AMENDED AND RESTATED STOCKHOLDER RIGHTS AGREEMENT

AMENDED AND RESTATED

STOCKHOLDER RIGHTS AGREEMENT



This Amended and Restated Stockholder Rights Agreement (the "Agreement") is made effective as of January 12, 1998 by and among Abgenix, Inc. (the "Company"), and the holders of Preferred Stock listed on Exhibit A attached hereto.





WHEREAS, the Company and certain holders of the Company's Series A Preferred Stock and Series B Preferred Stock entered into a Stockholders Rights Agreement, dated December 23, 1997 (the "Original Agreement");



WHEREAS, the Company will sell and issue Series C Preferred Stock to Pfizer, Inc. pursuant to the Series C Preferred Stock Purchase Agreement, of even date herewith; and



WHEREAS, the Company and the other parties to the Original Agreement desire to amend and restate the Original Agreement to include the Series C Preferred Stock as Registrable Securities.



Now, therefore, the parties agree as follows:



1. Registration Rights.



1.1 Definitions.



(a) The terms "register", "registered," and "registration" refer to a registration effected by preparing and filing a registration statement or similar document in compliance with the Act, and the declaration or ordering of effectiveness of such registration statement or document;



(b) The term "Registrable Securities" means (1) the Common Stock issuable or issued upon conversion of the Series A Preferred Stock, Series B Preferred Stock and Series C Preferred Stock and (2) any Common Stock of the Company issued as (or issuable upon the conversion or exercise of any warrant, right or other security which is issued as) a dividend or other distribution with respect to, or in exchange for or in replacement of, such Series A Preferred Stock, Series B Preferred Stock, Series C Preferred Stock or Common Stock, excluding in all cases, however, (i) any Registrable Securities sold by a holder of Registrable Securities in a transaction in which such holder's rights under this Section 1 are not assigned, or (ii) any Registrable Securities sold to or through a broker or dealer or underwriter in a public distribution or a public securities transaction.



(c) The number of shares of "Registrable Securities then outstanding" shall be determined by the number of shares of Common Stock outstanding and the number of shares of Common Stock issuable pursuant to then exercisable or convertible securities which are Registrable Securities.













(d) The term "Holder" means any person who is a party to this agreement owning or having the right to acquire Registrable Securities or any assignee thereof in accordance with Section 1.13 hereof; and



(e) The term "Form S-3" means such form under the Act as in effect on the date hereof or any registration form under the Act subsequently adopted by the Securities and Exchange Commission (the "SEC") which permits inclusion or incorporation of substantial information by reference to other documents filed by the Company with the SEC.



(f) The term "Act" shall mean the Securities Act of 1933, as amended.



1.2 Request for Registration.



(a) If the Company shall receive at any time, a written request from either (i) the Holders of at least 50% of the Registrable Securities then outstanding (including securities con vertible into Registrable Securities) or (ii) the Holders of at least 50% of the outstanding shares of the Series B Preferred Stock (or Common Stock issued or issuable upon conversion of the Series B Preferred Stock), that the Company file a registration statement under the Act covering the registration of Registrable Securities, with an anticipated aggregate offering price, net of underwriting discounts and commissions, which would exceed $5,000,000, then the Company shall, within ten (10) days of the receipt thereof, give written notice of such request to all Holders and shall, subject to the limitations of Section 1.2(b), use its diligent best efforts to effect as soon as practicable, and in any event within 90 days of the receipt of such request, the registration under the Act of all Registrable Securities which the Holders request to be registered within twenty (20) days of the mailing of such written notice by the Company; provided, however, that the Company shall not be obligated to take any action to effect any such registration, qualification or compliance pursuant to this Section 1.2(a):



(i) During the period starting with the date sixty (60) days prior to the Company's estimated date of filing of, and ending on the date 180 days immediately following the effec tive date of, any registration statement pertaining to securities of the Company (other than a registration of securities in a Rule 145 transaction or with respect to an employee benefit plan), provided that the Company is actively employing in good faith all reasonable efforts to cause such registration statement to become effective;



(ii) After the Company has effected two such registrations pursuant to this Section 1.2(a), and such registrations have been declared or ordered effective;



(iii) If the Company shall furnish to such Holders a certificate signed by the President of the Company stating that in the good faith judgment of the Board of Directors it would be seriously detrimental to the Company or its stockholders for a registration statement to be filed at such time, then the Company's obligation to use its best efforts to register, qualify or comply under this Section 1.2(a) shall be deferred for a period not to exceed 90 days from the date of receipt of written















request from the Holders; provided, however, that the Company may not utilize the right under this Section 1.2(a) more than once in any twelve-month period.



(b) If the Holders initiating the registration request hereunder (the "Initiating Holders") intend to distribute the Registrable Securities covered by their request by means of an under writing, they shall so advise the Company as a part of their request made pursuant to this Section 1.2 and the Company shall include such information in the written notice referred to in Section 1.2(a). In such event, the right of any Holder to include such Holder's Registrable Securities in such registration shall be conditioned upon such Holder's participation in such underwriting and the inclusion of such Holder's Registrable Securities in the underwriting (unless otherwise mutually agreed by a majority in interest of the Initiating Holders and such Holder) to the extent provided herein. All Holders proposing to distribute their securities through such underwriting shall (together with the Company as provided in Section 1.4(e)) enter into an underwriting agreement in customary form with the underwriter or underwriters selected for such underwriting by a majority in interest of the Initiating Holders. Notwith standing any other provision of this Section 1.2, if the underwriter advises the Initiating Holders in writ ing that marketing factors require a limitation of the number of shares to be underwritten, then the Initiating Holders shall so advise all Holders of Registrable Securities which would otherwise be under written pursuant hereto, and the number of shares of Registrable Securities that may be included in the underwriting shall be allocated among all Holders thereof, including the Initiating Holders, in proportion (as nearly as practicable) to the amount of Registrable Securities of the Company owned by each Holder.



1.3 Company Registration. If (but without any obligation to do so) the Company proposes to register (including for this purpose a registration effected by the Company for stockholders other than the Holders) any of its stock or other securities under the Act in connection with the public offering of such securities solely for cash (other than a registration relating solely to the sale of securities to participants in a Company stock benefit plan, or a registration on any form which does not include substantially the same information as would be required to be included in a registration statement cover ing the sale of the Registrable Securities), the Company shall, at such time, promptly give each Holder written notice of such registration. Upon the written request of each Holder given within twenty (20) days after mailing of written notice by the Company, the Company shall, subject to the provisions of Section 1.8, cause to be registered under the Act all of the Registrable Securities that each such Holder has requested to be registered.



1.4 Obligations of the Company. Whenever required under this Section 1 to effect the registration of any Registrable Securities, the Company shall, as expeditiously as reasonably possible:



(a) Prepare and file with the SEC a registration statement with respect to such Registrable Securities and use its best efforts to cause such registration statement to become effective, and, upon the request of the Holders of a majority of the Registrable Securities registered thereunder, keep such registration statement effective for up to ninety (90) days.

















(b) Prepare and file with the SEC such amendments and supplements to such registration statement and the prospectus used in connection with such registration statement as may be necessary to comply with the provisions of the Act with respect to the disposition of all securities covered by such registration statement.



(c) Furnish to the Holders such numbers of copies of a prospectus, including a preliminary prospectus and any amendment of or supplement thereto, in conformity with the require ments of the Act, and such other documents as they may reasonably request in order to facilitate the disposition of Registrable Securities owned by them.



(d) Cause such Registrable Securities to be registered pursuant to these provisions to be listed on each securities exchange on which similar securities issued by the Company are then listed.



(e) Use its best efforts to register and qualify the securities covered by such registration statement under such other securities or Blue Sky laws of such jurisdictions as shall be rea sonably requested by the Holders, provided that the Company shall not be required in connection there with or as a condition thereto to qualify to do business or to file a general consent to service of process in any such states or jurisdictions.



(f) In the event of any underwritten public offering, enter into and perform its obligations under an underwriting agreement, in usual and customary form, with the managing under writer(s) of such offering. Each Holder participating in such underwriting shall also enter into and per form its obligations under such an agreement provided that such underwriting agreement shall not pro vide for indemnification or contribution obligations on the part of the holders greater than the obligations set forth in Section 1.10(b).



(g) Notify each Holder of Registrable Securities covered by such registration statement at any time when a prospectus relating thereto is required to be delivered under the Act of the happening of any event as a result of which the prospectus included in such registration statement, as then in effect, includes an untrue statement of a material fact or omits to state a material fact required to be stated therein or necessary to make the statements therein not misleading or incomplete in the light of the circumstances then existing.



(h) Furnish, at the request of any Holder requesting registration of Registrable Securities pursuant to this Section 1, on the date that such Registrable Securities are delivered to the underwriters for sale in connection with a registration pursuant to this Section 1, if such securities are being sold through underwriters, or, if such securities are not being sold through underwriters, on the date that the registration statement with respect to such securities becomes effective an opinion, dated such date, of the counsel representing the Company for the purposes of such registration, in form and substance as is customarily given to underwriters in an underwritten public offering, addressed to the underwriters, if any, and to the Holders requesting registration of Registrable Securities.

















1.5 Furnish Information. It shall be a condition precedent to the obligations of the Company to take any action pursuant to this Section 1 with respect to the Registrable Securities of any selling Holder that such holder shall furnish to the Company such information regarding itself, the Registrable Securities held by it, and the intended method of disposition of such securities as shall be required to effect the registration of such Holder's Registrable Securities.



1.6 Expenses of Demand Registration. All expenses (other than underwriting discounts and commissions) incurred in connection with registrations, filings or qualifications pursuant to Section 1.2, including (without limitation) all registration, filing and qualification fees, printers' and accounting fees, fees and disbursements of counsel for the Company, and the reasonable fees and dis bursements (not to exceed $15,000) of one counsel for the selling Holders shall be borne by the Company; provided, however, that the Company shall not be required to pay for any expenses of any registration proceeding begun pursuant to Section 1.2 if the registration request is subsequently withdrawn at the request of the Holders of a majority of the Registrable Securities to be registered (in which case all Participating Holders shall bear such expenses), unless the Holders of a majority of the Registrable Securities agree to forfeit their right to a demand registration pursuant to Section 1.2; pro vided further, however, that if at the time of such withdrawal, the Holders have learned of a material adverse change in the condition, business, or prospects of the Company from that known to the Holders at the time of their request, then the Holders shall not be required to pay any of such expenses and shall retain their rights pursuant to Section 1.2.



1.7 Expenses of Company Registration. The Company shall bear and pay all expenses incurred in connection with any registration, filing or qualification of Registrable Securities with respect to the registrations pursuant to Section 1.3 for each Holder (which right may be assigned as provided in Section 1.13), including (without limitation) all registration, filing, and qualification fees, printers and accounting fees relating or apportionable thereto and the fees and disbursements (not to exceed $15,000) of one counsel for the selling Holders selected by them, but excluding underwriting dis counts and commissions relating to Registrable Securities.



1.8 Underwriting Requirements. In connection with any offering involving an underwriting of shares being issued by the Company, the Company shall not be required under Section 1.3 to include any of the Holders' securities in such underwriting unless they accept the terms of the underwriting as agreed upon between the Company and the underwriters selected by it, and then only in such quantity as will not, in the opinion of the underwriters, jeopardize the success of the offer ing by the Company; provided that such underwriting agreement shall not provide for indemnification or contribution obligations on the part of the Holders greater than the obligations set forth in Section 1.10(b). If the total amount of securities, including Registrable Securities, requested by stock holders to be included in such offering exceeds the amount of securities to be sold other than by the Company that the underwriters reasonably believe compatible with the success of the offering, then the Company shall be required to include in the offering only that number of such securities, including Registrable Securities, which the underwriters believe will not jeopardize the success of the offering (the securities so included to be apportioned pro rata among the selling stockholders according to the total amount of securities entitled to be included therein owned by each selling stockholder or in such other















proportions as shall mutually be agreed to by such selling stockholders) but in no event shall the amount of securities of the selling Holders included in the offering be reduced below twenty-five percent (25%) of the total amount of securities included in such offering, unless such offering is the initial public offer ing of the Company's securities in which case the selling stockholders may be excluded entirely if the underwrit ...