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Exhibit 4.2

ABGENIX, INC.

31/2% CONVERTIBLE SUBORDINATED NOTES DUE 2007

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INDENTURE
DATED AS OF MARCH 4, 2002

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

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TABLE OF CONTENTS

|                                                     |               |    |                                                       | Page
|---------------------------------------------------- | ------------- | -- | ----------------------------------------------------- | ----
|ARTICLE 1 DEFINITIONS AND INCORPORATION BY REFERENCE |               | 1 
|                                                     | SECTION 1.1.  |    | DEFINITIONS                                           |     
|                                                     | SECTION 1.2.  |    | OTHER DEFINITIONS                                     |     
|                                                     | SECTION 1.3.  |    | TRUST INDENTURE ACT PROVISIONS                        |     
|                                                     | SECTION 1.4.  |    | RULES OF CONSTRUCTION                                 |     
|ARTICLE 2 THE SECURITIES                             |               | 8 
|                                                     | SECTION 2.1.  |    | FORM AND DATING                                       |     
|                                                     | SECTION 2.2.  |    | EXECUTION AND AUTHENTICATION                          |     
|                                                     | SECTION 2.3.  |    | REGISTRAR, PAYING AGENT AND CONVERSION AGENT          |     
|                                                     | SECTION 2.4.  |    | PAYING AGENT TO HOLD MONEY IN TRUST                   |     
|                                                     | SECTION 2.5.  |    | SECURITYHOLDER LISTS                                  |     
|                                                     | SECTION 2.6.  |    | TRANSFER AND EXCHANGE                                 |     
|                                                     | SECTION 2.7.  |    | REPLACEMENT SECURITIES                                |     
|                                                     | SECTION 2.8.  |    | OUTSTANDING SECURITIES                                |     
|                                                     | SECTION 2.9.  |    | TREASURY SECURITIES                                   |     
|                                                     | SECTION 2.10. |    | TEMPORARY SECURITIES                                  |     
|                                                     | SECTION 2.11. |    | CANCELLATION                                          |     
|                                                     | SECTION 2.12. |    | LEGEND; ADDITIONAL TRANSFER AND EXCHANGE REQUIREMENTS |     
|                                                     | SECTION 2.13. |    | CUSIP NUMBERS                                         |     
|ARTICLE 3 REDEMPTION AND PURCHASES                   |               | 15
|                                                     | SECTION 3.1.  |    | PROVISIONAL AND OPTIONAL REDEMPTION                   |     
|                                                     | SECTION 3.2.  |    | RIGHT TO REDEEM; NOTICE TO TRUSTEE                    |     
|                                                     | SECTION 3.3.  |    | SELECTION OF SECURITIES TO BE REDEEMED                |     

-i-

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|                     | SECTION 3.4.  |    | NOTICE OF REDEMPTION                                                              |  | 17
|-------------------- | ------------- | -- | --------------------------------------------------------------------------------- |  | --
|                     | SECTION 3.5.  |    | EFFECT OF NOTICE OF REDEMPTION                                                    |  | 17
|                     | SECTION 3.6.  |    | DEPOSIT OF REDEMPTION PRICE                                                       |  | 18
|                     | SECTION 3.7.  |    | SECURITIES REDEEMED IN PART                                                       |  | 18
|                     | SECTION 3.8.  |    | CONVERSION ARRANGEMENT ON CALL FOR REDEMPTION                                     |  | 18
|                     | SECTION 3.9.  |    | PURCHASE OF SECURITIES AT OPTION OF THE HOLDER UPON CHANGE IN CONTROL             |  | 19
|                     | SECTION 3.10. |    | EFFECT OF CHANGE IN CONTROL PURCHASE NOTICE                                       |  | 21
|                     | SECTION 3.11. |    | DEPOSIT OF CHANGE IN CONTROL PURCHASE PRICE                                       |  | 21
|                     | SECTION 3.12. |    | SECURITIES PURCHASED IN PART                                                      |  | 22
|                     | SECTION 3.13. |    | COMPLIANCE WITH SECURITIES LAWS UPON PURCHASE OF SECURITIES                       |  | 22
|                     | SECTION 3.14. |    | REPAYMENT TO THE COMPANY                                                          |  | 22
|ARTICLE 4 CONVERSION |               | 22
|                     | SECTION 4.1.  |    | CONVERSION PRIVILEGE                                                              |  | 22
|                     | SECTION 4.2.  |    | CONVERSION PROCEDURE                                                              |  | 23
|                     | SECTION 4.3.  |    | FRACTIONAL SHARES                                                                 |  | 24
|                     | SECTION 4.4.  |    | TAXES ON CONVERSION                                                               |  | 24
|                     | SECTION 4.5.  |    | COMPANY TO PROVIDE STOCK                                                          |  | 24
|                     | SECTION 4.6.  |    | ADJUSTMENT OF CONVERSION PRICE                                                    |  | 25
|                     | SECTION 4.7.  |    | NO ADJUSTMENT                                                                     |  | 29
|                     | SECTION 4.8.  |    | ADJUSTMENT FOR TAX PURPOSES                                                       |  | 30
|                     | SECTION 4.9.  |    | NOTICE OF ADJUSTMENT                                                              |  | 31
|                     | SECTION 4.10. |    | NOTICE OF CERTAIN TRANSACTIONS                                                    |  | 31
|                     | SECTION 4.11. |    | EFFECT OF RECLASSIFICATION, CONSOLIDATION, MERGER OR SALE ON CONVERSION PRIVILEGE |  | 31
|                     | SECTION 4.12. |    | TRUSTEE'S DISCLAIMER                                                              |  | 32

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|                                                               | SECTION 4.13. |    | VOLUNTARY REDUCTION                                 |  | 32
|-------------------------------------------------------------- | ------------- | -- | --------------------------------------------------- |  | --
|ARTICLE 5 SUBORDINATION                                        |               | 32
|                                                               | SECTION 5.1.  |    | AGREEMENT OF SUBORDINATION                          |  | 32
|                                                               | SECTION 5.2.  |    | PAYMENTS TO HOLDERS                                 |  | 33
|                                                               | SECTION 5.3.  |    | SUBROGATION OF SECURITIES                           |  | 35
|                                                               | SECTION 5.4.  |    | AUTHORIZATION TO EFFECT SUBORDINATION               |  | 36
|                                                               | SECTION 5.5.  |    | NOTICE TO TRUSTEE                                   |  | 36
|                                                               | SECTION 5.6.  |    | TRUSTEE'S RELATION TO SENIOR INDEBTEDNESS           |  | 37
|                                                               | SECTION 5.7.  |    | NO IMPAIRMENT OF SUBORDINATION                      |  | 37
|                                                               | SECTION 5.8.  |    | CERTAIN CONVERSIONS DEEMED PAYMENT                  |  | 37
|                                                               | SECTION 5.9.  |    | ARTICLE APPLICABLE TO PAYING AGENTS                 |  | 37
|                                                               | SECTION 5.10. |    | SENIOR INDEBTEDNESS ENTITLED TO RELY                |  | 38
|ARTICLE 6 COVENANTS                                            |               | 38
|                                                               | SECTION 6.1.  |    | PAYMENT OF SECURITIES                               |  | 38
|                                                               | SECTION 6.2.  |    | SEC REPORTS                                         |  | 38
|                                                               | SECTION 6.3.  |    | COMPLIANCE CERTIFICATES                             |  | 38
|                                                               | SECTION 6.4.  |    | FURTHER INSTRUMENTS AND ACTS                        |  | 39
|                                                               | SECTION 6.5.  |    | MAINTENANCE OF CORPORATE EXISTENCE                  |  | 39
|                                                               | SECTION 6.6.  |    | RULE 144A INFORMATION REQUIREMENT                   |  | 39
|                                                               | SECTION 6.7.  |    | STAY, EXTENSION AND USURY LAWS                      |  | 39
|                                                               | SECTION 6.8.  |    | PAYMENT OF ADDITIONAL INTEREST                      |  | 39
|ARTICLE 7 CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE |               | 40
|                                                               | SECTION 7.1.  |    | COMPANY MAY CONSOLIDATE, ETC, ONLY ON CERTAIN TERMS |  | 40
|                                                               | SECTION 7.2.  |    | SUCCESSOR SUBSTITUTED                               |  | 40

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|ARTICLE 8 DEFAULT AND REMEDIES |               | 41
|------------------------------ | ------------- | --
|                               | SECTION 8.1.  |   
|                               | SECTION 8.2.  |   
|                               | SECTION 8.3.  |   
|                               | SECTION 8.4.  |   
|                               | SECTION 8.5.  |   
|                               | SECTION 8.6.  |   
|                               | SECTION 8.7.  |   
|                               | SECTION 8.8.  |   
|                               | SECTION 8.9.  |   
|                               | SECTION 8.10. |   
|                               | SECTION 8.11. |   
|ARTICLE 9 TRUSTEE              |               | 45
|                               | SECTION 9.1.  |   
|                               | SECTION 9.2.  |   
|                               | SECTION 9.3.  |   
|                               | SECTION 9.4.  |   
|                               | SECTION 9.5.  |   
|                               | SECTION 9.6.  |   
|                               | SECTION 9.7.  |   
|                               | SECTION 9.8.  |   
|                               | SECTION 9.9.  |   
|                               | SECTION 9.10. |   
|                               | SECTION 9.11. |   

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|ARTICLE 10 SATISFACTION AND DISCHARGE OF INDENTURE |                | 49
|-------------------------------------------------- | -------------- | --
|                                                   | SECTION 10.1.  |   
|                                                   | SECTION 10.2.  |   
|                                                   | SECTION 10.3.  |   
|                                                   | SECTION 10.4.  |   
|ARTICLE 11 AMENDMENTS, SUPPLEMENTS AND WAIVERS     |                | 50
|                                                   | SECTION 11.1.  |   
|                                                   | SECTION 11.2.  |   
|                                                   | SECTION 11.3.  |   
|                                                   | SECTION 11.4.  |   
|                                                   | SECTION 11.5.  |   
|                                                   | SECTION 11.6.  |   
|                                                   | SECTION 11.7.  |   
|ARTICLE 12 MISCELLANEOUS                           |                | 53
|                                                   | SECTION 12.1.  |   
|                                                   | SECTION 12.2.  |   
|                                                   | SECTION 12.3.  |   
|                                                   | SECTION 12.4.  |   
|                                                   | SECTION 12.5.  |   
|                                                   | SECTION 12.6.  |   
|                                                   | SECTION 12.7.  |   
|                                                   | SECTION 12.8.  |   
|                                                   | SECTION 12.9.  |   
|                                                   | SECTION 12.10. |   

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| | SECTION 12.11. |  | SUCCESSORS                       |  | 55
| | -------------- |  | -------------------------------- |  | --
| | SECTION 12.12. |  | MULTIPLE COUNTERPARTS            |  | 55
| | SECTION 12.13. |  | SEPARABILITY                     |  | 55
| | SECTION 12.14. |  | TABLE OF CONTENTS, HEADINGS, ETC |  | 55

-vi-

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CROSS-REFERENCE TABLE*

|TIA
SECTION |  | INDENTURE
SECTION    
|----------- |  | ---------------------
|Section     |  | 310(a)(1)            
|            |  | (a)(2)               
|            |  | (a)(3)               
|            |  | (a)(4)               
|            |  | (a)(5)               
|            |  | (b)                  
|            |  | (c)                  
|Section     |  | 311(a)               
|            |  | (b)                  
|            |  | (c)                  
|Section     |  | 312(a)               
|            |  | (b)                  
|            |  | (c)                  
|Section     |  | 313(a)               
|            |  | (b)(1)               
|            |  | (b)(2)               
|            |  | (c)                  
|            |  | (d)                  
|Section     |  | 314(a)               
|            |  | (b)                  
|            |  | (c)(1)               
|            |  | (c)(2)               
|            |  | (c)(3)               
|            |  | (d)                  
|            |  | (e)                  
|            |  | (f)                  
|Section     |  | 315(a)               
|            |  | (b)                  
|            |  | (c)                  
|            |  | (d)                  
|            |  | (e)                  
|Section     |  | 316(a)(last sentence)
|            |  | (a)(1)(A)            
|            |  | (a)(1)(B)            
|            |  | (a)(2)               
|            |  | (b)                  
|            |  | (c)                  
|Section     |  | 317(a)(1)            
|            |  | (a)(2)               
|            |  | (b)                  

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-vii-

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THIS INDENTURE dated as of March 4, 2002 is between Abgenix, Inc., a corporation duly organized under the laws of the State of Delaware (the "Company"), and State Street
Bank and Trust Company of California, N.A., a national banking association organized and existing under the laws of the United States, as Trustee (the "Trustee").

In
consideration of the premises and the purchase of the Securities by the Holders thereof, both parties agree as follows for the benefit of the other and for the equal and ratable
benefit of the registered Holders of the Company's 31/2% Convertible Subordinated Notes due 2007.

ARTICLE 1  DEFINITIONS AND INCORPORATION BY REFERENCE



"Additional Interest" has the meaning specified in paragraph 2 of the Security.

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

"Agent"
means any Registrar, Paying Agent or Conversion Agent.

"Applicable
Procedures" means, with respect to any transfer or exchange of beneficial ownership interests in a Global Security, the rules and procedures of the Depositary, in each case
to the extent applicable to such transfer or exchange.

"Board
of Directors" means either the board of directors of the Company or any committee of the Board of Directors authorized to act for it with respect to this Indenture.

"Business
Day" means each day that is not a Legal Holiday.

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

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

"Certificated
Security" means a Security that is in substantially the form attached hereto asExhibit Aand that does not include
the information or the schedule called for by footnotes 1, 3 and 4 thereof.

"Common
Stock" means the common stock of the Company, $0.0001 par value, as it exists on the date of this Indenture and any shares of any class or classes of capital stock of the Company
resulting from any reclassification or reclassifications thereof and which have no preference in respect of dividends or of amounts payable in the event of any voluntary or involuntary liquidation,
dissolution or winding-up of the Company and which are not subject to redemption by the Company;provided, however,that if at any time
there shall be more than one such resulting class, the shares of each such class then so issuable on conversion of Securities shall be substantially in the proportion which the total number of shares
of such class resulting from all such reclassifications bears to the total number of shares of all such classes resulting from all such reclassifications.

1

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"Company"
means the party named as such in the first paragraph of this Indenture until a successor replaces it pursuant to the applicable provisions of this Indenture, and thereafter
"Company" shall mean such successor Company.

"Corporate
Trust Office" means the office of the Trustee at which at any particular time the trust created by this Indenture shall be administered which office at the date of the
execution of this Indenture is located at 633 West Fifth Street, 12th Floor, Los Angeles, California 90071, Attention: Corporate Trust Administration
(Abgenix, Inc.31/2% Convertible Subordinated Notes Due 2007) or at any other time at such other address as the Trustee may designate from time to time by notice to
the Company.

"Default"
or "default" means, when used with respect to the Securities, any event which is or, after notice or passage of time or both, would be an Event of Default.

"Designated
Senior Indebtedness" means any particular Senior Indebtedness of the Company in which the instrument creating or evidencing the same or the assumption or guarantee thereof
(or any related agreements or documents to which the Company is a party) expressly provides that such Senior Indebtedness shall be "Designated Senior Indebtedness" for purposes of this Indenture
(provided thatsuch instrument, agreement or other document creating or evidencing the indebtedness may place limitations and conditions on the right of
such Senior Indebtedness to exercise the rights of Designated Senior Indebtedness). If any payment made to any holder of any Designated Senior Indebtedness or its Representative with respect to such
Designated Senior Indebtedness is rescinded or must otherwise be returned by such holder or Representative upon the insolvency, bankruptcy or reorganization of the Company or otherwise, the reinstated
Indebtedness of the Company arising as a result of such rescission or return shall constitute Designated Senior Indebtedness effective as of the date of such rescission or return.

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

"Final
Maturity Date" means March 15, 2007.

"GAAP"
means generally accepted accounting principles in the United States of America as in effect as of the date of this Indenture, including those set forth in (1) the opinions
and pronouncements of the Accounting Principles Board of the American Institute of Certified Public Accountants, (2) the statements and pronouncements of the Financial Accounting Standards
Board, (3) such other statements by such other entity as approved by a significant segment of the accounting profession and (4) the rules and regulations of the SEC governing the
inclusion of financial statements (including pro forma financial statements) in registration statements filed under the Securities Act and periodic reports required to be filed pursuant to
Section 13 of the Exchange Act, including opinions and pronouncements in staff accounting bulletins and similar written statements from the accounting staff of the SEC.

"Global
Security" means a permanent Global Security that is in substantially the form attached hereto asExhibit Aand that
includes the information and schedule called for by footnotes 1, 3 and 4 thereof
and which is deposited with the Depositary or its custodian and registered in the name of the Depositary or its nominee.

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

"Indebtedness"
means, with respect to any Person, without duplication, (a) all indebtedness, obligations and other liabilities (contingent or otherwise) of such Person
(i) for borrowed money (including obligations of such Person in respect of overdrafts, foreign exchange contracts, currency exchange agreements, interest rate protection agreements, and any
loans or advances from banks,

2

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whether or not evidenced by notes or similar instruments) or (ii) evidenced by credit or loan agreements, bonds, debentures, notes or similar instruments (whether or not the recourse of the
lender is to the whole of the assets of such Person or to only a portion thereof) (other than any accounts payable or other accrued current liability or obligation incurred in the ordinary course of
business in connection with the obtaining of materials or services), (b) all reimbursement obligations and other liabilities (contingent or otherwise) of such Person with respect to letters of
credit, bank guarantees or bankers' acceptances, (c) all obligations and liabilities (contingent or otherwise) of such Person (i) in respect of (A) leases of such Person required,
in conformity with GAAP, to be accounted for as capitalized lease obligations on the balance sheet of such Person (as determined by the Company), and (B) ground leases the Company may enter
into the future with respect to the Company's facilities in Fremont, California, or (ii) under any lease or related document (including a purchase agreement, conditional sale or other title
retention agreement) in connection with the lease of real property or improvement thereon (or any personal property included as part of any such lease) which provides that such Person is contractually
obligated to purchase or cause a third party to purchase the leased property or pay an agreed upon residual value of the leased property to the lessor (whether or not such lease transaction is
characterized as an operating lease or a capitalized lease in accordance with GAAP), (d) all obligations (contingent or otherwise) of such Person with respect to any interest rate or other
swap, cap, floor or collar agreement, hedge agreement, forward contract, or other similar instrument or agreement or foreign currency hedge, exchange, purchase or similar instrument or agreement;
(e) all direct or indirect guaranties, agreements to be jointly liable or similar agreements by such Person in respect of, and obligations or liabilities of such Person to purchase or otherwise
acquire or otherwise assure a creditor against loss in respect of, indebtedness, obligations or liabilities of another Person of the kind described in clauses (a) through (d), and
(f) any and all deferrals, renewals, extensions, refinancings and refundings of, or amendments, modifications or supplements to, any indebtedness, obligation or liability of the kind described
in clauses (a) through (e).

"Indenture"
means this Indenture as amended or supplemented from time to time pursuant to the terms of this Indenture.

"Initial
Purchasers" means Credit Suisse First Boston Corporation, Banc of America Securities LLC and Robertson Stephens, Inc.

"Issuance
Date" means the date on which the Securities are first authenticated and issued.

"Officer"
means the Chairman or any Co-Chairman of the Board, any Vice Chairman of the Board, the Chief Executive Officer, the President, any Vice President, the Chief
Financial Officer, the Controller, the Secretary or any Assistant Controller or Assistant Secretary of the Company.

"Officers'
Certificate" means a certificate signed by two Officers;provided, however,that for purposes of Sections 4.11 and 6.3,
"Officers' Certificate" means a certificate signed by the principal executive officer, principal financial officer or principal accounting officer of the Company and by one other Officer.

"Opinion
of Counsel" means a written opinion from legal counsel. The counsel may be an employee of or counsel to the Company or the Trustee.

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

"Principal"
or "principal" of a debt security, including the Securities, means the principal of the security plus, when appropriate, the premium, if any, on the security.

"Redemption
Date" when used with respect to any Security to be redeemed, means the date fixed for such redemption pursuant to this Indenture.

3

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"Redemption
Price" when used with respect to any Security to be redeemed, means the price fixed for such redemption pursuant to this Indenture, as set forth in the form of Security
annexed asExhibit Ahereto.

"Registration
Rights Agreement" means the Registration Rights Agreement dated, as of March 4, 2002, between the Company and the Initial Purchasers.

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

"Rule 144"
means Rule 144 under the Securities Act or any successor to such Rule.

"Rule 144A"
means Rule 144A under the Securities Act or any successor to such Rule.

"SEC"
means the Securities and Exchange Commission.

"Securities"
means the 31/2% Convertible Subordinated Notes due 2007 or any of them (each, a "Security"), as amended or supplemented from time to time, that are issued
under this Indenture.

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

"Securities
Custodian" means the Trustee, as custodian with respect to the Securities in global form, or any successor thereto.

"Senior
Indebtedness" means the principal of, premium, if any, interest (including all interest accruing subsequent to the commencement of any bankruptcy or similar proceeding, whether
or not a claim for post-petition interest is allowed as a claim in any such proceeding) and rent payable on or in connection with, and all fees, costs, expenses and other amounts accrued
or due on or in connection with, Indebtedness of the Company, whether outstanding on the date of this Indenture or thereafter created, incurred, assumed, guaranteed or in effect guaranteed by the
Company (including all deferrals, renewals, extensions or refundings of, or amendments, modifications or supplements to, the foregoing), unless in the case of any particular Indebtedness the
instrument creating or evidencing the same or the assumption or guarantee thereof expressly provides that such Indebtedness shall not be senior in right of payment to the Securities or expressly
provides that such Indebtedness is "pari passu" or "junior" to the Securities. Notwithstanding the foregoing, the term Senior Indebtedness shall not include (i) any Indebtedness of the Company
to any Subsidiary of the Company (other than Indebtedness of the Company to such Subsidiary arising by reason of guarantees by the Company of Indebtedness of such Subsidiary to a Person that is not a
Subsidiary of the Company); (ii) the Securities; or (iii) Indebtedness of or amounts owed by the Company for compensation to employees, or for goods or materials purchased in the
ordinary course of business, or for services. If any payment made to any holder of any Senior Indebtedness or its Representative with respect to such Senior Indebtedness is rescinded or
must otherwise be returned by such holder or Representative upon the insolvency, bankruptcy or reorganization of the Company or otherwise, the reinstated Indebtedness of the Company arising as a
result of such rescission or return shall constitute Senior Indebtedness effective as of the date of such rescission or return.

"Significant
Subsidiary" means, in respect of any Person, a Subsidiary of such Person that would constitute a "significant subsidiary" as such term is defined under
Rule 1-02 of Regulation S-X under the Securities Act and the Exchange Act.

4

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

"TIA"
means the Trust Indenture Act of 1939, as amended, and the rules and regulations thereunder as in effect on the date of this Indenture, except as provided in Section 11.3,
and except to the extent any amendment to the Trust Indenture Act expressly provides for application of the Trust Indenture Act as in effect on another date.

"Trading
Day" means, with respect to any security, each Monday, Tuesday, Wednesday, Thursday and Friday, other than any day on which securities are not generally traded on the principal
exchange or market in which such security is traded.

"Transfer
Restricted Global Security" means a Global Security that is a Transfer Restricted Security.

"Transfer
Restricted Security" means a Security required to bear the restricted legend set forth in the form of Security set forth inExhibit Aof this Indenture.

"Trustee"
means the party named as such in the first paragraph of this Indenture until a successor replaces it in accordance with the provisions of this Indenture, and thereafter means
the successor.

"Trust
Officer" means, with respect to the Trustee, any officer assigned to the Corporate Trust Office, and also, with respect to a particular matter, any other officer to whom such
matter is referred because of such officer's knowledge of and familiarity with the particular subject.

"Unrestricted
Certificated Security" means a Certificated Security that is not a Transfer Restricted Security.

"Unrestricted
Global Security" means a Global Security that is not a Transfer Restricted Security.

"Vice
President" when used with respect to the Company or the Trustee, means any vice president, whether or not designated by a number or a word or words added before or after the title
"vice president."

"Voting
Stock" of a Person means all classes of Capital Stock or other interests (including partnership interests) of such Person then outstanding and normally entitled (without regard
to the occurrence of any contingency) to vote in the election of directors, managers or trustees thereof.



|Term                                |  | Defined in Section |    
|----------------------------------- |  | ------------------ | ---
|"Agent Members"                     |  | 2.1                | (b)
|"Bankruptcy Law"                    |  | 8.1                |    
|"Change in Control"                 |  | 3.9                | (a)
|"Change in Control Purchase Date"   |  | 3.9                | (c)
|"Change in Control Purchase Notice" |  | 3.9                | (f)
|"Change in Control Purchase Price"  |  | 3.9                | (a)
|"Closing Price"                     |  | 4.6                | (d)
|"Company Order"                     |  | 2.2                |    
|"Conversion Agent"                  |  | 2.3                |    
|"Conversion Date"                   |  | 4.2                |    

5

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|"Conversion Price"                  |  | 4.6  |    
|----------------------------------- |  | ---- | ---
|"Current Market Price"              |  | 4.6  | (d)
|"Custodian"                         |  | 8.1  |    
|"DTC"                               |  | 2.1  |    
|"Depositary"                        |  | 2.1  |    
|"Determination Date"                |  | 4.6  | (c)
|"Event of Default"                  |  | 8.1  |    
|"Expiration Date"                   |  | 4.6  | (c)
|"Expiration Time"                   |  | 4.6  | (c)
|"Legal Holiday"                     |  | 12.7 |    
|"Legend"                            |  | 2.12 |    
|"Make-Whole Payment"                |  | 3.1  | (a)
|"NNM"                               |  | 4.6  | (d)
|"Paying Agent"                      |  | 2.3  |    
|"Payment Blockage Notice"           |  | 5.2  |    
|"Primary Registrar"                 |  | 2.3  |    
|"Provisional Redemption             |  | 3.1  | (a)
|"Provisional Redemption Date        |  | 3.1  | (a)
|"Provisional Redemption Notice Date |  | 3.1  | (a)
|"Provisional Redemption Price       |  | 3.1  | (a)
|"Purchase Agreement"                |  | 2.1  |    
|"Purchase Offer"                    |  | 3.9  | (a)
|"Purchased Shares"                  |  | 4.6  | (c)
|"QIB"                               |  | 2.1  |    
|"Registrar"                         |  | 2.3  |    
|"Rights Plan"                       |  | 4.6  | (c)
|"Triggering Distribution"           |  | 4.6  | (c)
|"Trigger Event"                     |  | 4.6  | (c)
|"Unissued Shares"                   |  | 3.9  | (a)



Whenever this Indenture refers to a provision of the TIA, that provision is incorporated by reference in and made a part of this Indenture. The Indenture shall
also include those provisions of the TIA required to be included herein by the provisions of the Trust Indenture Reform Act of 1990. The following TIA terms used in this Indenture have the following
meanings:

"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; and "obligor" on the indenture securities means the Company or any other obligor on the Securities.

All
other terms used in this Indenture that are defined in the TIA, defined by TIA reference to another statute or defined by any SEC rule and not otherwise defined herein have the
meanings assigned to them therein.

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Unless the context otherwise requires:



7

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ARTICLE 2  THE SECURITIES



The Securities and the Trustee's certificate of authentication shall be substantially in the respective forms set forth in Exhibit A,
which Exhibit is incorporated in and made part of this Indenture. The Securities may have notations, legends or endorsements required
by law, stock exchange rule or usage. 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. The
Securities are being offered and sold by the Company pursuant to a Purchase Agreement, dated February 27, 2002 (the "Purchase Agreement"), between the Company and the Initial Purchasers, in
transactions exempt from, or not subject to, the registration requirements of the Securities Act.

(a)Restricted Global Securities. All of the Securities are initially being offered and sold to qualified institutional
buyers as defined in Rule 144A (collectively, "QIBs" or individually, each a "QIB") in reliance on Rule 144A under the Securities Act and to certain non-U.S. persons under
Regulation S under the Securities Act, shall be issued initially in the form of one or more Restricted Global Securities, which shall be deposited on behalf of the purchasers of the Securities
represented thereby with the Trustee, at its Corporate Trust Office, as custodian for the depositary, The Depository Trust Company ("DTC") (such depositary, or any successor thereto, being hereinafter
referred to as the "Depositary"), and registered in the name of its nominee, Cede & Co., duly executed by the Company and authenticated by the Trustee as hereinafter provided. The aggregate
principal amount of the Restricted Global Securities may from time to time be increased or decreased by adjustments made on the records of the Securities Custodian as hereinafter provided, subject in
each case to compliance with the Applicable Procedures.

(b)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 amount of outstanding Securities from time to time endorsed thereon and that the aggregate amount of outstanding
Securities represented thereby may from time to time be reduced or increased, as appropriate, to reflect exchanges, redemptions, purchases or conversions of such Securities. Any
adjustment of the aggregate principal amount of a Global Security to reflect the amount of any increase or decrease in the amount 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.

Members
of, or participants in, the Depositary ("Agent Members") shall have no rights under this Indenture with respect to any Global Security held on their behalf by the Depositary or
under the Global Security, and the Depositary (including, for this purpose, its nominee) may be treated by the Company, the Trustee and any agent of the Company or the Trustee as the absolute owner
and Holder of such Global Security for all purposes whatsoever. Notwithstanding the foregoing, nothing herein shall (A) prevent the Company, the Trustee or any agent of the Company or the
Trustee from giving effect to any written certification, proxy or other authorization furnished by the Depositary or (B) impair, as between the Depositary and its Agent Members, the operation
of customary practices governing the exercise of the rights of a Holder of any Security.

(c)Book Entry Provisions. The Company shall execute and the Trustee shall, in accordance with this Section 2.1(c),
authenticate and deliver initially one or more Global Securities that (i) shall be registered in the name of the Depositary, (ii) shall be delivered by the Trustee to the Depositary or

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pursuant to the Depositary's instructions and (iii) shall bear legends substantially to the following effect:

"UNLESS
THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE
ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF 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. THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS
REGISTERED IN THE NAME OF A DEPOSITARY OR A NOMINEE THEREOF. THIS SECURITY IS EXCHANGEABLE FOR SECURITIES REGISTERED IN THE NAME OF A PERSON OTHER THAN THE DEPOSITARY OR ITS NOMINEE ONLY IN THE
LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE AND, UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR SECURITIES IN DEFINITIVE FORM, THIS SECURITY MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY
THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR
DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY."



An Officer shall sign the Securities for the Company by manual or facsimile signature attested by the manual or facsimile signature of the Secretary or an
Assistant Secretary of the Company. Typographic and other minor errors or defects in any such facsimile signature shall not affect the validity or enforceability of any Security which has been
authenticated and delivered by the Trustee.

If
an Officer whose signature is on a Security no longer holds that office at the time the Trustee authenticates the Security, the Security shall be valid nevertheless.

A
Security shall not be valid until an authorized signatory of the Trustee manually signs the certificate of authentication on the Security. The signature shall be conclusive evidence
that the Security has been authenticated under this Indenture.

The
Trustee shall authenticate and make available for delivery Securities for original issue in the aggregate principal amount of up to $250,000,000 upon receipt of a written order or
orders of the Company signed by two Officers of the Company (a "Company Order"). The Company Order shall specify the amount of Securities to be authenticated, shall provide that all such Securities
will be represented by a Restricted Global Security and the date on which each original issue of Securities is to be authenticated. The aggregate principal amount of Securities outstanding at any time
may not exceed $250,000,000 except as provided in Section 2.7.

The
Trustee shall act as the initial authenticating agent. Thereafter, the Trustee may appoint an authenticating agent acceptable to the Company to authenticate Securities. An
authenticating agent may authenticate Securities whenever the Trustee may do so. Each reference in this Indenture to authentication by the Trustee includes authentication by such agent. An
authenticating agent shall have the same rights as an Agent to deal with the Company or an Affiliate of the Company.

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The
Securities shall be issuable only in registered form without coupons and only in denominations of $1,000 principal amount and any integral multiple thereof.



The Company shall maintain one or more offices or agencies where Securities may be presented for registration of transfer or for exchange (each, a "Registrar"),
one or more offices or agencies where Securities may be presented for payment (each, a "Paying Agent"), one or more offices or agencies where Securities may be presented for conversion (each, a
"Conversion Agent") and one or more offices or agencies where notices and demands to or upon the Company in respect of the Securities and this Indenture may be served. The Company will at all times
maintain a Paying Agent, Conversion Agent, Registrar and an office or agency where notices and demands to or upon the Company in respect of the Securities and this Indenture may be served in the
Borough of Manhattan, The City of New York. One of the Registrars (the "Primary Registrar") shall keep a register of the Securities and of their transfer and exchange.

The
Company shall enter into an appropriate agency agreement with any Agent not a party to this Indenture. 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 Agent not a party to this Indenture. If the Company fails to maintain a Registrar, Paying Agent, Conversion Agent or
agent for service of notices and demands in any place required by this Indenture, or fails to give the foregoing notice, the Trustee shall act as such. The Company or any Affiliate of the Company may
act as Paying Agent (except for the purposes of Section 6.1 and Article 10).

The
Company hereby initially designates the Trustee as Paying Agent, Registrar, Custodian and Conversion Agent, and each of the Corporate Trust Office of the Trustee and the office or
agency of the Trustee in the Borough of Manhattan, The City of New York (which shall initially be State Street Bank and Trust Company, N.A., an Affiliate of the Trustee, as agent of the Trustee
located at 61 Broadway, New York, New York 10006, Attention: Corporate Trust Administration (Abgenix, Inc.31/2% Convertible Subordinated Notes due 2007)), one such
office or agency of the Company for each of the aforesaid purposes.



Prior to 11:00 a.m., New York City time, on each due date of the principal of or interest, if any, on any Securities, the Company shall deposit with a
Paying Agent a sum sufficient to pay such principal or interest, if any, so becoming due. Subject to Section 5.2, a Paying Agent shall hold in trust for the benefit of Securityholders or the
Trustee all money held by the Paying Agent for the payment of principal of or interest, if any, on the Securities, and shall notify the Trustee of any default by the Company (or any other obligor on
the Securities) in making any such payment. If the Company or an Affiliate of the Company acts as Paying Agent, it shall, before 11:00 a.m., New York City time, on each due date of the
principal of or interest on any Securities, segregate the money and hold it as a separate trust fund. The Company at any time may require a Paying Agent to pay all money held by it to the Trustee, and
the Trustee may at any time during the continuance of any default, upon written request to a Paying Agent, require such Paying Agent to pay forthwith to the Trustee all sums so held in trust
by such Paying Agent. Upon doing so, the Paying Agent (other than the Company) shall have no further liability for the money.



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 Primary Registrar, the Company shall furnish to the Trustee on or before each semiannual interest payment

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date, 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.



(a)  Subject
to compliance with any applicable additional requirements contained in Section 2.12, when a Security is presented to a Registrar with a request to
register a transfer thereof or to exchange such Security for an equal principal amount of Securities of other authorized denominations, the Registrar shall register the transfer or make the exchange
as requested;provided, however, that every Security presented or surrendered for registration of transfer or exchange shall be duly endorsed or
accompanied by an assignment form and, if applicable, a transfer certificate each in the form included inExhibit A, and in form satisfactory to
the Registrar duly executed by the Holder thereof or its attorney duly authorized in writing. To permit registration of transfers and exchanges, upon surrender of any Security for registration of
transfer or exchange at an office or agency maintained pursuant to Section 2.3, the Company shall execute and the Trustee shall authenticate Securities of a like aggregate principal amount at
the Registrar's request. Any exchange or transfer shall be without charge, except that the Company or the Registrar may require payment of a sum sufficient to cover any tax or other governmental
charge that may be imposed in relation thereto, andprovided, thatthis sentence shall not apply to any exchange pursuant to Section 2.10,
2.12(a), 3.6, 3.11, 4.2 (last paragraph) or 11.5.

Neither
the Company, any Registrar nor the Trustee shall be required to exchange or register a transfer of (i) any Securities for a period of 15 days next preceding any
mailing of a notice of Securities to be redeemed, (ii) any Securities or portions thereof selected or called for redemption (except, in the case of redemption of a Security in part, the portion
thereof not to be redeemed) or (iii) any Securities or portions thereof in respect of which a Change in Control Purchase Notice has been delivered and not withdrawn by the Holder thereof
(except, in the case of the purchase of a Security in part, the portion thereof not to be purchased).

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

(b)  Any
Registrar appointed pursuant to Section 2.3 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 transfer or exchange of Securities.

(c)  Each
Holder of a Security agrees to indemnify the Company and the Trustee against any liability that may result from the transfer, exchange or assignment of such
Holder's Security in violation of any provision of this Indenture and/or applicable United States federal or state securities law.

The
Trustee 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 Agent Members or other 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.



If any mutilated Security is surrendered to the Company, a Registrar or the Trustee, or the Company, a Registrar and the Trustee receive evidence to their
satisfaction of the destruction, loss or theft of any Security, and there is delivered to the Company, the applicable Registrar and the Trustee such security or indemnity as will be required by them
to save each of them harmless, then, in the

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absence of notice to the Company, such Registrar or the Trustee that such Security has been acquired by a bona fide purchaser, the Company shall execute, and upon its written request the Trustee
shall authenticate and deliver, in exchange for any such mutilated Security or in lieu of any such destroyed, lost or stolen Security, a new Security of like tenor and principal amount, bearing a
number not contemporaneously outstanding.

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

Upon
the issuance of any new Securities under this Section 2.7, 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 reasonable expenses (including the reasonable fees and expenses of the Trustee or the Registrar) in connection therewith.

Every
new Security issued pursuant to this Section 2.7 in lieu of any mutilated, destroyed, lost or stolen Security shall constitute an original additional contractual obligation
of the Company, whether or not the mutilated, 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 2.7 are (to the extent lawful) 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.



Securities outstanding at any time are all Securities authenticated by the Trustee, except for those canceled by it, those converted pursuant to
Article IV, those delivered to it for cancellation or surrendered for transfer or exchange and those described in this Section 2.8 as not outstanding.

If
a Security is replaced pursuant to Section 2.7, it ceases to be outstanding unless the Company receives proof satisfactory to it that the replaced Security is held by a bona
fide purchaser.

If
a Paying Agent (other than the Company or an Affiliate of the Company) holds on a Redemption Date, a Change in Control Purchase Date or the Final Maturity Date money sufficient to pay
the principal of (including premium, if any) and accrued interest on Securities (or portions thereof) payable on that date, then on and after such Redemption Date, Change in Control Purchase Date or
the final Maturity Date, as the case may be, such Securities (or portions thereof, as the case may be) shall cease to be outstanding and interest on them shall cease to accrue; provided, that if such
Securities are to be redeemed, notice of such redemption has been duly given pursuant to this Indenture or provision therefore satisfactory to the Trustee has been made.

Subject
to the restrictions contained in Section 2.9, a Security does not cease to be outstanding because the Company or an Affiliate of the Company holds the Security.



In determining whether the Holders of the required principal amount of Securities have concurred in any notice, direction, waiver or consent, Securities owned by
the Company or any other obligor on the Securities or by any Affiliate of the Company or of such other obligor shall be disregarded, except that, for purposes of determining whether the Trustee shall
be protected in relying on any such notice, direction, waiver or consent, only Securities which a Trust Officer of the Trustee actually knows are so owned shall be so disregarded. Securities so owned
which have been pledged in good faith shall not be

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disregarded if the pledgee establishes to the satisfaction of the Trustee the pledgee's right so to act with respect to the Securities and that the pledgee is not the Company or any other obligor on
the Securities or any Affiliate of the Company or of such other obligor.



Until definitive Securities are ready for delivery, the Company may prepare and execute, and, upon receipt of a Company Order, the Trustee shall authenticate and
deliver, temporary Securities. Temporary Securities shall be substantially in the form of definitive Securities but may have variations that the Company with the consent of the Trustee considers
appropriate for temporary Securities. Without unreasonable delay, the Company shall prepare and the Trustee shall authenticate and deliver definitive Securities in exchange for temporary Securities.



The Company at any time may deliver Securities to the Trustee for cancellation. The Registrar, the Paying Agent and the Conversion Agent shall forward to the
Trustee or its agent any Securities surrendered to them for transfer, exchange, redemption, payment or conversion. The Trustee and no one else shall cancel, in accordance with its standard procedures,
all Securities surrendered for transfer, exchange, redemption, payment, conversion or cancellation and shall deliver the canceled Securities to the Company. All Securities which are redeemed,
purchased or otherwise acquired by the Company or any of its Subsidiaries prior to the Final Maturity Date shall be delivered to the Trustee for cancellation, and the Company may not hold or resell
such Securities or issue any new Securities to replace any such Securities or any Securities that any Holder has converted pursuant to Article 4. Without limitation to the foregoing, any
Securities acquired by any investment bankers or other purchasers pursuant to Section 3.7 shall be surrendered for conversion and thereafter cancelled, and may not be reoffered, sold or
otherwise transferred.



(a)  If
Securities are issued upon the transfer, exchange or replacement of Securities subject to restrictions on transfer and bearing the legends set forth on the forms of
Securities attached hereto asExhibit A(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 if requested by the Company or such Registrar, 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;provided thatno such evidence need be supplied in connection with the sale of such Security
pursuant to a registration statement that is effective at the time of such sale. Upon (i) provision of such satisfactory evidence if requested, 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 removed from the face of a Security and the Security is subsequently held by an Affiliate of the Company, the Legend
shall be reinstated.

(b)  A
Global Security may not be transferred, in whole or in part, to any Person other than the Depositary or a nominee or any successor thereof, and no such transfer to any
such other Person may be registered;provided thatthe foregoing shall not prohibit any transfer of a Security that is issued in exchange for a Global
Security but is not itself a Global Security. No transfer of a Security to any Person shall be effective under this Indenture or the Securities unless and until such Security has been registered in
the name of such Person. Notwithstanding any other provisions of this Indenture or the

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Securities, transfers of a Global Security, in whole or in part, shall be made only in accordance with this Section 2.12.

(c)  Subject
to the succeeding paragraph, every Security shall be subject to the restrictions on transfer provided in the Legend other than a Restricted Global Security.
Whenever any Transfer Restricted Security other than a Restricted Global 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, 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.

(d)  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, if requested, an opinion of counsel
reasonably acceptable to the Company, addressed to the Company 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, 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 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.

(e)  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.

(f)    The
provisions of clauses (i), (ii), (iii) and (iv) below shall apply only to Global Securities:



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The Company in issuing the Securities may use one or more "CUSIP" numbers (if then generally in use), and, if so, the Trustee shall use "CUSIP" numbers in notices
of redemption or purchase as a convenience to Holders;provided thatany 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 or purchase and that reliance may be placed only on the other identification numbers printed on the
Securities, and any such redemption or purchase 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 3  REDEMPTION AND PURCHASES



(a)  The
Securities may be redeemed at the election of the Company, as a whole or in part from time to time, at any time prior to March 20, 2005 (a "Provisional
Redemption"), upon at least 20 and not more than 60 days' notice by mail to the Holders of the Securities at a redemption price equal to $1,000 per $1,000 principal amount of the Securities
redeemed plus accrued and unpaid interest, if any (such amount, together with the Make-Whole Payment described below, the "Provisional Redemption Price"), to but excluding the date of
redemption (the "Provisional Redemption Date") if (1) the

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Closing Price of the Common Stock has exceeded 150% of the then applicable Conversion Price for at least 20 Trading Days within a period of any 30 consecutive Trading Days ending on the Trading Day
prior to the date of mailing of the notice of Provisional Redemption (the "Provisional Redemption Notice Date"), and (2) a shelf registration statement covering resales of the Securities and
the Common Stock issuable upon conversion thereof is effective and available for use in accordance with the Registration Rights Agreement and is expected to remain effective and available for use for
the 30 days following the Provisional Redemption Date unless registration is no longer required.

Upon
any such Provisional Redemption, the Company, shall make an additional payment, which at its option shall be made either in cash or Common Stock or a combination of cash and Common
Stock (the "Make-Whole Payment") with respect to the Securities called for redemption to holders on the Provisional Redemption Notice Date in an amount equal to $105.00 per $1,000
principal amount of the Securities, less the amount of any interest actually paid (including, if the Provisional Redemption Date occurs after a record date but before an interest payment date, any
interest paid or to be paid in connection with such interest payment date) on such Securities prior to the Provisional Redemption Date. Payments made in Common Stock will be valued at 97% of the
average Closing Price of Common Stock for the five Trading Days ending on the day prior to the Redemption Date. The Company shall make the Make-Whole Payment on all Securities called for
Provisional Redemption, including those Securities converted into Common Stock between the Provisional Redemption Notice Date and the Provisional Redemption Date.

(b)  Except
as set forth in clause (a) of this Section 3.1, the Company shall not have the option to redeem the Notes pursuant to this Section 3.1 prior
to March 20, 2005. Thereafter, the Company shall have the option to redeem the Securities, in whole or in part, at the redemption prices (expressed as percentages
of principal amount) set forth below plus accrued and unpaid interest and Additional Interest thereon, if any, to the applicable Redemption Date, if redeemed during the periods set forth below:

Period

PercentageBeginning March 20, 2005 through March 14, 2006

100.875%Beginning March 15, 2006 and thereafter

100.000%


(c)  Any
redemption pursuant to this Section 3.1 shall be made pursuant to the provisions of Section 3.2 through 3.14 hereof.



If the Company elects to redeem Securities pursuant to Section 3.1 and paragraph 6 of the Securities, it shall notify the Trustee at least
45 days prior to the Redemption Date as fixed by the Company (unless a shorter notice shall be satisfactory to the Trustee) of the Redemption Date and the principal amount of Securities to be
redeemed. If fewer than all of the Securities are to be redeemed, the record date relating to such redemption shall be selected by the Company and given to the Trustee, which record date shall not be
less than ten days after the date of notice to the Trustee.



If less than all of the Securities are to be redeemed, unless the procedures of the Depositary provide otherwise, the Trustee shall, at least 20 days but
not more than 60 days prior to the Redemption Date, select the Securities to be redeemed. The Trustee shall make the selection from the Securities outstanding and not previously called for
redemption, by lot, or in its discretion, on a pro rata basis. Securities in denominations of $1,000 may only be redeemed in whole. The Trustee may select for redemption portions (equal to $1,000 or
any integral multiple thereof) of the principal of

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Securities that have denominations larger than $1,000. Provisions of this Indenture that apply to Securities called for redemption also apply to portions of Securities called for redemption.

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 to be the portion selected for redemption. Securities which have been converted during a selection of Securities to be redeemed shall be treated by the Trustee
as outstanding for the purpose of such selection.



At least 20 days but not more than 60 days before a Redemption Date, the Company shall mail or cause to be mailed a notice of redemption to each
Holder of Securities to be redeemed at such Holder's address as it appears on the Primary Registrar's books.

The
notice shall identify the Securities (including CUSIP numbers) to be redeemed and shall state:



If
any of the Securities to be redeemed is in the form of a Global Security, then the Company shall modify such notice to the extent necessary to accord with the procedures of the
Depositary applicable to redemptions. At the Company's written request to the Trustee at least 25 days prior to the Redemption Date, which request shall (i) be irrevocable once given and
(ii) set forth all relevant information required by clauses (1) through (8) of the preceding paragraph, the Trustee shall give the notice of redemption in the Company's name and
at the Company's expense.



Once notice of redemption is mailed, Securities called for redemption become due and payable on the Redemption Date and at the Redemption Price stated in the
notice, together with accrued interest, if any, except for Securities that are converted in accordance with the provisions of Article 4. Upon presentation and surrender to a Paying Agent,
Securities called for redemption shall be paid at the Redemption Price, plus accrued interest up to but not including the Redemption Date;provided thatif

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the Redemption Date falls after an interest payment record date and on or before an interest payment date, then the interest will be payable to the Holders in whose name the Securities are registered
at the close of business on the interest payment record date.



Prior to 11:00 a.m. New York City time, on the Redemption Date, the Company shall deposit with a Paying Agent (or, if the Company acts as Paying Agent,
shall segregate and hold in trust) an amount of money (in immediately available funds if deposited on such Redemption Date) sufficient to pay the Redemption Price of and accrued interest on all
Securities to be redeemed on that date, other than Securities or portions thereof called for redemption on that date which 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 the
conversion of Securities pursuant to Article 4 or, if such money is then held by the Company in trust and is not required for such purpose, it shall be discharged from the trust.



Upon presentation and 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 equal in principal amount to the unredeemed portion of the Security surrendered.



In connection with any redemption of Securities, the Company may arrange for the purchase and conversion of any Securities called for redemption by an agreement
with one or more investment bankers or other purchasers to purchase such Securities by paying to a Paying Agent (other than the Company or any of its Affiliates) in trust for the Holders, on or before
11:00 a.m. New York City time on the Redemption Date, an amount that, together with any amounts deposited with such Paying Agent by the Company for the redemption of such Securities, is not
less than the Redemption Price, together with interest accrued to, but not including, the Redemption Date, of such Securities. Notwithstanding anything to the contrary contained in this
Article 3, the obligation of the Company to pay the Redemption Price of such Securities, including all accrued interest, shall be deemed to be satisfied and discharged to the extent such amount
is so paid by such purchasers;provided, however,that nothing in this Section 3.7 shall relieve the Company of its obligation to pay the
Redemption Price, plus accrued interest to but excluding the relevant Redemption Date, on Securities called for redemption. If such an agreement with one or more investment banks or other purchasers
is entered into, any Securities called for redemption and not surrendered for conversion by the Holders thereof prior to the relevant Redemption Date may, at the option of the Company upon written
notice to the Trustee, be deemed, to the fullest extent permitted by law, acquired by such purchasers from such Holders and (notwithstanding anything to the contrary contained in Article 4)
surrendered by such purchasers for conversion, all as of 11:00 a.m. New York City time on the Redemption Date, subject to payment of the above amount as aforesaid. The Paying Agent shall hold
and pay to the Holders whose Securities are selected for redemption any such amount paid to it for purchase in the same manner as it would money deposited with it by the Company for the redemption of
Securities. Without the Paying Agent's prior written consent, no arrangement between the Company and such purchasers for the purchase and conversion of any Securities shall increase or otherwise
affect any of the powers, duties, responsibilities or obligations of the Paying Agent as set forth in this Indenture, and the Company agrees to indemnify the Paying Agent from, and hold it harmless
against, any loss, liability or expense arising out of or in connection with any such arrangement for the purchase and conversion of any Securities between the Company and such purchasers, including
the costs and expenses incurred by the Paying Agent in the

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defense of any claim or liability arising out of or in connection with the exercise or performance of any of its powers, duties, responsibilities or obligations under this Indenture.



(a)  If
at any time that Securities remain outstanding there shall occur a Change in Control, Securities shall be purchased by the Company at the option of the Holders, as of
the date that is 30 Business Days after the occurrence of the Change in Control (the "Change in Control Purchase Date") at a purchase price equal to 100% of the principal amount of the
Securities, together with accrued and unpaid interest to, but excluding, the Change in Control Purchase Date (the "Change in Control Purchase Price"), subject to satisfaction by or on behalf of any
Holder of the requirements set forth in subsection (c) of this Section 3.9.

A
"Change in Control" shall be deemed to have occurred if any of the following occurs after the date hereof:



For
the purpose of the definition of "Change in Control", (i) "person" and "group" have the meanings given such terms under Section 13(d) and 14(d) of the Exchange Act or
any successor provision to either of the foregoing, and the term "group" includes any group acting for the purpose of acquiring, holding or disposing of securities within the meaning of
Rule 13d-5(b)(1) under the Exchange Act (or any successor provision thereto), (ii) a "beneficial owner" shall be determined in accordance with Rule 13d-3
under the Exchange Act, as in effect on the date of this Indenture, except that the number of shares of Voting Stock of the Company shall be deemed to include, in addition to all outstanding shares of
Voting Stock of the Company and Unissued Shares deemed to be held by the "person" or "group" (as such terms are defined above) or other Person with respect to which the Change in Control determination
is being made, all Unissued Shares deemed to be held by all other Persons, and (iii) the terms "beneficially owned" and "beneficially own" shall have meanings correlative to that of "beneficial
owner". The term "Unissued Shares" means shares of Voting Stock not outstanding that are subject to options, warrants, rights to purchase or conversion privileges exercisable within 60 days of
the date of determination of a Change in Control.

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Notwithstanding
anything to the contrary set forth in this Section 3.9, a Change in Control will not be deemed to have occurred if either:



(b)  Within
10 Business Days after the occurrence of a Change in Control, the Company shall mail a written notice of the Change in Control to the Trustee and to each Holder
(and to beneficial owners as required by applicable law). The notice shall include the form of a Change in Control Purchase Notice to be completed by the Holder and shall state:



If
any of the Securities is in the form of a Global Security, then the Company shall modify such notice to the extent necessary to accord with the procedures of the Depositary applicable
to the repurchase of Global Securities.

(c)  A
Holder may exercise its rights specified in subsection (a) of this Section 3.9 upon delivery of a written notice (which shall be in substantially the
form included inExhibit Ahereto and which may be delivered by letter, overnight courier, hand delivery, facsimile transmission or in any other
written

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form and, in the case of Global Securities, may be delivered electronically or by other means in accordance with the Depositary's customary procedures) of the exercise of such rights (a "Change in
Control Purchase Notice") to any Paying Agent at any time prior to the close of business on the Business Day next preceding the Change in Control Purchase Date.

The
delivery of such Security to any Paying Agent (together with all necessary endorsements) at the office of such Paying Agent shall be a condition to the receipt by the Holder of the
Change in Control Purchase Price therefor.

The
Company shall purchase from the Holder thereof, pursuant to this Section 3.9, a portion of a Security if the principal amount of such portion is $1,000 or an integral multiple
of $1,000. Provisions of the Indenture that apply to the purchase of all of a Security pursuant to Sections 3.9 through 3.14 also apply to the purchase of such portion of such Security.

Notwithstanding
anything herein to the contrary, any Holder delivering to a Paying Agent the Change in Control Purchase Notice contemplated by this subsection (c) shall have the
right to withdraw such Change in Control Purchase Notice in whole or in a portion thereof that is a principal amount of $1,000 or in an integral multiple thereof at any time prior to the close of
business on the Business Day next preceding the Change in Control Purchase Date by delivery of a written notice of withdrawal to the Paying Agent in accordance with Section 3.10.

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

Anything
herein to the contrary notwithstanding, in the case of Global Securities, any Change in Control Purchase Notice may be delivered or withdrawn and such Securities may be
surrendered or delivered for purchase in accordance with the Applicable Procedures as in effect from time to time.



Upon receipt by any Paying Agent of the Change in Control Purchase Notice specified in Section 3.9(c), the Holder of the Security in respect of which such
Change in Control Purchase Notice was given shall (unless such Change in Control Purchase Notice is withdrawn as specified below) thereafter be entitled
to receive the Change in Control Purchase Price with respect to such Security. Such Change in Control Purchase Price shall be paid to such Holder promptly following the later of (a) the Change
in Control Purchase Date with respect to such Security (providedthe conditions in Section 3.9(c) have been satisfied) and (b) the time of
delivery of such Security to a Paying Agent by the Holder thereof in the manner required by Section 3.9(c). Securities in respect of which a Change in Control Purchase Notice has been given by
the Holder thereof may not be converted into shares of Common Stock pursuant to Article 4 on or after the date of the delivery of such Change in Control Purchase Notice unless such Change in
Control Purchase Notice has first been validly withdrawn.

A
Change in Control Purchase Notice may be withdrawn by means of a written notice (which may be delivered by mail, overnight courier, hand delivery, facsimile transmission or in any
other written form and, in the case of Global Securities, may be delivered electronically or by other means in accordance with the Depositary's customary procedures) of withdrawal delivered by the
Holder to a Paying Agent at any time prior to the close of business on the Business Day immediately preceding the Change in Control Purchase Date, specifying the principal amount of the Security or
portion thereof (which must be a principal amount of $1,000 or an integral multiple of $1,000 in excess thereof) with respect to which such notice of withdrawal is being submitted.



On or before 11:00 a.m. New York City time on the Change in Control Purchase Date, the Company shall deposit with the Trustee or with a Paying Agent (other
than the Company or an

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Affiliate of the Company) an amount of money (in immediately available funds if deposited on such Change in Control Purchase Date) sufficient to pay the aggregate Change in Control Purchase Price of
all the Securities or portions thereof that are to be purchased as of such Change in Control Purchase Date. The manner in which the deposit required by this Section 3.11 is made by the Company
shall be at the option of the Company,provided thatsuch deposit shall be made in a manner such that the Trustee or a Paying Agent shall have
immediately available funds on the Change in Control Purchase Date.

If
a Paying Agent holds, in accordance with the terms hereof, money sufficient to pay the Change in Control Purchase Price of any Security for which a Change in Control Purchase Notice
has been tendered and not withdrawn in accordance with this Indenture then, on the Change in Control Purchase Date, such Security will cease to be outstanding and the rights of the Holder in respect
thereof shall terminate (other than the right to receive the Change in Control Purchase Price as aforesaid). The Company shall publicly announce the principal amount of Securities purchased as a
result of such Change in Control on or as soon as practicable after the Change in Control Purchase Date.



Any Security that is to be purchased only in part shall be surrendered at the office of a Paying Agent, and promptly after the Change in Control Purchase Date 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 such authorized denomination or
denominations as may be requested by such Holder, in aggregate principal amount equal to, and in exchange for, the portion of the principal amount of the Security so surrendered that is not purchased.



In connection with any offer to purchase or purchase of Securities under Section 3.9, the Company shall (a) comply with
Rule 13e-4 and Rule 14e-1 (or any successor to either such Rule), if applicable, under the Exchange Act, (b) file the related Schedule TO (or any successor
or similar schedule, form or report) if required under the Exchange Act, and (c) otherwise comply with all federal and state securities laws in connection with such offer to purchase or
purchase of Securities, all so as to permit the rights of the Holders and obligations of the Company under Sections 3.9 through 3.12 to be exercised in the time and in the manner specified therein.



To the extent that the aggregate amount of cash deposited by the Company pursuant to Section 3.11 exceeds the aggregate Change in Control Purchase Price
together with interest, if any, thereon of the Securities or portions thereof that the Company is obligated to purchase, then promptly after the Change in Control Purchase Date the Trustee or a Paying
Agent, as the case may be, shall return any such excess cash to the Company.

ARTICLE 4  CONVERSION



Subject to the further provisions of this Article 4 and paragraph 9 of the Securities, a Holder of a Security may convert the principal amount of
such Security (or any portion thereof equal to $1,000 or any integral multiple of $1,000 in excess thereof) into Common Stock at any time prior to the close of business on the last Business Date prior
to the Final Maturity Date, at the Conversion Price then in

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effect;provided, however, that, if such Security is called for redemption or submitted or presented for purchase pursuant to Article 3, such
conversion right shall terminate at the close of business on the Business Day immediately preceding the Redemption Date or Change in Control Purchase Date, as the case may be, for such Security or
such earlier date as the Holder presents such Security for redemption or for purchase (unless the Company shall default in making the redemption payment or Change in Control Purchase Price payment
when due, in which case the conversion right shall terminate at the close of business on the date such default is cured and such Security is redeemed or purchased, as the case may be). The number of
shares of Common Stock issuable upon conversion of a Security shall be determined by dividing the principal amount of the Security or portion thereof surrendered for conversion by the Conversion Price
in effect on the Conversion Date. The initial Conversion Price is set forth in paragraph 9 of the Securities and is subject to adjustment as provided in this Article 4.

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

A
Security in respect of which a Holder has delivered a Change in Control Purchase Notice pursuant to Section 3.9 exercising the option of such Holder to require the Company to
purchase such Security may be converted only if such Change in Control Purchase Notice is withdrawn by a written notice of withdrawal delivered to a Paying Agent prior to the close of business on the
Business Day immediately preceding the Change in Control Purchase Date in accordance with Section 3.9.

A
Holder of Securities is not entitled to any rights of a holder of Common Stock until such Holder has converted its Securities to Common Stock, and only to the extent such Securities
are deemed to have been converted into Common Stock pursuant to this Article 4.



To convert a Security, a Holder must (a) complete and manually sign the conversion notice on the back of the Security and deliver such notice to a
Conversion Agent, (b) surrender the Security to a Conversion Agent, (c) furnish appropriate endorsements and transfer documents if required by a Registrar or a Conversion Agent, and
(d) pay any transfer or similar tax, if required. The date on which
the Holder satisfies all of those requirements is the "Conversion Date." As soon as practicable after the Conversion Date, the Company shall deliver to the Holder through a Conversion Agent a
certificate for the number of whole shares of Common Stock issuable upon the conversion and cash in lieu of any fractional shares pursuant to Section 4.3. Anything herein to the contrary
notwithstanding, in the case of Global Securities, conversion notices may be delivered and such Securities may be surrendered for conversion in accordance with the Applicable Procedures as in effect
from time to time.

The
person in whose name the Common Stock certificate is registered shall be deemed to be a stockholder of record on the Conversion Date;provided, however,that no surrender of a Security on any date when
the stock transfer books of the Company shall be closed shall be effective to constitute the person or persons entitled to
receive the shares of Common Stock upon such conversion as the record holder or holders of such shares of Common Stock on such date, but such surrender shall be effective to constitute the person or
persons entitled to receive such shares of Common Stock as the record holder or holders thereof for all purposes at the close of business on the next succeeding day on which such stock transfer books
are open;provided, further,that such conversion shall be at the Conversion Price in effect on the Conversion Date as if the stock transfer books of
the Company had not been closed. Upon conversion of a Security, such person shall no longer be a Holder of such Security. No payment or adjustment will be made for dividends or distributions on shares
of Common Stock issued upon conversion of a Security.

Securities
so surrendered for conversion (in whole or in part) during the period from the close of business on any regular record date to the opening of business on the next succeeding
interest payment

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date (excluding Securities or portions thereof called for redemption or presented for purchase upon a Change in Control on a Redemption Date or Change in Control Purchase Date, as the case may be,
during the period beginning at the close of business on a regular record date and ending at the opening of business on the first Business Day after the next succeeding interest payment date, or if
such interest payment date is not a Business Day, the second such Business Day) shall also be accompanied by payment in funds acceptable to the Company of an amount equal to the interest payable on
such interest payment date on the principal amount of such Security then being converted, and such interest shall be payable to such registered Holder notwithstanding the conversion of such Security,
subject to the provisions of this Indenture relating to the payment of defaulted interest by the Company. Except as otherwise provided in this Section 4.2, no payment or adjustment will be made
for accrued interest on a converted Security. If the Company defaults in the payment of interest payable on such interest payment date, the Company shall promptly repay such funds to such Holder.

Nothing
in this Section shall affect the right of a Holder in whose name any Security is registered at the close of business on a record date to receive the interest payable on such
Security on the related interest payment date in accordance with the terms of this Indenture and the Securities. If a 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 aggregate principal amount of Securities converted.

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



The Company will not issue fractional shares of Common Stock upon conversion of Securities. In lieu thereof, the Company will pay an amount in cash for the
current market value of the fractional shares. The current market value of a fractional share shall be determined, (calculated to the nearest 1/1000th of a share) by multiplying the
Closing Price (determined as set forth in Section 4.6(d)) of the Common Stock on the Trading Day immediately prior to the Conversion Date by such fractional share and rounding the product to
the nearest whole cent.



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
such 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 certificate 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 regulation.



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

All
shares of Common Stock delivered upon conversion of the Securities shall be newly issued 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.

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The
Company will endeavor promptly to comply with all federal and state securities laws regulating the offer and delivery of shares of Common Stock upon conversion of Securities, if any,
and will list or cause to have quoted such shares of Common Stock on each national securities exchange or on the Nasdaq National Market or other over-the-counter market or such
other market on which the Common Stock is then listed or quoted;provided, however,that if rules of such automated quotation system or exchange permit
the Company to defer the listing of such Common Stock until the first conversion of the Notes into Common Stock in accordance with the provisions of this Indenture, the Company covenants to list such
Common Stock issuable upon conversion of the Notes in accordance with the requirements of such automated quotation system or exchange at such time. Any Common Stock issued upon conversion of a
Security hereunder which at the time of conversion was a Transfer Restricted Security will also be a Transfer Restricted Security.



The conversion price as stated in paragraph 9 of the Securities (the "Conversion Price") shall be adjusted from time to time by the Company as follows:

(a)  In
case the Company shall (i) pay a dividend on its Common Stock in shares of Common Stock, (ii) make a distribution on its Common Stock in shares of
Common Stock, (iii) subdivide its outstanding Common Stock into a greater number of shares, or (iv) combine its outstanding Common Stock into a smaller number of shares, the Conversion
Price in effect immediately prior thereto shall be adjusted so that the Holder of any Security thereafter surrendered for conversion shall be entitled to receive that number of shares of Common Stock
which it would have owned had such Security been converted immediately prior to the happening of such event. An adjustment made pursuant to this subsection (a) shall become effective
immediately after the record date in the case of a dividend or distribution and shall become effective immediately after the effective date in the case of subdivision or combination.

(b)  In
case the Company shall issue rights or warrants to all or substantially all holders of its Common Stock entitling them (for a period commencing no earlier than the
record date described below and expiring not more than 60 days after such record date) to subscribe for or purchase shares of Common Stock (or securities convertible into Common Stock) at a
price per share (or having a conversion price per share) less than the Current Market Price per share of Common Stock (as determined in accordance with subsection (d) of this
Section 4.6) on the record date for the determination of stockholders entitled to receive such rights or warrants, the Conversion Price in effect immediately prior thereto shall be adjusted so
that the same shall equal the price determined by multiplying the Conversion Price in effect immediately prior to such record date by a fraction of which the numerator shall be the number of shares of
Common Stock outstanding on such record date plus the number of shares which the aggregate offering price of the total number of shares of Common Stock so offered (or the aggregate conversion price of
the convertible securities so offered, which shall be determined by multiplying the number of shares of Common Stock issuable upon conversion of such convertible securities by the conversion price per
share of Common Stock pursuant to the terms of such convertible securities) would purchase at the Current Market Price per share (as defined in subsection
(d) of this Section 4.6) of Common Stock on such record date, and of which the denominator shall be the number of shares of Common Stock outstanding on such record date plus the number
of additional shares of Common Stock offered (or into which the convertible securities so offered are convertible). Such adjustment shall be made successively whenever any such rights or warrants are
issued, and shall become effective immediately after such record date. If at the end of the period during which such rights or warrants are exercisable not all rights or warrants shall have been
exercised, the adjusted Conversion Price shall be immediately readjusted to what it would have been based upon the number of additional shares of Common Stock actually issued (or the number of shares
of Common Stock issuable upon conversion of convertible securities actually issued).

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(c)  In
case the Company shall distribute to all or substantially all holders of its Common Stock any shares of capital stock of the Company (other than Common Stock),
evidences of indebtedness or other non-cash assets (including securities of any person other than the Company but excluding (1) dividends or distributions paid exclusively in cash
or (2) dividends or distributions referred to in subsection (a) of this Section 4.6), or shall distribute to all or substantially all holders of its Common Stock rights or
warrants to subscribe for or purchase any of its securities (excluding those rights and warrants referred to in subsection (b) of this Section 4.6 and also excluding the distribution of
rights to all holders of Common Stock pursuant to the adoption of a stockholders rights plan or the detachment of such rights under the terms of such stockholder rights plan), then in each such case
the Conversion Price shall be adjusted so that the same shall equal the price determined by multiplying the current Conversion Price by a fraction of which the numerator shall be the Current Market
Price per share (as defined in subsection (d) of this Section 4.6) of the Common Stock on the record date mentioned below less the fair market value on such record date (as determined by
the Board of Directors, whose determination shall be conclusive evidence of such fair market value and which shall be evidenced by an Officers' Certificate delivered to the Trustee) of the portion of
the capital stock, evidences of indebtedness or other non-cash assets so distributed or of such rights or warrants applicable to one share of Common Stock (determined on the basis of the
number of shares of Common Stock outstanding on the record date), and of which the denominator shall be the Current Market Price per share (as defined in subsection (d) of this
Section 4.6) of the Common Stock on such record date. Such adjustment shall be made successively whenever any such distribution is made and shall become effective immediately after the record
date for the determination of shareholders entitled to receive such distribution.

In
the event the then fair market value (as so determined) of the portion of the capital stock, evidences of indebtedness or other non-cash assets so distributed or of such
rights or warrants applicable to one share of Common Stock is equal to or greater than the Current Market Price per share of the Common Stock on such record date, in lieu of the foregoing adjustment,
adequate provision shall be made so that each holder of a Security shall have the right to receive upon conversion the amount of capital stock, evidences of indebtedness or other non-cash
assets so distributed or of such rights or warrants such holder would have received had such holder converted each Security on such record date. In the event that such dividend or distribution is not
so paid or made, the Conversion Price shall again be adjusted to be the Conversion Price which would then be in effect if such dividend or distribution had not been declared. If the Board of Directors
determines the fair market value of any distribution for purposes of this Section 4.6(c) by reference to the actual or when issued trading market for any securities, it must in doing so
consider the prices in such market over the same period used in computing the Current Market Price of the Common Stock.

In
the event that the Company implements a preferred shares rights plan ("Rights Plan"), upon conversion of the Securities into Common Stock, to the extent that the Rights Plan has been
implemented and is still in effect upon such conversion, the holders of Securities will receive, in addition to the Common Stock, the rights described therein (whether or not the rights have separated
from the Common Stock at the time of conversion), subject to the limitations set forth in the Rights Plan. Any distribution of rights or warrants pursuant to a Rights Plan complying with the
requirements set forth in the immediately preceding sentence of this paragraph shall not constitute a distribution of rights or warrants pursuant to this Section 4.6(c).

Rights
or warrants distributed by the Company to all holders of Common Stock entitling the holders thereof to subscribe for or purchase shares of the Company's Capital Stock (either
initially or under certain circumstances), which rights or warrants, until the occurrence of a specified event or events ("Trigger Event"): (i) are deemed to be transferred with such shares of
Common Stock; (ii) are not exercisable; and (iii) are also issued in respect of future issuances of Common Stock, shall be deemed not to have been distributed for purposes of this
Section 4.6 (and no adjustment to the

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Conversion Price under this Section 4.6 will be required) until the occurrence of the earliest Trigger Event, whereupon such rights and warrants shall be deemed to have been distributed and an
appropriate adjustment (if any is required) to the Conversion Price shall be made under this Section 4.6(c). If any such right or warrant, including any such existing rights or warrants
distributed prior to the date of this Indenture, are subject to events, upon the occurrence of which such rights or warrants become exercisable to purchase different securities, evidences of
indebtedness or other assets, then the date of the occurrence of any and each such event shall be deemed to be the date of distribution and record date with respect to new rights or warrants with such
rights (and a termination or expiration of the existing rights or warrants without exercise by any of the holders thereof). In addition, in the event of any distribution (or deemed distribution) of
rights or warrants, or any Trigger Event or other event (of the type described in the preceding sentence) with respect thereto that was counted for purposes of calculating a distribution amount for
which an adjustment to the Conversion Price under this Section 4.6 was made, (1) in the case of any such rights or warrants which shall all have been redeemed or repurchased without
exercise by any holders thereof, the Conversion Price shall be readjusted upon such final redemption or repurchase to give effect to such distribution or Trigger Event, as the case may be, as though
it were a cash distribution, equal to the per share redemption or repurchase price received by a holder or holders of Common Stock with respect to such rights or warrants (assuming such holder had
retained such rights or warrants), made to all holders of Common Stock as of the date of such redemption or repurchase, and (2) in the case of such rights or warrants which shall have expired
or been terminated without exercise by any holders thereof, the Conversion Price shall be readjusted as if such rights and warrants had not been issued.



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(d)  For
the purpose of any computation under subsections (b) and (c) of this Section 4.6, the current market price (the "Current Market Price") per
share of Common Stock on any date shall be deemed to be the average of the daily closing prices for the 30 consecutive Trading Days commencing 45 Trading Days before (i) the Determination Date
or the Expiration Date, as the case may be, with respect to distributions or tender offers under subsection (c) of this Section 4.6 or (ii) the record date with respect to
distributions, issuances or other events requiring such computation under subsection (b) or (c) of this Section 4.6. The closing price (the "Closing Price") for each day shall be
the last reported sales price or, in case no such reported sale takes place on such date, the average of the reported closing bid and asked prices in either case on the Nasdaq National Market (the
"NNM") or, if the Common Stock is not listed or admitted to trading on the NNM, on the principal national securities exchange on which the Common Stock is listed or admitted to trading or, if not
listed or admitted to trading on the NNM or any national securities exchange, the last reported sales price of the Common Stock as quoted on NASDAQ or, in case no reported sales takes place, the
average of the closing bid and asked prices as quoted on NASDAQ or any comparable system or, if the Common Stock is not quoted on NASDAQ or any comparable system, the closing sales price or, in case
no reported sale takes place, the average of the closing bid and asked prices, as furnished by any two members of the National Association of Securities Dealers, Inc. selected from time to time
by the Company for that purpose. If no such prices are available, the Current Market Price per share shall be the fair value of a share of Common Stock as determined by the Board of Directors (which
shall be evidenced by an Officers' Certificate delivered to the Trustee).

(e)  In
any case in which this Section 4.6 shall require that an adjustment be made following a record date or a Determination Date or Expiration Date, as the case may
be, established for purposes of this
Section 4.6, the Company may elect to defer (but only until five Business Days following the filing by the Company with the Trustee of the certificate described in Section 4.9) issuing
to the Holder of any Security converted after such record date or Determination Date or Expiration Date the shares of Common Stock and other capital stock of the Company issuable upon such conversion
over and above the shares of Common Stock and other capital stock of the Company issuable upon such conversion only on the basis of the Conversion Price prior to adjustment; and, in lieu of the shares
the issuance of which is so deferred, the Company shall issue or cause its transfer agents to issue due bills or other appropriate evidence prepared by the Company of the right to receive such shares.
If any distribution in respect of which an adjustment to the Conversion Price is required to be made as of the record date or Determination Date or Expiration Date therefor is not thereafter made or
paid by the Company for any reason, the Conversion Price shall be readjusted to the Conversion Price which would then be in effect if such record date had not been fixed or such effective date or
Determination Date or Expiration Date had not occurred.



No adjustment in the Conversion Price shall be required unless the adjustment would require an increase or decrease of at least 1% in the Conversion Price as last
adjusted; provided, however, that any adjustments which by reason of this Section 4.7 are not required to be made shall be carried forward and taken into account in any subsequent adjustment.
All calculations under this Article 4 shall be made to the nearest cent or to the nearest one-hundredth of a share, as the case may be.

No
adjustment need be made for issuances of Common Stock pursuant to a Company plan for reinvestment of dividends or interest or for a change in the par value or a change to no par value
of the Common Stock.

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To
the extent that the Securities become convertible into the right to receive cash, no adjustment need be made thereafter as to the cash. Interest will not accrue on the cash.



The Company shall be entitled to make such reductions in the Conversion Price, in addition to those required by Section 4.6, as it in its discretion shall
determine to be advisable in order that any stock dividends, subdivisions of shares, distributions of rights to purchase stock or securities or distributions of securities convertible into or
exchangeable for stock hereafter made by the Company to its stockholders shall not be taxable.

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Whenever the Conversion Price or conversion privilege is adjusted, the Company shall promptly mail to Securityholders a notice of the adjustment and file with the
Trustee an Officers' Certificate briefly stating the facts requiring the adjustment and the manner of computing it. Unless and until the Trustee shall receive an Officers' Certificate setting forth an
adjustment of the Conversion Price, the Trustee may assume without inquiry that the Conversion Price has not been adjusted and that the last Conversion Price of which it has knowledge remains in
effect.



In the event that:



If any of the following shall occur, namely: (a) any reclassification or change of shares of Common Stock issuable upon conversion of the Securities (other
than a change in par value, or from par value to no par value, or from no par value to par value, or as a result of a subdivision or combination, or any other change for which an adjustment is
provided in Section 4.6); (b) any consolidation or merger or combination to which the Company is a party other than a merger in which the Company is the continuing corporation and which
does not result in any reclassification of, or change (other than in par value, or from par value to no par value, or from no par value to par value, or as a result of a subdivision or combination)
in, outstanding shares of Common Stock; or (c) any sale or conveyance as an entirety or substantially as an entirety of the property and assets of the Company, directly or indirectly, to any
person, then the Company, or such successor, purchasing or transferee corporation, as the case may be, shall, as a condition precedent to such reclassification, change, combination, consolidation,
merger, sale or conveyance, execute and deliver to the Trustee a supplemental indenture providing that the Holder of each Security then outstanding shall have the right to convert such Security into
the kind and amount of shares of stock and other securities and property (including cash) receivable upon such reclassification, change, combination, consolidation, merger, sale or conveyance by a
holder of the number of shares of Common Stock deliverable upon conversion of such Security immediately prior to such reclassification, change, combination, consolidation, merger, sale or conveyance.
Such supplemental indenture shall provide for adjustments of the Conversion Price which shall be as nearly equivalent as may be practicable to the adjustments of the Conversion Price provided for in
this Article 4. If, in the case of any such consolidation, merger, combination, sale or conveyance, the stock or other securities and property (including cash) receivable thereupon by a holder
of Common Stock include shares of stock or other securities and property of a person other than the successor, purchasing or transferee corporation, as the case may be, in such consolidation, merger,
combination, sale or conveyance, then such supplemental indenture shall also be executed by such

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other person and shall contain such additional provisions to protect the interests of the Holders of the Securities as the Board of Directors shall reasonably consider necessary by reason of the
foregoing. The provisions of this Section 4.11 shall similarly apply to successive reclassifications, changes, combinations, consolidations, mergers, sales or conveyances.

In
the event the Company shall execute a supplemental indenture pursuant to this Section 4.11, the Company shall promptly file with the Trustee (x) an Officers' Certificate
briefly stating the reasons therefor, the kind or amount of shares of stock or other securities or property (including cash) receivable by Holders of the Securities upon the conversion of their
Securities after any such reclassification, change, combination, consolidation, merger, sale or conveyance, any adjustment to be made with respect thereto and that all conditions precedent have been
complied with and (y) an Opinion of Counsel that all conditions precedent have been complied with, and shall promptly mail notice thereof to all Holders.



The Trustee shall have no duty to determine when an adjustment under this Article 4 should be made, how it should be made or what such adjustment should
be, but may accept as conclusive evidence of that fact or the correctness of any such adjustment, and shall be protected in relying upon, an Officers' Certificate including the Officers' Certificate
with respect thereto which the Company is obligated to file with the Trustee pursuant to Section 4.9. The Trustee makes no representation as to the validity or value of any securities or assets
issued upon conversion of Securities, and the Trustee shall not be responsible for the Company's failure to comply with any provisions of this Article 4.

The
Trustee shall not be under any responsibility to determine the correctness of any provisions contained in any supplemental indenture executed pursuant to Section 4.11, but may
accept as conclusive evidence of the correctness thereof, and shall be fully protected in relying upon, the Officers' Certificate with respect thereto which the Company is obligated to file with the
Trustee pursuant to Section 4.11.



The Company from time to time may reduce the Conversion Price by any amount for any period of time if the period is at least 20 days and if the reduction
is irrevocable during the period if our Board of Directors determines that such reduction would be in the best interest of the Company or to avoid or diminish income tax to holders of shares of our
Common Stock in connection with a dividend or distribution of stock or similar event, and the Company provides 15 days prior notice of any reduction in the Conversion Price; provided, however,that
in no event may the Company reduce the Conversion Price to be less than the par value of a share of Common Stock.

ARTICLE 5  SUBORDINATION



The Company covenants and agrees, and each Holder of Securities issued hereunder by its acceptance thereof likewise covenants and agrees, that all Securities
shall be issued subject to the provisions of this
Article 5; and each Person holding any Security, whether upon original issue or upon transfer, assignment or exchange thereof, accepts and agrees to be bound by such provisions.

The
payment of the principal of, premium, if any, and interest (including Additional Interest, if any) on all Securities (including, but not limited to, the Redemption Price with respect
to the Securities called for redemption or the Change in Control Purchase Price with respect to the Securities subject to purchase in accordance with Article 3 as provided in this Indenture)
issued hereunder shall, to the

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extent and in the manner hereinafter set forth, be subordinated and subject in right of payment to the prior payment in full in cash or payment satisfactory to the holders of Senior Indebtedness of
all Senior Indebtedness, whether outstanding at the date of this Indenture or thereafter incurred.

No
provision of this Article 5 shall prevent the occurrence of any default or Event of Default hereunder.



No payment shall be made with respect to the principal of, or premium, if any, or interest (including Additional Interest, if any) on the Securities (including,
but not limited to, the Redemption Price with respect to the Securities to be called for redemption or the Change in Control Purchase Price with respect to the Securities subject to purchase in
accordance with Article 3 as provided in this Indenture), except payments and distributions made by the Trustee as permitted by the first or second paragraph of Section 5.5, if:

(i)    a
default in the payment of principal, premium, interest, rent or other obligations due on any Designated Senior Indebtedness occurs and is continuing (or, in the case
of Designated Senior Indebtedness for which there is a period of grace, in the event of such a default that continues beyond the period of grace, if any, specified in the instrument or lease
evidencing such Designated Senior Indebtedness), unless and until such default shall have been cured or waived or shall have ceased to exist; or

(ii)  a
default, other than a payment default, on a Designated Senior Indebtedness occurs and is continuing that then permits holders of such Designated Senior Indebtedness
to accelerate its maturity and the Trustee receives a notice of the default (a "Payment Blockage Notice") from a Representative or holder of Designated Senior Indebtedness or the Company.

Subject
to the provisions of Section 5.5, if the Trustee receives any Payment Blockage Notice pursuant to clause (ii) above, no subsequent Payment Blockage Notice shall be
effective for purposes of this Section unless and until (a) at least 365 days shall have elapsed since the initial effectiveness of the immediately prior Payment Blockage Notice; and
(b) all scheduled payments on the Securities that have come due have been paid in full in cash. No nonpayment default that existed or was continuing on the date of delivery of any Payment
Blockage Notice to the Trustee (unless such default was waived, cured or otherwise ceased to exist and thereafter subsequently reoccurred) shall be, or be made, the basis for a subsequent Payment
Blockage Notice.

The
Company may and shall resume payments on and distributions in respect of the Securities upon the earlier of:

(a)  in
the case of a default referred to in clause (i) above, the date upon which the default is cured or waived or ceases to exist, or

(b)  in
the case of a default referred to in clause (ii) above, the earlier of the date on which such default is cured or waived or ceases to exist or 179 days
pass after the date on which the applicable Payment Blockage Notice is received, if the maturity of such Designated Senior Indebtedness has not been accelerated, unless this Article 5 otherwise
prohibits the payment or distribution at the time of such payment or distribution.

Upon
any payment by the Company, or distribution of assets of the Company of any kind or character, whether in cash, property or securities, to creditors upon any dissolution or
winding-up or liquidation or reorganization of the Company (whether voluntary or involuntary) or in bankruptcy, insolvency, receivership or similar proceedings, all amounts due or to
become due upon all Senior Indebtedness shall first be paid in full in cash, or other payments satisfactory to the holders of Senior Indebtedness before any payment is made on account of the principal
of, premium, if any, or interest

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(including Additional Interest, if any) on the Securities (except payments made pursuant to Article 10 from monies deposited with the Trustee pursuant thereto prior to commencement of
proceedings for such dissolution, winding-up, liquidation or reorganization); and upon any such dissolution or winding-up or liquidation or reorganization of the Company or
bankruptcy, insolvency, receivership or other proceeding, any payment by the Company, or distribution of assets of the Company of any kind or character, whether in cash, property or securities, to
which the Holders of the Securities or the Trustee would be entitled, except for the provision of this Article 5, shall (except as aforesaid) be paid by the Company or by any receiver, trustee
in bankruptcy, liquidating trustee, agent or other Person making such payment or distribution, or by the Holders of the Securities or by the Trustee under this Indenture if received by them or it,
directly to the holders of Senior Indebtedness (pro rata to such holders on the basis of the respective amounts of Senior Indebtedness held by such holders, or as otherwise required by law or a court
order) or their representative or representatives, or to the trustee or trustees under any indenture pursuant to which any instruments evidencing any Senior Indebtedness may have been issued, as their
respective interests may appear, to the extent necessary to pay all Senior Indebtedness in full in cash, or other payment satisfactory to the holders of Senior Indebtedness, after
giving effect to any concurrent payment or distribution to or for the holders of Senior Indebtedness, before any payment or distribution is made to the Holders of the Securities or to the Trustee.

For
purposes of this Article 5, the words, "cash, property or securities" shall not be deemed to include shares of stock of the Company as reorganized or readjusted, or securities
of the Company or any other corporation provided for by a plan of reorganization or readjustment, the payment of which is subordinated at least to the extent provided in this Article 5 with
respect to the Securities to the payment of all Senior Indebtedness which may at the time be outstanding;provided that(i) the Senior
Indebtedness is assumed by the new corporation, if any, resulting from any reorganization or readjustment, and (ii) the rights of the holders of Senior Indebtedness (other than leases which are
not assumed by the Company or the new corporation, as the case may be) are not, without the consent of such holders, altered by such reorganization or readjustment. The consolidation of the Company
with, or the merger of the Company into, another corporation or the liquidation or dissolution of the Company following the conveyance, transfer or lease of its property as an entirety, or
substantially as an entirety, to another corporation upon the terms and conditions provided for in Article 7 shall not be deemed a dissolution, winding-up, liquidation or
reorganization for the purposes of this Section 5.2 if such other corporation shall, as a part of such consolidation, merger, conveyance, transfer or lease, comply with the conditions stated in
Article 7.

In
the event of the acceleration of the Securities because of an Event of Default, no payment or distribution shall be made to the Trustee or any Holder of Securities in respect of the
principal of, premium, if any, or interest (including Additional Interest, if any) on the Securities by the Company (including, but not limited to, the Redemption Price with respect to the Securities
called for redemption or the Change in Control Purchase Price with respect to the Securities subject to purchase in accordance with Article 3 as provided in this Indenture), except payments and
distributions made by the Trustee as permitted by Section 5.5, until all Senior Indebtedness has been paid in full in cash or other payment satisfactory to the holders of Senior Indebtedness or
such acceleration is rescinded in accordance with the terms of this Indenture. If payment of the Securities is accelerated because of an Event of Default, the Company shall promptly notify holders of
Senior Indebtedness of such acceleration.

In
the event that, notwithstanding the foregoing provisions, any payment or distribution of assets of the Company of any kind or character, whether in cash, property or securities
(including, without limitation, by way of setoff or otherwise), prohibited by the foregoing, shall be received by the Trustee or the Holders of the Securities before all Senior Indebtedness is paid in
full, in cash or other payment satisfactory to the holders of Senior Indebtedness, or provision is made for such payment thereof in accordance with its terms in cash or other payment satisfactory to
the holders of Senior Indebtedness,

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such payment or distribution shall be held in trust for the benefit of and shall be paid over or delivered to the holders of Senior Indebtedness or their representative or representatives, or to the
trustee or trustees under any indenture pursuant to which any instruments evidencing any Senior Indebtedness may have been issued, as their respective interests may appear, as calculated by the
Company, for application to the payment of all Senior Indebtedness remaining unpaid to the extent necessary to pay all Senior Indebtedness in full, in cash or other payment satisfactory to the holders
of Senior Indebtedness, after giving effect to any concurrent payment or distribution to or for the holders of such Senior Indebtedness.

Nothing
in this Section 5.2 shall apply to claims of, or payments to, the Trustee under or pursuant to Section 9.7. This Section 5.2 shall be subject to the further
provisions of Section 5.5.



Subject to the payment in full, in cash or other payment satisfactory to the holders of Senior Indebtedness, of all Senior Indebtedness, the rights of the Holders
of the Securities shall be subrogated to the extent of the payments or distributions made to the holders of such Senior Indebtedness pursuant to the provisions of this Article 5 (equally and
ratably with the holders of all indebtedness of the Company which by its express terms is subordinated to other indebtedness of the Company to substantially the same extent as the Securities are
subordinated and is entitled to like rights of subrogation) to the rights of the holders of Senior Indebtedness to receive payments or distributions of cash, property or securities of the Company
applicable to the Senior Indebtedness until the principal, premium, if any, and interest (including Additional Interest, if any) on the Securities shall be paid in full in cash or other payment
satisfactory to the holders of Senior Indebtedness; and, for the purposes of such subrogation, no payments or distributions to the holders of the Senior Indebtedness of any cash, property or
securities to which the Holders of the Securities or the Trustee would be entitled except for the provisions of this Article 5, and no payment over pursuant to the provisions of this
Article 5, to or for the benefit of the holders of Senior Indebtedness by Holders of the Securities or the Trustee, shall, as between the Company, its creditors other than holders of Senior
Indebtedness, and the Holders of the Securities, be deemed to be a payment by the Company to or on account of the Senior Indebtedness; and no payments or distributions of cash, property or securities
to or for the benefit of the Holders of the Securities pursuant to the subrogation provisions of this Article 5, which would otherwise have been paid to the holders of Senior Indebtedness shall
be deemed to be a payment by the Company to or for the account of the Securities. It is understood that the provisions of this Article 5 are and are intended solely for the purposes of defining
the relative rights of the Holders of the Securities, on the one hand, and the holders of the Senior Indebtedness, on the other hand.

Nothing
contained in this Article 5 or elsewhere in this Indenture or in the Securities is intended to or shall impair, as among the Company, its creditors other than the holders
of Senior Indebtedness, and the Holders of the Securities, the obligation of the Company, which is absolute and unconditional, to pay to the Holders of the Securities the principal of (and premium, if
any) and interest on the Securities as and when the same shall become due and payable in accordance with their terms, or is intended to or shall affect the relative rights of the Holders of the
Securities and creditors of the Company other than the holders of the Senior Indebtedness, nor shall anything herein or therein prevent the Trustee or the Holder of any Security from exercising all
remedies otherwise permitted by applicable law upon default under this Indenture, subject to the rights, if any, under this Article 5 of the holders of Senior Indebtedness in respect of cash,
property or securities of the Company received upon the exercise of any such remedy.

Upon
any payment or distribution of assets of the Company referred to in this Article 5, the Trustee, subject to the provisions of Section 9.1, and the Holders of the
Securities shall be entitled to rely upon
any order or decree made by any court of competent jurisdiction in which such bankruptcy, dissolution, winding-up, liquidation or reorganization proceedings are pending, or a certificate
of the

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receiver, trustee in bankruptcy, liquidating trustee, agent or other person making such payment or distribution, delivered to the Trustee or to the Holders of the Securities, for the purpose of
ascertaining the persons entitled to participate in such distribution, the holders of the Senior Indebtedness and other indebtedness of the Company, the amount thereof or payable thereon and all other
facts pertinent thereto or to this Article 5.



Each Holder of a Security by the Holder's acceptance thereof authorizes and directs the Trustee on the Holder's behalf to take such action as may be necessary or
appropriate to effectuate the subordination as provided in this Article 5 and appoints the Trustee to act as the Holder's attorney-in-fact for any and all such purposes.
If the Trustee does not file a proper proof of claim or proof of debt in the form required in any proceeding referred to in Section 5.3 hereof at least 30 days before the
expiration of the time to file such claim, the holders of any Senior Indebtedness or their representatives are hereby authorized to file an appropriate claim for and on behalf of the Holders of the
Securities.



The Company shall give prompt written notice in the form of an Officers' Certificate to a Trust Officer of the Trustee and to any Paying Agent of any fact known
to the Company which would prohibit the making of any payment of monies to or by the Trustee or any Paying Agent in respect of the Securities pursuant to the provisions of this Article 5.
Notwithstanding the provisions of this Article 5 or any other provision of this Indenture, the Trustee shall not be charged with knowledge of the existence of any facts which would prohibit the
making of any payment of monies to or by the Trustee in respect of the Securities pursuant to the provisions of this Article 5, unless and until a Trust Officer of the Trustee shall have
received written notice thereof at the Corporate Trust Office from the Company (in the form of an Officers' Certificate) or a Representative or a Holder or Holders of Senior Indebtedness or from any
trustee thereof; and before the receipt of any such written notice, the Trustee, subject to the provisions of Section 9.1, shall be entitled in all respects to assume that no such facts exist; provided thatif on a date not less than one Business Day prior to the date upon which by the terms hereof any such monies may become payable for any
purpose (including, without limitation, the payment of the principal of, or premium, if any, or interest on any Security) the Trustee shall not have received, with respect to such monies, the notice
provided for in this Section 5.5, then, anything herein contained to the contrary notwithstanding, the Trustee shall have full power and authority to receive such monies and to apply the same
to the purpose for which they were received, and shall not be affected by any notice to the contrary which may be received by it on or after such prior date. Notwithstanding anything in this
Article 5 to the contrary, nothing shall prevent any payment by the Trustee to the Holders of monies deposited with it pursuant to Article 10, and any such payment shall not be subject
to the provisions of Article 5.

The
Trustee, subject to the provisions of Section 9.1, shall be entitled to rely on the delivery to it of a written notice by a Representative or a person representing himself to
be a holder of Senior Indebtedness (or a trustee on behalf of such holder) to establish that such notice has been given by a Representative or a holder of Senior Indebtedness or a trustee on behalf of
any such holder or holders. In the event that the Trustee determines in good faith that further evidence is required with respect to the right of any person as a holder of Senior Indebtedness to
participate in any payment or distribution pursuant to this Article 5, the Trustee may request such Person to furnish evidence to the reasonable satisfaction of the Trustee as to the amount of
Senior Indebtedness held by such Person, the extent to which such Person is entitled to participate in such payment or distribution and any other facts pertinent to the rights of such Person under
this Article 5, and if such evidence is not furnished the

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Trustee may defer any payment to such Person pending judicial determination as to the right of such Person to receive such payment.



The Trustee in its individual capacity shall be entitled to all the rights set forth in this Article 5 in respect of any Senior Indebtedness at any time
held by it, to the same extent as any other holder of Senior Indebtedness, and nothing in Section 9.11 or elsewhere in this Indenture shall deprive the Trustee of any of its rights as such
holder.

With
respect to the holders of Senior Indebtedness, the Trustee undertakes to perform or to observe only such of its covenants and obligations as are specifically set forth in this
Article 5, and no implied covenants or obligations with respect to the holders of Senior Indebtedness shall be read into this Indenture against the Trustee. The Trustee shall not be deemed to
owe any fiduciary duty to the holders of Senior Indebtedness and, subject to the provisions of Section 9.1, the Trustee shall not be liable to any holder of Senior Indebtedness if it shall pay
over or deliver to Holders of Securities, the Company or any other person money or assets to which any holder of Senior Indebtedness shall be entitled by virtue of this Article 5 or otherwise.



No right of any present or future holder of any Senior Indebtedness to enforce subordination as herein provided shall at any time in any way be prejudiced or
impaired by any act or failure to act on the part of the Company or by any act or failure to act, in good faith, by any such holder, or by any noncompliance by the Company with the terms, provisions
and covenants of this Indenture, regardless of any knowledge thereof which any such holder may have or otherwise be charged with.



For the purposes of this Article 5 only, (1) the issuance and delivery of junior securities upon conversion of Securities in accordance with
Article 4 shall not be deemed to constitute a payment or distribution on account of the principal of (or premium, if any) or interest on Securities or on account of the purchase or other
acquisition of Securities, and (2) the payment, issuance or delivery of cash (except in satisfaction of fractional shares pursuant to Section 4.3), property or securities (other than
junior securities) upon conversion of a Security shall be deemed to constitute payment on account of the principal of such Security. For the purposes of this Section 5.8, the term "junior
securities" means (a) shares of any stock of any class of the Company, or (b) securities of the Company which are subordinated in right of payment to all Senior Indebtedness which may be
outstanding at the time of issuance or delivery of such securities to substantially the same extent as, or to a greater extent than, the Securities are so subordinated as provided in this Article.
Nothing contained in this Article 5 or elsewhere in this Indenture or in the Securities is intended to or shall impair, as among the Company, its creditors other than holders of Senior
Indebtedness and the Holders, the right, which is absolute and unconditional, of the Holder of any Security to convert such Security in accordance with Article 4.



If at any time any Paying Agent other than the Trustee shall have been appointed by the Company and be then acting hereunder, the term "Trustee" as used in this
Article shall (unless the context otherwise requires) be construed as extending to and including such Paying Agent within its meaning as fully for all intents and purposes as if such Paying Agent were
named in this Article in addition to or in place of the Trustee;provided, however,that the first paragraph of Section 5.5 shall not apply to
the Company or any Affiliate of the Company if it or such Affiliate acts as Paying Agent.

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The holders of Senior Indebtedness (including, without limitation, Designated Senior Indebtedness) shall have the right to rely upon this Article 5, and no
amendment or modification of the provisions contained herein shall diminish the rights of such holders unless such holders shall have agreed in writing thereto.

ARTICLE 6  COVENANTS



The Company shall promptly make all payments in respect of the Securities on the dates and in the manner provided in the Securities and this Indenture. An
installment of principal or interest or Additional Interest, if any, shall be considered paid on the date it is due if the Paying Agent (other than the Company) holds by 11:00 a.m., New York
City time, on that date money, deposited by the Company or an Affiliate thereof, sufficient to pay the installment. The Company shall, (in immediately available funds) to the fullest extent permitted
by law, pay interest on overdue principal (including premium, if any) and overdue installments of interest at the rate borne by the Securities per annum.

Payment
of the principal of (and premium, if any) and any interest on the Securities shall be made at the office or agency of the Company maintained for that purpose in the Borough of
Manhattan, The City of New York (which shall initially be State Street Bank and Trust Company, N.A., an Affiliate of the Trustee, as agent of the Trustee) or at the Corporate Trust Office of the
Trustee in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts;provided, however,that at the option of the Company
payment of interest may be made by check mailed to the address of the Person entitled thereto as such address appears in the Register; provided furtherthat a Holder with an aggregate principal amount
in excess of $2,000,000 will be paid by wire transfer in immediately available funds
at the election of such Holder if such Holder has provided wire transfer instructions to the Company at least 10 Business Days prior to the payment date.



The Company shall file all reports and other information and documents which it is required to file with the SEC pursuant to Section 13 or 15(d) of the
Exchange Act, and within 15 days after it files them with the SEC, the Company shall file copies of all such reports, information and other documents with the Trustee. It is agreed that
delivery of said reports to the Trustee by electronic means shall constitute "filing" of such reports with the Trustee for purposes of this Section 6.2.

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



The Company shall deliver to the Trustee, within 90 days after the end of each fiscal year of the Company (beginning with the fiscal year ending
December 31, 2002), an Officers' Certificate as to the signer's knowledge of the Company's compliance with all conditions and covenants on its part contained in this Indenture and stating
whether or not the signer knows of any default or Event of Default. If such signer knows of such a default or Event of Default, the Officers' Certificate shall describe the default or Event of Default
and the efforts to remedy the same. For the purposes of this

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Section 6.3, compliance shall be determined without regard to any grace period or requirement of notice provided pursuant to the terms of this Indenture.



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.



Subject to Article 7, the Company will do or cause to be done all things necessary to preserve and keep in full force and effect its corporate existence.



Within the period prior to the expiration of the holding period applicable to sales thereof under Rule 144(k) under the Securities Act (or any successor
provision), the Company covenants and agrees that it shall, during any period in which it is not subject to Section 13 or 15(d) under the Exchange Act, upon the request of any Holder or
beneficial holder of the Securities make available to such Holder or
beneficial holder of Securities or any Common Stock issued upon conversion thereof which continue to be Transfer Restricted Securities in connection with any sale thereof and any prospective purchaser
of Securities or such Common Stock designated by such Holder or beneficial holder, the information required pursuant to Rule 144A(d)(4) under the Securities Act or such Common Stock and it will
take such further action as any Holder or beneficial holder of such Securities or such Common Stock may reasonably request, all to the extent required from time to time to enable such Holder or
beneficial holder to sell its Securities or Common Stock without registration under the Securities Act within the limitation of the exemption provided by Rule 144A, as such Rule may be amended
from time to time. Upon the request of any Holder or any beneficial holder of the Securities or such Common Stock, the Company will deliver to such Holder a written statement as to whether it has
complied with such requirements.



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



If Additional Interest is payable by the Company pursuant to the Registration Rights Agreement, the Company shall deliver to the Trustee a certificate to that
effect stating (i) the amount of such Additional Interest that is payable and (ii) the date on which such Additional Interest is payable. Unless and until a Trust Officer of the Trustee
receives such a certificate, the Trustee may assume without inquiry that no such Additional Interest is payable. If the Company has paid Additional

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Interest directly to the Persons entitled to it, the Company shall deliver to the Trustee a certificate setting forth the particulars of such payment.

ARTICLE 7  CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE



The Company shall not consolidate with or merge into any other Person (in a transaction in which the Company is not the surviving corporation) or convey, transfer
or lease its properties and assets substantially as an entirety to any Person, unless:



Upon any consolidation of the Company with, or merger of the Company into, any other Person or any conveyance, transfer or lease of the properties and assets of
the Company substantially as an entirety in accordance with Section 7.1, the successor Person formed by such consolidation or into which the
Company is merged or 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 Person had been named as the Company herein, and thereafter, except in the case of a lease, the predecessor Person shall be relieved of all obligations and covenants
under this Indenture and the Securities.

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ARTICLE 8  DEFAULT AND REMEDIES



An "Event of Default" shall occur if:



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

The
term "Bankruptcy Law" means Title 11 of the United States Code (or any successor thereto) or any similar federal or state law for the relief of debtors. The term "Custodian" means
any receiver, trustee, assignee, liquidator, sequestrator or similar official under any Bankruptcy Law.

A
default under clause (3) above is not an Event of Default until the Trustee notifies the Company, or the Holders of at least 25% in aggregate principal amount of the Securities
then outstanding notify the Company and the Trustee, in writing of the default, and the Company does not cure the default within 60 days after receipt of such notice. The notice given pursuant
to this Section 8.1 must specify the default, demand that it be remedied and state that the notice is a "Notice of Default." When any default under this Section 8.1 is cured, it ceases.

The
Trustee shall not be charged with knowledge of any Event of Default unless written notice thereof shall have been given to a Trust Officer at the Corporate Trust Office of the
Trustee by the Company, a Paying Agent, any Holder or any agent of any Holder.



If an Event of Default (other than an Event of Default specified in clause (7) or (8) of Section 8.1) occurs and is continuing, the Trustee
may, by notice to the Company, or the Holders of at least 25% in aggregate principal amount of the Securities then outstanding may, by notice to the Company and the Trustee, declare all unpaid
principal to the date of acceleration on the Securities then outstanding (if not then due and payable) to be due and payable upon any such declaration, and the same shall become and be immediately due
and payable. If an Event of Default specified in clause (7) or (8) of Section 8.1 occurs, all unpaid principal of the Securities then outstanding shall ipso facto become and be
immediately due and payable without any declaration or other act on the part of the Trustee or any Holder. The Holders of a majority in aggregate principal amount of the Securities then outstanding by
notice to the Trustee may rescind an acceleration and its consequences if (a) all existing Events of Default, other than the nonpayment of the principal of the Securities which has become due
solely by such declaration of acceleration, have been cured or waived; (b) to the extent the payment of such interest is lawful, interest (calculated at the rate per annum borne by the
Securities) on overdue installments of interest and overdue principal, which has become due otherwise than by such declaration of acceleration, has been paid; (c) the rescission would not
conflict with any judgment or
decree of a court of competent jurisdiction; and (d) all payments due to the Trustee and any predecessor Trustee under Section 9.7 have been made. No such rescission shall affect any
subsequent default or impair any right consequent thereto.



If an Event of Default occurs and is continuing, the Trustee may, but shall not be obligated to, pursue any available remedy by proceeding at law or in equity to
collect the payment of the principal of or interest on the Securities or to enforce the performance of any provision of the Securities or this Indenture.

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The
Trustee may maintain a proceeding even if it does not possess any of the Securities or does not produce any of them 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 to the extent permitted by law.



Subject to Sections 8.7 and 11.2, the Holders of a majority in aggregate principal amount of the Securities then outstanding by notice to the Trustee may waive an
existing default or Event of Default and its consequence, except a default or Event of Default in the payment of the principal of, premium, if any, or interest on any Security, a failure by the
Company to convert any Securities into Common Stock in accordance with the provisions of the Note and this Indenture or any default or Event of Default in respect of any provision of this Indenture or
the Securities which, under Section 11.2, cannot be modified or amended without the consent of the Holder of each Security affected. When a default or Event of Default is waived, it is cured
and ceases.



The Holders of a majority in aggregate principal amount of the Securities then outstanding may direct the time, method and place of conducting any proceeding for
any remedy available to the Trustee or exercising any trust or power conferred on it. However, the Trustee may refuse to follow any direction
that conflicts with law or this Indenture, that the Trustee determines may be unduly prejudicial to the rights of another Holder or the Trustee, or that may involve the Trustee in personal liability
unless the Trustee is offered indemnity satisfactory to it;provided, however, that the Trustee may take any other action deemed proper by the Trustee
which is not inconsistent with such direction.



A Holder may not pursue any remedy with respect to this Indenture or the Securities (except actions for payment of overdue principal or interest or for the
conversion of the Securities pursuant to Article 4) unless:



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



Notwithstanding any other provision of this Indenture, the right of any Holder of a Security to receive payment of the principal of and interest on the Security,
on or after the respective due dates expressed in the Security and this Indenture, to convert such Security in accordance with Article 4 and

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to bring suit for the enforcement of any such payment on or after such respective dates or the right to convert, is absolute and unconditional and shall not be impaired or affected without the
consent of the Holder.



If an Event of Default in the payment of principal or interest specified in clause (1) or (2) of Section 8.1 occurs and is continuing, the
Trustee may recover judgment in its own name and as trustee of an express trust against the Company or another obligor on the Securities for the whole amount of principal and accrued interest
remaining unpaid, together with, to the extent that payment of such interest is lawful, interest on overdue principal and on overdue installments of interest, in each case at the rate per annum borne
by the Securities and such further amount as shall be sufficient to cover the costs and expenses of collection, including the reasonable compensation, expenses, disbursements and advances of the
Trustee, its agents and counsel.



The Trustee may file such proofs of claim and other papers or documents as may be necessary or advisable in order to have the claims of the Trustee (including any
claim for the reasonable compensation, expenses, disbursements and advances of the Trustee, its agents and counsel) and the Holders allowed in any judicial proceedings relative to the Company (or any
other obligor on the Securities), its creditors or its property and shall be entitled and empowered to collect and receive any money or other property payable or deliverable on any such claims and to
distribute the same, and any Custodian 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 to the Trustee any amount due to 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 9.7, and to the extent that such payment of the reasonable compensation, expenses, disbursements and advances in any such
proceedings shall be denied for any reason, payment of the same shall be secured by a lien on, and shall be paid out of, any and all distributions, dividends, money, securities and other property
which the Holders may be entitled to receive in such proceedings, whether in liquidation or under any plan of reorganization or arrangement or otherwise. Nothing herein contained shall be deemed to
authorize the Trustee to authorize or consent to, or, on behalf of
any Holder, to authorize, accept or adopt 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.



If the Trustee collects any money pursuant to this Article 8, it shall pay out the money in the following order:

First,
to the Trustee for amounts due under Section 9.7;

Second,
to the holders of Senior Indebtedness to the extent required by Article 5;

Third,
to Holders for amounts due and unpaid on the Securities for principal and interest (including Additional Interest, if any), ratably, without preference or priority of any kind,
according to the amounts due and payable on the Securities for principal and interest (including Additional Interest, if any), respectively; and

Fourth,
the balance, if any, to the Company.

The
Trustee may fix a record date and payment date for any payment to Holders pursuant to this Section 8.10.

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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 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 8.11 does not apply to a suit made by the Trustee, a suit by a Holder pursuant to Section 8.7, or a suit by Holders of more than 10% in aggregate principal amount of the
Securities then outstanding.

ARTICLE 9  TRUSTEE



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

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



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



(d)  No
provision of this Indenture shall require the Trustee to expend or risk its own funds or otherwise incur any financial liability in the performance of any of its
duties hereunder or in the exercise of any of its rights or powers unless the Trustee shall have received adequate indemnity in its opinion against potential costs and liabilities incurred by it
relating thereto.

(e)  Every
provision of this Indenture that in any way relates to the Trustee is subject to subsections (a), (b), (c) and (d) of this Section 9.1.

(f)    The
Trustee shall not be liable for interest on any money received by it except as the Trustee may agree in writing with the Company. Money held in trust by the Trustee
need not be segregated from other funds except to the extent required by law.

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Subject to Section 9.1:

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

(b)  Before
the Trustee acts or refrains from acting, it may require an Officers' Certificate or an Opinion of Counsel, which shall conform to Section 12.4(b). The
Trustee shall not be liable for any action it takes or omits to take in good faith in reliance on such Officers' Certificate or Opinion.

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

(d)  The
Trustee shall not be liable for any action it takes or omits to take in good faith which it believes to be authorized or within its rights or powers.

(e)  The
Trustee may consult with counsel of its selection, and the advice or opinion of such counsel as to matters of law shall be full and complete authorization and
protection in respect of any such action taken, omitted or suffered by it hereunder in good faith and in accordance with the advice or opinion of such 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 or direction of any of the Holders
pursuant to this Indenture, unless such Holders shall have offered to the Trustee security or indemnity satisfactory to the Trustee against the costs, expenses and liabilities which might be incurred
by it in compliance with such request or direction.

(g)  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.

(h)  The
Trustee shall not be deemed to have notice of any Default or Event of Default unless a Trust 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, and such notice references the Securities and this Indenture.

(i)    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.



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 an Affiliate of the
Company with the same rights it would have if it were not Trustee. Any Agent may do the same with like rights. However, the Trustee is subject to Sections 9.10 and 9.11.

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The Trustee makes no representation as to the validity or adequacy of this Indenture or the Securities, it shall not be accountable for the Company's use of the
proceeds from the Securities, and it shall not be responsible for any statement in the Securities other than its certificate of authentication.



If a default or an Event of Default occurs and is continuing and if it is known to the Trustee, the Trustee shall mail to each Securityholder notice of the
default or Event of Default within 90 days after it occurs. However, the Trustee may withhold the notice if and so long as a committee of its Trust Officers in good faith determines that
withholding notice is in the interests of Securityholders, except in the case of a default or an Event of Default in payment of the principal of or interest on any Security.



If such report is required by TIA Section 313, within 60 days after each May 15, beginning with the May 15 following the date of this
Indenture, the Trustee shall mail to each Securityholder a brief report dated as of such May 15 that complies with TIA Section 313(a). The Trustee also shall comply with TIA
Section 313(b)(2) and (c).

A
copy of each report at the time of its mailing to Securityholders shall be mailed to the Company and filed with the SEC and each stock exchange, if any, on which the Securities are
listed. The Company shall notify the Trustee whenever the Securities become listed on any stock exchange or listed or admitted to trading on any quotation system and any changes in the stock exchanges
or quotation systems on which the Securities are listed or admitted to trading and of any delisting thereof.



The Company shall pay to the Trustee from time to time such compensation (as agreed to from time to time by the Company and the Trustee in writing) for its
services (which compensation shall not be limited by any provision of law in regard to the compensation of a trustee of an express trust). The Company shall reimburse the Trustee upon request for all
reasonable disbursements, expenses and advances incurred or made by it. Such expenses may include the reasonable compensation, disbursements and expenses of the Trustee's agents and counsel.

The
Company shall indemnify the Trustee or any predecessor Trustee (which for purposes of this Section 9.7 shall include its officers, directors, employees and agents) for, and
hold it harmless against, any and all loss, liability or expense including taxes (other than taxes based upon, measured by or determined by the income of the Trustee), (including reasonable legal fees
and expenses) incurred by it in connection with the acceptance or administration of its duties under this Indenture or any action or failure to act as authorized or within the discretion or rights or
powers conferred upon the Trustee hereunder including the reasonable costs and expenses of the Trustee and its counsel in defending itself against any claim or liability in connection with the
exercise or performance of any of its powers or duties hereunder. The Trustee shall notify the Company promptly of any claim asserted against the Trustee for which it may seek indemnity. The Company
need not pay for any settlement without its written consent, which shall not be unreasonably withheld.

The
Company need not reimburse the Trustee for any expense or indemnify it against any loss or liability incurred by it resulting from its gross negligence or bad faith.

To
secure the Company's payment obligations in this Section 9.7, the Trustee shall have a senior claim to which the Securities are hereby made subordinate on all money or property
held or collected by the Trustee, except such money or property held in trust to pay the principal of and interest on the

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Securities. The obligations of the Company under this Section 9.7 shall survive the satisfaction and discharge of this Indenture or the resignation or removal of the Trustee.

When
the Trustee incurs expenses or renders services after an Event of Default specified in clause (7) or (8) of Section 8.1 occurs, the expenses and the
compensation for the services are intended to constitute expenses of administration under any Bankruptcy Law. The provisions of this Section shall survive the termination of this Indenture.



The Trustee may resign by so notifying the Company. The Holders of a majority in aggregate principal amount of the Securities then outstanding may remove the
Trustee by so notifying the Trustee and may, with the Company's written consent, appoint a successor Trustee. The Company may remove the Trustee if:



If
the Trustee resigns or is removed or if a vacancy exists in the office of Trustee for any reason, the Company shall promptly appoint a successor Trustee. The resignation or removal of
a Trustee shall not be effective until a successor Trustee shall have delivered the written acceptance of its appointment as described below.

If
a successor Trustee does not take office within 45 days after the retiring Trustee resigns or is removed, the retiring Trustee, the Company or the Holders of 10% in principal
amount of the Securities then outstanding may petition any court of competent jurisdiction for the appointment of a successor Trustee at the expense of the Company.

If
the Trustee fails to comply with Section 9.10, any Holder may petition any court of competent jurisdiction for the removal of the Trustee and the appointment of a successor
Trustee.

A
successor Trustee shall deliver a written acceptance of its appointment to the retiring Trustee and to the Company. Immediately after that, the retiring Trustee shall transfer all
property held by it as Trustee to the successor Trustee and be released from its obligations (exclusive of any liabilities that the retiring Trustee may have incurred while acting as Trustee)
hereunder, 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. A
successor Trustee shall mail notice of its succession to each Holder.

A
retiring Trustee shall not be liable for the acts or omissions of any successor Trustee after its succession.

Notwithstanding
replacement of the Trustee pursuant to this Section 9.8, the Company's obligations under Section 9.7 shall continue for the benefit of the retiring Trustee.



If the Trustee consolidates with, merges or converts into, or transfers all or substantially all of its corporate trust assets (including the administration of
this Indenture) to, another corporation, the resulting, surviving or transferee corporation, without any further act, shall be the successor Trustee, provided such transferee corporation shall qualify
and be eligible under Section 9.10. Such successor Trustee shall promptly mail notice of its succession to the Company and each Holder.

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The Trustee shall always satisfy the requirements of paragraphs (1), (2) and (5) of TIA Section 310(a). The Trustee (or its parent holding
company) shall have a combined capital and surplus of at least $50,000,000. If at any time the Trustee shall cease to satisfy any such requirements, it shall resign immediately in the manner and with
the effect specified in this Article 9. The Trustee shall be subject to the provisions of TIA Section 310(b). Nothing herein shall prevent the Trustee from filing with the SEC the
application referred to in the penultimate paragraph of TIA Section 310(b).



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 10  SATISFACTION AND DISCHARGE OF INDENTURE



This Indenture shall cease to be of further effect (except as to any surviving rights of conversion, registration of transfer or exchange of Securities herein
expressly provided for and except as further provided below), and the Trustee, on demand of and at the expense of the Company, shall execute proper instruments acknowledging satisfaction and discharge
of this Indenture, when



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Notwithstanding
the satisfaction and discharge of this Indenture, the obligations of the Company to the Trustee under Section 9.7 shall survive and, if money shall have been
deposited with the Trustee pursuant to subclause (B) of clause (1) of this Section, the provisions of Sections 2.3, 2.4, 2.5, 2.6, 2.7, 2.12, 3.9, 3.10, 3.11, 3.12, 3.13, 3.14 and 12.5,
Article 4, the last paragraph of Section 6.2 and this Article 10, shall survive until the Securities have been paid in full.



Subject to the provisions of Section 10.3, the Trustee or a Paying Agent shall hold in trust, for the benefit of the Holders, all money deposited with it
pursuant to Section 10.1 and shall apply the deposited money in accordance with this Indenture and the Securities to the payment of the principal of and interest on the Securities. Money so
held in trust shall not be subject to the subordination provisions of Article 5.



The Trustee and each Paying Agent shall promptly pay to the Company upon request any excess money (i) deposited with them pursuant to Section 10.1
and (ii) held by them at any time.

The
Trustee and each Paying Agent shall pay to the Company upon request any money held by them for the payment of principal or interest that remains unclaimed for two years after a right
to such money has matured;provided, however,that the Trustee or such Paying Agent, before being required to make any such payment, may at the expense
of the Company cause to be mailed to each Holder entitled to such money notice that such money remains unclaimed and that after a date specified therein, which shall be at least 30 days from
the date of such mailing, any unclaimed balance of such money then remaining will be repaid to the Company. After payment to the Company, Holders entitled to money must look to the Company for payment
as general creditors unless an applicable abandoned property law designates another person.



If the Trustee or any Paying Agent is unable to apply any money in accordance with Section 10.2 by reason of any legal proceeding or by reason of any order
or judgment of any court or governmental authority enjoining, restraining or otherwise prohibiting such application, then the Company's obligations under this Indenture and the Securities shall be
revived and reinstated as though no deposit had occurred pursuant to Section 10.1 until such time as the Trustee or such Paying Agent is permitted to apply all such money in accordance with
Section 10.2;provided, however,that if the Company has made any payment of the principal of or interest on any Securities because of the
reinstatement of its obligations, the Company shall be subrogated to the rights of the Holders of such Securities to receive any such payment from the money held by the Trustee or such Paying Agent.

ARTICLE 11  AMENDMENTS, SUPPLEMENTS AND WAIVERS



The Company and the Trustee may amend or supplement this Indenture or the Securities without notice to or consent of any Securityholder:

(a)  to
comply with Sections 4.11 and 7.1;

(b)  to
cure any ambiguity, defect or inconsistency;

(c)  to
make any other change that does not adversely affect the rights of any Securityholder;

(d)  to
comply with the provisions of the TIA;

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(e)  to
add to the covenants of the Company for the equal and ratable benefit of the Securityholders or to surrender any right, power or option conferred upon the Company; or

(f)    to
appoint a successor Trustee.



The Company and the Trustee may amend or supplement this Indenture or the Securities with the written consent of the Holders of at least a majority in aggregate
principal amount of the Securities then outstanding. The Holders of at least a majority in aggregate principal amount of the Securities then outstanding may waive compliance in a particular instance
by the Company with any provision of this Indenture or the Securities without notice to any Securityholder. However, notwithstanding the foregoing but subject to Section 11.4, without the
written consent of each Securityholder affected, an amendment, supplement or waiver, including a waiver pursuant to Section 8.4, may not:

(a)  change
the stated maturity of the principal of, or interest on, any Security;

(b)  reduce
the principal amount of, or any premium or interest on, any Security;

(c)  reduce
the amount of principal payable upon acceleration of the maturity of any Security;

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

(e)  impair
the right to institute suit for the enforcement of any payment on, or with respect to, any Security;

(f)    modify
the provisions with respect to the purchase right of Holders pursuant to Article 3 upon a Change in Control in a manner adverse to Holders;

(g)  modify
the subordination provisions of Article 5 in a manner materially adverse to the Holders of Securities;

(h)  adversely
affect the right of Holders to convert Securities other than as provided in or under Article 4 of this Indenture;

(i)    reduce
the percentage of the aggregate principal amount of the outstanding Securities whose Holders must consent to a modification or amendment;

(j)    reduce
the percentage of the aggregate principal amount of the outstanding Securities necessary for the waiver of compliance with certain provisions of this Indenture or
the waiver of certain defaults under this Indenture; and

(k)  modify
any of the provisions of this Section or Section 8.4, except to increase any such percentage or to provide that certain provisions of this Indenture cannot
be modified or waived without the consent of the Holder of each outstanding Security affected thereby.

It
shall not be necessary for the consent of the Holders under this Section 11.2 to approve the particular form of any proposed amendment, supplement or waiver, but it shall be
sufficient if such consent approves the substance thereof.

After
an amendment, supplement or waiver under this Section 11.2 becomes effective, the Company shall mail to the Holders affected thereby a notice briefly describing the
amendment, supplement or waiver. Any failure of the Company to mail such notice, or any defect therein, shall not, however, in any way impair or affect the validity of any such amendment, supplement
or waiver. An amendment or supplement under this Section 11.2 or under Section 11.1 may not make any change that adversely affects the rights under Article 5 of any holder of an
issue of Senior Indebtedness unless the holders of that issue, pursuant to its terms, consent to the change.

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To
the extent that the Company or any of the Subsidiaries hold any Securities, such Securities shall be disregarded for purposes of voting in connection with any notice, waiver, consent
or direction requiring the vote or concurrence of Securityholders.



Every amendment to or supplement of this Indenture or the Securities shall comply with the TIA as in effect at the date of such amendment or supplement.



Until an amendment, supplement or waiver becomes effective, a consent to it by a Holder is a continuing consent by the Holder and every subsequent Holder of a
Security or portion of a Security that evidences the same debt as the consenting Holder's Security, even if notation of the consent is not made on any Security. However, any such Holder or subsequent
Holder may revoke the consent as to its Security or portion of a Security if the Trustee receives the notice of revocation before the date the amendment, supplement or waiver becomes effective.

After
an amendment, supplement or waiver becomes effective, it shall bind every Securityholder, unless it makes a change described in any of clauses (a) through (k) of
Section 11.2. In that case the amendment, supplement or waiver shall bind each Holder of a Security who has consented to it and every subsequent Holder of a Security or portion of a Security
that evidences the same debt as the consenting Holder's Security.



If an amendment, supplement or waiver changes the terms of a Security, the Trustee may require the Holder of the Security to deliver it to the Trustee. The
Trustee may place an appropriate notation on the Security about the changed terms and return it to the Holder. Alternatively, if the Company or the Trustee so determines, the Company in exchange for
the Security shall issue and the Trustee shall authenticate a new Security that reflects the changed terms.



The Trustee shall sign any amendment or supplemental indenture authorized pursuant to this Article 11 if the amendment or supplemental indenture does not
adversely affect the rights, duties, liabilities or immunities of the Trustee. If it does, the Trustee may, in its sole discretion, but need not sign it. In signing or refusing to sign such amendment
or supplemental indenture, the Trustee shall be entitled to receive and, subject to Section 9.1, shall be fully protected in relying upon, an Opinion of Counsel stating that such amendment or
supplemental indenture is authorized or permitted by this Indenture. The Company may not sign an amendment or supplement indenture until the Board of Directors approves it.



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.

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ARTICLE 12  MISCELLANEOUS



If any provision of this Indenture limits, qualifies or conflicts with the duties imposed by any of Sections 310 to 317, inclusive, of the TIA through operation
of Section 318(c) thereof, such imposed duties shall control.



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



Such
notices or communications shall be effective when received.

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

Any
notice or communication mailed to a Securityholder shall be mailed by first-class mail or delivered by an overnight delivery service to it at its address shown on the register kept
by the Primary Registrar.

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 to
a Securityholder is mailed in the manner provided above, it is duly given, whether or not the addressee receives it.

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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 and any other person shall have the protection of TIA Section 312(c).



(a)  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 at the request of the
Trustee:



(b)  Each
Officers' Certificate and Opinion of Counsel with respect to compliance with a condition or covenant provided for in this Indenture shall include:



provided however,that with respect to matters of fact an Opinion of Counsel may rely on an Officers' Certificate or certificates of public officials.



The Company (or, in the event deposits have been made pursuant to Section 10.1, the Trustee) may set a record date for purposes of determining the identity
of Holders entitled to vote or consent to any action by vote or consent authorized or permitted under this Indenture, which record date shall not be more than thirty (30) days prior to the date
of the commencement of solicitation of such action. Notwithstanding the provisions of Section 11.4, if a record date is fixed, those persons who were Holders of Securities at the close of
business on such record date (or their duly designated proxies), and only those persons, shall be entitled to take such action by vote or consent or to revoke any vote or consent previously given,
whether or not such persons continue to be Holders after such record date.



The Trustee may make reasonable rules (not inconsistent with the terms of this Indenture) for action by or at a meeting of Holders. Any Registrar, Paying Agent or
Conversion Agent may make reasonable rules for its functions.

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A "Legal Holiday" is a Saturday, Sunday or a day on which state or federally chartered banking institutions in New York, New York and the state in which the
Corporate Trust Office is located are not required to be open. If a payment date is a Legal Holiday, payment shall be made on the next succeeding day that is not a Legal Holiday, and no interest shall
accrue for the intervening period. If a regular record date is a Legal Holiday, the record date shall not be affected.



This Indenture and the Securities shall be governed by, and construed in accordance with, the laws of the State of New York.



This Indenture may not be used to interpret another indenture, loan or debt agreement of the Company or a Subsidiary of the Company. Any such indenture, loan or
debt agreement may not be used to interpret this Indenture.



All liability described in paragraph 19 of the Securities of any director, officer, employee or shareholder, as such, of the Company is waived and
released.



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.



The parties may sign multiple counterparts of this Indenture. Each signed counterpart shall be deemed an original, but all of them together represent the same
agreement.



In case any provisions 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.



The table of contents, cross-reference sheet and headings of the Articles and Sections of this Indenture have been inserted for convenience of reference only, are
not to be considered a part hereof, and shall in no way modify or restrict any of the terms or provisions hereof.

[SIGNATURE
PAGE FOLLOWS]

55

---

IN
WITNESS WHEREOF, the parties hereto have hereunto set their hands as of the date and year first above written.

| | Abgenix, Inc.                                                      
| | -------------------------------------------------------------------
| | By:                                                                
| | Name:                                                              
| | Title:                                                             
| | State Street Bank and Trust Company of California, N.A., as Trustee
| | By:                                                                
| | Name:                                                              
| | Title:                                                             

56

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EXHIBIT A  [FORM OF FACE OF SECURITY]

[UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF
TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF 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. THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE
INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITARY OR A NOMINEE THEREOF. THIS SECURITY IS EXCHANGEABLE FOR SECURITIES REGISTERED IN THE NAME OF A PERSON OTHER THAN THE
DEPOSITARY OR ITS NOMINEE ONLY IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE AND, UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR SECURITIES IN DEFINITIVE FORM, THIS SECURITY MAY
NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR
ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY.]1

[THIS
SECURITY (OR ITS PREDECESSOR) WAS ORIGINALLY ISSUED IN A TRANSACTION EXEMPT FROM REGISTRATION UNDER THE UNITED STATES SECURITIES ACT OF 1933 (THE "SECURITIES ACT"), AND
THIS SECURITY AND THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION THEREOF MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR AN APPLICABLE EXEMPTION
THEREFROM. EACH PURCHASER OF THIS SECURITY IS HEREBY NOTIFIED THAT THE SELLER OF THIS SECURITY MAY BE RELYING ON THE EXEMPTION FROM THE PROVISIONS OF SECTION 5 OF THE SECURITIES ACT PROVIDED BY
RULE 144A THEREUNDER.]2

THE
HOLDER OF THIS SECURITY AGREES FOR THE BENEFIT OF THE COMPANY THAT (A) THIS SECURITY AND THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION THEREOF MAY BE OFFERED, RESOLD,
PLEDGED OR OTHERWISE TRANSFERRED, ONLY (I) IN THE UNITED STATES TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER (AS DEFINED IN RULE 144A UNDER THE SECURITIES
ACT) IN A TRANSACTION MEETING THE REQUIREMENTS OF RULE 144A, (II) OUTSIDE THE UNITED STATES IN AN OFFSHORE TRANSACTION IN ACCORDANCE WITH RULE 904 UNDER THE SECURITIES ACT,
(III) PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT PROVIDED BY RULE 144 THEREUNDER (IF AVAILABLE) OR (IV) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE
SECURITIES ACT, IN EACH OF CASES (I) THROUGH (IV) IN ACCORDANCE WITH ANY APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES, AND (B) THE HOLDER WILL, AND EACH SUBSEQUENT
HOLDER IS REQUIRED TO, NOTIFY ANY PURCHASER OF THIS SECURITY FROM IT OF THE RESALE RESTRICTIONS REFERRED TO IN (A) ABOVE. IN ANY CASE,

A-1

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THE HOLDER HEREOF WILL NOT, DIRECTLY OR INDIRECTLY, ENGAGE IN ANY HEDGING TRANSACTIONS WITH REGARD TO THE SECURITIES EXCEPT AS PERMITTED UNDER THE SECURITIES ACT.]2

[THE
HOLDER OF THIS SECURITY IS ENTITLED TO THE BENEFITS OF A REGISTRATION RIGHTS AGREEMENT (AS SUCH TERM IS DEFINED IN THE INDENTURE REFERRED TO ON THE REVERSE HEREOF) AND,
BY ITS ACCEPTANCE HEREOF, AGREES TO BE BOUND BY AND TO COMPLY WITH THE PROVISIONS OF SUCH REGISTRATION RIGHTS AGREEMENT.]2

A-2

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ABGENIX, INC.

CUSIP
No.: 00339B AA 5

31/2% CONVERTIBLE SUBORDINATED NOTES DUE 2007

Abgenix, Inc., a Delaware corporation (the "Company", which term shall include any successor corporation under the Indenture referred to on the reverse
hereof), promises to pay to Cede & Co., or registered assigns, the principal sum of Two Hundred Million Dollars ($200,000,000.00) on March, 15, 2007, or such greater or lesser amount as is
indicated on the Schedule of Exchanges of Notes on the other side of this Note.

|Interest Payment Dates: |  | March 15 and September 15, commencing September 15, 2002
|----------------------- |  | --------------------------------------------------------
|Record Dates:           |  | March 1 and September 1                                 

This
Note is convertible as specified on the other side of this Note. Additional provisions of this Note are set forth on the other side of this Note.

SIGNATURE
PAGE FOLLOWS

A-3

---

IN
WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

|             | ABGENIX, INC.
|------------ | -------------
|             | By:          
|             | Name:        
|             | Title:       
|Attest:      |              
|Name: Title: |              
|Dated:       |              

TRUSTEE'S CERTIFICATE OF AUTHENTICATIONThis is one of the Securities referred to
in the within-mentioned Indenture.

|State Street Bank And Trust Company of California, N.A.,as Trustee
|------------------------------------------------------------------
|Authorized Signatory                                              

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EXHIBIT B

CERTIFICATE TO BE DELIVERED UPON EXCHANGE OR REGISTRATION
OF TRANSFER OF TRANSFER RESTRICTED SECURITIES4

|Re: |  | 31/2% Convertible Subordinated Notes due 2007 (the "Notes") of Abgenix, Inc.                      
|--- |  | --------------------------------------------------------------------------------------------------
|    |  | This certificate relates to $            principal amount of Notes owned in (check applicable box)
|    |  | o  book-entry or o  definitive form
by                        (the "Transferor").                 

The
Transferor has requested a Registrar or the Trustee to exchange or register the transfer of such Notes.

In
connection with such request and in respect of each such Note, the Transferor does hereby certify that the Transferor is familiar with transfer restrictions relating to the Notes as
provided in Section 2.12 of the Indenture dated as of March 4, 2002 between Abgenix, Inc. and State Street Bank and Trust
Company of California, N.A., as trustee (the "Indenture"), and the transfer of such Note is being made pursuant to an effective registration statement under the Securities Act of 1933, as amended (the
"Securities Act") (check applicable box) or the transfer or exchange, as the case may be, of such Note does not require registration under the Securities Act because (check applicable box):

| |  | o |  | Such Note is being transferred pursuant to an effective registration statement under the Securities Act.                                                                                                                                                                                                                                                                                                                                                                   
| |  | - |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| |  | o |  | Such Note is being transferred outside the United States in an offshore transaction in accordance with Rule 904 under the Securities Act.                                                                                                                                                                                                                                                                                                                                  
| |  | o |  | Such Note is being acquired for the Transferor's own account, without transfer.                                                                                                                                                                                                                                                                                                                                                                                            
| |  | o |  | Such Note is being transferred to the Company or a Subsidiary (as defined in the Indenture) of the Company.                                                                                                                                                                                                                                                                                                                                                                
| |  | o |  | Such Note is being transferred to a person the Transferor reasonably believes is a "qualified institutional buyer" (as defined in Rule 144A or any successor provision thereto ("Rule 144A") under the Securities Act) that is purchasing for
its own account or for the account of a "qualified institutional buyer", in each case to whom notice has been given that the transfer is being made in reliance on such Rule 144A, and in each case in reliance on Rule 144A.
| |  | o |  | Such Note is being transferred pursuant to and in compliance with an exemption from the registration requirements under the Securities Act in accordance with Rule 144 (or any successor thereto) ("Rule 144") under the Securities
Act.                                                                                                                                                                                                                                   

Such
Note is being transferred pursuant to and in compliance with an exemption from the registration requirements of the Securities Act (other than an exemption referred to above) and as
a result of which such Note will, upon such transfer, cease to be a "restricted security" within the meaning of Rule 144 under the Securities Act.

The
Transferor acknowledges and agrees that, if the transferee will hold any such Notes in the form of beneficial interests in a global Note which is a "restricted security" within the
meaning of Rule 144 under the Securities Act, then such transfer can only be made pursuant to Rule 144A under the Securities Act and such transferee must be a "qualified institutional
buyer" (as defined in Rule 144A).

|Date: |  |  |  |                            
|----- |  |  |  | ---------------------------
|      |  |  |  | (Insert Name of Transferor)

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[FORM OF REVERSE SIDE OF SECURITY]

ABGENIX, INC.
31/2% CONVERTIBLE SUBORDINATED NOTES DUE 2007

1. INTEREST

Abgenix, Inc.,
a Delaware corporation (the "Company", which term shall include any successor corporation under the Indenture hereinafter referred to), promises to pay interest on
the principal amount of this Note at the rate of 31/2% per annum. The Company shall pay interest semiannually on March 15 and September 15 of each year, commencing on
September 15, 2002. Interest on the Notes shall accrue from the most recent date to which interest has been paid or, if no interest has been paid, from March 4, 2002; provided, however,that
if there is not an existing default in the payment of interest and if this Note is authenticated between a record date referred
to on the face hereof and the next succeeding interest payment date, interest shall accrue from such interest payment date. Interest will be computed on the basis of a 360-day year of
twelve 30-day months.

2. REGISTRATION RIGHTS AGREEMENT

The
holder of this Note is entitled to the benefits of a Registration Rights Agreement, dated as of March 4, 2002, among the Company and the Initial Purchasers (the "Registration
Rights Agreement"). Pursuant to the Registration Rights Agreement the Company has agreed for the benefit of the Holders
of the Notes, that (i) it will, at its cost, within 90 days after the closing of the sale of the Notes (the "Closing"), file a shelf registration statement (the "Shelf
Registration Statement") with the Securities and Exchange Commission (the "Commission") with respect to resales of the Notes and the Common Stock issuable upon conversion thereof, (ii) it will
use commercially reasonable efforts to cause such Shelf Registration Statement to be declared effective within 180 days after the Closing, and (iii) it will use commercially reasonable
efforts to keep such Shelf Registration Statement continuously effective under the Securities Act, subject to certain exceptions specified in the Registration Rights Agreement, until the second
anniversary of the date of the Closing. If (a) the Company fails to file the Shelf Registration Statement required by the Registration Rights Agreement on or before the date specified above for
such filing, (b) such Shelf Registration Statement is not declared effective by the Commission on or prior to the date specified above for such effectiveness, or (c) the Shelf
Registration Statement is declared effective but thereafter ceases to be effective or useable in connection with resales of Transfer Restricted Securities (as defined in the Registration Rights
Agreement), other than for a permitted suspension as described in this Section 2, during the periods specified in the Registration Rights Agreement (each such event referred to in clauses
(a) through (c) above a "Registration Default"), then the Company will pay Additional Interest to each Holder of Transfer Restricted Securities, in an amount equal to an increase in the
annual interest rate on the Notes of 0.50% ("Additional Interest") until all Registration Defaults have been cured. All accrued Additional Interest shall be paid by the Company on each Interest
Payment Date for which Additional Interest is owed to the holders of Global Notes by wire transfer of immediately available funds or by federal funds check and to holders of certificated Notes
registered as such as of the preceding Record Date by mailing checks to their registered addresses. The Company will be permitted to suspend the effectiveness of the Shelf Registration Statement for
up to 45 consecutive days in any 90-day period, and for up to a total of 90 days in any 365-day period, without being required to pay Additional Interest. Following the
cure of all Registration Defaults, the application of Additional Interest will cease.

3. METHOD OF PAYMENT

The
Company shall pay interest on this Note (except defaulted interest) to the person who is the Holder of this Note at the close of business on March 1 or September 1, as
the case may be, next

B-2

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preceding the related interest payment date. The Holder must surrender this Note to a Paying Agent to collect payment of principal. The Company will pay principal and interest in money of the United
States that at the time of payment is legal tender for payment of public and private debts. The Company may, however, pay principal and interest in respect of any Certificated Security by check or
wire payable in such money;provided, however,that a Holder with an aggregate principal amount in excess of $2,000,000 will be paid by wire transfer in
immediately available funds at the election of such Holder if such Holder has provided wire transfer instructions to the Company at least 10 Business Days prior to the payment date.

4. PAYING AGENT, REGISTRAR AND CONVERSION AGENT

Initially,
State Street Bank and Trust Company of California, N.A. (the "Trustee", which term shall include any successor trustee under the Indenture hereinafter referred to) will act as
Paying Agent,
Registrar and Conversion Agent. The Company may change any Paying Agent, Registrar or Conversion Agent without notice to the Holder. The Company or any of its Subsidiaries may, subject to certain
limitations set forth in the Indenture, act as Paying Agent or Registrar.

5. INDENTURE, LIMITATIONS

This
Note is one of a duly authorized issue of Securities of the Company designated as its 31/2% Convertible Subordinated Notes due 2007 (the "Notes"), issued under an
Indenture dated as of March 4, 2002 (together with any supplemental indentures thereto, the "Indenture"), between the Company and the Trustee. The terms of this Note include those stated in the
Indenture and those required by or made part of the Indenture by reference to the Trust Indenture Act of 1939, as amended, as in effect on the date of the Indenture. This Note is subject to all such
terms, and the Holder of this Note is referred to the Indenture and said Act for a statement of them. The Notes are subordinated unsecured obligations of the Company limited to $250,000,000 aggregate
principal amount. The Indenture does not limit other debt of the Company, secured or unsecured, including Senior Indebtedness.

6. PROVISIONAL AND OPTIONAL REDEMPTION

This
Note may be redeemed at the election of the Company, as a whole or in part from time to time, at any time prior to March 20, 2005 (a "Provisional Redemption"), upon at least
20 and not more than 60 days' notice by mail to the Holders of the Notes at a redemption price equal to $1,000 per $1,000 principal amount of the Notes redeemed plus accrued and unpaid
interest, if any (such amount, together with the Make-Whole Payment described below, the "Provisional Redemption Price"), to but excluding the date of redemption (the "Provisional
Redemption Date") if (1) the Closing Price of the Common Stock has exceeded 150% of the then applicable Conversion Price for at least 20 Trading Days within a period of any 30 consecutive
Trading Days ending on the Trading Day prior to the date of mailing of the notice of Provisional Redemption (the "Provisional Redemption Notice Date"), and (2) a shelf registration statement
covering resales of the Notes and the Common Stock issuable upon conversion thereof is effective and available for use in accordance with the Registration Rights Agreement and is expected to remain
effective and available for use for the 30 days following the Provisional Redemption Date unless registration is no longer required.

Upon
any such Provisional Redemption, the Company, shall make an additional payment, at its option, in cash or Common Stock or a combination of cash and Common Stock (the "Make Whole
Payment") with respect to the Notes called for redemption to holders on the Provisional Redemption Notice Date in an amount equal to $                  105.00
per $1,000 principal amount of the Notes,
less the amount of any interest actually paid (including, if the Provisional Redemption Date occurs after a record date but before an interest payment date, any interest paid or payable in connection
with such interest payment date) on such Notes prior to the Provisional Redemption Date. Payments made in

B-3

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Common Stock will be valued at 97% of the average Closing Price of Common Stock for the five Trading Days ending on the day prior to the Redemption Date. The Company shall make the
Make-Whole Payment on all Notes called for Provisional Redemption, including those Notes converted into Common Stock between the Provisional Redemption Notice Date and the Provisional
Redemption Date.

Except
as set forth above, the Notes are subject to redemption, at any time on or after March 20, 2005, on at least 20 days and no more than 60 days notice, in whole
or in part, at the election of the Company. The Redemption Prices (expressed as percentages of the principal amount) are as follows for Notes redeemed during the periods set forth below:

|Period                                |  | Redemption Price
|------------------------------------- |  | ----------------
|March 20, 2005 through March 14, 2006 |  | 100.875%        
|March 15, 2006 and thereafter         |  | 100.000%        

in
each case together with accrued interest up to but not including the Redemption Date; provided that if the redemption date is an interest payment date, interest will be payable to the Holders in
whose names the Notes are registered at the close of business on the relevant record dates.

No
sinking fund is provided for the Notes.

7. NOTICE OF REDEMPTION

Notice
of redemption will be mailed by first-class mail at least 20 days but not more than 60 days before the Redemption Date to each Holder of Notes to be redeemed at its
registered address. Notes in denominations larger than $1,000 may be redeemed in part, but only in whole multiples of $1,000. On and after the Redemption Date, subject to the deposit with the Paying
Agent of funds sufficient to pay the Redemption Price plus accrued interest, if any, accrued to, but excluding, the Redemption Date, interest shall cease to accrue on Notes or portions of them called
for redemption.

8. PURCHASE OF NOTES AT OPTION OF HOLDER UPON A CHANGE IN CONTROL

At
the option of the Holder and subject to the terms and conditions of the Indenture, the Company shall become obligated to purchase all or any part specified by the Holder (so long as
the principal amount of such part is $1,000 or an integral multiple of $1,000 in excess thereof) of the Notes held by such Holder on the date that is 30 Business Days after the occurrence of a Change
in Control, at a purchase price equal to 100% of the principal amount thereof together with accrued interest up to, but excluding, the Change in Control Purchase Date. The Holder shall have the right
to withdraw any Change in Control Purchase Notice (in whole or in a portion thereof that is $1,000 or an integral multiple of $1,000 in excess thereof) at any time prior to the close of business on
the second Business Day next preceding the Change in Control Purchase Date by delivering a written notice of withdrawal to the Paying Agent in accordance with the terms of the Indenture.

9. CONVERSION

A
Holder of a Note may convert the principal amount of such Note (or any portion thereof equal to $1,000 or any integral multiple of $1,000 in excess thereof) into Common Stock at any
time prior to the close of business on the Final Maturity Date, at the Conversion Price then in effect; provided, however, that, if such Note is called for redemption or submitted or presented for
purchase pursuant to Article 3 of the Indenture, such conversion right shall terminate at the close of business on the Business Day immediately preceding the Redemption Date or Change in
Control Purchase Date, as the case may be, for such Note or such earlier date as the Holder presents such Security for redemption or for purchase (unless the Company shall default in making the
redemption payment or Change in

B-4

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Control Purchase Price payment when due, in which case the conversion right shall terminate at the close of business on the date such default is cured and such Note is redeemed or purchased, as the
case may be).

The
initial Conversion Price is $27.58 per share, subject to adjustment under certain circumstances as provided in the Indenture. The number of shares of Common Stock issuable upon
conversion of a Note is determined by dividing the principal amount of the Note or portion thereof converted by the Conversion Price in effect on the Conversion Date. No fractional shares will be
issued upon conversion; in lieu thereof, an amount will be paid in cash based upon the Closing Price (as defined in the Indenture) of the Common Stock on the Trading Day immediately prior to the
Conversion Date.

To
convert a Note, a Holder must (a) complete and manually sign the conversion notice set forth below and deliver such notice to a Conversion Agent, (b) surrender the Note
to a Conversion Agent, (c) furnish appropriate endorsements and transfer documents if required by a Registrar or a Conversion Agent, and (d) pay any transfer or similar tax, if required.
Notes so surrendered for conversion (in whole or in part) during the period from the close of business on any regular record date to the opening of business on the next succeeding interest payment
date (excluding Notes or portions thereof called for redemption or subject to purchase upon a Change in Control on a Redemption Date or
Change in Control Purchase Date, as the case may be, during the period beginning at the close of business on a regular record date and ending at the opening of business on the first Business Day after
the next succeeding interest payment date, or if such interest payment date is not a Business Day, the second such Business Day) shall also be accompanied by payment in funds acceptable to the Company
of an amount equal to the interest payable on such interest payment date on the principal amount of such Note then being converted, and such interest shall be payable to such registered Holder
notwithstanding the conversion of such Note, subject to the provisions of this Indenture relating to the payment of defaulted interest by the Company. If the Company defaults in the payment of
interest payable on such interest payment date, the Company shall promptly repay such funds to such Holder. A Holder may convert a portion of a Note equal to $1,000 or any integral multiple thereof.

A
Note in respect of which a Holder had delivered a Change in Control Purchase Notice exercising the option of such Holder to require the Company to purchase such Note may be converted
only if the Change in Control Purchase Notice is withdrawn in accordance with the terms of the Indenture.

10. CONVERSION ARRANGEMENT ON CALL FOR REDEMPTION

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

11. SUBORDINATION

The
indebtedness evidenced by the Notes is, to the extent and in the manner provided in the Indenture, subordinate and junior in right of payment to the prior payment in full of all
Senior Indebtedness of the Company. Any Holder by accepting this Note agrees to and shall be bound by such subordination provisions and authorizes the Trustee to give them effect. In addition to all
other rights of Senior Indebtedness described in the Indenture, the Senior Indebtedness shall continue to be Senior Indebtedness and entitled to the benefits of the subordination provisions
irrespective of any

B-5

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amendment, modification or waiver of any terms of any instrument relating to the Senior Indebtedness or any extension or renewal of the Senior Indebtedness.

12. DENOMINATIONS, TRANSFER, EXCHANGE

The
Notes are in registered form, without coupons, in denominations of $1,000 and integral multiples of $1,000. A Holder may register the transfer of or exchange Notes 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 or other governmental charges that may be imposed
in relation thereto by law or permitted by the Indenture.

13. PERSONS DEEMED OWNERS

The
Holder of a Note may be treated as the owner of it for all purposes.

14. UNCLAIMED MONEY

If
money for the payment of principal or interest remains unclaimed for two years, the Trustee or Paying Agent will pay the money back to the Company at its written request, subject to
applicable unclaimed property law. After that, Holders entitled to money must look to the Company for payment as general creditors unless an applicable abandoned property law designates another
person.

15. AMENDMENT, SUPPLEMENT AND WAIVER

Subject
to certain exceptions, the Indenture or the Notes may be amended or supplemented with the consent of the Holders of at least a majority in aggregate principal amount of the Notes
then outstanding, and an existing default or Event of Default and its consequence or compliance with any provision of the Indenture or the Notes may be waived in a particular instance with the consent
of the Holders of a majority in aggregate principal amount of the Notes then outstanding. Without the consent of or notice to any Holder, the Company and the Trustee may amend or supplement the
Indenture or the Notes to, among other things, cure any ambiguity, defect or inconsistency or make any other change that does not adversely affect the rights of any Holder.

16. SUCCESSOR ENTITY

When
a successor corporation assumes all the obligations of its predecessor under the Notes and the Indenture in accordance with the terms and conditions of the Indenture, the
predecessor corporation (except in certain circumstances specified in the Indenture) shall be released from those obligations.

17. DEFAULTS AND REMEDIES

Under
the Indenture, an Event of Default includes: (i) default for 30 days in payment of any interest or Additional Interest on any Notes; (ii) default in payment of
any principal (including, without limitation, any premium, if any) on the Notes when due; (iii) failure by the Company for 60 days after notice to it to comply with any of its other
agreements contained in the Indenture or the Notes; (iv) default in the payment of certain indebtedness of the Company or a Significant Subsidiary; (v) the Company fails to provide a
Purchase Offer within 30 days after notice of failure to timely deliver the same; and (vi) certain events of bankruptcy, insolvency or reorganization of the Company or any Significant
Subsidiary. If an Event of Default (other than as a result of certain events of bankruptcy, insolvency or reorganization of the Company) occurs and is continuing, the Trustee or the Holders of at
least 25% in aggregate principal amount of the Notes then outstanding may declare all unpaid principal to the date of acceleration on the Notes then outstanding to be due and payable immediately, all
as and to the extent provided in the Indenture. If an Event of Default occurs as a result of certain

B-6

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events of bankruptcy, insolvency or reorganization of the Company, unpaid principal of the Notes then outstanding shall become due and payable immediately without any declaration or other act on the
part of the Trustee or any Holder, all as and to the extent provided in the Indenture. Holders may not enforce the Indenture or the Notes except as provided in the Indenture. The Trustee may require
indemnity satisfactory to it before it enforces the Indenture or the Notes. Subject to certain limitations, Holders of a majority in aggregate principal amount of the Notes then outstanding may direct
the Trustee in its exercise of any trust or power. The Trustee may withhold from Holders notice of any continuing default (except a default in payment of principal or interest) if it determines that
withholding notice is in their interests. The Company is required to file periodic reports with the Trustee as to the absence of default.

18. TRUSTEE DEALINGS WITH THE COMPANY

State
Street Bank and Trust Company of California, N.A., the Trustee under the Indenture, in its individual or any other capacity, may make loans to, accept deposits from and perform
services for the Company or an Affiliate of the Company, and may otherwise deal with the Company or an Affiliate of the Company, as if it were not the Trustee.

19. NO RECOURSE AGAINST OTHERS

A
director, officer, employee or shareholder, as such, of the Company shall not have any liability for any obligations of the Company under the Notes or the Indenture nor for any claim
based on, in respect of or by reason of such obligations or their creation. The Holder of this Note by accepting this Note waives and releases all such liability. The waiver and release are part of
the consideration for the issuance of this Note.

20. AUTHENTICATION

This
Note shall not be valid until the Trustee or an authenticating agent manually signs the certificate of authentication on the other side of this Note.

21. ABBREVIATIONS AND DEFINITIONS

Customary
abbreviations may be used in the name of the Holder 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 UGMA (= Uniform Gifts to Minors Act).

All
terms defined in the Indenture and used in this Note but not specifically defined herein are defined in the Indenture and are used herein as so defined.

22. INDENTURE TO CONTROL; GOVERNING LAW

In
the case of any conflict between the provisions of this Note and the Indenture, the provisions of the Indenture shall control. This Note shall be governed by, and construed in
accordance with, the laws of the State of New York.

The
Company will furnish to any Holder, upon written request and without charge, a copy of the Indenture. Requests may be made to: Abgenix, Inc., 6701 Kaiser Drive Fremont,
California 94555, Attention: Investor Relations.

B-7

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ASSIGNMENT FORM

To assign this Note, fill in the form below:

I
or we assign and transfer this Note to

|(Insert assignee's soc. sec. or tax I.D. no.)        
|-----------------------------------------------------
|                                                     
|                                                     
|                                                     
|                                                     
|(Print or type assignee's name, address and zip code)
|and irrevocably appoint                              
|                                                     

agent
to transfer this Note on the books of the Company. The agent may substitute another to act for him or her.

|                          |  |  |  | Your Signature:                                                   
|------------------------- |  |  |  | ------------------------------------------------------------------
|Date:                     |  |  |  |                                                                   
|                          |  |  |  | (Sign exactly as your name appears on the other side of this Note)
|*Signature guaranteed by: |  | 
|By:                       |  |  |  |                                                                   



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CONVERSION NOTICE

To convert this Note into Common Stock of the Company, check the box:

To
convert only part of this Note, state the principal amount to be converted (must be $1,000 or a integral multiple of $1,000):
$                        .

If
you want the stock certificate made out in another person's name, fill in the form below:

|(Insert assignee's soc. sec. or tax I.D. no.)        
|-----------------------------------------------------
|                                                     
|                                                     
|                                                     
|                                                     
|(Print or type assignee's name, address and zip code)

|                          |  |  |  | Your Signature:                                                   
|------------------------- |  |  |  | ------------------------------------------------------------------
|Date:                     |  |  |  |                                                                   
|                          |  |  |  | (Sign exactly as your name appears on the other side of this Note)
|*Signature guaranteed by: |  | 
|By:                       |  |  |  |                                                                   



B-9

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OPTION TO ELECT REPURCHASE  UPON A CHANGE OF CONTROL

To:
Abgenix, Inc.

The
undersigned registered owner of this Security hereby irrevocably acknowledges receipt of a notice from Abgenix, Inc. (the "Company") as to the occurrence of a Change in
Control with respect to the Company and requests and instructs the Company to redeem the entire principal amount of this Security, or the portion thereof (which is $1,000 or an integral multiple
thereof) below designated, in accordance with the terms of the Indenture referred to in this Security at the Change in Control Purchase Price, together with accrued interest to, but excluding, such
date, to the registered Holder hereof.

|Dated:                                                                                 |  |  |  |                                                                                                                                                                                                    
|-------------------------------------------------------------------------------------- |  |  |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|                                                                                       |  |  |  | Signature(s)                                                                                                                                                                                       
|                                                                                       |  |  |  | Signature(s) must be guaranteed by a qualified guarantor institution with membership in an approved signature guarantee program pursuant to Rule 17Ad-15 under the Securities Exchange Act of 1934.
|                                                                                       |  |  |  | Signature Guaranty                                                                                                                                                                                 
|Principal amount to be redeemed
(in an integral multiple of $1,000, if less than all):
|                                                                                       |  | 

NOTICE:
The signature to the foregoing Election must correspond to the Name as written upon the face of this Security in every particular, without alteration or any change whatsoever.

B-10

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SCHEDULE OF EXCHANGES OF NOTES3

The
following exchanges, redemptions, repurchases or conversions of a part of this global Note have been made:

|Principal Amount
of this Global Note
Following Such
Decrease Date
of Exchange (or Increase) |  | Authorized
Signatory of
Securities
Custodian |  | Amount of
Decrease in
Principal Amount
of this Global Note |  | Amount of
Increase in
Principal Amount
of this Global Note
|------------------------------------------------------------------------------------------- |  | -------------------------------------------- |  | ---------------------------------------------------------- |  | ----------------------------------------------------------
|                                                                                            |  |                                              |  |                                                            |  |                                                           

B-11

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