Document:

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                              DIGITAL IMPACT, INC.
                                 1998 STOCK PLAN
                     (AMENDED AND RESTATED OCTOBER 5, 1999;
                       AMENDED AND RESTATED MAY 23, 2000)

        1. Purposes of the Plan. The purposes of this 1998 Stock Plan are:

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

        -  provide additional incentive to Employees, Directors and Consultants,
           and

        -  To promote the success of the Company's business.

        Options granted under the Plan may be Incentive Stock Options or
Nonstatutory Stock Options, as determined by the Administrator at the time of
grant. Stock Purchase Rights may also be granted under the Plan.

        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 or Stock Purchase Rights 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 Digital Impact, 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.

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           (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 and Directors,
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.
For purposes of Incentive Stock Options, no such leave may exceed ninety days,
unless reemployment upon expiration of such leave is guaranteed by statute or
contract. If reemployment upon expiration of a leave of absence approved by the
Company is not so guaranteed, on the 181st day of such leave any Incentive Stock
Option held by the Optionee shall cease to be treated as an Incentive Stock
Option and shall be treated for tax purposes as a Nonstatutory Stock Option.
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; or

               (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) "IPO Effective Date" means the date upon which the Securities and
Exchange Commission declares the initial public offering of the Company's common
stock as effective.

           (o) "Incentive Stock Option" means an Option intended to qualify as
an incentive stock option within the meaning of Section 422 of the Code and the
regulations promulgated thereunder.

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           (p) "Nonstatutory Stock Option" means an Option not intended to
qualify as an Incentive Stock Option.

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

           (r) "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.

           (s) "Option" means a stock option granted pursuant to the Plan.

           (t) "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.

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

           (v) "Optioned Stock" means the Common Stock subject to an Option or
Stock Purchase Right.

           (w) "Optionee" means the holder of an outstanding Option or Stock
Purchase Right granted under the Plan.

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

           (y) "Plan" means this 1998 Stock Plan.

           (z) "Restricted Stock" means shares of Common Stock acquired pursuant
to a grant of Stock Purchase Rights under Section 11 of the Plan.

           (aa) "Restricted Stock Purchase Agreement" means a written agreement
between the Company and the Optionee evidencing the terms and restrictions
applying to stock purchased under a Stock Purchase Right. The Restricted Stock
Purchase Agreement is subject to the terms and conditions of the Plan and the
Notice of Grant.

           (bb) "Rule 16b-3" means Rule 16b-3 of the Exchange Act or any
successor to Rule 16b-3, as in effect when discretion is being exercised with
respect to the Plan.

           (cc) "Section 16(b)" means Section 16(b) of the Exchange Act.

           (dd) "Service Provider" means an Employee, Director or Consultant.

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           (ee) "Share" means a share of the Common Stock, as adjusted in
accordance with Section 13 of the Plan.

           (ff) "Stock Purchase Right" means the right to purchase Common Stock
pursuant to Section 11 of the Plan, as evidenced by a Notice of Grant.

           (gg) "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 13 of
the Plan, the maximum aggregate number of Shares which may be optioned and sold
under the Plan is 11,295,000 Shares, plus an annual increase to be added on
January 1 of each year, beginning in 2001, equal to the lesser of (i) 1,500,000
shares, (ii) 5% of the outstanding shares on such date or (iii) a lesser amount
determined by the Board. The Shares may be authorized, but unissued, or
reacquired Common Stock.

        If an Option or Stock Purchase Right 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); provided, however, that Shares that have actually been issued under
the Plan, whether upon exercise of an Option or Right, shall not be returned to
the Plan and shall not become available for future distribution under the Plan,
except that if Shares of Restricted Stock are repurchased by the Company at
their original purchase price, such Shares shall become available for future
grant under the Plan.

        4. Administration of the Plan.

           (a) Procedure.

               (i) Multiple Administrative Bodies. The Plan may be administered
by different Committees with respect to different groups of Service Providers.

               (ii) Section 162(m). To the extent that the Administrator
determines it to be desirable to qualify Options granted hereunder as
"performance-based compensation" within the meaning of Section 162(m) of the
Code, the Plan shall be administered by a Committee of two or more "outside
directors" within the meaning of Section 162(m) of the Code.

               (iii) Rule 16b-3. To the extent desirable to qualify transactions
hereunder as exempt under Rule 16b-3, the transactions contemplated hereunder
shall be structured to satisfy the requirements for exemption under Rule 16b-3.

               (iv) Other Administration. Other than as provided above, the Plan
shall be administered by (A) the Board or (B) 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;

               (ii) to select the Service Providers to whom Options and Stock
Purchase Rights may be granted hereunder;

               (iii) to determine the number of shares of Common Stock to be
covered by each Option and Stock Purchase Right granted hereunder;

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

               (v) to determine the terms and conditions, not inconsistent with
the terms of the Plan, of any Option or Stock Purchase Right granted hereunder.
Such terms and conditions include, but are not limited to, the exercise price,
the time or times when Options or Stock Purchase Rights 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 Stock Purchase Right or the shares of Common Stock relating thereto, based in
each case on such factors as the Administrator, in its sole discretion, shall
determine;

               (vi) to reduce the exercise price of any Option or Stock Purchase
Right to the then current Fair Market Value if the Fair Market Value of the
Common Stock covered by such Option or Stock Purchase Right shall have declined
since the date the Option or Stock Purchase Right was granted;

               (vii) to institute an Option Exchange Program;

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

               (ix) 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;

               (x) to modify or amend each Option or Stock Purchase Right
(subject to Section 15(c) 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;

               (xi) 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 or Stock Purchase Right 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

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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;

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

               (xiii) 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 or Stock Purchase Rights.

        5. Eligibility. Nonstatutory Stock Options and Stock Purchase Rights may
be granted to Service Providers. Incentive Stock Options may be granted only to
Employees.

        6. Limitations.

           (a) Each Option shall be designated in the Option Agreement as either
an Incentive Stock Option or a Nonstatutory Stock Option. However,
notwithstanding such designation, to the extent that the aggregate Fair Market
Value of the Shares with respect to which Incentive Stock Options are
exercisable for the first time by the Optionee during any calendar year (under
all plans of the Company and any Parent or Subsidiary) exceeds $100,000, such
Options shall be treated as Nonstatutory Stock Options. For purposes of this
Section 6(a), Incentive Stock Options shall be taken into account in the order
in which they were granted. The Fair Market Value of the Shares shall be
determined as of the time the Option with respect to such Shares is granted.

           (b) Neither the Plan nor any Option or Stock Purchase Right 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.

           (c) The following limitations shall apply to grants of Options:

               (i) No Service Provider shall be granted, in any fiscal year of
the Company, Options to purchase more than 1,000,000 Shares.

               (ii) In connection with his or her initial service, a Service
Provider may be granted Options to purchase up to an additional 1,000,000 Shares
which shall not count against the limit set forth in subsection (i) above.

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               (iii) The foregoing limitations shall be adjusted proportionately
in connection with any change in the Company's capitalization as described in
Section 13.

               (iv) If an Option is cancelled in the same fiscal year of the
Company in which it was granted (other than in connection with a transaction
described in Section 13), the cancelled Option will be counted against the
limits set forth in subsections (i) and (ii) above. For this purpose, if the
exercise price of an Option is reduced, the transaction will be treated as a
cancellation of the Option and the grant of a new Option.

        7. Term of Plan. Subject to Section 19 of the Plan, the amendment and
restatement of the Plan shall become effective upon the date of stockholder
approval of the Plan in October 1999; provided, however, that amendments that
would cause the Plan or Options granted hereunder to fail to comply with
applicable California "blue sky" securities laws shall not be effective until
the IPO Effective Date. It shall continue in effect for a term of ten (10) years
from the date of obtaining stockholder approval of the Plan in October 1999,
unless terminated earlier under Section 15 of the Plan.

        8. Term of Option. The term of each Option shall be stated in the Option
Agreement. In the case of an Incentive Stock Option, the term shall be ten (10)
years from the date of grant or such shorter term as may be provided in the
Option Agreement. Moreover, in the case of an Incentive Stock Option granted to
an Optionee who, at the time the Incentive Stock Option is granted, owns stock
representing more than ten percent (10%) of the total combined voting power of
all classes of stock of the Company or any Parent or Subsidiary, the term of the
Incentive Stock Option shall be five (5) years from the date of grant or such
shorter term as may be provided 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, subject to the following:

               (i) In the case of an Incentive Stock Option

                   (A) granted to an Employee who, at the time the Incentive
Stock Option is granted, owns stock representing more than ten percent (10%) of
the voting power of all classes of stock of the Company or any Parent or
Subsidiary, the per Share exercise price shall be no less than 110% of the Fair
Market Value per Share on the date of grant.

                   (B) granted to any Employee other than an Employee described
in paragraph (A) immediately above, the per Share exercise price shall be no
less than 100% of the Fair Market Value per Share on the date of grant.

              (ii) In the case of a Nonstatutory Stock Option, the per Share
exercise price shall be determined by the Administrator. In the case of a
Nonstatutory Stock Option intended

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to qualify as "performance-based compensation" within the meaning of Section
162(m) of the Code, the per Share exercise price shall be no less than 100% of
the Fair Market Value per Share on the date of grant.

               (iii) Notwithstanding the foregoing, Options may be granted with
a per Share exercise price of less than 100% of the Fair Market Value per Share
on the date of grant pursuant to a merger or other corporate transaction.

           (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. In the case of an Incentive Stock Option, the Administrator shall
determine the acceptable form of consideration at the time of grant. 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) any combination of the foregoing methods of payment; or

               (viii) such other consideration and method of payment for the
issuance of Shares to the extent permitted by Applicable Laws.

        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. Unless the Administrator

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provides otherwise, vesting of Options granted hereunder shall be tolled during
any unpaid leave of absence. 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 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 13 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 within such period of
time as is specified in the Option Agreement 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.

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            (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 (unless
otherwise provided for in the Notice of Grant). 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.

        11. Stock Purchase Rights.

            (a) Rights to Purchase. Stock Purchase Rights may be issued either
alone, in addition to, or in tandem with other awards granted under the Plan
and/or cash awards made outside of the Plan. After the Administrator determines
that it will offer Stock Purchase Rights under the Plan, it shall advise the
offeree in writing or electronically, by means of a Notice of Grant, of the
terms, conditions and restrictions related to the offer, including the number of
Shares that the offeree shall be entitled to purchase, the price to be paid, and
the time within which the offeree must accept such offer. The offer shall be
accepted by execution of a Restricted Stock Purchase Agreement in the form
determined by the Administrator.

            (b) Repurchase Option. Unless the Administrator determines
otherwise, the Restricted Stock Purchase Agreement shall grant the Company a
repurchase option exercisable upon the voluntary or involuntary termination of
the purchaser's service with the Company for any reason (including death or
Disability). The purchase price for Shares repurchased pursuant to the
Restricted Stock Purchase Agreement shall be the original price paid by the
purchaser and may be paid by cancellation of any indebtedness of the purchaser
to the Company. The repurchase option shall lapse at a rate determined by the
Administrator.

            (c) Other Provisions. The Restricted Stock Purchase Agreement shall
contain such other terms, provisions and conditions not inconsistent with the
Plan as may be determined by the Administrator in its sole discretion.

            (d) Rights as a Shareholder. Once the Stock Purchase Right is
exercised, the purchaser shall have the rights equivalent to those of a
shareholder, and shall be a shareholder when

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his or her purchase is entered upon the records of the duly authorized transfer
agent of the Company. No adjustment will be made for a dividend or other right
for which the record date is prior to the date the Stock Purchase Right is
exercised, except as provided in Section 13 of the Plan.

        12. Non-Transferability of Options and Stock Purchase Rights. Unless
determined otherwise by the Administrator, an Option or Stock Purchase Right 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 or Stock Purchase Right transferable, such Option
or Stock Purchase Right shall contain such additional terms and conditions as
the Administrator deems appropriate.

        13. 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 Stock Purchase Right, and the number of shares of
Common Stock which have been authorized for issuance under the Plan but as to
which no Options or Stock Purchase Rights have yet been granted or which have
been returned to the Plan upon cancellation or expiration of an Option or Stock
Purchase Right, as well as the price per share of Common Stock covered by each
such outstanding Option or Stock Purchase Right, 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 or Stock
Purchase Right.

            (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. To the extent it has not been previously exercised, an Option or
Stock Purchase Right shall terminate immediately prior to the consummation of
such proposed action.

            (c) Merger. In the event of a merger of the Company with or into
another corporation, or a sale of substantially all of the assets of the
Company, each outstanding Option and Stock Purchase Right shall be assumed or an
equivalent option or right substituted by the successor corporation or a Parent
or Subsidiary of the successor corporation. If, in such event, an Option or
Stock Purchase Right is not assumed or substituted for, the Option or Stock
Purchase Right shall

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terminate as of the date of the closing of the merger. For the purposes of this
paragraph, the Option or Stock Purchase Right 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 subject to the Option or
Stock Purchase Right immediately prior to the merger or sale of assets, the
consideration (whether stock, cash, or other securities or property) received in
the merger 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 the successor corporation,
provide for the consideration to be received upon the exercise of the Option or
Stock Purchase Right, for each Share of Optioned Stock subject to the Option or
Stock Purchase Right, 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.

        14. Date of Grant. The date of grant of an Option or Stock Purchase
Right shall be, for all purposes, the date on which the Administrator makes the
determination granting such Option or Stock Purchase Right, 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.

        15. Amendment and Termination of the Plan.

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

            (b) Shareholder Approval. The Company shall obtain shareholder
approval of any Plan amendment to the extent necessary and desirable to comply
with Applicable Laws.

            (c) 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.

        16. Conditions Upon Issuance of Shares.

            (a) Legal Compliance. Shares shall not be issued pursuant to the
exercise of an Option or Stock Purchase Right unless the exercise of such Option
or Stock Purchase Right 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.

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            (b) Investment Representations. As a condition to the exercise of an
Option or Stock Purchase Right, the Company may require the person exercising
such Option or Stock Purchase Right 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.

        17. 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.

        18. 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.

        19. Shareholder Approval. The Plan shall be subject to approval by the
shareholders of the Company within twelve (12) months after the date the Plan is
adopted. Such shareholder approval shall be obtained in the manner and to the
degree required under Applicable Laws.

                                      -13-
<PAGE>   14

                                CONSENT OF SPOUSE

        The undersigned spouse of Optionee has read and hereby approves the
terms and conditions of the Plan and this Option Agreement. In consideration of
the Company's granting his or her spouse the right to purchase Shares as set
forth in the Plan and this Option Agreement, the undersigned hereby agrees to be
irrevocably bound by the terms and conditions of the Plan and this Option
Agreement and further agrees that any community property interest shall be
similarly bound. The undersigned hereby appoints the undersigned's spouse as
attorney-in-fact for the undersigned with respect to any amendment or exercise
of rights under the Plan or this Option Agreement.

                                        -------------------------------------
                                        Spouse of Optionee

<PAGE>   15

                                    EXHIBIT A

                              DIGITAL IMPACT, INC.

                                 1998 STOCK PLAN

                                 EXERCISE NOTICE

Digital Impact, Inc.
177 Bovet Road, Suite 200
San Mateo, California 94402

Attention:

        1. Exercise of Option. Effective as of today, ________________, 200__,
the undersigned ("Purchaser") hereby elects to purchase ______________ shares
(the "Shares") of the Common Stock of Digital Impact, Inc. (the "Company") under
and pursuant to the 1998 Stock Plan (the "Plan") and the Stock Option Agreement
dated, 20___ (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 13 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.

<PAGE>   16
        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 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:                              DIGITAL IMPACT, INC.

-----------------------------------     ----------------------------------------
Signature                               By

-----------------------------------     ----------------------------------------
Print Name                              Its

Address:                                Address:

---------------------------------       Digital Impact, Inc.
---------------------------------       177 Bovet Road, Suite 200
                                        San Mateo, California 94402

                                        ----------------------------------------
                                        Date Received

                                       -2-<PAGE>   1
                                                                     EXHIBIT 4.3

                            STOCK PURCHASE AGREEMENT

        This STOCK PURCHASE AGREEMENT is dated as of the 11th day of August,
2000 by and between Coulter Pharmaceutical, Inc., a Delaware corporation with
its principal office at 600 Gateway Blvd., South San Francisco, CA 94080 (the
"Company"), and the several purchasers named in the attached Exhibit A
(individually, a "Purchaser" and collectively, the "Purchasers").

        WHEREAS, the Company desires to issue and sell to the Purchasers an
aggregate of up to 1,655,000 shares (the "Shares") of the authorized but
unissued shares of common stock, $.001 par value per share, of the Company (the
"Common Stock"); and

        WHEREAS, the Purchasers, severally, wish to purchase the Shares on the
terms and subject to the conditions set forth in this Agreement.

        NOW THEREFORE, in consideration of the mutual agreements,
representations, warranties and covenants herein contained, the parties hereto
agree as follows:

        1. DEFINITIONS. As used in this Agreement, the following terms shall
have the following respective meanings:

             (a) "AFFILIATE" of a party means any corporation or other business
entity controlled by, controlling or under common control with such party. For
this purpose "control" shall mean direct or indirect beneficial ownership of
fifty percent (50%) or more of the voting or income interest in such corporation
or other business entity.

             (b) "CLOSING DATE" means the date of the Closing.

             (c) "EXCHANGE ACT" means the Securities Exchange Act of 1934, as
amended, and all of the rules and regulations promulgated thereunder.

             (d) "REGISTRATION RIGHTS AGREEMENT" shall mean that certain
Registration Rights Agreement, dated as of the date hereof, among the Company
and the Purchasers.

             (e) "MAJORITY PURCHASERS" shall mean Purchasers which, at any given
time, hold greater than fifty percent (50%) of the voting power of the
outstanding Shares.

             (f) "SEC" shall mean the Securities and Exchange Commission.

             (g) "SECURITIES ACT" shall mean the Securities Act of 1933, as
amended, and all of the rules and regulations promulgated thereunder.

        2. PURCHASE AND SALE OF SHARES.

             2.1 PURCHASE AND SALE. Subject to and upon the terms and conditions
set forth in this Agreement, the Company agrees to issue and sell to each
Purchaser, and each Purchaser, severally, hereby agrees to purchase from the
Company, at the Closing, the number of shares of Common Stock set forth opposite
the name of such Purchaser under the heading "Number of Shares to be Purchased"
on Exhibit A hereto, at a purchase price of $ 21.625 per

                                       1.

<PAGE>   2

share. The total purchase price payable by each Purchaser for the number of
shares of Common Stock that such Purchaser is hereby agreeing to purchase is set
forth opposite the name of such Purchaser under the heading "Purchase Price" on
Exhibit A hereto. The aggregate purchase price payable by the Purchasers to the
Company for all of the Shares shall be $35,789,375.

             2.2 CLOSING. The closing of the transactions contemplated under
this Agreement (the "Closing") shall take place at the offices of Cooley Godward
LLP, Palo Alto, California, on August 28, 2000 or at such other location, date
and time as may be agreed upon between the Purchasers and the Company. At the
Closing, the Company shall deliver to each Purchaser a single stock certificate,
registered in the name of such Purchaser, representing the number of shares of
Common Stock purchased by such Purchaser, against payment of the purchase price
therefor by wire transfer of immediately available funds to such account or
accounts as the Company shall designate in writing.

        3. REPRESENTATIONS AND WARRANTIES OF THE COMPANY. The Company hereby
represents and warrants to each of the Purchasers as follows:

             3.1 INCORPORATION. The Company is a corporation duly organized,
validly existing and in good standing under the laws of the State of Delaware
and is qualified to do business in each jurisdiction in which the character of
its properties or the nature of its business requires such qualification, except
where the failure to so qualify would not have a material adverse effect upon
the Company. The Company has all requisite corporate power and authority to
carry on its business as now conducted.

             3.2 CAPITALIZATION. The authorized capital stock of the Company
consists of (i) 30,000,000 shares of Common Stock, of which 17,112,832 shares
are outstanding on the date hereof and (ii) 3,000,000 shares of preferred stock,
of which no shares are outstanding on the date hereof. Except as described in
the SEC Documents, there are no existing options, warrants, calls, preemptive
(or similar) rights, subscriptions or other rights, agreements, arrangements or
commitments of any character obligating the Company to issue, transfer or sell,
or cause to be issued, transferred or sold, any shares of the capital stock of
the Company or other equity interests in the Company or any securities
convertible into or exchangeable for such shares of capital stock or other
equity interests, and there are no outstanding contractual obligations of the
Company to repurchase, redeem or otherwise acquire any shares of its capital
stock or other equity interests.

             3.3 AUTHORIZATION. All corporate action on the part of the Company,
its officers, directors and stockholders necessary for the authorization,
execution, delivery and performance of this Agreement and the Registration
Rights Agreement and the consummation of the transactions contemplated herein
and therein has been taken. When executed and delivered by the Company, each of
this Agreement and the Registration Rights Agreement shall constitute the legal,
valid and binding obligation of the Company, enforceable against the Company in
accordance with its terms, except as such may be limited by bankruptcy,
insolvency, reorganization or other laws affecting creditors' rights generally
and by general equitable principles. The Company has all requisite corporate
power to enter into this Agreement and the

                                       2.
<PAGE>   3

Registration Rights Agreement and to carry out and perform its obligations under
the terms of this Agreement, and the Registration Rights Agreement.

             3.4 VALID ISSUANCE OF THE SHARES. The Shares being purchased by the
Purchasers hereunder will, upon issuance pursuant to the terms hereof, be duly
authorized and validly issued, fully paid and nonassessable.

             3.5 FINANCIAL STATEMENTS. The Company has furnished to each
Purchaser its audited Statements of Income, Stockholders' Equity and Cash Flows
for the fiscal year ended December 31, 1999, its audited Balance Sheet as of
December 31, 1999, its unaudited Statements of Income, Stockholders' Equity and
Cash Flows for the six month period ending June 30, 2000, and its unaudited
Balance Sheet as of June 30, 2000. All such financial statements are hereinafter
referred to collectively as the "Financial Statements". The Financial Statements
have been prepared in accordance with generally accepted accounting principles
applied on a consistent basis during the periods involved, and fairly present,
in all material respects, the financial position of the Company and the results
of its operations as of the date and for the periods indicated thereon, except
that the unaudited financial statements may not be in accordance with generally
accepted accounting principles because of the absence of footnotes normally
contained therein and are subject to normal year-end audit adjustments which,
individually, and in the aggregate, will not be material. Since June 30, 2000,
to the Company's knowledge, there has been no material adverse change (actual or
threatened) in the assets, liabilities (contingent or other), affairs,
operations, prospects or condition (financial or other) of the Company.

             3.6 SEC DOCUMENTS. The Company has furnished to each Purchaser, a
true and complete copy of the Company's Annual Report on Form 10-K for the year
ended December 31, 1999, the Company's Quarterly Report on Form 10-Q for the six
months ended June 30, 2000, and any other statement, report, registration
statement (other than registration statements on Form S-8) or definitive proxy
statement filed by the Company with the SEC during the period commencing June
30, 2000 and ending on the date hereof. The Company will, promptly upon the
filing thereof, also furnish to each Purchaser all statements, reports
(including, without limitation, Quarterly Reports on Form 10-Q and Current
Reports on Form 8-K), registration statements and definitive proxy statements
filed by the Company with the SEC during the period commencing on the date
hereof and ending on the Closing Date (all such materials required to be
furnished to each Purchaser pursuant to this sentence or pursuant to the next
preceding sentence of this Section 3.6 being called, collectively, the "SEC
Documents"). As of their respective filing dates, the SEC Documents complied or
will comply in all material respects with the requirements of the Exchange Act
or the Securities Act, as applicable, and none of the SEC Documents contained or
will contain any untrue statement of a material fact or omitted or will omit to
state a material fact required to be stated therein or necessary in order to
make the statements made therein, in light of the circumstances under which they
were made, not misleading, as of their respective filing dates, except to the
extent corrected by a subsequently filed SEC Document.

             3.7 CONSENTS. All consents, approvals, orders and authorizations
required on the part of the Company in connection with the execution, delivery
or performance of this

                                       3.
<PAGE>   4

Agreement and the Registration Rights Agreement and the consummation of the
transactions contemplated herein and therein have been obtained and will be
effective as of the Closing Date.

             3.8 NO CONFLICT. The execution and delivery of this Agreement and
the Registration Rights Agreement by the Company and the consummation of the
transactions contemplated hereby and thereby will not conflict with or result in
any violation of or default (with or without notice or lapse of time, or both)
under, or give rise to a right of termination, cancellation or acceleration of
any obligation or to a loss of a material benefit under (i) any provision of the
Certificate of Incorporation or By-laws of the Company or (ii) any agreement or
instrument, permit, franchise, license, judgment, order, statute, law,
ordinance, role or regulations, applicable to the Company or its respective
properties or assets.

             3.9 BROKERS OR FINDERS. Except for Pacific Growth Equities, Inc.
and Deutsche Banc Alex Brown the Company has not dealt with any broker or finder
in connection with the transactions contemplated by this Agreement, and, except
for certain fees and expenses payable by the Company to Pacific Growth Equities,
Inc., the Company has not incurred, and shall not incur, directly or indirectly,
any liability for any brokerage or finders' fees or agents commissions or any
similar charges in connection with this Agreement or any transaction
contemplated hereby.

             3.10 NASDAQ NATIONAL MARKET. The Common Stock is listed on the
Nasdaq National Market System, and there are no proceedings to revoke or suspend
such listing.

             3.11 ABSENCE OF LITIGATION. There is no action, suit or proceeding
or, to the Company's knowledge, any investigation, pending, or to the Company's
knowledge, threatened by or before any governmental body against the Company and
in which an unfavorable outcome, ruling or finding in any said matter, or for
all matters taken as a whole, might have a material adverse effect on the
Company. The foregoing includes, without limitation, any such action, suit,
proceeding or investigation that questions this Agreement or the Registration
Rights Agreement or the right of the Company to execute, deliver and perform
under same.

        4. REPRESENTATIONS AND WARRANTIES OF THE PURCHASERS. Each Purchaser
severally for itself, and not jointly with the other Purchasers, represents and
warrants to the Company as follows:

             4.1 AUTHORIZATION. All action on the part of such Purchaser and, if
applicable, its officers, directors and shareholders necessary for the
authorization, execution, delivery and performance of this Agreement and the
Registration Rights Agreement and the consummation of the transactions
contemplated herein and therein has been taken. When executed and delivered,
each of this Agreement and the Registration Rights Agreement will constitute the
legal, valid and binding obligation of such Purchaser, enforceable against such
Purchaser in accordance with its terms, except as such may be limited by
bankruptcy, insolvency, reorganization or other laws affecting creditors' rights
generally and by general equitable principles. Such Purchaser has all requisite
corporate power to enter into each of this Agreement and the Registration Rights
Agreement and to carry out and perform its obligations under the terms of this
Agreement and the Registration Rights Agreement.

                                       4.
<PAGE>   5

             4.2 PURCHASE ENTIRELY FOR OWN ACCOUNT. Such Purchaser is acquiring
the Shares being purchased by it hereunder for investment, for its own account,
and not for resale or with a view to distribution thereof in violation of the
Securities Act.

             4.3 INVESTOR STATUS; ETC. Such Purchaser certifies and represents
to the Company that at the time such Purchaser acquires any of the Shares, such
Purchaser will be an "Accredited Investor" as defined in Rule 501 of Regulation
D promulgated under the Securities Act and was not organized for the purpose of
acquiring the Shares. Such Purchaser's financial condition is such that it is
able to bear the risk of holding the Shares for an indefinite period of time and
the risk of loss of its entire investment. Such Purchaser has been afforded the
opportunity to ask questions of and receive answers from the management of the
Company concerning this investment and has sufficient knowledge and experience
in investing in companies similar to the Company in terms of the Company's stage
of development so as to be able to evaluate the risks and merits of its
investment in the Company.

             4.4 SHARES NOT REGISTERED. Such Purchaser understands that the
Shares have not been registered under the Securities Act, by reason of their
issuance by the Company in a transaction exempt from the registration
requirements of the Securities Act, and that the Shares must continue to be held
by such Purchaser unless a subsequent disposition thereof is registered under
the Securities Act or is exempt from such registration. The Purchaser
understands that the exemptions from registration afforded by Rule 144 (the
provisions of which are known to it) promulgated under the Securities Act depend
on the satisfaction of various conditions, and that, if applicable, Rule 144 may
afford the basis for sales only in limited amounts.

             4.5 NO CONFLICT. The execution and delivery of this Agreement and
the Registration Rights Agreement by such Purchaser and the consummation of the
transactions contemplated hereby and thereby will not conflict with or result in
any violation of or default by such Purchaser (with or without notice or lapse
of time, or both) under, or give rise to a right of termination, cancellation or
acceleration of any obligation or to a loss of a material benefit under (i) any
provision of the organizational documents of such Purchaser or (ii) any
agreement or instrument, permit, franchise, license, judgment, order, statute,
law, ordinance, rule or regulations, applicable to such Purchaser or its
respective properties or assets.

             4.6 BROKERS. Such Purchaser has not retained, utilized or been
represented by any broker or finder in connection with the transactions
contemplated by this Agreement.

             4.7 CONSENTS. All consents, approvals, orders and authorizations
required on the part of such Purchaser in connection with the execution,
delivery or performance of this Agreement and the consummation of the
transactions contemplated herein have been obtained and are effective as of the
Closing Date.

        5. CONDITIONS PRECEDENT.

             5.1 CONDITIONS TO THE OBLIGATION OF THE PURCHASERS TO CONSUMMATE
THE CLOSING. The obligation of each Purchaser to consummate the Closing and to
purchase and pay for the Shares being purchased by it pursuant to this Agreement
is subject to the satisfaction of the following conditions precedent:

                                       5.
<PAGE>   6

                    (a) The representations and warranties contained herein of
the Company shall be true and correct on and as of the Closing Date with the
same force and effect as though made on and as of the Closing Date (it being
understood and agreed by each Purchaser that, in the case of any representation
and warranty of the Company contained herein which is not hereinabove qualified
by application thereto of a materiality standard, such representation and
warranty need be true and correct only in all material respects in order to
satisfy as to such representation or warranty the condition precedent set forth
in the foregoing provisions of this Section 5.1 (a)).

                    (b) The Registration Rights Agreement shall have been
executed and delivered by the Company.

                    (c) The Company shall have performed all obligations and
conditions herein required to be performed by the Company on or prior to the
Closing Date.

                    (d) No proceeding challenging this Agreement or the
transactions contemplated hereby, or seeking to prohibit, alter, prevent or
materially delay the Closing, shall have been instituted before any court,
arbitrator or governmental body, agency or official and shall be pending.

                    (e) The purchase of and payment for the Shares by the
Purchasers shall not be prohibited by any law or governmental order or
regulation. All necessary consents, approvals, licenses, permits, orders and
authorizations of, or registrations, declarations and filings with, any
governmental or administrative agency or of any other person with respect to any
of the transactions contemplated hereby shall have been duly obtained or made
and shall be in full force and effect.

                    (f) All instruments and corporate proceedings in connection
with the transactions contemplated by this Agreement to be consummated at the
Closing shall be satisfactory in form and substance to such Purchaser, and such
Purchaser shall have received copies (executed or certified, as may be
appropriate) of all documents which such Purchaser may have reasonably requested
in connection with such transactions.

             5.2 CONDITIONS TO THE OBLIGATION OF THE COMPANY TO CONSUMMATE THE
CLOSING. The obligation of the Company to consummate the Closing and to issue
and sell to each of the Purchasers the Shares to be purchased by it at the
Closing is subject to the satisfaction of the following conditions precedent:

                    (a) The representations and warranties contained herein of
such Purchaser shall be true and correct on and as of the Closing Date with the
same force and effect as though made on and as of the Closing Date (it being
understood and agreed by the Company that, in the case of any representation and
warranty of each Purchaser contained herein which is not hereinabove qualified
by application thereto of a materiality standard, such representation and
warranty need be true and correct only in all material respects in order to
satisfy as to such representation or warranty the condition precedent set forth
in the foregoing provisions of this Section 5.2(a)).

                                       6.
<PAGE>   7

                    (b) The Registration Rights Agreement shall have been
executed and delivered by each Purchaser.

                    (c) The Purchasers shall have performed all obligations and
conditions herein required to be performed or observed by the Purchasers on or
prior to the Closing Date.

                    (d) No proceeding challenging this Agreement or the
transactions contemplated hereby, or seeking to prohibit, alter, prevent or
materially delay the Closing, shall have been instituted before any court,
arbitrator or governmental body, agency or official and shall be pending.

                    (e) The sale of the Shares by the Company shall not be
prohibited by any law or governmental order or regulation. All necessary
consents, approvals, licenses, permits, orders and authorizations of, or
registrations, declarations and filings with, any governmental or administrative
agency or of any other person with respect to any of the transactions
contemplated hereby shall have been duly obtained or made and shall be in full
force and effect.

                    (f) Each of the Purchasers shall have executed and delivered
to the Company a Purchaser's Questionnaire, in the form attached hereto as
Exhibit B, pursuant to which each such Purchaser shall provide information
necessary to confirm each such Purchaser's status as an "accredited investor"
(as such term is defined in Rule 501 promulgated under the Securities Act)".

                    (g) Each of the other Purchasers shall have purchased, in
accordance with this Agreement, the number of shares of Common Stock set forth
opposite its name under the heading "Number of Shares to be Purchased" on
Exhibit A.

                    (h) All instruments and corporate proceedings in connection
with the transactions contemplated by this Agreement to be consummated at the
Closing shall be satisfactory in form and substance to the Company, and the
Company shall have received counterpart originals, or certified or other copies
of all documents, including without limitation records of corporate or other
proceedings, which it may have reasonably requested in connection therewith.

        6. TRANSFER, LEGENDS.

             6.1 SECURITIES LAW TRANSFER RESTRICTIONS. No Purchaser shall sell,
assign, pledge, transfer or otherwise dispose or encumber any of the Shares
being purchased by it hereunder, except (i) pursuant to an effective
registration statement under the Securities Act or (ii) pursuant to an available
exemption from registration under the Securities Act and applicable state
securities laws and, if requested by the Company, upon delivery by such
Purchaser of an opinion of counsel reasonably satisfactory to the Company to the
effect that the proposed transfer is exempt from registration under the
Securities Act and applicable state securities laws. Any transfer or purported
transfer of the Shares in violation of this Section 6.1 shall be voidable by the
Company. The Company shall not register any transfer of the Shares in violation
of this Section 6.1. The Company may, and may instruct any transfer agent for
the Company, to place

                                       7.
<PAGE>   8

such stop transfer orders as may be required on the transfer books of the
Company in order to ensure compliance with the provisions of this Section 6.1.

             6.2 LEGENDS. Each certificate requesting any of the Shares shall be
endorsed with the legends set forth below, and each Purchaser covenants that,
except to the extent such restrictions are waived by the Company, it shall not
transfer the shares represented by any such certificate without complying with
the restrictions on transfer described in this Agreement and the legends
endorsed on such certificate:

             "THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
        REGISTERED UNDER THE SECURITIES ACT OF 1933 AND MAY NOT BE OFFERED,
        SOLD, ASSIGNED, PLEDGED TRANSFERRED OR OTHERWISE DISPOSED OF IN THE
        ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT UNDER SAID ACT OR
        PURSUANT TO AN AVAILABLE EXEMPTION FROM REGISTRATION UNDER SAID ACT AND,
        IF REQUESTED BY THE COMPANY, UPON DELIVERY OF AN OPINION OF COUNSEL
        REASONABLY SATISFACTORY TO THE COMPANY THAT THE PROPOSED TRANSFER IS
        EXEMPT FROM SAID ACT."

        7. TERMINATION; LIABILITIES CONSEQUENT THEREON. This Agreement may be
terminated and the transactions contemplated hereunder abandoned at any time
prior to the Closing only as follows:

             (a) by the Purchasers, upon notice Company if the conditions set
forth in Section 5.1 shall not have been satisfied on or prior to August 31,
2000; or

             (b) by the Company, upon notice to the Purchasers if the conditions
set forth in Section 5.2 shall not have been satisfied on or prior to August 31,
2000; or

             (c) at any time by mutual agreement of the Company and the
Purchasers; or

             (d) by the Purchasers, if there has been any breach of any
representation or warranty or any material breach of any covenant of the Company
contained herein and the same has not been cured within 15 days after notice
thereof, (it being understood and agreed by each Purchaser that, in the case of
any representation or warranty of the Company contained herein which is not
hereinabove qualified by application thereto of a materiality standard, such
representation or warranty will be deemed to have been breached for purposes of
this Section 7.1 (d) only if such representation or warranty was not true and
correct in all material respects at the time such representation or warranty was
made by the Company); or

             (e) by the Company, if there has been any breach of any
representation, warranty or any material breach of any covenant of any Purchaser
contained herein and the same has not been cured within 15 days after notice
thereof (it being understood and agreed by the Company that, in the case of any
representation and warranty of the Purchaser contained herein which is not
hereinabove qualified by application thereto of a materiality standard, such
representation or warranty will be deemed to have been breached for purposes of
this Section 7.1

                                       8.
<PAGE>   9

(e) only if such representation or warranty was not true and correct in all
material respects at the time such representation or warranty was made by such
Purchaser).

        Any termination pursuant to this Section 7 shall be without liability on
the part of any party, unless such termination is the result of a material
breach of this Agreement by a party to this Agreement in which case such
breaching party shall remain liable for such breach notwithstanding any
termination of this Agreement.

        8. MISCELLANEOUS PROVISIONS.

             8.1 FURTHER ASSURANCES. Each party agrees to cooperate fully with
the other party and to execute such further instruments, documents and
agreements and to give such further written assurances, as may be reasonably
requested by the other party to better evidence and reflect the transactions
described herein and contemplated hereby, and to carry into effect the intents
and purposes of this Agreement.

             8.2 RIGHTS CUMULATIVE. Each and all of the various rights, powers
and remedies of the parties shall be considered to be cumulative with and in
addition to any other rights, powers and remedies which such parties may have at
law or in equity in the event of the breach of any of the terms of this
Agreement. The exercise or partial exercise of any right, power or remedy shall
neither constitute the exclusive election thereof nor the waiver of any other
right, power or remedy available to such party.

             8.3 NOTICES.

                    (a) Any notices, reports or other correspondence
(hereinafter collectively referred to as "correspondence") required or permitted
to be given hereunder shall be sent by postage prepaid first class mail, courier
or telecopy or delivered by hand to the party to whom such correspondence is
required or permitted to be given hereunder. The date of giving any notice shall
be the date of its actual receipt.

                    (b) All correspondence to the Company shall be addressed as
follows:

                                       Coulter Pharmaceutical, Inc.
                                       600 Gateway Blvd.
                                       South San Francisco, CA  94080
                                       Attention:  Michael F. Bigham
                                       Title:  Chief Executive Officer
                                       Telecopier: (650) 553-2728

                             with a copy to:

                                       James C. Kitch
                                       Cooley Godward LLP
                                       5 Palo Alto Square
                                       Palo Alto, CA  94306
                                       Telecopier: (650) 849-7400

                                       9.
<PAGE>   10

                    (c) All correspondence to any Purchaser shall be sent to
such Purchaser at the address set forth in Exhibit A.

                    (d) Any entity may change the address to which
correspondence to it is to be addressed by notification as provided for herein.

             8.4 CAPTIONS. The captions and paragraph headings of this Agreement
are solely for the convenience of reference and shall not affect its
interpretation.

             8.5 SEVERABILITY. Should any part or provision of this Agreement be
held unenforceable or in conflict with the applicable laws or regulations of any
jurisdiction, the invalid or unenforceable part or provisions shall be replaced
with a provision which accomplishes, to the extent possible, the original
business purpose of such part or provision in a valid and enforceable manner,
and the remainder of this Agreement shall remain binding upon the parties
hereto.

             8.6 GOVERNING LAW; INJUNCTIVE RELIEF.

                    (a) This Agreement shall be governed by and construed in
accordance with the internal and substantive laws of California and without
regard to any conflicts of laws concepts which would apply the substantive law
of some other jurisdiction.

                    (b) Each of the parties hereto acknowledges and agrees that
damages will not be an adequate remedy for any material breach or violation of
this Agreement if such material breach or violation would cause immediate and
irreparable harm (an "Irreparable Breach"). Accordingly, in the event of a
threatened or ongoing Irreparable Breach, each party hereto shall be entitled to
seek, in any state or federal court in the State of California, equitable relief
of a kind appropriate in light of the nature of the ongoing or threatened
Irreparable Breach, which relief may include, without limitation, specific
performance or injunctive relief; provided, however, that if the party bringing
such action is unsuccessful in obtaining the relief sought, the moving party
shall pay the non-moving party's reasonable costs, including attorney's fees,
incurred in connection with defending such action. Such remedies shall not be
the parties' exclusive remedies, but shall be in addition to all other remedies
provided in this Agreement.

             8.7 WAIVER. No waiver of any term, provision or condition of this
Agreement, whether by conduct or otherwise, in any one or more instances, shall
be deemed to be, or be construed as, a further or continuing waiver of any such
term, provision or condition or as a waiver of any other term, provision or
condition of this Agreement.

             8.8 EXPENSES. Each party will bear its own costs and expenses in
connection with this Agreement.

             8.9 ASSIGNMENT. The rights and obligations of the parties hereto
shall inure to the benefit of and shall be binding upon the authorized
successors and permitted assigns of each party. Neither party may assign its
rights or obligations under this Agreement or designate another person (i) to
perform all or part of its obligations under this Agreement or (ii) to have all
or part of its rights and benefits under this Agreement, in each case without
the prior written consent of the other party. In the event of any assignment in
accordance with the terms of this

                                      10.
<PAGE>   11

Agreement, the assignee shall specifically assume and be bound by the provisions
of the Agreement by executing and agreeing to an assumption agreement reasonably
acceptable to the other party.

             8.10 SURVIVAL. The respective representations and warranties given
by the parties hereto, and the other covenants and agreements contained herein,
shall survive the Closing Date and the consummation of the transactions
contemplated herein for a period of two years, without regard to any
investigation made by any party.

             8.11 ENTIRE AGREEMENT. This Agreement constitutes the entire
agreement between the parties hereto respecting the subject matter hereof and
supersedes all prior agreements, negotiations, understandings, representations
and statements respecting the subject matter hereof, whether written or oral. No
modification, alteration, waiver or change in any of the terms of this Agreement
shall be valid or binding upon the parties hereto unless made in writing and
duly executed by the Company and the Majority Purchasers.

        The foregoing agreement is hereby executed as of the date first above
written.

                                       COMPANY:

                                       Coulter Pharmaceutical, Inc.

                                       By:
                                          ------------------------------------

IN INITIAL INVESTOR'S SIGNATURE TO THE INVESTOR QUESTIONNAIRE DATED EVEN DATE
HEREWITH SHALL CONSTITUTE THE INITIAL INVESTOR'S SIGNATURE TO THIS STOCK
PURCHASE AGREEMENT.

                                      11.
<PAGE>   12

                                    EXHIBIT A

                                   PURCHASERS

<TABLE>
<CAPTION>
                                                                                       NUMBER OF SHARES TO BE
                              PURCHASERS                                                      PURCHASED
                              ----------                                               ----------------------
<S>                                                                                    <C>
Alta Embarcadero BioPharma, LLC ...........................................                     10,824
Alta BioPharma Partners, LP. ..............................................                    287,173
Coulter Pharmaceuticals Chase Partners (Alta Bio), LLC ....................                    164,003
Marcuard Cook & Cie, SA ...................................................                     20,000
Narragansett Offshore Ltd. ................................................                     57,000
Narragansett I LP. ........................................................                     43,000
Three Arch Partners III, L.P. .............................................                    219,219
Three Arch Partners III, L.P. .............................................                     11,781
The Timken Living Trust UAD 9/14/99 .......................................                     50,000
Baker / Tisch Investments LLC .............................................                     92,400
Four Partners .............................................................                    231,000
FBB Associates ............................................................                     46,200
Baker Bros. Investments ...................................................                     92,400
Veritas SG Investment Trust GmbH ..........................................                     80,000
John Sullivan IRA .........................................................                      2,200
Herbert G. Roskind, Jr. IRA ...............................................                      2,100
Presbyterian Homes * Family Services, Inc. ................................                      2,800
International Truck & Engine Corp. - Hourly ...............................                     10,500
International Truck & Engine Corp. - Salaried .............................                     15,600
International Truck & Engine Corp.- VEBA ..................................                      8,100
The University of Mississippi .............................................                      1,100
The University of Mississippi Medical  Center .............................                      1,700
The University of Mississippi Foundation ..................................                      8,200
Michigan Botanic Garden Foundation ........................................                      2,300
Meijer Foundation .........................................................                      3,200
Frederik Meijer Charitable Trust ..........................................                      3,300
ATP Tour Inc. Player Pension Plan .........................................                      2,000
MJH Foundation ............................................................                      6,800
Commonfund Group ..........................................................                     49,000
City of Springfield .......................................................                      3,600
</TABLE>

                                       1.
<PAGE>   13

<TABLE>
<S>                                                                                           <C>
Charlottesville, VA Retirement System .....................................                      2,100
Meijer, Inc. Pension Plan .................................................                     10,300
Bridgeport Hospital Pension ...............................................                      1,700
Bridgeport Hospital Foundation ............................................                        900
Bridgewater College .......................................................                      1,700
Trustees of Boston College ................................................                      4,500
University of Virginia ....................................................                      3,800
Richard M. Drury IRA ......................................................                      1,400
Joan P. Drury IRA .........................................................                        100
James B. & Bruce R. Murray ................................................                      4,000
Ned's Island Investment Corp. .............................................                      2,700
Joseph F. & Marlene M. Bonasera ...........................................                      1,000
Frederik G.H. Meijer Trust ................................................                        900
Lena E. S. Meijer Trust ...................................................                        400
Laura C. Roskind ..........................................................                        100
Wheaton College ...........................................................                      8,200
Tremont Temple Baptist Church General Trust Fund ..........................                     10,000
Tremont Temple Bobbie Currie Sunday School Fund ...........................                      3,000
The Berkeley Retirement Home ..............................................                      3,000
Baillie Lumber Co. Inc. Profit Share Plan .................................                      3,800
Dows - First Calvary Baptist Church .......................................                      2,000
Buzz Johnson, IRA .........................................................                      1,600
Society for the Preservation of New England Antiquities ...................                      3,700
The Evangelical Covenant Church Pension Fund ..............................                      4,900
1101 Foundation ...........................................................                      3,300
General Board of Church of Nazarene .......................................                     21,000
St. Joseph Health System ..................................................                     15,500
Bryan N. Danforth #2 ......................................................                      6,000
Jeffrey S. Meyer ..........................................................                        700
Richard J. Tavilla ........................................................                      1,500
Kirk Ware .................................................................                      1,200
Dr. G. Timothy Johnson M.D., P.C., MPPP ...................................                      1,000
Republic National Bank INSIGHT Funds ......................................                      1,500
</TABLE>

                                       2.
<PAGE>   14

                                   EXHIBIT B

                             INVESTOR QUESTIONNAIRE

INSTRUCTIONS

     The purpose of this Questionnaire is to determine whether you meet the
investor suitability standards imposed by Regulation D promulgated under the
Securities Act of 1933, as amended (the "Act"), and generally to assist Coulter
Pharmaceutical, Inc. (the "Company") in complying with the requirements of the
Act and any applicable state securities laws. The securities being offered have
not been, and will not be, registered under the Act and are being sold in
reliance upon an exemption from the registration requirements of the Act and
exemptions from applicable state securities laws. The information furnished
herein will be relied upon in connection with the offering and sale of
securities in compliance with the aforesaid exemption. Please direct any
questions regarding this Questionnaire to (Quoc An Nguyen or Jane Ross) at (650)
843-5000.

     All information supplied will be treated in confidence, except that this
Investor Questionnaire may be provided to such parties as deemed appropriate or
necessary to establish the availability of an exemption from registration under
the Act and under state securities laws.

               PLEASE COMPLETE, SIGN, AND DATE THIS QUESTIONNAIRE
                       AND RETURN IT TO THE ATTENTION OF:
                                 JANE ROSS, ESQ.
                               COOLEY GODWARD LLP
                               5 PALO ALTO SQUARE
                               PALO ALTO, CA 94306

   A PREPAID FEDERAL EXPRESS ENVELOPE HAS BEEN ENCLOSED FOR YOUR CONVENIENCE.

     PLEASE ANSWER EACH QUESTION. (Please print or type.) If the answer to any
question is "None" or "Not Applicable," please so state.

Name of Investor:
                 ---------------------------------------------------------------
Citizenship:
            --------------------------------------------------------------------
Residence Address:
                  --------------------------------------------------------------
Social Security Number or
                         -------------------------------------------------------
Tax Identification Number:
                         -------------------------------------------------------
Occupation or Business:
                       ---------------------------------------------------------
Business Address:
                 ---------------------------------------------------------------

1.   Individuals please respond to the following questions by placing an "X"
     next to the appropriate answer.

                                       1.

<PAGE>   15

     (a)  Did your individual income without regard to that of your spouse
          exceed $200,000 in the last two full calendar years, and do you
          reasonably expect such individual income to exceed $200,000 in the
          current year? For the purpose of this question, income includes earned
          income, as well as other items of ordinary income, such as dividends,
          interest, and royalties, but excludes capital gains.

          Yes ____ No ____

     (b)  Did your joint income with your spouse exceed $300,000 in the last two
          full calendar years, and do you reasonably expect such joint income to
          exceed $300,000 in the current year? For the purpose of this question,
          income includes earned income, as well as other items of ordinary
          income, such as dividends, interest, and royalties, but excludes
          capital gains.

          Yes ____ No ____

     (c)  Does your net worth or joint net worth with that of your spouse exceed
          $1,000,000?

          Yes ____ No ____

     (d)  Are you a broker or dealer registered pursuant to Section 15 of the
          Securities Exchange Act of 1934?

          Yes ____ No ____

     (e)  Set forth in the space provided below the state(s), if any, in the
          United States in which you maintained your residence during the past
          two years and the dates during which you resided in each state:

          ------------------------------------------------

          ------------------------------------------------

     (f)  Are you a director or executive officer of the Company?

          Yes ____ No ____

2.   Corporations, partnerships, and investors other than individuals, please
     answer the following questions:

     (a)  Under the laws of what jurisdiction were you formed? _________________

     (b)  Were you formed for the purpose of investing in the securities being
          offered?

          Yes ____ No ____

     (c)  Are you a national bank or a banking institution organized under the
          laws of any state or any territory of the United States or the
          District of Columbia?

          Yes ____ No ____

                                       2.

<PAGE>   16

     (d)  Are you a savings and loan association, building and loan association,
          cooperative bank, homestead association, or similar institution, which
          is supervised and examined by any state or federal authority having
          supervision over such institution?

          Yes ____ No ____

     (e)  Are you a broker or dealer registered pursuant to Section 15 of the
          Securities Exchange Act of 1934?

          Yes ____ No ____

     (f)  Are you a company (i) whose primary and predominant business is
          underwriting insurance and subject to the supervision by a regulatory
          agency under the laws of any state or territory, or (ii)registered as
          an investment company under the Investment Company Act of 1940, or
          (iii) a Small Business Investment Company licensed by the U.S. Small
          Business Administration ("SBIC")?

          Yes ____ No ____

     (g)  Are you a "business development company" within the meaning of the
          Investment Company Act of 1940 or the Investment Advisers Act of 1940?

          Yes ____ No ____

     (h)  Are you an employee benefit plan under the Employee Retirement Income
          Security Act of 1974 (a "Plan") with assets in excess of $5,000,000?

          Yes ____ No ____

          If you are such a Plan, but if the Plan's total assets do not exceed
          $5,000,000, are investment decisions for the Plan made by a bank,
          savings and loan association, insurance company or registered
          investment adviser acting as fiduciary? (If yes, please specify the
          name of the fiduciary.)

          Yes ____ No ____

          Name of Fiduciary: ___________________

          If you are a self-directed Plan, but if the Plan's total assets do not
          exceed $5,000,000, are investment decisions made solely by persons or
          entities that can answer yes to one or more of the questions under
          paragraphs (b) - (e) of Item 1, or (c) - (k) under this Item 2? (If
          yes, please specify the applicable Item and Paragraph.)

          Yes ____ No ____

          Item and Paragraph: ______________

                                       3.

<PAGE>   17

     (i)  Are you (A)(i) a tax exempt organization which is qualified under
          Section 501(c)(3) of the Internal Revenue Code of 1986 as amended, or
          (ii) a corporation, or (iii) a Massachusetts or similar business
          trust, or (iv) partnership, not formed for the specific purpose of
          acquiring the securities offered, and(B) which has assets in excess of
          $5,000,000?

          Yes ____ No ____

     (j)  Are you a trust, with total assets in excess of $5,000,000, not formed
          for the specific purpose of acquiring the securities offered, whose
          purchase is directed by a person who has such knowledge and experience
          in financial and business matters that he is capable of evaluating the
          merits and risks of the prospective investment?

          Yes ____ No ____

          If yes, please attach a memorandum describing such person's
          educational background, professional memberships or licenses, current
          employment, principal business and professional activities during the
          last five years, and experience as an investor in securities. Include
          any additional information evidencing that such person has sufficient
          knowledge and experience in financial matters that such person would
          be capable of evaluating the merits and risks of investing in the
          securities being offered.

     (k)  Are you an entity in which all of the equity owners are persons who
          are either (i) entities described in paragraphs (c) through (j) above;
          (ii) individuals whose net worth, or joint net worth with their
          spouses, exceeds $1,000,000; (iii)individuals whose income without
          regard to that of their spouses exceeded $200,000, or whose joint
          income with their spouses exceeded $300,000, in each of the last two
          years and who reasonably expect such individual income to exceed
          $200,000 or such joint income to exceed $300,000 this year; or (iv)
          individuals who are brokers or dealers registered pursuant to Section
          15 of the Securities Exchange Act of 19347

          Yes ____ No ____

          If an equity owner is an entity described in paragraphs (h) or (j)
          under this Item 2, please provide the information required by such
          paragraph.

     (l)  Set forth in the space provided below the (i) state(s), if any, in the
          United States in which you maintained your principal office during the
          past two years and the dates during which you maintained your office
          in each state, (ii) the state(s), if any, in which you are
          incorporated or otherwise organized, -and (iii) the state(s), if any,
          in which you still pay income taxes:

          ------------------------------------

          ------------------------------------

          ------------------------------------

                                       4.

<PAGE>   18

     The undersigned hereby represents that all the information supplied herein
is true, correct and complete as of the date hereof. The undersigned agrees to
notify Cooley Godward LLP immediately of any material change in the forgoing
answers. In connection with his, her or its purchase of securities, the
undersigned hereby further represents, warrants and certifies as follows:

     (a)  That the undersigned has adequate means of providing for his, her or
its current needs and personal contingencies, that the undersigned has no need
now, and anticipates no need in the foreseeable future, to sell the securities,
and the undersigned currently has sufficient financial liquidity to afford a
complete loss of my investment in the Company.

     (b)  That the undersigned's overall commitment to investments which are not
readily marketable is not disproportionate to the undersigned's net worth and my
investment in the securities will not cause such overall commitment to become
excessive.

     (c)  That all information which the undersigned has provided (or will
provide) concerning the undersigned and its financial position, is correct and
complete as of the date set forth below (or will be correct and complete as of
the date when provided) and, if there should be any material change in such
information prior to the undersigned having made its investment in the Company,
the undersigned will immediately provide such information to the Company.

     (d)  That the undersigned has received and carefully reviewed descriptive
materials relating to the Company and any other materials relating thereto that
the undersigned has requested.

     (e)  That the undersigned has had an opportunity to ask questions of and
receive answers from the authorized representatives of the Company, and to
review any relevant documents and records concerning the business of the Company
and the terms and conditions of this investment, and that any such questions
have been answered to the undersigned's full satisfaction.

     (f)  That no person or entity, other than the Company or its authorized
representatives, has offered the securities to the undersigned.

     (g)  That the undersigned has such knowledge and experience in financial
and business matters so that the undersigned is capable of evaluating the merits
and risks of an investment in the Company, or the undersigned or the
undersigned's financial and investment advisors together have such knowledge and
experience in financial and business matters that the undersigned is capable of
evaluating the merits and risks of an investment in the Company.

     (h)  That the securities for which the undersigned is completing this
Investor Certificate will be acquired for the undersigned's own account for
investment and not with a view toward subdivision, resale, or redistribution
thereof in a manner prohibited under the Securities Act of 1933, as amended (the
"Act"), and the undersigned does not presently have any reason to anticipate any
change in my circumstances or other particular occasion or event which

                                       5.

<PAGE>   19

would cause the undersigned has to sell such securities. The undersigned has no
contract, undertaking, agreement, understanding, or arrangement with any person
to sell, transfer, or pledge to any person any part or all of the securities
which the undersigned is acquiring, or any interest therein, and have no present
plans to enter into the same.

     (i)  That it has been called to the undersigned's attention in connection
with an investment in the Company that such investment is speculative in nature
and involves a high degree of risk.

     (j)  That the undersigned understand that no federal or state agency has
passed upon or made any recommendation or endorsement of an investment in the
securities.

THE UNDERSIGNED UNDERSTANDS AND ACKNOWLEDGES THAT THE UNDERSIGNED'S SIGNATURE TO
THIS INVESTOR QUESTIONNAIRE SHALL CONSTITUTE THE UNDERSIGNED'S SIGNATURE PAGE TO
THE STOCK PURCHASE AGREEMENT AND THE REGISTRATION RIGHTS AGREEMENTS, AND IF
ACCEPTED BY THE COMPANY, WILL CONSTITUTE A LEGALLY BINDING OBLIGATION OF THE
UNDERSIGNED; PROVIDED, HOWEVER, IF THE COMPANY DOES NOT ACCEPT THE FOLLOWING
SIGNATURE PAGE, THE FOLLOWING SIGNATURE PAGE SHALL BE VOID.

                                       6.

<PAGE>   20

                         SIGNATURE PAGE FOR THE INVESTOR
                     QUESTIONNAIRE, STOCK PURCHASE AGREEMENT
                        AND REGISTRATION RIGHTS AGREEMENT

     The undersigned Purchaser hereby executes the Investor Questionnaire, Stock
Purchase Agreement and the Registration Rights Agreement with Coulter
Pharmaceutical, Inc. (the "Company" ) and hereby authorizes this signature page
to be attached to a counterpart of such documents executed by a duly authorized
officer of the Company.

NUMBER OF SHARES
TO BE PURCHASED:
                ----------------------  ----------------------------------------
                                        NAME OF PURCHASER
                                        (PLEASE TYPE OR PRINT)

U.S. TAXPAYER ID NO., IF ANY:

                                        By
--------------------------------------    --------------------------------------
                                          Title:
                                                --------------------------------
                                          Address:
                                                  ------------------------------

                                                  ------------------------------

                                                  ------------------------------

Please set out below your registration requirements. IF SHARES ARE TO BE
REGISTERED IN THE NAME OF MORE THAN ONE ENTITY, PROVIDE THE INFORMATION
REQUESTED BELOW FOR EACH ENTITY. (PLEASE USE MULTIPLE PAGES, ONE FOR EACH
ENTITY.)

NAME IN WHICH SHARES
ARE TO BE REGISTERED:
                     -----------------------------------------------------------
NUMBER OF SHARES TO
BE PURCHASED:
             -------------------------------------------------------------------
ADDRESS OF REGISTERED HOLDER
(IF DIFFERENT FROM ABOVE):
                          ------------------------------------------------------

                          ------------------------------------------------------

NUMBER OF SHARES OF THE COMPANY'S
COMMON STOCK CURRENTLY HELD BY THE ABOVE NAMED ENTITY:
                                                      --------------------------
CONTACT NAME AND TELEPHONE
NUMBER REGARDING SETTLEMENT
AND REGISTRATION:
     Name
         -----------------------------------------------------------------------

     Telephone Number
                     -----------------------------------------------------------

                                       7.

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