S-8

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As filed with the Securities and Exchange Commission on May 14 , 2002

Registration No. 333-            

SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM S-8
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

ABGENIX, INC.
(Exact Name of Registrant as Specified in its Charter)

Delaware	94-3248826
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification Number)

6701 Kaiser Drive
Fremont, California 94555
(510) 608-6500
(Address, including ZIP Code and Telephone Number, Including
Area Code, of Principal Executive Offices)

Abgenix, Inc. 1999 Nonstatutory Stock Option Plan
Abgenix, Inc. Canadian Employee Stock Purchase Plan

(Full Title of the Plan)

Raymond M. Withy, Ph.D.
Chief Executive Officer
Abgenix, Inc.
6701 Kaiser Drive
Fremont, California 94555
(510) 608-6500

(Name, Address Including Zip Code and Telephone Number Including Area Code
of Agent for Service of Process)

Copies to:

Susan L. Thorner
Vice President, General Counsel and Secretary
Abgenix, Inc.
6701 Kaiser Drive
Fremont, California 94555
(510) 608-6500

CALCULATION OF REGISTRATION FEE

Title of Securities to be Registered	Amount to be Registered(1)(2)	Proposed Maximum Offering Price Per Share(3)	Proposed Maximum Aggregate Offering Fee(3)	Amount of Registration Price(3)
Abgenix, Inc. 1999 Nonstatutory Stock Option Plan, Common Stock, par value $0.0001 per share	4,000,000 Shares	$13.22	$52,880,000	$4865
Abgenix, Inc. Canadian Employee Stock Purchase Plan, Common Stock, par value $0.0001 per share	200,000 Shares	$13.22	$2,644,000	$243

(1)

This registration statement covers, in addition to the number of shares of Common Stock stated above, options and other rights to purchase or acquire the shares of Common Stock covered by the prospectus or Plan.

(2)

Pursuant to Rule 416(a), this registration statement also covers any additional securities that may be offered or issued in connection with any stock split, stock dividend or similar transaction.

(3)

Pursuant to Rule 457(h), because the price of the shares to be issued pursuant to the Plan is not currently determinable, the maximum offering price, per share and in the aggregate, and the registration fee were calculated based upon the average of the high ($13.59) and low ($12.85) sale prices of Abgenix, Inc. Common Stock as reported on the Nasdaq National Market System on May 10, 2002 (which is a date within five business days of the date of filing of this registration statement).

The registration statement will become effective upon filing in accordance with Rule 462(a) under the Securities Act.

PART I

INFORMATION REQUIRED IN THE SECTION 10(A) PROSPECTUS

Item 1. Plan Information.

        The documents containing the information specified in Part I will be sent or given to employees as specified by Rule 428 (b)(1) of the Securities Act of 1933, as amended (the "Securities Act"). Such documents are not being filed with the Securities and Exchange Commission (the "SEC") either as part of this Registration Statement or as prospectus supplements pursuant to Rule 424 of the Securities Act. These documents and the documents incorporated by reference in this Registration Statement pursuant to Item 3 of Part II hereof, taken together, constitute a prospectus that meets the requirements of Section 10(a) of the Securities Act.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Incorporation of Documents by Reference.

        The SEC requires us to "incorporate by reference" certain of our publicly filed documents into this prospectus, which means that information included in those documents is considered part of the prospectus. Information that we file with the SEC after the effective date of this prospectus will automatically update and supersede this information. We incorporate by reference the documents listed below and future filings made with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 (the "Exchange Act"), as amended, until we terminate the effectiveness of this Registration Statement.

        The following documents filed with the SEC are hereby incorporated by reference:

(a)

Our latest annual report on Form 10-K filed pursuant to Section 13(a) or 15(d) of the Exchange Act containing audited financial statements for our fiscal year ended December 31, 2001, filed on March 29, 2002.



(b)

The description of our Common Stock contained in the Registration Statement on Form 8-A filed pursuant to Section 12 of the Exchange Act on May 5, 1998.



(c)

The description of our Preferred Share Purchase Rights contained in Amendment No. 2 to the Registration Statement on Form 8-A filed pursuant to Section 12 of the Exchange Act on May 14, 2002.

Item 5. The legality of the securities covered by this registration statement has been passed upon for Abgenix, Inc. by Susan L. Thorner, Esq., its Vice President, General Counsel and Secretary. Ms. Thorner owns options to purchase shares of Abgenix Common Stock that were granted to her under the Company's stock option plans.

Item 6. Indemnification of Directors and Officers.

        Our amended and restated certificate of incorporation limits the liability of directors to the maximum extent permitted by Delaware law. Delaware law provides that directors of a corporation will not be personally liable for monetary damages for breach of their fiduciary duties as directors, except liability for (1) any breach of their duty of loyalty to the corporation or its shareholders, (2) acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (3) unlawful payments of dividends or unlawful stock repurchases or redemptions or (4) any transaction from which the director derived an improper personal benefit. This limitation does not apply to liabilities arising under the federal securities laws and does not affect the availability of equitable remedies such as injunctive relief or rescission.

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        Our amended and restated bylaws provide that we shall indemnify our directors and executive officers and may indemnify our other officers and employees and other agents to the fullest extent permitted by law. We believe that indemnification under our amended and restated bylaws covers at least negligence and gross negligence on the part of indemnified parties. Our amended and restated bylaws also permit us to secure insurance on behalf of any officer, director, employee or other agent for any liability arising out of his or her actions in such capacity, regardless of whether the amended and restated bylaws would permit indemnification.

        We have entered into agreements to indemnify our directors and executive officers, in addition to the indemnification provided for in our amended and restated bylaws. These agreements, among other things, indemnify our directors and executive officers for certain expenses, including attorneys' fees, judgments, fines and settlement amounts incurred by any such person in any action or proceeding, including any action by us arising out of such person's services as our director or executive officer, any of our subsidiaries or any other company or enterprise to which the person provides services at our request. We believe that these provisions and agreements are necessary to attract and retain qualified persons as directors and executive officers.

Item 8. Exhibits.

        The following exhibits are filed as part of this Registration Statement:

Exhibit No.		Description
4.1		Amended and Restated Abgenix, Inc. 1999 Nonstatutory Stock Option Plan, effective as of January 14, 2002.
4.2		Abgenix, Inc. Canadian Employee Stock Purchase Plan.
4.3(1	)	Amended and Restated Preferred Shares Rights Agreement, between Abgenix, Inc. and Mellon Investor Services LLC, as Rights Agent, dated May 9, 2002.
5.1		Opinion of counsel re legality.
23.1		Consent of Ernst & Young LLP, Independent Auditors.
23.2		Consent of counsel (included in Exhibit 5.1).
24.1		Power of Attorney (included on the signature page of this Registration Statement).

(1)

Incorporated by reference to the same exhibit filed with the Company's Registration Statement on Form 8-A, filed May 14, 2002.

Item 9. Undertakings.

        The undersigned Registrant hereby undertakes:

        1.    To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:

(i)

To include any prospectus required by section 10(a)(3) of the Securities Act;



(ii)

To reflect in the prospectus any facts or events arising after the effective date of the Registration Statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the Registration Statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated

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maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective Registration Statement; and

(iii)

To include any material information with respect to the plan of distribution not previously disclosed in the Registration Statement or any material change to such information in the Registration Statement; provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if the registration statement is on Form S-3, Form S-8 or Form F-3, and the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the SEC by the Registrant pursuant to Section 13 or 15 (d) of the Securities Exchange Act of 1934 that are incorporated by reference in the Registration Statement.

        2.    That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new Registration Statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

        3.    To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

        4.    The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the Registrant's annual report pursuant to Section 13(a) or 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in the Registration Statement shall be deemed to be a new Registration Statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

        5.    Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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SIGNATURE

        Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Fremont, State of California, on May 14, 2002.

ABGENIX, INC.
By:	/s/  RAYMOND M. WITHY, PH.D. Name: Raymond M. Withy, Ph.D. Title: Chief Executive Officer

SIGNATURES AND POWER OF ATTORNEY

        The officers and directors of Abgenix, Inc. whose signatures appear below, hereby constitute and appoint Raymond M. Withy, Ph.D. and Kurt W. Leutzinger, and each of them, their true and lawful attorneys and agents, with full power of substitution, each with power to act alone, to sign and execute on behalf of the undersigned any amendment or amendments to this registration statement on Form S-8, and each of the undersigned does hereby ratify and confirm all that each of said attorney and agent, or their, his or her substitutes, shall do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities indicated on May 14, 2002.

Signature	Title	Date
/s/  R. SCOTT GREER R. Scott Greer	Chairman of the Board	May 14, 2002
/s/  RAYMOND M. WITHY, PH.D. Raymond M. Withy, Ph.D.	Chief Executive Officer and Director (Principal Executive Officer)	May 14, 2002
/s/  KURT W. LEUTZINGER Kurt W. Leutzinger	Chief Financial Officer (Principal Financial and Accounting Officer)	May 14, 2002
/s/  M. KATHLEEN BEHRENS, PH.D. M. Kathleen Behrens, Ph.D.	Director	May 14, 2002
/s/  RAJU S. KUCHERLAPATI, PH.D. Raju S. Kucherlapati, Ph.D.	Director	May 14, 2002
/s/  MARK B. LOGAN Mark B. Logan	Director	May 14, 2002
/s/  STEPHEN A. SHERWIN, M.D. Stephen A. Sherwin, M.D.	Director	May 14, 2002

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EXHIBIT INDEX

Exhibit No.		Description
4.1		Amended and Restated Abgenix, Inc. 1999 Nonstatutory Stock Option Plan, effective as of January 14, 2002.
4.2		Abgenix, Inc. Canadian Employee Stock Purchase Plan.
4.3	(1)	Amended and Restated Preferred Shares Rights Agreement, between Abgenix, Inc. and Mellon Investor Services LLC, as Rights Agent, dated May 9, 2002.
5.1		Opinion of counsel re legality.
23.1		Consent of Ernst & Young LLP, Independent Auditors.
23.2		Consent of counsel (included in Exhibit 5.1).
24.1		Power of Attorney (included on the signature page of this Registration Statement).

(1)

Incorporated by reference to the same exhibit filed with the Company's Registration Statement on Form 8-A, filed May 14, 2002.

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PART I INFORMATION REQUIRED IN THE SECTION 10(A) PROSPECTUS
PART II INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
SIGNATURE
SIGNATURES AND POWER OF ATTORNEY
EXHIBIT INDEX

EX-4.1

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Exhibit 4.1

ABGENIX, INC.

1999 NONSTATUTORY STOCK OPTION PLAN
(Amended and Restated as of January 14, 2002)

        1.    Purposes of the Plan.    The purposes of this Nonstatutory Stock Option Plan are:

• to attract and retain the best available personnel for positions of substantial responsibility,

• to provide additional incentive to Employees and Consultants, and

• to promote the success of the Company's business.

        Options granted under the Plan will be Nonstatutory Stock Options.

        2.    Definitions.    As used herein, the following definitions shall apply:

        (a)  "Administrator" means the Board or any of its Committees as shall be administering the Plan, in accordance with Section 4 of the Plan.

        (b)  "Applicable Laws" means the requirements relating to the administration of stock option plans under U.S. state corporate laws, U.S. federal and state securities laws, the Code, any stock exchange or quotation system on which the Common Stock is listed or quoted and the applicable laws of any foreign country or jurisdiction where Options are, or will be, granted under the Plan.

        (c)  "Board" means the Board of Directors of the Company.

        (d)  "Code" means the Internal Revenue Code of 1986, as amended.

        (e)  "Committee" means a committee of Directors appointed by the Board in accordance with Section 4 of the Plan.

        (f)    "Common Stock" means the Common Stock of the Company.

        (g)  "Company" means Abgenix, Inc., a Delaware corporation.

        (h)  "Consultant" means any person, including an advisor, engaged by the Company or a Parent or Subsidiary to render services to such entity.

        (i)    "Director" means a member of the Board.

        (j)    "Disability" means total and permanent disability as defined in Section 22(e)(3) of the Code.

        (k)  "Employee" means any person, including Officers, employed by the Company or any Parent or Subsidiary of the Company. A Service Provider shall not cease to be an Employee in the case of (i) any leave of absence approved by the Company or (ii) transfers between locations of the Company or between the Company, its Parent, any Subsidiary, or any successor. Neither service as a Director nor payment of a director's fee by the Company shall be sufficient to constitute "employment" by the Company.

        (l)    "Exchange Act" means the Securities Exchange Act of 1934, as amended.

        (m)  "Fair Market Value" means, as of any date, the value of Common Stock determined as follows:

        (i)    If the Common Stock is listed on any established stock exchange or a national market system, including without limitation the Nasdaq National Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market, its Fair Market Value shall be the closing sales price for such stock (or the closing bid, if no sales were reported) as quoted on such exchange or system for the last market trading day prior to the time of determination, as reported in The Wall Street Journal or such other source as the Administrator deems reliable;

        (ii)  If the Common Stock is regularly quoted by a recognized securities dealer but selling prices are not reported, the Fair Market Value of a Share of Common Stock shall be the mean between the high bid and low asked prices for the Common Stock on the last market trading day prior to the day of determination, as reported in The Wall Street Journal or such other source as the Administrator deems reliable;

        (iii)  In the absence of an established market for the Common Stock, the Fair Market Value shall be determined in good faith by the Administrator.

        (n)  "Notice of Grant" means a written or electronic notice evidencing certain terms and conditions of an individual Option grant. The Notice of Grant is part of the Option Agreement.

        (o)  "Officer" means a person who is an officer of the Company within the meaning of Section 16 of the Exchange Act and the rules and regulations promulgated thereunder.

        (p)  "Option" means a nonstatutory stock option granted pursuant to the Plan, that is not intended to qualify as an incentive stock option within the meaning of Section 422 of the Code and the regulations promulgated thereunder.

        (q)  "Option Agreement" means an agreement between the Company and an Optionee evidencing the terms and conditions of an individual Option grant. The Option Agreement is subject to the terms and conditions of the Plan.

        (r)  "Option Exchange Program" means a program whereby outstanding options are surrendered in exchange for options with a lower exercise price.

        (s)  "Optioned Stock" means the Common Stock subject to an Option.

        (t)    "Optionee" means the holder of an outstanding Option granted under the Plan.

        (u)  "Parent" means a "parent corporation," whether now or hereafter existing, as defined in Section 424(e) of the Code.

        (v)  "Plan" means this 1999 Nonstatutory Stock Option Plan, as Amended and Restated as of January 14, 2002.

        (w)  "Service Provider" means an Employee including an Officer or Consultant who is not also a Director.

        (x)  "Share" means a share of the Common Stock, as adjusted in accordance with Section 12 of the Plan.

        (y)  "Subsidiary" means a "subsidiary corporation," whether now or hereafter existing, as defined in Section 424(f) of the Code.

        3.    Stock Subject to the Plan.    Subject to the provisions of Section 12 of the Plan, the maximum aggregate number of Shares which may be optioned and sold under the Plan is 12,600,000 Shares. The Shares may be authorized, but unissued, or reacquired Common Stock.

        If an Option expires or becomes unexercisable without having been exercised in full, or is surrendered pursuant to an Option Exchange Program, the unpurchased Shares which were subject thereto shall become available for future grant or sale under the Plan (unless the Plan has terminated).

        4.    Administration of the Plan.

        (a)  Administration. The Plan shall be administered by (i) the Board or (ii) a Committee, which committee shall be constituted to satisfy Applicable Laws.

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        (b)  Powers of the Administrator. Subject to the provisions of the Plan, and in the case of a Committee, subject to the specific duties delegated by the Board to such Committee, the Administrator shall have the authority, in its discretion:

        (i)    to determine the Fair Market Value of the Common Stock;

        (ii)  to select the Service Providers to whom Options may be granted hereunder;

        (iii)  to determine whether and to what extent Options are granted hereunder;

        (iv)  to determine the number of shares of Common Stock to be covered by each Option granted hereunder;

        (v)  to approve forms of agreement for use under the Plan;

        (vi)  to determine the terms and conditions, not inconsistent with the terms of the Plan, of any award granted hereunder. Such terms and conditions include, but are not limited to, the exercise price, the time or times when Options may be exercised (which may be based on performance criteria), any vesting acceleration or waiver of forfeiture restrictions, and any restriction or limitation regarding any Option or the shares of Common Stock relating thereto, based in each case on such factors as the Administrator, in its sole discretion, shall determine;

        (vii) [reserved];

        (viii)  to institute an Option Exchange Program;

        (ix)  to construe and interpret the terms of the Plan and awards granted pursuant to the Plan;

        (x)  to prescribe, amend and rescind rules and regulations relating to the Plan, including rules and regulations relating to sub-plans established for the purpose of qualifying for preferred tax treatment under foreign tax laws;

        (xi)  to modify or amend each Option (subject to Section 14(b) of the Plan), including the discretionary authority to extend the post-termination exercisability period of Options longer than is otherwise provided for in the Plan, provided however, the Board shall not have the power to reprice Options or Stock Purchase Rights once granted, except for adjustments resulting from a stock split, reverse stock split or similar change to the outstanding capital stock;

        (xii) to authorize any person to execute on behalf of the Company any instrument required to effect the grant of an Option previously granted by the Administrator;

        (xiii)  to determine the terms and restrictions applicable to Options;

        (xiv) to allow Optionees to satisfy withholding tax obligations by electing to have the Company withhold from the Shares to be issued upon exercise of an Option that number of Shares having a Fair Market Value equal to the amount required to be withheld. The Fair Market Value of the Shares to be withheld shall be determined on the date that the amount of tax to be withheld is to be determined. All elections by an Optionee to have Shares withheld for this purpose shall be made in such form and under such conditions as the Administrator may deem necessary or advisable; and

        (xv) to make all other determinations deemed necessary or advisable for administering the Plan.

        (c)  Effect of Administrator's Decision. The Administrator's decisions, determinations and interpretations shall be final and binding on all Optionees and any other holders of Options.

        5.    Eligibility.    Options may be granted to Service Providers other than Officers (except as set forth in this Section 5 below). Officers and Directors shall not be eligible to receive Options under this

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Plan; provided, however, that notwithstanding anything to the contrary contained in the Plan, Options may be granted to an Officer not previously employed by the Company, as an inducement essential to the individual's entering into an employment contract with the Company.

        6.    Limitation.    Neither the Plan nor any Option shall confer upon an Optionee any right with respect to continuing the Optionee's relationship as a Service Provider with the Company, nor shall they interfere in any way with the Optionee's right or the Company's right to terminate such relationship at any time, with or without cause.

        7.    Term of Plan.    The Plan shall become effective upon its adoption by the Board. It shall continue in effect for ten (10) years, unless sooner terminated under Section 14 of the Plan.

        8.    Term of Option.    The term of each Option shall be stated in the Option Agreement.

        9.    Option Exercise Price and Consideration.

        (a)  Exercise Price. The per share exercise price for the Shares to be issued pursuant to exercise of an Option shall be determined by the Administrator.

        (b)  Waiting Period and Exercise Dates. At the time an Option is granted, the Administrator shall fix the period within which the Option may be exercised and shall determine any conditions which must be satisfied before the Option may be exercised.

        (c)  Form of Consideration. The Administrator shall determine the acceptable form of consideration for exercising an Option, including the method of payment. Such consideration may consist entirely of:

        (i)    cash;

        (ii)  check;

        (iii)  promissory note;

        (iv)  other Shares which (A) in the case of Shares acquired upon exercise of an option, have been owned by the Optionee for more than six months on the date of surrender, and (B) have a Fair Market Value on the date of surrender equal to the aggregate exercise price of the Shares as to which said Option shall be exercised;

        (v)  consideration received by the Company under a cashless exercise program implemented by the Company in connection with the Plan;

        (vi)  a reduction in the amount of any Company liability to the Optionee, including any liability attributable to the Optionee's participation in any Company-sponsored deferred compensation program or arrangement;

        (vii) such other consideration and method of payment for the issuance of Shares to the extent permitted by Applicable Laws; or

        (viii)  any combination of the foregoing methods of payment.

        10.    Exercise of Option.

        (a)  Procedure for Exercise; Rights as a Shareholder. Any Option granted hereunder shall be exercisable according to the terms of the Plan and at such times and under such conditions as determined by the Administrator and set forth in the Option Agreement. An Option may not be exercised for a fraction of a Share.

        An Option shall be deemed exercised when the Company receives: (i) written or electronic notice of exercise (in accordance with the Option Agreement) from the person entitled to exercise the Option, and (ii) full payment for the Shares with respect to which the Option is exercised. Full payment may

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consist of any consideration and method of payment authorized by the Administrator and permitted by the Option Agreement and the Plan. Shares issued upon exercise of an Option shall be issued in the name of the Optionee or, if requested by the Optionee, in the name of the Optionee and his or her spouse. Until the Shares are issued (as evidenced by the appropriate entry on the books of the Company or of a duly authorized transfer agent of the Company), no right to vote or receive dividends or any other rights as a shareholder shall exist with respect to the Optioned Stock, notwithstanding the exercise of the Option. The Company shall issue (or cause to be issued) such Shares promptly after the Option is exercised. No adjustment will be made for a dividend or other right for which the record date is prior to the date the Shares are issued, except as provided in Section 12 of the Plan.

        Exercising an Option in any manner shall decrease the number of Shares thereafter available, both for purposes of the Plan and for sale under the Option, by the number of Shares as to which the Option is exercised.

        (b)  Termination of Relationship as a Service Provider. If an Optionee ceases to be a Service Provider, other than upon the Optionee's death or Disability, the Optionee may exercise his or her Option, but only within such period of time as is specified in the Option Agreement, and only to the extent that the Option is vested on the date of termination (but in no event later than the expiration of the term of such Option as set forth in the Option Agreement). In the absence of a specified time in the Option Agreement, the Option shall remain exercisable for three (3) months following the Optionee's termination. If, on the date of termination, the Optionee is not vested as to his or her entire Option, the Shares covered by the unvested portion of the Option shall revert to the Plan. If, after termination, the Optionee does not exercise his or her Option within the time specified by the Administrator, the Option shall terminate, and the Shares covered by such Option shall revert to the Plan.

        (c)  Disability of Optionee. If an Optionee ceases to be a Service Provider as a result of the Optionee's Disability, the Optionee may exercise his or her Option within such period of time as is specified in the Option Agreement, to the extent the Option is vested on the date of termination (but in no event later than the expiration of the term of such Option as set forth in the Option Agreement). In the absence of a specified time in the Option Agreement, the Option shall remain exercisable for twelve (12) months following the Optionee's termination. If, on the date of termination, the Optionee is not vested as to his or her entire Option, the Shares covered by the unvested portion of the Option shall revert to the Plan. If, after termination, the Optionee does not exercise his or her Option within the time specified herein, the Option shall terminate, and the Shares covered by such Option shall revert to the Plan.

        (d)  Death of Optionee. If an Optionee dies while a Service Provider, the Option may be exercised within such period of time as is specified in the Option Agreement (but in no event later than the expiration of the term of such Option as set forth in the Notice of Grant), by the Optionee's estate or by a person who acquires the right to exercise the Option by bequest or inheritance, but only to the extent that the Option is vested on the date of death. In the absence of a specified time in the Option Agreement, the Option shall remain exercisable for twelve (12) months following the Optionee's termination. If, at the time of death, the Optionee is not vested as to his or her entire Option, the Shares covered by the unvested portion of the Option shall immediately revert to the Plan. The Option may be exercised by the executor or administrator of the Optionee's estate or, if none, by the person(s) entitled to exercise the Option under the Optionee's will or the laws of descent or distribution. If the Option is not so exercised within the time specified herein, the Option shall terminate, and the Shares covered by such Option shall revert to the Plan.

        (e)  Buyout Provisions. The Administrator may at any time offer to buy out for a payment in cash or Shares, an Option previously granted based on such terms and conditions as the Administrator shall establish and communicate to the Optionee at the time that such offer is made.

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        11.    Non-Transferability of Options.    Unless determined otherwise by the Administrator, an Option may not be sold, pledged, assigned, hypothecated, transferred, or disposed of in any manner other than by will or by the laws of descent or distribution and may be exercised, during the lifetime of the Optionee, only by the Optionee. If the Administrator makes an Option transferable, such Option shall contain such additional terms and conditions as the Administrator deems appropriate.

        12.    Adjustments Upon Changes in Capitalization, Dissolution, Merger or Asset Sale.

        (a)  Changes in Capitalization. Subject to any required action by the shareholders of the Company, the number of shares of Common Stock covered by each outstanding Option, and the number of shares of Common Stock which have been authorized for issuance under the Plan but as to which no Options have yet been granted or which have been returned to the Plan upon cancellation or expiration of an Option, as well as the price per share of Common Stock covered by each such outstanding Option, shall be proportionately adjusted for any increase or decrease in the number of issued shares of Common Stock resulting from a stock split, reverse stock split, stock dividend, combination or reclassification of the Common Stock, or any other increase or decrease in the number of issued shares of Common Stock effected without receipt of consideration by the Company; provided, however, that conversion of any convertible securities of the Company shall not be deemed to have been "effected without receipt of consideration." Such adjustment shall be made by the Board, whose determination in that respect shall be final, binding and conclusive. Except as expressly provided herein, no issuance by the Company of shares of stock of any class, or securities convertible into shares of stock of any class, shall affect, and no adjustment by reason thereof shall be made with respect to, the number or price of shares of Common Stock subject to an Option.

        (b)  Dissolution or Liquidation. In the event of the proposed dissolution or liquidation of the Company, the Administrator shall notify each Optionee as soon as practicable prior to the effective date of such proposed transaction. The Administrator in its discretion may provide for an Optionee to have the right to exercise his or her Option until ten (10) days prior to such transaction as to all of the Optioned Stock covered thereby, including Shares as to which the Option would not otherwise be exercisable. In addition, the Administrator may provide that any Company repurchase option applicable to any Shares purchased upon exercise of an Option shall lapse as to all such Shares, provided the proposed dissolution or liquidation takes place at the time and in the manner contemplated. To the extent it has not been previously exercised, an Option will terminate immediately prior to the consummation of such proposed action.

        (c)  Merger or Asset Sale. In the event of a merger of the Company with or into another corporation, or the sale of substantially all of the assets of the Company, each outstanding Option shall be assumed or an equivalent option or right substituted by the successor corporation or a Parent or Subsidiary of the successor corporation. In the event that the successor corporation refuses to assume or substitute for the Option, the Optionee shall fully vest in and have the right to exercise the Option as to all of the Optioned Stock, including Shares as to which it would not otherwise be vested or exercisable. If an Option becomes fully vested and exercisable in lieu of assumption or substitution in the event of a merger or sale of assets, the Administrator shall notify the Optionee in writing or electronically that the Option shall be fully vested and exercisable for a period of fifteen (15) days from the date of such notice, and the Option shall terminate upon the expiration of such period. For the purposes of this paragraph, the Option shall be considered assumed if, following the merger or sale of assets, the option or right confers the right to purchase or receive, for each Share of Optioned Stock, immediately prior to the merger or sale of assets, the consideration (whether stock, cash, or other securities or property) received in the merger or sale of assets by holders of Common Stock for each Share held on the effective date of the transaction (and if holders were offered a choice of consideration, the type of consideration chosen by the holders of a majority of the outstanding Shares); provided, however, that if such consideration received in the merger or sale of assets is not solely common stock of the successor corporation or its Parent, the Administrator may, with the consent of

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the successor corporation, provide for the consideration to be received upon the exercise of the Option, for each Share of Optioned Stock to be solely common stock of the successor corporation or its Parent equal in fair market value to the per share consideration received by holders of Common Stock in the merger or sale of assets.

        13.    Date of Grant.    The date of grant of an Option shall be, for all purposes, the date on which the Administrator makes the determination granting such Option, or such other later date as is determined by the Administrator. Notice of the determination shall be provided to each Optionee within a reasonable time after the date of such grant.

        14.    Amendment and Termination of the Plan.

        (a)  Amendment and Termination. The Board may at any time amend, alter, suspend or terminate the Plan.

        (b)  Effect of Amendment or Termination. No amendment, alteration, suspension or termination of the Plan shall impair the rights of any Optionee, unless mutually agreed otherwise between the Optionee and the Administrator, which agreement must be in writing and signed by the Optionee and the Company. Termination of the Plan shall not affect the Administrator's ability to exercise the powers granted to it hereunder with respect to options granted under the Plan prior to the date of such termination.

        15.    Conditions Upon Issuance of Shares.

        (a)  Legal Compliance. Shares shall not be issued pursuant to the exercise of an Option unless the exercise of such Option and the issuance and delivery of such Shares shall comply with Applicable Laws and shall be further subject to the approval of counsel for the Company with respect to such compliance.

        (b)  Investment Representations. As a condition to the exercise of an Option the Company may require the person exercising such Option to represent and warrant at the time of any such exercise that the Shares are being purchased only for investment and without any present intention to sell or distribute such Shares if, in the opinion of counsel for the Company, such a representation is required.

        16.    Inability to Obtain Authority.    The inability of the Company to obtain authority from any regulatory body having jurisdiction, which authority is deemed by the Company's counsel to be necessary to the lawful issuance and sale of any Shares hereunder, shall relieve the Company of any liability in respect of the failure to issue or sell such Shares as to which such requisite authority shall not have been obtained.

        17.    Reservation of Shares.    The Company, during the term of this Plan, will at all times reserve and keep available such number of Shares as shall be sufficient to satisfy the requirements of the Plan.

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ABGENIX, INC.

1999 NONSTATUTORY STOCK OPTION PLAN
(Amended and Restated as of January 14, 2002)

STOCK OPTION AGREEMENT

        Unless otherwise defined herein, the terms defined in the Plan shall have the same defined meanings in this Option Agreement.

I.    NOTICE OF STOCK OPTION GRANT

[Optionee's Name and Address]

        You have been granted an option to purchase Common Stock of the Company, subject to the terms and conditions of the Plan and this Option Agreement, as follows:

Date of Grant
Vesting Commencement Date
Exercise Price per Share	$
Total Number of Shares Granted
Total Exercise Price	$
Type of Option:	Nonstatutory Stock Option
Term/Expiration Date:

Vesting Schedule:

        Subject to the Optionee continuing to be a Service Provider on such dates, this Option shall vest and become exercisable in accordance with the following schedule:

[25% of the Shares subject to the Option shall vest twelve months after the Vesting Commencement Date, and 1/48th of the Shares subject to the Option shall vest upon the last day of each month thereafter.]

Termination Period:

        This Option may be exercised for three months after Optionee ceases to be a Service Provider. Upon the death or Disability of the Optionee, this Option may be exercised for such longer period as provided in the Plan. In no event shall this Option be exercised later than the Term/Expiration Date as provided above.

II.    AGREEMENT

        1.    Grant of Option.    The Plan Administrator of the Company hereby grants to the Optionee named in the Notice of Grant attached as Part I of this Agreement (the "Optionee") an option (the "Option") to purchase the number of Shares, as set forth in the Notice of Grant, at the exercise price per share set forth in the Notice of Grant (the "Exercise Price"), subject to the terms and conditions of the Plan, which is incorporated herein by reference. Subject to Section 14(b) of the Plan, in the event of a conflict between the terms and conditions of the Plan and the terms and conditions of this Option Agreement, the terms and conditions of the Plan shall prevail.

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        2.    Exercise of Option.

        (a)  Right to Exercise. This Option is exercisable during its term in accordance with the Vesting Schedule set out in the Notice of Grant and the applicable provisions of the Plan and this Option Agreement.

        (b)  Method of Exercise. This Option is exercisable by delivery of an exercise notice, in the form attached as Exhibit A (the "Exercise Notice"), which shall state the election to exercise the Option, the number of Shares in respect of which the Option is being exercised (the "Exercised Shares"), and such other representations and agreements as may be required by the Company pursuant to the provisions of the Plan. The Exercise Notice shall be completed by the Optionee and delivered to Chief Financial Officer of the Company. The Exercise Notice shall be accompanied by payment of the aggregate Exercise Price as to all Exercised Shares. This Option shall be deemed to be exercised upon receipt by the Company of such fully executed Exercise Notice accompanied by such aggregate Exercise Price.

        No Shares shall be issued pursuant to the exercise of this Option unless such issuance and exercise complies with Applicable Laws. Assuming such compliance, for income tax purposes the Exercised Shares shall be considered transferred to the Optionee on the date the Option is exercised with respect to such Exercised Shares.

        3.    Method of Payment. Payment of the aggregate Exercise Price shall be by any of the following, or a combination thereof, at the election of the Optionee:

        (a)  cash;

        (b)  check;

        (c)  consideration received by the Company under a cashless exercise program implemented by the Company in connection with the Plan; or

        (d)  surrender of other Shares which (i) in the case of Shares acquired upon exercise of an option, have been owned by the Optionee for more than six (6) months on the date of surrender, and (ii) have a Fair Market Value on the date of surrender equal to the aggregate Exercise Price of the Exercised Shares.

        4.    Non-Transferability of Option.    This Option may not be transferred in any manner otherwise than by will or by the laws of descent or distribution and may be exercised during the lifetime of Optionee only by the Optionee. The terms of the Plan and this Option Agreement shall be binding upon the executors, administrators, heirs, successors and assigns of the Optionee.

        5.    Term of Option.    This Option may be exercised only within the term set out in the Notice of Grant, and may be exercised during such term only in accordance with the Plan and the terms of this Option Agreement.

        6.    Tax Consequences.    Some of the federal tax consequences relating to this Option, as of the date of this Option, are set forth below. THIS SUMMARY IS NECESSARILY INCOMPLETE, AND THE TAX LAWS AND REGULATIONS ARE SUBJECT TO CHANGE. THE OPTIONEE SHOULD CONSULT A TAX ADVISER BEFORE EXERCISING THIS OPTION OR DISPOSING OF THE SHARES.

        (a)  Exercising the Option. The Optionee may incur regular federal income tax liability upon exercise of an NSO. The Optionee will be treated as having received compensation income (taxable at ordinary income tax rates) equal to the excess, if any, of the Fair Market Value of the Exercised Shares on the date of exercise over their aggregate Exercise Price. If the Optionee is an Employee or a former Employee, the Company will be required to withhold from his or her compensation or collect from Optionee and pay to the applicable taxing authorities an amount in cash equal to a percentage of this

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compensation income at the time of exercise, and may refuse to honor the exercise and refuse to deliver Shares if such withholding amounts are not delivered at the time of exercise.

        (b)  Disposition of Shares. If the Optionee holds NSO Shares for at least one year, any gain realized on disposition of the Shares will be treated as long-term capital gain for federal income tax purposes.

        7.    Entire Agreement; Governing Law.    The Plan is incorporated herein by reference. The Plan and this Option Agreement constitute the entire agreement of the parties with respect to the subject matter hereof and supersede in their entirety all prior undertakings and agreements of the Company and Optionee with respect to the subject matter hereof, and may not be modified adversely to the Optionee's interest except by means of a writing signed by the Company and Optionee. This agreement is governed by the internal substantive laws, but not the choice of law rules, of California.

        8.    NO GUARANTEE OF CONTINUED SERVICE.    OPTIONEE ACKNOWLEDGES AND AGREES THAT THE VESTING OF SHARES PURSUANT TO THE VESTING SCHEDULE HEREOF IS EARNED ONLY BY CONTINUING AS A SERVICE PROVIDER AT THE WILL OF THE COMPANY (AND NOT THROUGH THE ACT OF BEING HIRED, BEING GRANTED AN OPTION OR PURCHASING SHARES HEREUNDER). OPTIONEE FURTHER ACKNOWLEDGES AND AGREES THAT THIS AGREEMENT, THE TRANSACTIONS CONTEMPLATED HEREUNDER AND THE VESTING SCHEDULE SET FORTH HEREIN DO NOT CONSTITUTE AN EXPRESS OR IMPLIED PROMISE OF CONTINUED ENGAGEMENT AS A SERVICE PROVIDER FOR THE VESTING PERIOD, FOR ANY PERIOD, OR AT ALL, AND SHALL NOT INTERFERE WITH OPTIONEE'S RIGHT OR THE COMPANY'S RIGHT TO TERMINATE OPTIONEE'S RELATIONSHIP AS A SERVICE PROVIDER AT ANY TIME, WITH OR WITHOUT CAUSE.

        By your signature and the signature of the Company's representative below, you and the Company agree that this Option is granted under and governed by the terms and conditions of the Plan and this Option Agreement. Optionee has reviewed the Plan and this Option Agreement in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Option Agreement and fully understands all provisions of the Plan and Option Agreement. Optionee hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Administrator upon any questions relating to the Plan and Option Agreement. Optionee further agrees to notify the Company upon any change in the residence address indicated below.

OPTIONEE	ABGENIX, INC.
Signature	By
Print Name	Title
Residence Address

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EXHIBIT A

FORM OF

ABGENIX, INC.

1999 NONSTATUTORY STOCK OPTION PLAN
(Amended and Restated as of January 14, 2002)

EXERCISE NOTICE

Abgenix, Inc.
6701 Kaiser Drive
Fremont, CA 94555

Attention: Chief Financial Officer

        1.    Exercise of Option.    Effective as of today,                         ,            , the undersigned ("Purchaser") hereby elects to purchase                        shares (the "Shares") of the Common Stock of Abgenix, Inc. (the "Company") under and pursuant to the 1999 Nonstatutory Stock Option Plan, as Amended and Restated as of January 14, 2002 (the "Plan") and the Stock Option Agreement dated                        (the "Option Agreement"). The purchase price for the Shares shall be $            , as required by the Option Agreement.

        2.    Delivery of Payment.    Purchaser herewith delivers to the Company the full purchase price for the Shares.

        3.    Representations of Purchaser.    Purchaser acknowledges that Purchaser has received, read and understood the Plan and the Option Agreement and agrees to abide by and be bound by their terms and conditions.

        4.    Rights as Shareholder.    Until the issuance (as evidenced by the appropriate entry on the books of the Company or of a duly authorized transfer agent of the Company) of the Shares, no right to vote or receive dividends or any other rights as a shareholder shall exist with respect to the Optioned Stock, notwithstanding the exercise of the Option. The Shares so acquired shall be issued to the Optionee as soon as practicable after exercise of the Option. No adjustment will be made for a dividend or other right for which the record date is prior to the date of issuance, except as provided in Section 12 of the Plan.

        5.    Tax Consultation.    Purchaser understands that Purchaser may suffer adverse tax consequences as a result of Purchaser's purchase or disposition of the Shares. Purchaser represents that Purchaser has consulted with any tax consultants Purchaser deems advisable in connection with the purchase or disposition of the Shares and that Purchaser is not relying on the Company for any tax advice.

        6.    Entire Agreement; Governing Law.    The Plan and Option Agreement are incorporated herein by reference. This Agreement, the Plan and the Option Agreement constitute the entire agreement of the parties with respect to the subject matter hereof and supersede in their entirety all prior undertakings and agreements of the Company and Purchaser with respect to the subject matter hereof, and may not be modified adversely to the Purchaser's interest except by means of a writing signed by

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the Company and Purchaser. This agreement is governed by the internal substantive laws, but not the choice of law rules, of California.

Submitted by:	Accepted by:
PURCHASER	ABGENIX, INC.
Signature	By
Print Name	Title
	Date Received
Address:	Address: 6701 Kaiser Drive                Fremont, CA 94555

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EXHIBIT A FORM OF ABGENIX, INC. 1999 NONSTATUTORY STOCK OPTION PLAN (Amended and Restated as of January 14, 2002) EXERCISE NOTICE

EX-4.2

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Exhibit 4.2

As of May 1, 2002

ABGENIX, INC.

CANADIAN EMPLOYEE STOCK PURCHASE PLAN

The following constitute the provisions of the Canadian Employee Stock Purchase Plan of Abgenix, Inc.

1.    Purpose.    The purpose of the Plan is to provide employees of the Company's Designated Subsidiaries with an opportunity to purchase Common Stock of the Company through accumulated payroll deductions.

2.    Definitions.

(a)

"Administrator" has the meaning set out in Section 14 of this Plan.



(b)

"Board" shall mean the Board of Directors of Abgenix, Inc.



(c)

"Code" shall mean the Internal Revenue Code of 1986 of the United States of America, as amended.



(d)

"Common Stock" shall mean the Common Stock of the Company.



(e)

"Company" shall mean Abgenix, Inc.



(f)

"Compensation" shall mean all base straight time gross earnings, overtime, commissions, incentive payments, bonuses and other cash compensation.



(g)

"Designated Subsidiary" shall mean Abgenix Biopharma Inc. and any Subsidiary which has been designated by the Board from time to time in its sole discretion as eligible to participate in the Plan.



(h)

"Employee" shall mean any individual who is (1) an employee in Canada for tax purposes of a Designated Subsidiary; or (2) an individual who is an employee of a Designated Subsidiary and is not resident in Canada for tax purposes but is designated by the Administrator as an "Employee" for the purpose of this Plan; and whose customary employment with the Designated Subsidiary is at least twenty (20) hours per week and more than five (5) months in any calendar year. For purposes of the Plan, the employment relationship shall be treated as continuing intact while the individual is on sick leave or other leave of absence approved by the Designated Subsidiary. Where the period of leave exceeds 90 days and the individual's right to reemployment is not guaranteed either by statute or by contract, for the purposes of the Plan, the employment relationship shall be deemed to have terminated on the 91st day of such leave.



(i)

"Enrollment Date" shall mean the first day of each Offering Period.



(j)

"Exercise Date" shall mean the last day of each Purchase Period.



(k)

"Fair Market Value" shall mean, as of any date, the value of a share of Common Stock determined as follows:



(i)

If the Common Stock is listed on any established stock exchange or a national market system, including without limitation the Nasdaq National Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market, its Fair Market Value shall be the closing sales price for such stock (or the closing bid, if no sales were reported) as quoted on such exchange or system for the last market Trading Day on the date of such determination, as reported in The Wall Street Journal or such other source as the Administrator deems reliable; or

(ii)

If the Common Stock is regularly quoted by a recognized securities dealer but selling prices are not reported, its Fair Market Value shall be the mean of the closing bid and asked prices for the Common Stock on the date of such determination, as reported in The Wall Street Journal or such other source as the Administrator deems reliable; or



(iii)

In the absence of an established market for the Common Stock, the Fair Market Value thereof shall be such amount as is determined in good faith by the Administrator to be the fair market value of such share.




(l)

"Offering Period" shall mean the period of approximately twenty-four (24) months during which an Option granted pursuant to the Plan may be exercised, commencing on May 1 or November 1 of each year and terminating on the last day in the period ending twenty-four months later; provided, however, that the first Offering Period under the Plan shall commence on May 1, 2002 or such period with commencement date and duration as changed by the Board pursuant to Section 4 of this Plan.



(m)

"Option" has the meaning set out in Section 7 hereunder.



(n)

"Plan" shall mean this Canadian Employee Stock Purchase Plan.



(o)

"Purchase Period" shall mean a period of six (6) months within an Offering Period. The Purchase Periods for the first offering Period shall be as follows:

        May 1, 2002 through October 31, 2002

        November 1, 2002 through April 30, 2003

        May 1, 2003 through October 31, 2003

        November 1, 2003 through April 30, 2004

(p)

"Purchase Price" shall mean the Fair Market Value of a Share of Common Stock on the Enrollment Date or on the Exercise Date, whichever is lower.



(q)

"Reserves" shall mean the aggregate number of shares of Common Stock covered by each Option under the Plan which have not yet been exercised and the number of shares of Common Stock which have been authorized for issuance under the Plan but not yet placed under Option.



(r)

"Subsidiary" shall mean a corporation, domestic or foreign, of which more than 50% of the voting shares are held by the Company or a Subsidiary, whether or not such corporation now exists or is hereafter organized or acquired by the Company or a Subsidiary.



(s)

"Trading Day" shall mean a day on which U.S. stock exchanges and the Nasdaq System are open for trading.



(t)

"U.S. Dollar Equivalent" of a participant's payroll deductions accumulated on or before a certain date shall mean such participant's payroll deductions converted into U.S. dollars based on the noon buying rate in New York City for cable transfers in Canadian dollars as certified for customs purposes by the Federal Reserve Bank of New York on the third business day in New York immediately before the relevant date.

3.    Eligibility.

(a)

Any Employee who shall be employed by a Designated Subsidiary on a given Enrolment Date shall be eligible to participate in the Plan, subject to the requirements of Section 5(a); provided however that eligible Employees may not participate in more than one Offering Period at a time and may not participate in the Company's 1998 Employee Stock Purchase Plan.

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(b)

Any provisions of the Plan to the contrary notwithstanding, no Employee shall be granted an Option under the Plan (i) to the extent that, immediately after the grant, such Employee (or any other person whose stock would be attributed to such Employee pursuant to Section 424(d) of the Code) would own capital stock of the Company and/or hold outstanding Options to purchase such stock possessing five percent (5%) or more of the total combined voting power or value of all classes of the capital stock of the Company, or (ii) to the extent that his or her rights to purchase stock under all employee stock purchase plans of the Company and its subsidiaries accrues at a rate which exceeds Twenty-Five Thousand U.S. Dollars (US$25,000) worth of stock of the Company (determined at the Fair Market Value of the shares at the time such Option is granted) for each calendar year in which such Option is outstanding at any time.

4.    Offering Periods and Purchase Periods.

(a)

Offering Periods. The Plan shall be implemented by consecutive, overlapping Offering Periods with a new Offering Period commencing on May 1 and November 1 each year, or on such other date as the Board shall determine, and continuing thereafter until terminated in accordance with Section 20 hereof; provided, however, that the first Offering Period under the Plan shall commence on May 1, 2002. The Board shall have the power to change the duration of Offering Periods (including the commencement dates thereof) with respect to future offerings without approval from Employees or participants under the Plan if such change is announced at least five (5) days prior to the scheduled beginning of the first Offering Period to be affected thereafter.



(b)

Purchase Periods. Each Offering Period shall consist of four (4) consecutive Purchase Periods of approximately six (6) month's duration. The last day of each Purchase Period shall be the Exercise Date for such Purchase Period. A Purchase Period commencing on May 1 shall end on the next October 31. A Purchase Period commencing on November 1 shall end on the next April 30. Notwithstanding the foregoing, the Administrator may change the duration and/or frequency of any Purchase Period in its sole discretion, upon the commencement of any new Purchase Period, subject to all applicable federal and provincial laws.

5.    Participation.

(a)

An Employee may become a participant in the Plan by completing a subscription agreement authorizing payroll deductions in the form of Exhibit A to this Plan and filing it with the Company or the Designated Subsidiary's payroll office prior to the applicable Enrolment Date.



(b)

Payroll deductions for a participant shall commence on the first payroll following the Enrolment Date and shall end when terminated by the participant as provided in Section 10 hereof.

6.    Payroll Deductions.

(a)

At the time a participant files his or her subscription agreement, he or she shall elect in the subscription agreement to have payroll deductions made on each pay day during the Offering Period in an amount being a whole percentage not exceeding fifteen percent (15%) of the Compensation which he or she is entitled to receive on each pay day during the Offering Period.



(b)

All payroll deductions made for a participant shall be credited to his or her account under the Plan and shall be withheld in whole percentages only. A participant may not make any additional payments into such account.

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(c)

A participant may either (i) discontinue his or her participation in the Plan as provided in Section 10 hereof, or, (ii) increase or decrease (including to zero percent (0%)) the rate of his or her payroll deductions during the Offering Period without discontinuing his or her participation in the Plan by completing and filing with the Company a new subscription agreement authorizing a change in payroll deduction rate. The Administrator may, in its discretion, limit the number of participation rate changes during any Offering Period. The change in rate shall be effective with the first full payroll period following five (5) business days after the Company's receipt of the new subscription agreement unless the Company elects to process a given change in participation more quickly. A participant's subscription agreement shall remain in effect for successive Offering Periods unless changed in accordance with this section or terminated as provided in Section 10 hereof. For clarification purposes, a participant may participate in only one Offering Period at any time.



(d)

At the time the Option is exercised, in whole or in part, or at the time some or all of the Company's Common Stock issued under the Plan is disposed of, the participant must make adequate provision for the Company's and the Designated Subsidiary's federal, state, provincial or other tax withholding obligations, if any, which arise upon the exercise of the Option or the disposition of the Common Stock. At any time, the Company and / or the Designated Subsidiary may, but shall not be obligated to, withhold from the participant's compensation the amount necessary for the Company and the Designated Subsidiary to meet applicable withholding obligations, including any withholding required to make available to the Company or the Designated Subsidiary any tax deductions or benefits attributable to sale or early disposition of Common Stock by the Employee. The Company or the Designated Subsidiary may also require the participant to provide cash payment or cleared funding to the Company or the Designated Subsidiary to satisfy any or all of such withholding obligations before the Company issues any Common Stock to such participant.

7.    Grant of Option.    On the Enrolment Date of each Offering Period, each Employee participating in such Offering Period shall be granted an Option (the "Option") exercisable on each Exercise Date during such Offering Period to purchase at the applicable Purchase Price up to the maximum full number of shares of the Company's Common Stock determined by dividing such Employee's U.S. Dollar Equivalent of payroll deductions accumulated on or before such Exercise Date and retained in the Participant's account as of such Exercise Date by the applicable Purchase Price provided that in no event shall an Employee be permitted to purchase during each Purchase Period more than 10,000 shares of the Company's Common Stock (subject to any adjustment pursuant to Section 19), and provided further that such purchase shall be subject to the limitations set forth in Sections 3(b) and 13 hereof. Exercise of the Options shall occur as provided in Section 8 hereof, unless the participant has withdrawn pursuant to Section 10 hereof. The Option if not exercised shall expire on the last day of the relevant Offering Period.

8.    Exercise of Option.    Unless a participant withdraws from the Plan as provided in Section 10 hereof and subject to provisions under Section 19 hereof, his or her Option shall be deemed to be exercised automatically on each Exercise Date of an Offering Period, and the maximum number of full shares subject to such Option shall be purchased for such participant at the applicable Purchase Price with the U.S. Dollar Equivalents of accumulated payroll deductions in his or her account. No fractional shares shall be purchased; to the extent any payroll deductions accumulated in a participant's account are not sufficient to purchase a full share, such payroll deduction shall be retained in the participant's account for the next Purchase Period or Offering Period, as the case may be, subject to earlier withdrawal by the participant as provided in Section 10 hereof. During a participant's lifetime, a participant's Option to purchase shares hereunder is exercisable only by him or her for his or her benefit.

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9.    Delivery.

(a)

As promptly as practicable after each Exercise Date on which a purchase of shares occurs, the Company shall arrange delivery of a certificate (or proof of title) representing the shares purchased upon exercise of his or her Option to each participant or pursuant to the direction set out in the subscription agreement or the sale request, as applicable.



(b)

If a participant gives a sale request to the Company in a form specified from time to time by the Administrator and such other documents as deemed necessary by the Administrator on or before ten days prior to an Exercise Date indicating that the participant wishes to sell all of the Common Stock purchased by him or her pursuant to the exercise of his or her Option on such Exercise Date ("Sale Stock"), the Company shall forward, on behalf of the participant, such sale request to a broker selected by the Administrator (the "Selected Broker"), who upon receipt of such request will arrange for the sale of the Sale Stock as an open market order for and on behalf of such participant on the Exercise Date or as soon as practical thereafter and pay the proceeds of such sale to the participant, net of all brokerage and other applicable fees less any amount necessary to meet applicable withholding obligations of the Company or the Designated Subsidiary in respect of the exercise of the participant's Option and the disposition of the Sale Stock. By executing a sale request, the participant shall be deemed to have irrevocably authorized the Selected Broker to pay to the Company or the Designated Subsidiary from the sale proceeds of the Sale Stock such amount specified by the Company or the Designated Subsidiary necessary to meet the applicable withholding obligation of the Company or the Designated Subsidiary referred to above. Notwithstanding the above, each participant who gives a sale request to the Company shall be responsible for ensuring that he or she opens an account with the Selected Broker and, unless such participant has done so, no sale request will or can be processed.

10.    Withdrawal.

(a)

A participant may withdraw all but not less than all of the payroll deductions credited to his or her account and not yet used to exercise his or her Option under the Plan at any time by giving written notice to the Company in the form of Exhibit B to this Plan. All of the participant's payroll deductions credited to his or her account shall be paid to such participant promptly after receipt of notice of withdrawal and such participant's Option for the Offering Period shall be automatically terminated, and no further payroll deductions for the purchase of shares shall be made for such Offering Period. If a participant withdraws from an Offering Period, payroll deductions shall not resume at the beginning of the succeeding Offering Period unless the participant delivers to the Company a new subscription agreement.



(b)

A participant's withdrawal from an Offering Period shall not have any effect upon his or her eligibility to participate in any similar plan which may hereafter be adopted by the Company or in succeeding Offering Periods which commence after the termination of the Offering Period from which the participant withdraws.

11.    Termination of Employment.    Upon a participant's ceasing for any reason to be an Employee, he or she shall be deemed to have elected to withdraw from the Plan and the payroll deductions credited to such participant's account during the Offering Period but not yet used to exercise the Option shall be returned to such participant or, in the case of his or her death, to the person or persons entitled thereto under Section 15 hereof, and such participant's Option shall be terminated automatically. The preceding sentence notwithstanding, a participant who receives payment in lieu of notice of termination of employment shall be treated as continuing to be an Employee for the participant's customary number of hours per week of employment during the period in respect of which such payment in lieu of notice relates.

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12.    Interest.    A participant shall not be entitled to any interest on the payroll deductions of such participant under the Plan under any circumstances.

        13.    Stock.

(a)

The maximum number of shares of the Company's Common Stock which shall be made available for sale under the Plan shall be 200,000 shares, subject to adjustment upon changes in capitalization of the Company as provided in Section 19 hereof. If, on a given Exercise Date, the number of shares with respect to which Options are to be exercised by all participants on such Exercise Date exceeds the number of shares then available under the Plan, the Company shall make a pro rata allocation of the shares remaining available for purchase in as equitable a manner as shall be practicable and as it shall determine to be equitable in its sole discretion and funds not used to purchase shares on such Exercise Date shall be returned, in cash, without interest, to the participants.



(b)

The participant shall have no interest or voting right in shares covered by his or her Option until such Option has been exercised.



(c)

Shares to be delivered to a participant under the Plan shall be registered in the name of a registered dealer for the benefit of the participant or in the name of the participant pursuant to the subscription agreement executed by the participant and accepted by the Company.

14.    Administration.    The Plan shall be administered by the Board or a committee of members of the Board appointed by the Board (in either case referred to herein as the "Administrator"). The Administrator shall have full and exclusive discretionary authority to construe, interpret and apply the terms of the Plan, to determine eligibility and to adjudicate all disputed claims under the Plan. Every finding, decision and determination made by the Administrator shall, to the full extent permitted by law, be final and binding upon all parties.

        15.    Designation of Beneficiary.

(a)

A participant may file a written designation of beneficiary who is to receive any shares and cash, if any, from the participant's account under the Plan in the event of such participant's death subsequent to an Exercise Date on which the Option is exercised but prior to delivery to such participant of such shares and cash. In addition, a participant may file with the Company a written designation of a beneficiary who is to receive any cash from the participant's account under the Plan in the event of such participant's death prior to exercise of the Option. If a participant is married and the designated beneficiary is not the spouse, spousal consent shall be required for such designation to be effective.



(b)

Such designation of beneficiary may be changed by the participant at any time by written notice to the Company. In the event of the death of a participant and in the absence of a beneficiary validly designated under the Plan who is living at the time of such participant's death, the Company shall deliver such shares and/or cash to the executor or administrator of the estate of the participant, or if no such executor or administrator has been appointed (to the knowledge of the Company), the Company, in its discretion, and without liability to any person, may deliver such shares and/or cash to the spouse or to any one or more dependants or relatives of the participant, or if no spouse, dependant or relative is known to the Company, then to such other person as the Company may designate.

16.    Transferability.    Neither payroll deductions credited to a participant's account nor any rights with regard to the exercise of an Option or to receive shares under the Plan may be assigned, transferred, pledged or otherwise disposed of in any way (other than by will, the laws of descent and distribution or as provided in Section 15 hereof) by the participant. Any such attempt at assignment, transfer, pledge or other disposition shall be without effect, except that the Company may in its sole discretion treat

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such act as an election to withdraw funds from an Offering Period in accordance with Section 10 hereof.

17.    Use of Funds.    All payroll deductions received or held by the Company under the Plan may be used by the Company for any corporate purpose, and the Company shall not be obligated to segregate such payroll deductions.

18.    Reports.    Individual participation record accounts shall be maintained for each participant in the Plan. Statements of account shall be given to participating Employees at intervals determined by the Administrator but at least annually, which statements shall set forth the amounts of payroll deductions, the Purchase Price, the number of shares purchased and the remaining cash balance, if any.

19.    Adjustments Upon Changes in Capitalization, Dissolution, Liquidation, Merger or Asset Sale

(a)

Changes in Capitalization. Subject to any required action by the stockholders of the Company, the Reserves, the maximum number of shares each participant may purchase during each Purchase Period (pursuant to Section 7), as well as the price per share and the number of shares of Common Stock covered by each Option under the Plan which has not yet been exercised shall be adjusted proportionately for any increase or decrease in the number of issued shares of such Common Stock resulting from a stock split, reverse stock split, stock dividend, reorganization, recapitalization, merger, consolidation, spin-off, combination exchange of shares or other corporate exchange, reclassification of the Common Stock, any distribution to stockholders of shares other than regular cash dividends or any other increase or decrease in the number of shares of Common Stock effected without receipt of consideration by the Company; provided, however, that conversion of any convertible securities of the Company shall not be deemed to have been "effected without receipt of consideration". Such adjustment shall be made by the Board, whose determination in that respect shall be final, binding and conclusive. Except as expressly provided herein, no issuance by the Company of shares of stock of any class, or securities convertible into shares of stock of any class, shall affect, and no adjustment by reason thereof shall be made with respect to, the number or price of shares of Common Stock subject to an Option.



(b)

Dissolution or Liquidation. In the event of the proposed dissolution or liquidation of the Company, the Offering Period then in progress shall be shortened by setting a new Exercise Date (the "New Exercise Date"), and shall terminate immediately prior to the consummation of such proposed dissolution or liquidation, unless otherwise provided by the Board. The New Exercise Date shall be before the date of the Company's proposed dissolution or liquidation. The Board shall notify each participant in writing at least fifteen (15) business days prior to the New Exercise Date, that the Exercise Date for the participant's Option has been changed to the New Exercise Date and that the participant's Option shall be exercised automatically on the New Exercise Date, unless prior to such date the participant has withdrawn from the Offering Period as provided in Section 10 hereof.



(c)

In the event of a proposed sale of all or substantially all of the assets of the Company, or the merger of the Company with or into another corporation (a "Change in Control"), then, as determined by the Administrator in its sole discretion and without liability to any person (i) the Administrator may take such actions, if any, as it deems necessary or desirable with respect to any Option or Offering Period as of the date of the consummation of the Change in Control, (ii) any surviving or acquiring corporation may assume outstanding Options or substitute similar Options for those under the Plan, (iii) such Options may continue in full force and effect, or (iv) the participants' accumulated payroll deductions may be used to purchase shares immediately prior to the effective date of the Change in Control transaction and the participants' Options under the ongoing Offering Period(s) terminated.

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20.    Amendment or Termination.

(a)

The Board may at any time and for any reason terminate or amend the Plan. Except as provided in Sections 19 or 20 hereof, no such termination can affect or amend any Options previously granted, provided however that an Offering Period may be terminated by the Board of Directors on any Exercise Date if the Board determines that the termination of the Plan is in the best interests of the Company and its stockholders. Furthermore, except as provided in Sections 19 or 20 hereof, neither the Plan nor any Options granted under the Plan may be amended if such amendment, in the view of the Board, would adversely affect the rights of any participant, unless such participant consents.



(b)

Without stockholder consent and without regard to whether any participant's rights may be considered to have been "adversely affected," the Administrator shall be entitled to change the Offering Periods, limit the frequency and/or the number of changes in the amount withheld during an Offering Period, establish the exchange ratio applicable to amounts withheld in a currency other than U.S. dollars, permit payroll withholding in excess of the amount designated by a participant in order to adjust for delays or mistakes in the Company's processing of properly completed withholding elections, establish reasonable waiting and adjustment periods and/or accounting and crediting procedures to ensure that amounts applied toward the purchase of Common Stock for each participant properly correspond with amounts withheld from the participant's Compensation, and establish such other limitations or procedures as the Administrator determines in its sole discretion to be advisable and consistent with the Plan.



(c)

Notwithstanding any other provision of the Plan, if the Administrator determines, in its sole discretion, that the application of a particular provision or provisions of the Plan would result in inappropriate or unfair treatment of a participant or prospective participant, the Administrator may waive such provision or provisions as they apply to that participant or prospective participant. Such actions by the Administrator shall not constitute an amendment of the Plan and shall not establish a precedent or in any way restrict the Administrator's ability to act in similar or dissimilar situations that may arise in the future.

21.    Notices.    All notices or other communications by a participant to the Company and the Designated Subsidiary under or in connection with the Plan shall be deemed to have been duly given when received in the form specified by the Company and the Designated Subsidiary at the location, or by the person, designated by the Company and the Designated Subsidiary for the receipt thereof.

22.    Conditions Upon Issuance of Shares.    Shares shall not be issued with respect to an Option unless the exercise of such Option and the issuance and delivery of such shares pursuant thereto shall comply with all applicable provisions of law, domestic or foreign, including, without limitation, the Securities Act of 1933, as amended, the Securities Exchange Act of 1934, as amended, the rules and regulations promulgated thereunder, the requirements of any stock exchange upon which the shares may then be listed, and all applicable Canadian and provincial securities legislation, orders and policies and shall be further subject to the approval of counsel for the Company with respect to such compliance.

        As a condition to the exercise of an Option pursuant to Section 8, on or before the time of such exercise, the Company may require the participant whose options are so exercised to represent and warrant at the time of any such exercise that the shares are being purchased only for investment and without any present intention to sell or distribute such shares if, in the opinion of counsel for the Company, such a representation is required by any of the aforementioned applicable provisions of law.

23.    Term of Plan.    The Plan shall become effective upon its adoption by the Board of Directors, and shall continue in effect unless sooner terminated under Section 20 hereof.

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24.    Automatic Transfer to Low Price Offering Period.    To the extent permitted by any applicable laws, regulations, or stock exchange rules, if the Fair Market Value of the Common Stock on any Exercise Date (other than the final Exercise Date) in an Offering Period is lower than the Fair Market Value of the Common Stock on the Enrolment Date of such Offering Period, all participants remaining enrolled in the Plan on such Exercise Date of that Offering Period shall, immediately after the exercise of their Option on such Exercise Date be automatically withdrawn from participation in respect of such Offering Period and, unless the participant otherwise directs, shall be automatically re-enrolled in the immediately following Offering Period as of the first day thereof.

25.    Right to Continued Employment.    Nothing in the Plan shall be construed as creating any employment relationship between the Company and the Employee or as giving any Employee the right to be retained in the employ of the Company or any Designated Subsidiary or any right to any payment whatsoever except to the extent of the benefits provided for by the Plan. The participant acknowledges that neither of the Company nor the Designated Subsidiary shall incur any liability as a result of the termination of an Employee's participation under this Plan by reason of the dismissal of such Employee by the Company or any Designated Subsidiary.

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ABGENIX, INC. CANADIAN EMPLOYEE STOCK PURCHASE PLAN

EX-5.1

EXHIBIT 5.1

May 14, 2002

Abgenix, Inc.
7601 Dumbarton Circle
Fremont, California 94555

RE: REGISTRATION STATEMENT ON FORM S-8

Ladies and Gentlemen:

        I have examined the Registration Statement on Form S-8 to be filed by Abgenix, Inc. (the "Company") with the Securities and Exchange Commission in connection with the registration under the Securities Act of 1933, as amended, of four million two hundred thousand (4,200,000) shares of common stock of the Company (the "Shares") for issuance under the Abgenix, Inc. 1999 Nonstatutory Stock Option Plan and the Abgenix, Inc. Canadian Employee Stock Purchase Plan (together, the "Plans"). As legal counsel for the Company, I have examined the proceedings taken and am familiar with the proceedings proposed to be taken by the Company in connection with the sale and issuance of the Shares pursuant to the Plans.

        It is my opinion that, upon completion of the proceedings to be taken prior to the issuance of the Shares pursuant to the Prospectuses constituting part of the Registration Statement on Form S-8 and upon completion of the proceedings being taken to permit such transactions to be carried out in accordance with the securities laws of the various jurisdictions where required, the Shares, when issued and sold in the manner referred to in the Plans and the agreements which accompany the Plans, and in accordance with the Company's Certificate of Incorporation, will be legally and validly issued, fully paid and nonassessable.

        I consent to the use of this opinion as an exhibit to the Registration Statement and further consent to the use of my name wherever appearing in the Registration Statement, and the amendments thereto.

Very truly yours,

/s/ Susan L. Thorner

EX-23.1

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EXHIBIT 23.1

CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

        We consent to the incorporation by reference in the Registration Statement (Form S-8) pertaining to the Abgenix, Inc. 1999 Nonstatutory Stock Option Plan and the Abgenix, Inc. Canadian Employee Stock Purchase Plan of our report dated January 24, 2002, except for Note 13 as to which the date is March 11, 2002, with respect to the consolidated financial statements of Abgenix, Inc. included in its Annual Report (Form 10-K) for the year ended December 31, 2001, filed with the Securities and Exchange Commission.

/s/ ERNST & YOUNG LLP

Palo Alto, California
May 14, 2002

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CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS