual Period, the Common Stock Record Date. Each payment of Contingent Cash Interest on any Security shall be paid (A) if such Security is held in the form of a Global
Security, in same-day funds by transfer to an account maintained by the payee located inside the United States, or (B) if such Security is held in the form of a Certificated Note,
by check, mailed to the address of such Holder as set forth in the Security Register. In the case of a Global Security, interest payable on any Contingent Cash Interest Payment Date will be paid to
the Depositary for the purpose of permitting DTC to credit the interest received by it in respect of such Global Security to the accounts of the beneficial owners thereof. If the Company only pays a
Regular Cash Dividend on the Common Stock during one quarter within such Semi-annual Period, the

54

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remaining Contingent Cash Interest payments will accrue and be payable as of the 15th day preceding the last day of such Semi-annual Period.

Upon
determination that Holders of Securities will be entitled to receive Contingent Cash Interest during a Semi-annual Period, prior to the start of such
Semi-annual Period, the Company will issue a press release and publish such information on its website as soon as practicable and provide written notification to the Trustee.

Section 12.03 Bid Solicitation Agent.The Bid Solicitation Agent shall solicit bids from securities dealers
which the Company indicates that it believes are willing to bid for the Securities. The Company initially appoints the Trustee to act as the Bid Solicitation Agent. The Company may change the Bid
Solicitation Agent at its discretion;provided,however, the Bid Solicitation Agent may not be an
Affiliate of the Company.

ARTICLE XIII  CONTINGENT ADDITIONAL PRINCIPAL

Section 13.01 Contingent Additional Principal.On June 12, 2004, if the Company's Stock Price Factor (as
defined below) is at or below the minimum Stock Price Factor thresholds set forth in the table below, then Contingent Additional Principal ("Contingent Additional Principal") together with
CAP-OID thereon, in lieu of Original Issue Discount, on the Securities shall accrue commencing on such date (as defined below). If, on June 12, 2004, the Stock Price Factor is
greater than the Stock Price Factor threshold, no Contingent Additional Principal (or CAP-OID thereon) shall accrue and Original Issue Discount shall accrue at the rate of 2%.

The
rate of accrual of Contingent Additional Principal per Security will be the rate which results from deducting an amount in accordance with the table below, from the Company's
Senior Debt Rate (as defined below), provided that in no event will such rate be greater than 9% or less than 2%. Contingent Additional Principal, if any, will accrue computed on a
semi-annual bond equivalent basis for a period of two years.

"Stock Price Factor" is the average of the Sale Prices of the Company's Common Stock for the 20 consecutive trading days ending on the
third trading day prior to June 12, 2004, expressed as a percentage of $81.59, subject to adjustment in accordance with Article 10 hereof.

"Senior Debt Rate" means the average of the interest rate quotations for a new issuance of the Company's two-year
semi-annual cash-pay unsecured senior debt obtained by the Rate Solicitation Agent for an issuance in an amount equal to the aggregate Issue Price of the Securities plus any
accrued Original Issue Discount through June 12, 2004 at approximately 4:00 p.m., New York City time, on the day three trading days prior to June 12, 2004 from three independent
nationally recognized securities dealers, (none of which shall be an Affiliate of the Company) selected by the Company;provided, however, that (a) if
the three such quotations cannot be obtained, then the average of two quotations shall be used in lieu thereof, and
(b) if only one such quotation can be obtained, such quotation shall be used. In the event that no quotations can be obtained, the Company's Senior Debt Rate will be determined by the good
faith determination of the Board of Directors.

55

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The table below indicates the amount to be deducted from the applicable Senior Debt Rate necessary to determine the rate of accrual of Contingent Additional Principal per Security
during the two years commencing June 12, 2004:

Stock Price Factor Threshold
If Senior Debt Rate at June 12, 2004 is:

|Amount to be Deducted
from Senior Debt
Rate: |  | <4.50% |   | >4.50%
to
>5.00% |   | >5.00%
to
>5.50% |   | >5.50%
to
>6.00% |   | >6.00%
to
>6.50% |   | >6.50%
to
>7.00% |   | >7.00%
to
>7.50% |   | >7.50%
to
>8.00% |   | >8.00%
to
>8.50% |   | >8.50%
to
9.00% |  
|-------------------------------------------- |  | ------ | - | ---------------- | - | ---------------- | - | ---------------- | - | ---------------- | - | ---------------- | - | ---------------- | - | ---------------- | - | ---------------- | - | --------------- | -
|-6.50%                                       |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   | <67             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-6.00%                                       |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   | <65              | % | <65             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-5.50%                                       |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   | <64              | % | <63              | % | <63             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-5.00%                                       |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   | <62              | % | <62              | % | <61              | % | <61             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-4.50%                                       |  |        |   |                  |   |                  |   |                  |   |                  |   | <61              | % | <60              | % | <60              | % | <59              | % | <59             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-4.00%                                       |  |        |   |                  |   |                  |   |                  |   | <59              | % | <59              | % | <58              | % | <58              | % | <56              | % | <56             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-3.50%                                       |  |        |   |                  |   |                  |   | <58              | % | <58              | % | <57              | % | <56              | % | <56              | % | <54              | % | <54             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-3.00%                                       |  |        |   |                  |   | <56              | % | <55              | % | <55              | % | <54              | % | <53              | % | <53              | % | <52              | % | <52             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-2.50%                                       |  |        |   | <52              | % | <52              | % | <52              | % | <52              | % | <51              | % | <50              | % | <50              | % | <49              | % | <49             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-2.00%                                       |  | <51    | % | <50              | % | <50              | % | <49              | % | <49              | % | <48              | % | <47              | % | <47              | % | <46              | % | <46             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-1.50%                                       |  | <47    | % | <47              | % | <47              | % | <46              | % | <45              | % | <44              | % | <44              | % | <44              | % | <43              | % | <43             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-1.00%                                       |  | <42    | % | <42              | % | <42              | % | <42              | % | <41              | % | <40              | % | <40              | % | <40              | % | <39              | % | <39             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-0.50%                                       |  | <38    | % | <38              | % | <37              | % | <37              | % | <36              | % | <36              | % | <35              | % | <35              | % | <35              | % | <35             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  
|-0.00%                                       |  | <31    | % | <31              | % | <31              | % | <30              | % | <30              | % | <30              | % | <29              | % | <29              | % | <29              | % | <29             | %
|                                             |  |        |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                  |   |                 |  

No Contingent Additional Principal will accrue after June 12, 2006, but thereafter Original Issue Discount shall continue to accrue at a
rate of 2% per year on (x) the Issue Price, (y) any accrued Original Issue Discount thereon, and (z) the amount of any Contingent Additional Principal accrued between
June 12, 2004 and June 12, 2006.

Section 13.02 Payment of Contingent Additional Principal.If payable, the Contingent Additional Principal shall
be paid on the Stated Maturity of the Securities. Contingent additional principal shall be calculated on a Semi-annual bond equivalent basis, using a 360-day year consisting of
twelve 30-day months.

Section 13.03 Notice.In the event that any Contingent Additional Principal accrues on the Securities, the
Company shall issue a press release to that effect which shall include, with respect to a Security, the rate of accrual of Contingent Additional Principal, the amount of any Contingent Additional
Principal, the revised Redemption Price, the revised Purchase Price, the revised Change in Control Purchase Price and the amount payable at the Stated Maturity. In addition, the Company shall publish
such information on its website or through such other comparable public medium as may be widely in use at that time. The Company shall also notify the Trustee annually in writing, at such time that
the Company files with the Trustee its annual reports or other information or documents, of any accrual of Contingent Additional Principal and the resulting increase in the Principal Amount at
Maturity per Security. Following its receipt of such notice, the Trustee shall provide such information to DTC for dissemination to the participants of DTC.

Section 13.04 Rate Solicitation Agent.The Rate Solicitation Agent shall solicit quotes from securities dealers
which the Company indicates that it believes are able to provide quotes for the Securities. The Company initially appoints the Trustee to act as the Rate Solicitation Agent. The

56

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Company may change the Rate Solicitation Agent at its discretion;provided,however, the Rate
Solicitation Agent may not be an Affiliate of the Company.

ARTICLE XIV  MISCELLANEOUS

Section 14.01 Trust Indenture Act Controls.If any provision of this Indenture limits, qualifies, or conflicts
with another provision which is required to be included in this Indenture by the TIA, the required provision shall control.

Section 14.02 Notices.Any request, demand, authorization, notice, waiver, consent or communication shall be in
writing and delivered in person or delivery by courier guaranteeing overnight delivery or mailed by first-class mail, postage prepaid, addressed as follows or transmitted by facsimile transmission
(confirmed by guaranteed overnight courier) to the following facsimile numbers:

if
to the Company:

Chiron
Corporation
              4560 Horton Street
              Emeryville, CA 94608-2916

Telephone
No. (510) 655-8730
              Facsimile No. (510) 655-9910
              Attention: Chief Financial Officer

with
a copy of any notice given pursuant to Article 6 to:

Sullivan &
Cromwell
              1888 Century Park East
              Los Angeles, CA 90067-1725

Telephone
No. (310) 712-6610
              Facsimile No. (310) 712-8800
              Attention: Frank Golay, Esq.

if
to the Trustee:

State
Street Bank and Trust Company
              of California, N.A.
              633 West 5th St., 12th Fl.
              Los Angeles, California 90071

Telephone
No. (213) 362-7338
              Facsimile No. (213) 362-7357
              Attention: Corporate Trust Administration

(Chiron
Corporation Liquid Yield Option Notes due 2031)

The
Company or the Trustee by notice given to the other in the manner provided above 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.

57

---

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.

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 14.03 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 14.04 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 if reasonably requested:



Section 14.05 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 to the extent required by the Trustee:



Section 14.06 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 14.07 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 also make reasonable rules for their respective functions.

Section 14.08 Calculations.The calculation of the Purchase Price, Change in Control Purchase Price, Conversion
Rate, Market Price, Sale Price of the Common Stock and each other calculation to be made hereunder (other than the LYONs Market Price) shall be the obligation of the Company. All calculations made by
the Company as contemplated pursuant to this Section 14.08 shall be final and binding on the Company and the Holders absent manifest error. The Trustee, Paying Agent, Conversion Agent, Bid
Solicitation Agent and Rate Solicitation Agent shall not be obligated to recalculate, recompute or confirm any such calculations.

58

---

Section 14.09 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, if the action to be taken on such date is a payment in
respect of the Securities, no Original Issue Discount or interest, if any, shall accrue for the intervening period.

Section 14.10 GOVERNING LAW.THIS INDENTURE AND THE SECURITIES WILL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE LAWS OF THE STATE OF NEW YORK.

Section 14.11 No Recourse Against Others.A director, officer, employee, agent, representative, stockholder or
equity holder, 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.

Section 14.12 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 14.13 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.

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

| |  | CHIRON CORPORATION
| |  | ------------------
| |  | By:               

| |  | STATE STREET BANK AND TRUST
COMPANY OF CALIFORNIA, N.A.,
as Trustee
| |  | -------------------------------------------------------------------
| |  | By:                                                                

59

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EXHIBIT A-1  [Form of Face of Global Security]

FOR PURPOSES OF SECTIONS 1273 AND 1275 OF THE INTERNAL REVENUE CODE, THIS SECURITY IS ISSUED WITH AN INDETERMINATE AMOUNT OF ORIGINAL ISSUE DISCOUNT FOR UNITED
STATES FEDERAL INCOME TAX PURPOSES. THE ISSUE DATE IS JUNE 12, 2001, AND THE YIELD TO MATURITY FOR PURPOSES OF ACCRUING ORIGINAL ISSUE DISCOUNT IS 6.37% PER ANNUM. THE HOLDER OF THIS SECURITY MAY
OBTAIN THE PROJECTED PAYMENT SCHEDULE BY SUBMITTING A WRITTEN REQUEST FOR SUCH INFORMATION TO: INVESTOR RELATIONS, CHIRON CORPORATION, 4560 HORTON STREET, EMERYVILLE, CA 94608-2916.

UNLESS
THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY TO THE ISSUER 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 THE DEPOSITORY TRUST COMPANY (AND ANY PAYMENT HEREON IS
MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY
OR TO ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

TRANSFERS
OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN WHOLE, BUT NOT IN PART, TO NOMINEES OF THE DEPOSITORY TRUST COMPANY, OR TO A SUCCESSOR THEREOF OR SUCH SUCCESSOR'S
NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN ARTICLE TWO OF THE INDENTURE REFERRED TO ON THE REVERSE
HEREOF.

THIS
SECURITY AND THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS SECURITY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR
ANY STATE SECURITIES LAWS. NEITHER THIS SECURITY, THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN OR THEREIN MAY BE REOFFERED, SOLD,
ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION.

THE
HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE HEREOF, AGREES TO OFFER, SELL, OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE RESTRICTION TERMINATION DATE"), WHICH
IS TWO YEARS AFTER THE LATER OF THE LAST DAY SECURITIES OF THIS ISSUE WERE ISSUED AND THE LAST DATE ON WHICH CHIRON CORPORATION (THE "COMPANY" OR THE "ISSUER") OR ANY AFFILIATE OF THE COMPANY WAS THE
OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY) ONLY (A) TO THE COMPANY OR ANY SUBSIDIARY THEREOF, (B) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE
144A, TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED
INSTITUTIONAL BUYER TO WHICH NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (C) TO AN INSTITUTIONAL "ACCREDITED

A11

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INVESTOR" WITHIN THE MEANING OF SUBPARAGRAPH (A)(1), (2), (3) OR (7) OF RULE 501 UNDER THE SECURITIES ACT THAT IS ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT, OR FOR THE ACCOUNT OF SUCH AN
INSTITUTIONAL "ACCREDITED INVESTOR," FOR INVESTMENT PURPOSES AND NOT WITH A VIEW TO, OR FOR OFFER OR SALE IN CONNECTION WITH, ANY DISTRIBUTION IN VIOLATION OF THE SECURITIES ACT, (D) PURSUANT
TO A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT OR (E) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT,
SUBJECT TO THE COMPANY'S AND THE TRUSTEE'S RIGHT PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO CLAUSE (C) OR (E) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATION
AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM, AND IN EACH OF THE FOREGOING CASES, A CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON THE OTHER SIDE OF THIS SECURITY IS COMPLETED AND DELIVERED
BY THE TRANSFEROR TO THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.

THE
FOREGOING LEGEND MAY BE REMOVED FROM THIS SECURITY ON SATISFACTION OF THE CONDITIONS SPECIFIED IN THE INDENTURE.

A12

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CHIRON CORPORATION
Liquid Yield Option Note due 2031
(Zero Coupon-Senior)

|No. R-
Issue Date: June 12, 2001
Issue Price: $550.45
(for each $1,000 Principal
Amount at Maturity) |  | CUSIP: 170040 AD1
Original Issue Discount: $449.55
(for each $1,000 Principal
Amount at Maturity)
|---------------------------------------------------------------------------------------------------- |  | -------------------------------------------------------------------------------------------------

CHIRON
CORPORATION, a Delaware corporation, promises to pay to Cede & Co. or registered assigns, the Principal Amount at Maturity of
 DOLLARS ($) on June 12, 2031.

This
Security shall not bear interest except as specified on the other side of this Security. Original Issue Discount will accrue as specified on the other side of this Security. This
Security is convertible as specified on the other side of this Security.

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

|Dated: June 12, 2001 |  | CHIRON CORPORATION
|-------------------- |  | ------------------
|                     |  |                   
|                     |  |                   
|                     |  |                   
|                     |  | By:               
|                     |  |                   

TRUSTEE'S
CERTIFICATE OF
    AUTHENTICATION

STATE
STREET BANK and TRUST COMPANY
OF CALIFORNIA, N.A.,
as Trustee, certifies that this
is one of the Securities referred
to in the within-mentioned Indenture.

|    |  |                    |  | 
|--- |  | ------------------ |  | 
|By: |  | Authorized Officer |  | 

Dated:
June 12, 2001

A13

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Liquid Yield Option Note due 2031
(Zero CouponSenior)

This
Security shall not bear interest, except as specified in this paragraph or in paragraph 5. If the Principal Amount at Maturity hereof or any portion of such Principal
Amount at Maturity 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 6 hereof, upon the date set for payment of the Purchase Price or Change in Control Purchase Price pursuant to paragraph 7 hereof or upon the Stated Maturity of this Security)
or if Contingent Cash Interest, if any, due hereon or any portion of such interest is not paid when due in accordance with paragraph 5.A hereof, or if Contingent Additional Payment, if any, due
hereon or any portion of such Contingent Additional Payment is not paid when due in accordance with paragraph 5.B hereof, then in each such case the overdue amount shall, to the extent
permitted by law, bear interest at the rate of 2.0% per annum, compounded semiannually, which interest shall accrue from the date such overdue amount was originally 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. The accrual of such interest on overdue amounts shall be in lieu of, and not in
addition to, the continued accrual of Original Issue Discount (and CAP-OID, if any) and Contingent Additional Principal.

Original
Issue Discount (the difference between the Issue Price and the Principal Amount at Maturity of the Security), in the period during which a Security remains outstanding, shall
accrue at 2.0% per annum, plus any previously accrued Original Issue Discount plus the amount of any Contingent Additional Principal, plus any CAP-OID thereon, on a semi-annual
bond equivalent basis using a 360-day year composed of twelve 30-day months, from the Issue Date of this Security.

Subject
to the terms and conditions of the Indenture, the Company will make payments in respect of Redemption Prices, Purchase Prices, Change in Control Purchase Prices and at Stated
Maturity to Holders who surrender Securities to a Paying Agent to collect such payments in respect of the Securities. In addition, the Company will pay Contingent Cash Interest owing, if any, and
Contingent Additional Principal (and CAP-OID thereon), if any. The Company will pay any cash amounts in Cash. However, the Company may make such cash payments by check payable in such
money.

Initially,
State Street Bank and Trust Company of California, N.A., a national banking association organized under the laws of the United States (the "Trustee"), will act as Paying
Agent, Conversion Agent, Registrar, Bid Solicitation Agent and Rate Solicitation Agent. The Company may appoint and change any Paying Agent, Conversion Agent, Registrar or co-registrar or
Bid Solicitation Agent or Rate Solicitation Agent without notice, other than notice to the Trustee except that the Company will maintain at least one Paying Agent in the Borough of Manhattan, City of
New York, which shall initially be an office or agency of 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. None of the Company, any of its Subsidiaries or any of their Affiliates shall act as Bid Solicitation Agent or Rate Solicitation Agent.

The
Company issued the Securities under an Indenture dated as of June 12, 2001 (the "Indenture"), between the Company and the Trustee. The terms of the Securities include those
stated in the Indenture and those made part of the Indenture by reference to the Trust Indenture Act of 1939, as in effect from time to time (the "TIA"). Capitalized terms used herein and not defined
herein

A14

---

have the meanings ascribed thereto in the Indenture. The Securities are subject to all such terms, and Securityholders are referred to the Indenture and the TIA for a statement of those terms.

The
Securities are general unsecured and unsubordinated obligations of the Company limited to $730,000,000 ($915,000,000 aggregate Principal Amount at Maturity, if the
over-allotment option granted to the initial purchaser of the Securities is exercised in full) aggregate Principal Amount at Maturity (not including Contingent Additional Principal, if
any, CAP-OID thereon and subject to Section 2.07 of the Indenture) and will rank equally in right of payment to all of the Company's present and future unsecured and unsubordinated
indebtedness. The Indenture does not limit other indebtedness of the Company, secured or unsecured.

A.Contingent Cash Interest.Subject to the conditions of the Indenture and the accrual and record date
provisions specified in this paragraph 5.A, the Company shall pay Contingent Cash Interest to the Holders during any six-month period (a "Contingent Cash Interest Period") from
June 13 to December 12 and from December 13 to June 12, with the initial six-month period commencing after
June 12, 2006, if the average LYONs Market Price for the Five-Trading-Day Measurement Period with respect to such Contingent Cash Interest Period equals 120% or more of
the sum of the Issue Price of a Security, Original Issue Discount accrued thereon to the day immediately preceding the first day of the relevant Contingent Interest Period and Contingent Additional
Principal (and CAP-OID thereon), if any, for such Security to the day immediately preceding the first day of the applicable six-month period.

Contingent
Cash Interest, if any, will accrue and be payable to holders of this Security as of the 15th day preceding the last day of the applicable
six-month period. Original Issue Discount will continue to accrue at 2.0% whether or not Contingent Cash Interest is paid.

The
amount of Contingent Cash Interest payable per $1,000 Principal Amount at Maturity hereof in respect of any quarterly period of the applicable Contingent Cash Interest Period
shall equal the greater of (x) 0.0625% of the average LYONs Market Price for the relevant Five-Trading-Day Measurement Period and (y) the sum of all Regular Cash
Dividends paid by the Company per share of Common Stock during that three-month period of the applicable Contingent Cash Interest Period multiplied by the number of shares of Common Stock into which
$1,000 Principal Amount at Maturity hereof is convertible pursuant to paragraph 9 hereof as of the accrual date for such Contingent Cash Interest; provided, however, that if Regular Cash
Dividends are not paid in such Semi-annual Period, the Contingent Cash Interest shall be paid semi-annually at a rate of 0.125% of the average LYONs Market Price for the
Semi-annual Period. Contingent Cash Interest shall accrue as of the 15th day preceding the last day of the relevant Semi-annual Period.

Upon
determination that Holders will be entitled to receive Contingent Cash Interest during a Contingent Cash Interest Period the Company shall issue a press release and publish such
information on its web site, or other medium publicly available, as soon as practicable.

B.Contingent Additional Principal.Subject to the conditions set forth in the Indenture, on
June 12, 2004 if the Stock Price Factor is at or below the minimum Stock Price Factor thresholds (as set forth in Article 13 of the Indenture) on that date, Contingent Additional
Principal on the Securities shall accrue, in lieu of Original Issue Discount, commencing on such date. If, on June 12, 2004, the Stock Price Factor exceeds the Stock Price threshold, no
Contingent Additional Principal (and CAP-OID thereon) shall accrue and Original Issue Discount as provided in the Indenture.

The
rate of accrual of Contingent Additional Principal per Security will be the rate which results from deducting an amounts in accordance with the table in Article 13, from
the Company's Senior Debt Rate (as defined below), provided that in no event will such rate be greater than 9% or less than 2%.

A15

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Contingent Additional Principal, if any, shall be payable on the Stated Maturity date of the Securities. Contingent Additional Principal shall be calculated on a
Semi-annual bond equivalent basis, using a 360-day year consisting of twelve 30-day months. No Contingent Additional Principal will accrue after June 12,
2006.

In
the event that any Contingent Additional Principal accrues on the Securities, the Company shall issue a press release to that effect which shall include with respect to a Security
the rate of accrual of Contingent Additional Principal, the amount of any Contingent Additional Principal, the revised Redemption Price, the revised Purchase Price, the revised Change in Control
Purchase Price and the amount payable at the Stated Maturity. In addition, the Company shall publish such information on its website or through such other comparable public medium as may be widely in
use at that time. The Company shall also notify the Trustee annually in writing, at such time that the Company files with the Trustee its annual reports or other information or documents pursuant to
the Indenture, of any accrual of Contingent Additional Principal and the resulting increase in the Principal Amount at Maturity per Security. Following its receipt of such notice, the Trustee shall
provide such information to DTC for dissemination to the participants of DTC.

No
sinking fund is provided for the Securities. The Securities are redeemable as a whole, or from time to time in part, at any time at the option of the Company in accordance with
Article 3 of the Indenture at the Redemption Prices set forth below, provided that the Securities are not redeemable prior to June 12, 2006.

The
table below shows Redemption Prices of a Security per $1,000 Principal Amount at Maturity on the dates shown below and at Stated Maturity, which prices reflect the Issue Price
plus accrued Original Issue Discount calculated to each such date and assumes that no Contingent Additional Principal is payable. The Redemption Price of a Security redeemed between such dates shall
include an additional amount reflecting the additional Original Issue Discount accrued since the next preceding date in the table:

|Redemption Date |  | (1)
LYON
Issue Price |  | (2)
Accrued Original Issue
Discount |  | (3)
Redemption Price
(1) + (2)
|--------------- |  | -------------------- |  | ----------------------------------- |  | ------------------------------
|June 12,        |  |                      |  |                                     |  |                               
|2006            |  | 550.45               |  | 57.59                               |  | 608.04                        
|2007            |  | 550.45               |  | 69.81                               |  | 620.26                        
|2008            |  | 550.45               |  | 82.28                               |  | 632.73                        
|2009            |  | 550.45               |  | 95.00                               |  | 645.45                        
|2010            |  | 550.45               |  | 107.97                              |  | 658.42                        
|2011            |  | 550.45               |  | 121.20                              |  | 671.65                        
|2012            |  | 550.45               |  | 134.70                              |  | 685.15                        
|2013            |  | 550.45               |  | 148.48                              |  | 698.93                        
|2014            |  | 550.45               |  | 162.52                              |  | 712.97                        
|2015            |  | 550.45               |  | 176.85                              |  | 727.30                        
|2016            |  | 550.45               |  | 191.47                              |  | 741.92                        
|2017            |  | 550.45               |  | 206.39                              |  | 756.84                        
|2018            |  | 550.45               |  | 221.60                              |  | 772.05                        
|2019            |  | 550.45               |  | 237.12                              |  | 787.57                        
|2020            |  | 550.45               |  | 252.95                              |  | 803.40                        
|2021            |  | 550.45               |  | 269.09                              |  | 819.54                        
|2022            |  | 550.45               |  | 285.57                              |  | 836.02                        
|2023            |  | 550.45               |  | 302.37                              |  | 852.82                        

A16

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|2024               |  | 550.45 |  | 319.51 |  | 869.96  
|------------------ |  | ------ |  | ------ |  | --------
|2025               |  | 550.45 |  | 337.00 |  | 887.45  
|2026               |  | 550.45 |  | 354.84 |  | 905.29  
|2027               |  | 550.45 |  | 373.03 |  | 923.48  
|2028               |  | 550.45 |  | 391.60 |  | 942.05  
|2029               |  | 550.45 |  | 410.53 |  | 960.98  
|2030               |  | 550.45 |  | 429.85 |  | 980.30  
|At Stated Maturity |  | 550.45 |  | 449.55 |  | 1,000.00

Subject
to the terms and conditions of the Indenture, the Company shall become obligated to purchase, at the option of the Holder, the Securities held by such Holder on the following
Purchase Dates and at the following Purchase Prices per $1,000 Principal Amount at Maturity, upon delivery of a Purchase Notice containing the information set forth in the Indenture, at any time from
the opening of business on the date that is 20 Business Days prior to such Purchase Date until the close of business on such Purchase Date and upon delivery of the Securities to the Paying Agent by
the Holder as set forth in the Indenture:

|Purchase Date |  | Purchase Price
|------------- |  | --------------
|June 12, 2004 |  | $584.31       
|June 12, 2006 |  | $608.04       
|June 12, 2011 |  | $671.65       
|June 12, 2016 |  | $741.92       
|June 12, 2021 |  | $819.54       
|June 12, 2026 |  | $905.29       

The
Purchase Price (equal to the Issue Price plus accrued Original Issue Discount for the Purchase Date noted in the above table plus Contingent Additional Principal, if any, and
CAP-OID thereon to the Purchase Date) may be paid, at the option of the Company, in cash or by the issuance and delivery of shares of Common Stock of the Company, or in any combination
thereof in accordance with the Indenture.

At
the option of the Holder and subject to the terms and conditions of the Indenture, the Company shall become obligated to purchase the Securities held by such Holder no later than
35 Business Days after the occurrence of a Change in Control (as defined in Section 3.08) occurring on or prior to June 12, 2006, but in no event prior to the date on which such Change
in Control occurs, for a Change in Control Purchase Price equal to the Issue Price, plus accrued Original Issue Discount (and CAP-OID, if any) and, if applicable, Contingent Additional
Principal to but not including the Change in Control Purchase Date, which Change in Control Purchase Price shall be paid in cash.

A
third party may make the offer and purchase of the Securities in lieu of the Company in accordance with the Indenture.

In
addition to the Purchase Price or Change in Control Purchase Price, as the case may be, payable with respect to all Securities or portions thereof to be purchased as of the
Purchase Date or the Change in Control Purchase Date, as the case may be, the Holders of such Securities (or portions thereof) shall be entitled to receive accrued and unpaid Contingent Cash Interest,
if any, with respect thereto, which Contingent Cash Interest shall be paid in cash promptly following the later of the Purchase Date or the Change in Control Purchase Date, as the case may be, and the
time of delivery of such Securities to the Paying Agent pursuant to the Indenture.

A17

---

Holders have the right to withdraw any Purchase Notice or Change in Control Purchase Notice, as the case may be, by delivering to the Paying Agent a written notice of withdrawal in
accordance with the provisions of the Indenture.

If
cash (and/or securities if permitted under the Indenture) sufficient to pay the Purchase Price or Change in Control Purchase Price, as the case may be, of, together with any
accrued and unpaid Contingent Cash Interest with respect to, all Securities or portions thereof to be purchased as of the Purchase Date or the Change in Control Purchase Date, as the case may be, is
deposited with the Paying Agent on the Business Day following the Purchase Date or the Change in Control Purchase Date, as the case may be, Original Issue Discount (and CAP-OID, if any),
Contingent Cash Interest, if any, and Contingent Additional Principal, if any, shall cease to accrue on such Securities (or portions thereof) on such Purchase Date or Change in Control Purchase Date,
as the case may be, and the
Holder thereof shall have no other rights as such (other than the right to receive the Purchase Price or Change in Control Purchase Price, as the case may be, and accrued and unpaid Contingent Cash
Interest, if any, upon surrender of such Security).

Notice
of redemption 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 of, and accrued and unpaid Contingent Cash Interest, if any, with respect to, 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 such Redemption Date, Original Issue Discount (and CAP-OID, if any), Contingent Cash Interest,
if any, and Contingent Additional Principal shall cease to accrue on such Securities or portions thereof. Securities in denominations larger than $1,000 of Principal Amount at Maturity may be redeemed
in part but only in integral multiples of $1,000 of Principal Amount at Maturity.

Subject
to the next two succeeding sentences, a Holder of a Security may convert it into Common Stock of the Company at any time before the close of business on June 12, 2031.
If the Security is called for redemption, the Holder may convert it only until the close of business on the second business day immediately preceding the Redemption Date. A Security in respect of
which a Holder has delivered a Purchase Notice or Change in Control Purchase Notice exercising the option of such Holder to require the Company to purchase such Security may be converted only if such
notice of exercise is withdrawn in accordance with the terms of the Indenture.

The
initial Conversion Rate is 7.1613 shares of Common Stock per $1,000 Principal Amount at Maturity, subject to adjustment upon occurrence of certain events described in the
Indenture. The Company will deliver cash in lieu of any fractional share of Common Stock.

A
Security surrendered for conversion by a Holder during the period from the close of business on any Common Stock Record Date to the opening of business on the next Contingent Cash
Interest Payment Date must be accompanied by payment of an amount equal to the Contingent Cash Interest that the Holder is to receive on the Securities surrendered for conversion, unless the Company
has provided such Holder with a notice of redemption with respect to such Securities pursuant to Section 3.03 herein, in which case no such payment shall be made.

To
convert a Security, a Holder must (1) complete and manually sign the conversion notice below (or complete and manually sign a facsimile of such notice) and deliver such
notice to the Conversion Agent, (2) surrender the Security to the 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.

A18

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A Holder may convert a portion of a Security if the Principal Amount at Maturity of such portion is $1,000 or an integral multiple of $1,000. No payment or adjustment will be made for
accrued interest or dividends on, or other distributions with respect to, any Common Stock except as provided in Article 10. On conversion of a Security, that portion of accrued Original Issue
Discount (and CAP-OID, if any) and original issue discount, as imputed for United States federal income tax purposes pursuant to Section 1.1275-4(b) of the Treasury
Regulations and Contingent Additional Principal, if any, attributable to the period from the Issue Date to, but excluding, the Conversion Date and (except as provided below) that portion of accrued
Contingent Cash Interest attributable to the period from the last Contingent Cash Interest Payment Date (or Issue Date, if such date has not occurred) to but excluding the Conversion Date with respect
to the converted Security shall not be cancelled, extinguished or forfeited, but rather shall be deemed to be paid in full to the Holder thereof through delivery of the Common Stock (together with the
cash payment, if any, in lieu of fractional shares) in exchange for the Security being converted pursuant to the provisions hereof; and the fair market value of such shares of Common Stock (together
with any such cash payment in lieu of fractional shares) shall be treated as delivered pro rata, to the extent thereof, first in exchange for accrued Original Issue Discount (and CAP-OID,
if any) and original issue discount, as imputed for United States federal income tax purposes pursuant to Section 1.1275-4(b) of the Treasury Regulations and accrued Contingent
Additional Principal, if any, to, but excluding the Conversion Date and accrued Contingent Cash Interest to, but excluding, the Conversion Date, and the balance, if any, of such cash and/or the fair
market value of such Common Stock (together with any such cash payment in lieu of fractional shares) shall be treated as delivered in exchange for the Issue Price of the Security being converted
pursuant to the provisions hereof. Notwithstanding the foregoing, accrued but unpaid Contingent Cash Interest will be payable upon conversion of Securities made concurrently with or after acceleration
of Securities following an Event of Default.

The
Conversion Rate will be adjusted for dividends or distributions on Common Stock payable in Common Stock or other Capital Stock; subdivisions, combinations or certain
reclassifications of Common Stock; distributions to all holders of Common Stock of certain rights to purchase Common Stock for a period expiring within 60 days at less than the Sale Price at
the Time of Determination; and distributions to such holders of assets or Debt securities of the Company or certain rights to purchase securities of the Company (excluding certain cash dividends or
distributions). However, no adjustment need be made if Securityholders may participate in the transaction or in certain other cases. The Company from time to time may voluntarily increase the
Conversion Rate.

In
the event that the Company declares a dividend or distribution described in Section 10.07 of the Indenture, or a dividend or a distribution described in Section 10.08
of the Indenture where the fair market value of such dividend or distribution per share of Common Stock, as determined in the Indenture, exceeds 15% of the Sale Price of the Common Stock on the day
preceding the date of declaration for such dividend or distribution, the Company shall give notice to the Holders, which shall not be less than 20 days prior to the Ex-Dividend Date
for such dividend or distribution.

If
the Company is a party to a consolidation, merger or binding share exchange or a transfer of all or substantially all of its assets, or upon certain distributions described in the
Indenture, the right to convert a Security into Common Stock may be changed into a right to convert it into the kind and amount of securities, cash or other assets of the Company or another person
which the Holder would have received if the Holder had converted its Securities immediately prior to the transaction.

The
Conversion Rate will not be adjusted for any accrued Contingent Cash Interest, if any, or Contingent Additional Principal (and CAP-OID thereon), if any.

A19

---

Except
as otherwise specified with respect to the Securities, any Defaulted Interest on any Security shall forthwith cease to be payable to the registered Holder thereof on the
relevant Common Stock Record Date or Contingent Cash Interest Record Date, as the case may be, by virtue of having been such Holder, and such Defaulted Interest may be paid by the Company as provided
for in Section 10.02 of the Indenture.

The
Securities are in fully registered form, without coupons, in denominations of $1,000 of Principal Amount at Maturity and integral 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 Purchase Notice or Change in Control Purchase 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 the mailing of a notice of redemption of Securities to be redeemed.

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

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, subject to applicable unclaimed property laws. 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.

Subject
to certain exceptions set forth in the Indenture, (i) the Indenture or the Securities may only be amended with the written consent of the Holders of at least a majority
in aggregate Principal Amount at Maturity of the Securities at the time outstanding and (ii) certain Defaults may be waived with the written consent of the Holders of a majority in aggregate
Principal Amount at Maturity 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, omission, defect or inconsistency, or to comply with Article 5 or Section 10.14 of the Indenture, to secure the Company's
obligations under this Security or to add to the Company's covenants for the benefit of the Securityholders or to surrender any right or power conferred, to comply with any requirement of the SEC in
connection with the qualification of the Indenture under the TIA, or as necessary in connection with the registration of the Securities under the Securities Act or to make any change that does not
adversely affect the rights of any of the Holders.

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 indemnity or security reasonably satisfactory to it. Subject to certain limitations, Holders of a majority in aggregate Principal Amount at Maturity of the Securities at the time outstanding
may direct the

A110

---

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 Sections 6.01(1) and
(2) of the Indenture if it determines that withholding notice is in their interests.

Subject
to certain limitations imposed by the TIA, 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.

A
director, officer, employee, agent, representative, stockholder or equity holder, 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.

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

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).

THIS
INDENTURE AND THE SECURITIES WILL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

A111

---

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:



|ASSIGNMENT FORM                                                                                                                                                                                                                                                                                                                     |  | CONVERSION NOTICE                                                                                                                                                                                                                                                                                                                                                                                                                           
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|To assign this Security, fill in the form below:
I or we assign and transfer this Security to(Insert assignee's soc. sec. or tax ID no.)(Print or type assignee's name, address and zip code)
and irrevocably appoint agent to transfer this Security on the books of the Company. The agent may substitute another to act for him. |  | To convert this Security into Common Stock of the Company, check the box:  / /
To convert only part of this Security, state the Principal Amount at Maturity to be converted (which must be $1,000 or an integral multiple of $1,000):
$If you want the stock certificate made out in another person's name, fill in the form below:(Insert other person's soc. sec. or tax ID no.)(Print or type other person's name, address and zip code)

|                                                                      
|----------------------------------------------------------------------
|Date:                                                                 
|(Sign exactly as your name appears on the other side of this Security)

A112

---



EXHIBIT A-2  [Form of Certificated Security]

FOR PURPOSES OF SECTIONS 1273 AND 1275 OF THE INTERNAL REVENUE CODE, THIS SECURITY IS ISSUED WITH AN INDETERMINATE AMOUNT OF ORIGINAL ISSUE DISCOUNT FOR UNITED
STATES FEDERAL INCOME TAX PURPOSES. THE ISSUE DATE IS JUNE 12, 2001, AND THE YIELD TO MATURITY FOR PURPOSES OF ACCRUING ORIGINAL ISSUE DISCOUNT IS 6.37% PER ANNUM. THE HOLDER OF THIS SECURITY MAY
OBTAIN THE PROJECTED PAYMENT SCHEDULE BY SUBMITTING A WRITTEN REQUEST FOR SUCH INFORMATION TO: INVESTOR RELATIONS, CHIRON CORPORATION, 4560 HORTON STREET, EMERYVILLE, CALIFORNIA
94608-2916.

[INCLUDE
IF SECURITY IS A CERTIFICATED SECURITY TO BE HELD BY AN INSTITUTIONAL ACCREDITED INVESTORIN CONNECTION WITH ANY TRANSFER, THE HOLDER WILL DELIVER TO
THE REGISTRAR AND TRANSFER AGENT SUCH CERTIFICATES AND OTHER INFORMATION AS SUCH TRANSFER AGENT MAY REASONABLY REQUIRE TO CONFIRM THAT THE TRANSFER COMPLIES WITH THE FOLLOWING
RESTRICTIONS.]

THIS
SECURITY AND THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS SECURITY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR
ANY STATE SECURITIES LAWS. NEITHER THIS SECURITY, THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN OR THEREIN MAY BE REOFFERED, SOLD,
ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION.

THE
HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE HEREOF, AGREES TO OFFER, SELL, OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE RESTRICTION TERMINATION DATE"), WHICH
IS TWO YEARS AFTER THE LATER OF THE LAST DAY SECURITIES OF THIS ISSUE WERE ISSUED AND THE LAST DATE ON WHICH CHIRON CORPORATION (THE "COMPANY" OR THE "ISSUER") OR ANY AFFILIATE OF THE COMPANY WAS THE
OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY) ONLY (A) TO THE COMPANY OR ANY SUBSIDIARY THEREOF, (B) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE
144A, TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT
THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHICH NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (C) TO AN
INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN THE MEANING OF SUBPARAGRAPH (A)(1), (2), (3) OR (7) OF RULE 501 UNDER THE SECURITIES ACT THAT IS ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT, OR FOR
THE ACCOUNT OF SUCH AN INSTITUTIONAL "ACCREDITED INVESTOR," FOR INVESTMENT PURPOSES AND NOT WITH A VIEW TO, OR FOR OFFER OR SALE IN CONNECTION WITH, ANY DISTRIBUTION IN VIOLATION OF THE SECURITIES
ACT, (D) PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT OR (E) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS
OF THE SECURITIES ACT, SUBJECT TO THE COMPANY'S AND THE TRUSTEE'S RIGHT PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO CLAUSE (C) OR (E) TO REQUIRE THE DELIVERY OF AN OPINION OF
COUNSEL, CERTIFICATION AND/OR OTHER

A21

---

INFORMATION SATISFACTORY TO EACH OF THEM, AND IN EACH OF THE FOREGOING CASES, A CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON THE OTHER SIDE OF THIS SECURITY IS COMPLETED AND DELIVERED BY THE
TRANSFEROR TO THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.

THE FOREGOING LEGEND MAY BE REMOVED FROM THIS SECURITY ON SATISFACTION OF THE CONDITIONS SPECIFIED IN THE INDENTURE.

A22

---

CHIRON CORPORATION
Liquid Yield Option Note due 2031
(Zero CouponSenior)

|No. R-
Issue Date: June 12, 2001
Issue Price: $550.45
(for each $1,000 Principal
Amount at Maturity) |  | CUSIP: 170040 AD1
Original Issue Discount: $449.55
(for each $1,000 Principal
Amount at Maturity)
|---------------------------------------------------------------------------------------------------- |  | -------------------------------------------------------------------------------------------------

CHIRON
CORPORATION, a Delaware corporation, promises to pay to Cede & Co. or registered assigns, the Principal Amount at Maturity of
 DOLLARS ($) on June 12, 2031.

This
Security shall not bear interest except as specified on the other side of this Security. Original Issue Discount will accrue as specified on the other side of this Security. This
Security is convertible as specified on the other side of this Security.

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

|Dated: June 12, 2001 |  | CHIRON CORPORATION
|-------------------- |  | ------------------
|                     |  |                   
|                     |  |                   
|                     |  | By:               
|                     |  |                   

TRUSTEE'S
CERTIFICATE OF
    AUTHENTICATION

STATE
STREET BANK and TRUST COMPANY
OF CALIFORNIA, N.A.,
as Trustee, certifies that this
is one of the Securities referred
to in the within-mentioned Indenture.

|    |  |                    |  | 
|--- |  | ------------------ |  | 
|By: |  |                    |  | 
|    |  | Authorized Officer |  | 

Dated: June 12, 2001

A23

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EXHIBIT B-1    Transfer Certificate

In connection with any transfer of any of the Securities within the period prior to the expiration of the holding period applicable to the sales thereof under
Rule 144(k) under the Securities Act of 1933, as amended (the "Securities Act") (or any successor provision), the undersigned registered owner of
this Security hereby certifies with respect to $            Principal Amount at Maturity of the above-captioned securities presented or surrendered on the date hereof (the
"Surrendered Securities") for registration of transfer, or for exchange or conversion where the securities issuable upon such exchange or conversion are
to be registered in a name other than that of the undersigned registered owner (each such transaction being a "transfer"), that such transfer complies with the restrictive legend set forth on the face
of the Surrendered Securities for the reason checked below:

/ /

A transfer of the Surrendered Securities is made to the Company or any subsidiaries; or/ /

The transfer of the Surrendered Securities complies with Rule 144A under the U.S. Securities Act of 1933, as amended (the "Securities Act"); or/ /

The transfer of the Surrendered Securities is to an institutional accredited investor, as described in Rule 501(a)(1), (2), (3) or (7) of Regulation D under the Securities Act; or/ /

The transfer of the Surrendered Securities is pursuant to an effective registration statement under the Securities Act, or/ /

The transfer of the Surrendered Securities is pursuant to an offshore transaction in accordance with Rule 904 of Regulation S under the Securities Act; or/ /

The transfer of the Surrendered Securities is pursuant to another available exemption from the registration requirement of the Securities Act.


and
unless the box below is checked, the undersigned confirms that, to the undersigned's knowledge, such Securities are not being transferred to an "affiliate" of the Company as
defined in Rule 144 under the Securities Act (an "Affiliate").

/ /

The transferee is an Affiliate of the Company.


|DATE: |  | Signature(s)
|----- |  | ------------

(If the registered owner is a corporation, partnership or
fiduciary, the title of the Person signing on behalf of
such registered owner must be stated.)

B11

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EXHIBIT B-2  Form of Letter to be Delivered by Accredited Investors

Chiron Corporation
4560 Horton Street
Emeryville, CA 94608-2916

Attention:
Chief Financial Officer

State
Street Bank and Trust Company of California, N.A.
633 West 5th St., 12th Fl.
Los Angeles, California 90071

|Attention: | Corporate Trust Administration
(Chiron Corporation Liquid Yield Option Notes due 2031)
|---------- | --------------------------------------------------------------------------------------

Dear
Sirs:

We
are delivering this letter in connection with the proposed transfer to us of $            Principal Amount at Maturity of the Liquid Yield Option Notes due
2031("LYONs") of Chiron Corporation (the "Company"), which are convertible into shares of the Company's
Common Stock, $0.01 par value per share (the "Common Stock").

We
hereby confirm that:



We
understand that the LYONs were originally offered and sold in a transaction not involving any public offering within the United States within the meaning of the Securities Act and
that the LYONs and the shares of Common Stock (the "Securities") issuable upon conversion thereof have not been registered under the Securities Act, and we agree, on our own behalf and on behalf of
each account for which we acquire any LYONs, that if in the future we decide to resell or otherwise transfer such Securities prior to the date (the "Resale Restriction Termination Date") which is two
years after the later of the last day the LYONs of this issue were issued and the last date on which the Company or an

B21

---

affiliate of the Company was the owner of the Security, such Securities may be resold or otherwise transferred only (i) to Chiron Corporation or any subsidiary thereof, or (ii) for as
long as the LYONs are eligible for resale pursuant to Rule 144A, to a person it reasonably believes is a "qualified institutional buyer" (as defined in Rule 144A under the Securities
Act) that purchases for its own account or for the account of a qualified institutional buyer to which notice is given that the transfer is being made in reliance on Rule 144A, or
(iii) to an Institutional Accredited Investor that is acquiring the Security for its own account, or for the account of such Institutional Accredited Investor for investment purposes and
not with a view to, or for offer or sale in connection with, any distribution in violation of the Securities Act, or (iv) pursuant to another available exemption from registration under the
Securities Act (if applicable), or (v) pursuant to a registration statement which has been declared effective under the Securities Act and, in each case, in accordance with any applicable
securities laws of any State of the United States or any other applicable jurisdiction and in accordance with the legends set forth on the Securities. We further agree to provide any person purchasing
any of the Securities other than pursuant to clause (v) above from us a notice advising such purchaser that resales of such securities are restricted as stated herein. We understand that the
trustee or the transfer agent, as the case may be, for the Securities will not be required to accept for registration of transfer any Securities pursuant to (iii) or (iv) above except
upon presentation of evidence satisfactory to the Company that the foregoing restrictions on transfer have been complied with. We further understand that any Securities will be in the form of
definitive physical certificates and that such certificates will bear a legend reflecting the substance of this paragraph other than certificates representing Securities transferred pursuant to
clause (v) above.

We
acknowledge that the Company, others and you will rely upon our confirmations, acknowledgments and agreements set forth herein, and we agree to notify you promptly in writing if
any of our representations or warranties herein ceases to be accurate and complete.

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

| |  | (Name of Purchaser)
| |  | -------------------
| |  | By:                

B22

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EXHIBIT C  Projected Payment Schedule*

|Semi-annual Period Ending |               | Projected Payment per LYON
|------------------------- | ------------- | --------------------------
|December 12, 2001         |               |                          
|                          | June 12, 2002 |                           
|December 12, 2002         |               |                          
|                          | June 12, 2003 |                           
|December 12, 2003         |               |                          
|                          | June 12, 2004 |                           
|December 12, 2004         |               |                          
|                          | June 12, 2005 |                           
|December 12, 2005         |               |                          
|                          | June 12, 2006 |                           
|December 12, 2006         |               |                          
|                          | June 12, 2007 |                           
|December 12, 2007         |               |                          
|                          | June 12, 2008 |                           
|December 12, 2008         |               |                          
|                          | June 12, 2009 |                           
|December 12, 2009         |               |                          
|                          | June 12, 2010 |                           
|December 12, 2010         |               |                          
|                          | June 12, 2011 |                           
|December 12, 2011         |               |                           
|                          | June 12, 2012 |                           
|December 12, 2012         |               | $1.07                     
|                          | June 12, 2013 |                           
|December 12, 2013         |               | $1.15                     
|                          | June 12, 2014 |                           
|December 12, 2014         |               | $1.24                     
|                          | June 12, 2015 |                           
|December 12, 2015         |               | $1.33                     
|                          | June 12, 2016 |                           
|December 12, 2016         |               | $1.43                     
|                          | June 12, 2017 |                           
|December 12, 2017         |               | $1.54                     
|                          | June 12, 2018 |                           
|December 12, 2018         |               | $1.66                     
|                          | June 12, 2019 |                           
|December 12, 2019         |               | $1.79                     
|                          | June 12, 2020 |                           
|December 12, 2020         |               | $1.93                     
|                          | June 12, 2021 |                           
|December 12, 2021         |               | $2.07                     
|                          | June 12, 2022 |                           
|December 12, 2022         |               | $2.23                     
|                          | June 12, 2023 |                           
|December 12, 2023         |               | $2.40                     
|                          | June 12, 2024 |                           

C1

---

|December 12, 2024 |               | $2.59
|----------------- | ------------- | -----
|                  | June 12, 2025 |      
|December 12, 2025 |               | $2.78
|                  | June 12, 2026 |      
|December 12, 2026 |               | $3.00
|                  | June 12, 2027 |      
|December 12, 2027 |               | $3.22
|                  | June 12, 2028 |      
|December 12, 2028 |               | $3.47
|                  | June 12, 2029 |      
|December 12, 2029 |               | $3.74
|                  | June 12, 2030 |      
|December 12, 2030 |               | $4.02
|                  | June 12, 2031 |      

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C2

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