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                                                                    EXHIBIT 10.2






                                 DIADEXUS, INC.

                           2000 EQUITY INCENTIVE PLAN
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                                TABLE OF CONTENTS

<TABLE>
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                                                                               Page
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<S>  <C>                                                                       <C>
1.   PURPOSES OF THE PLAN......................................................  1
2.   DEFINITIONS...............................................................  1
3.   STOCK SUBJECT TO THE PLAN.................................................  4
4.   ADMINISTRATION OF THE PLAN................................................  4
5.   ELIGIBILITY...............................................................  6
6.   LIMITATIONS...............................................................  6
7.   TERM OF PLAN..............................................................  7
8.   TERM OF OPTION............................................................  7
9.   OPTION EXERCISE PRICE AND CONSIDERATION...................................  7
10.  EXERCISE OF OPTION........................................................  8
11.  NON-TRANSFERABILITY OF OPTIONS AND STOCK
     PURCHASE RIGHTS........................................................... 11
12.  STOCK PURCHASE RIGHTS..................................................... 11
13.  ADJUSTMENTS UPON CHANGES IN CAPITALIZATION,
     MERGER OR ASSET SALE...................................................... 12
14.  TIME OF GRANTING OPTIONS AND STOCK PURCHASE
     RIGHTS.................................................................... 14
15.  AMENDMENT AND TERMINATION OF THE PLAN..................................... 14
16.  STOCKHOLDER APPROVAL...................................................... 14
17.  INABILITY TO OBTAIN AUTHORITY............................................. 15
18.  RESERVATION OF SHARES..................................................... 15
19.  INFORMATION TO HOLDERS AND PURCHASERS..................................... 15
20.  REPURCHASE PROVISIONS..................................................... 15
21.  INVESTMENT INTENT......................................................... 16
22.  GOVERNING LAW............................................................. 16
</TABLE>



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                                 DIADEXUS, INC.

                           2000 EQUITY INCENTIVE PLAN


        1. Purposes of the Plan. The purposes of the diaDexus, Inc. 2000 Equity
Incentive Plan are to attract and retain the best available personnel for
positions of substantial responsibility, to 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
Non-Qualified 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 the Committee responsible
for conducting the general administration of the Plan, as applicable, in
accordance with Section 4 hereof.

                (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
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,
or any successor statute or statutes thereto. Reference to any particular Code
section shall include any successor section.

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

                (f) "Common Stock" means the Common Stock of the Company, par
value $0.01 per share.

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

                (h) "Consultant" means any consultant or adviser if: (i) the
consultant or adviser renders bona fide services to the Company or any Parent or
Subsidiary of the Company; (ii) the services rendered by the consultant or
adviser are not in connection with the offer or sale of securities in a
capital-raising transaction and do not directly or indirectly promote or
maintain a market for the Company's securities; and (iii) the consultant or
adviser is a natural person who has contracted directly with the Company or any
Parent or Subsidiary of the Company to render such services.

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

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                (j) "Employee" means any person, including an Officer or
Director, who is an employee (as defined in accordance with Section 3401(c) of
the Code) of 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 (90)
days, unless reemployment upon expiration of such leave is guaranteed by statute
or contract. Neither service as a Director nor payment of a director's fee by
the Company shall be sufficient, by itself, to constitute "employment" by the
Company.

                (k) "Exchange Act" means the Securities Exchange Act of 1934, as
amended, or any successor statute or statutes thereto. Reference to any
particular Exchange Act section shall include any successor section.

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

                        (i) If the Common Stock is listed on any established
stock exchange or a national market system, including, without limitation, the
Nasdaq National Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market,
its Fair Market Value shall be the closing sales price for a share of 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, its Fair
Market Value shall be the mean between the high bid and low asked prices for a
share of the Common Stock on the last market trading day prior to the day of
determination; or

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

                (m) "Holder" means a person who has been granted or awarded an
Option or Stock Purchase Right or who holds Shares acquired pursuant to the
exercise of an Option or Stock Purchase Right.

                (n) "Incentive Stock Option" means an Option intended to qualify
as an incentive stock option within the meaning of Section 422 of the Code and
which is designated as an Incentive Stock Option by the Administrator.

                (o) "Independent Director" means a Director who is not an
Employee of the Company.

                (p) "Non-Qualified Stock Option" means an Option (or portion
thereof) that is not designated as an Incentive Stock Option by the
Administrator, or which is designated as an



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Incentive Stock Option by the Administrator but fails to qualify as an incentive
stock option within the meaning of Section 422 of the Code.

                (q) "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.

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

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

                (t) "Parent" means any corporation, whether now or hereafter
existing (other than the Company), in an unbroken chain of corporations ending
with the Company if each of the corporations other than the last corporation in
the unbroken chain owns stock possessing more than fifty percent of the total
combined voting power of all classes of stock in one of the other corporations
in such chain.

                (u) "Plan" means the diaDexus, Inc. 2000 Equity Incentive Plan.

                (v) "Public Trading Date" means the first date upon which Common
Stock of the Company is listed (or approved for listing) upon notice of issuance
on any securities exchange or designated (or approved for designation) upon
notice of issuance as a national market security on an interdealer quotation
system.

                (w) "Restricted Stock" means Shares acquired pursuant to the
exercise of an unvested Option in accordance with Section 10(h) below or
pursuant to a Stock Purchase Right granted under Section 14 below.

                (x) "Rule 16b-3" means that certain Rule 16b-3 under the
Exchange Act, as such Rule may be amended from time to time.

                (y) "Section 16(b)" means Section 16(b) of the Exchange Act, as
such Section may be amended from time to time.

                (z) "Securities Act" means the Securities Act of 1933, as
amended, or any successor statute or statutes thereto. Reference to any
particular Securities Act section shall include any successor section.

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

                (bb) "Share" means a share of Common Stock, as adjusted in
accordance with Section 13 below.

                (cc) "Stock Purchase Right" means a right to purchase Common
Stock pursuant to Section 14 below.



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                (dd) "Subsidiary" means any corporation, whether now or
hereafter existing (other than the Company), in an unbroken chain of
corporations beginning with the Company if each of the corporations other than
the last corporation in the unbroken chain owns stock possessing more than fifty
percent of the total combined voting power of all classes of stock in one of the
other corporations in such chain.

        3. Stock Subject to the Plan. Subject to the provisions of Section 13 of
the Plan, the shares of stock subject to Options or Stock Purchase Rights shall
be Common Stock, initially shares of the Company's Common Stock, par value $0.01
per share. Subject to the provisions of Section 13 of the Plan, the maximum
aggregate number of Shares which may be issued upon exercise of such Options or
Stock Purchase Rights is Four Million Seven Hundred Thousand (4,700,000) Shares.
Shares issued upon exercise of Options or Stock Purchase Rights 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, the unpurchased Shares which were subject thereto shall become available
for future grant or sale under the Plan (unless the Plan has terminated). Shares
which are delivered by the Holder or withheld by the Company upon the exercise
of an Option or Stock Purchase Right under the Plan, in payment of the exercise
price thereof or tax withholding thereon, may again be optioned, granted or
awarded hereunder, subject to the limitations of this Section 3. 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.
Notwithstanding the provisions of this Section 3, no Shares may again be
optioned, granted or awarded if such action would cause an Incentive Stock
Option to fail to qualify as an Incentive Stock Option under Code Section 422.

        4. Administration of the Plan.

                (a) Administrator. Unless and until the Board delegates
administration to a Committee as set forth below, the Plan shall be administered
by the Board. The Board may delegate administration of the Plan to a Committee
or Committees of one or more members of the Board, and the term "Committee"
shall apply to any person or persons to whom such authority has been delegated.
If administration is delegated to a Committee, the Committee shall have, in
connection with the administration of the Plan, the powers theretofore possessed
by the Board, including the power to delegate to a subcommittee any of the
administrative powers the Committee is authorized to exercise (and references in
this Plan to the Board shall thereafter be to the Committee or subcommittee),
subject, however, to such resolutions, not inconsistent with the provisions of
the Plan, as may be adopted from time to time by the Board. Notwithstanding the
foregoing, however, from and after the Public Trading Date, a Committee of the
Board shall administer the Plan and the Committee shall consist solely of two or
more Independent Directors each of whom is both an "outside director," within
the meaning of Section 162(m) of the Code, and a "non-employee director" within
the meaning of Rule 16b-3. Within the scope of such authority, the Board or the
Committee may (i) delegate to a committee of one or more members of the Board
who are not Independent Directors the authority to grant awards under the Plan
to eligible persons who are either (1) not then "covered employees," within the
meaning of Section 162(m) of the Code and are not expected to be "covered
employees" at the time of recognition of income resulting from such award or (2)
not persons with respect to whom the Company wishes to comply with Section
162(m) of the Code and/or (ii) delegate to a committee of one or more



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members of the Board who are not "non-employee directors," within the meaning of
Rule 16b-3, the authority to grant awards under the Plan to eligible persons who
are not then subject to Section 16 of the Exchange Act. The Board may abolish
the Committee at any time and revest in the Board the administration of the
Plan. Appointment of Committee members shall be effective upon acceptance of
appointment. Committee members may resign at any time by delivering written
notice to the Board. Vacancies in the Committee may only be filled by the Board.

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

                        (i) to determine the Fair Market Value;

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

                        (iii) to determine the number of Shares to be covered by
each such award granted hereunder;

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

                        (v) to determine the terms and conditions 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 vest or 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 Common Stock relating thereto, based in each case on such
factors as the Administrator, in its sole discretion, shall determine);

                        (vi) to determine whether to offer to buyout a
previously granted Option as provided in subsection 10(i) and to determine the
terms and conditions of such offer and buyout (including whether payment is to
be made in cash or Shares);

                        (vii) 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;

                        (viii) to allow Holders 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 minimum amount required to be withheld
based on the statutory withholding rates for federal and state tax purposes that
apply to supplemental taxable income. The Fair Market Value of the Shares to be
withheld shall be determined on the date that the amount of tax to be withheld
is to be determined. All elections by Holders 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;



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                        (ix) to amend the Plan or any Option or Stock Purchase
Right granted under the Plan as provided in Section 15; and

                        (x) to construe and interpret the terms of the Plan and
awards granted pursuant to the Plan and to exercise such powers and perform such
acts as the Administrator deems necessary or desirable to promote the best
interests of the Company which are not in conflict with the provisions of the
Plan.

                (c) Effect of Administrator's Decision. All decisions,
determinations and interpretations of the Administrator shall be final and
binding on all Holders.

        5. Eligibility. Non-Qualified Stock Options and Stock Purchase Rights
may be granted to Service Providers. Incentive Stock Options may be granted only
to Employees. If otherwise eligible, a Service Provider who has been granted an
Option or Stock Purchase Right may be granted additional Options or Stock
Purchase Rights.

        6. Limitations.

                (a) Each Option shall be designated by the Administrator in the
Option Agreement as either an Incentive Stock Option or a Non-Qualified Stock
Option. However, notwithstanding such designations, to the extent that the
aggregate Fair Market Value of Shares subject to a Holder's Incentive Stock
Options and other incentive stock options granted by the Company, any Parent or
Subsidiary, which become exercisable for the first time during any calendar year
(under all plans of the Company or any Parent or Subsidiary) exceeds $100,000,
such excess Options or other options shall be treated as Non-Qualified 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, and the Fair
Market Value of the Shares shall be determined as of the time of grant.

                (b) Neither the Plan, any Option nor any Stock Purchase Right
shall confer upon a Holder any right with respect to continuing the Holder's
employment or consulting relationship with the Company, nor shall they interfere
in any way with the Holder's right or the Company's right to terminate such
employment or consulting relationship at any time, with or without cause.

                (c) No Service Provider shall be granted, in any calendar year,
Options or Stock Purchase Rights to purchase more than 1,500,000 Shares;
provided, however, that the foregoing limitation shall not apply prior to the
Public Trading Date and, following the Public Trading Date, the foregoing
limitation shall not apply until the earliest of: (i) the first material
modification of the Plan (including any increase in the number of shares
reserved for issuance under the Plan in accordance with Section 3); (ii) the
issuance of all of the shares of Common Stock reserved for issuance under the
Plan; (iii) the expiration of the Plan; (iv) the first meeting of stockholders
at which Directors of the Company are to be elected that occurs after the close
of the third calendar year following the calendar year in which occurred the
first registration of an equity security of the Company under Section 12 of the
Exchange Act; or (v) such other date



                                       6
<PAGE>   9

required by Section 162(m) of the Code and the rules and regulations promulgated
thereunder. The foregoing limitation shall be adjusted proportionately in
connection with any change in the Company's capitalization as described in
Section 13. For purposes of this Section 6(c), if an Option is canceled in the
same calendar year it was granted (other than in connection with a transaction
described in Section 13), the canceled Option will be counted against the limit
set forth in this Section 6(c). For this purpose, if the exercise price of an
Option is reduced, the transaction shall be treated as a cancellation of the
Option and the grant of a new Option.

                7. Term of Plan. The Plan shall become effective upon its
initial adoption by the Board and shall continue in effect until it is
terminated under Section 15 of the Plan. No Options or Stock Purchase Rights may
be issued under the Plan after the tenth (10th) anniversary of the earlier of
(i) the date upon which the Plan is adopted by the Board or (ii) the date the
Plan is approved by the stockholders.

                8. Term of Option. The term of each Option shall be stated in
the Option Agreement; provided, however, that the term shall be no more than ten
(10) years from the date of grant thereof. In the case of an Incentive Stock
Option granted to a Holder who, at the time the Option is granted, owns (or is
treated as owning under Code Section 424) 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 term of the 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) Except as provided in Section 13, the per share exercise
price for the Shares to be issued upon exercise of an Option shall be such price
as is determined by the Administrator, but shall be subject to the following:

                        (i) In the case of an Incentive Stock Option

                                (A) granted to an Employee who, at the time of
grant of such Option, owns (or is treated as owning under Code Section 424)
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 one hundred ten percent (110%) of the Fair
Market Value per Share on the date of grant.

                                (B) granted to any other Employee, the per Share
exercise price shall be no less than one hundred percent (100%) of the Fair
Market Value per Share on the date of grant.

                        (ii) In the case of a Non-Qualified Stock Option

                                (A) granted to a Service Provider who, at the
time of grant of such Option, 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 exercise price shall be no less than one hundred ten percent
(110%) of the Fair Market Value per Share on the date of the grant.



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                                (B) granted to any other Service Provider, the
per Share exercise price shall be no less than eighty-five percent (85%) 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 other than as required above pursuant to
a merger or other corporate transaction.

                (b) The consideration to be paid for the Shares to be issued
upon exercise of an Option, including the method of payment, shall be determined
by the Administrator (and, in the case of an Incentive Stock Option, shall be
determined at the time of grant). Such consideration may consist of (1) cash,
(2) check, (3) with the consent of the Administrator, a full recourse promissory
note bearing interest (at no less than such rate as shall then preclude the
imputation of interest under the Code) and payable upon such terms as may be
prescribed by the Administrator, (4) with the consent of the Administrator,
other Shares which (x) in the case of Shares acquired from the Company, have
been owned by the Holder for more than six (6) months on the date of surrender,
and (y) have a Fair Market Value on the date of surrender equal to the aggregate
exercise price of the Shares as to which such Option shall be exercised, (5)
with the consent of the Administrator, surrendered Shares then issuable upon
exercise of the Option having a Fair Market Value on the date of exercise equal
to the aggregate exercise price of the Option or exercised portion thereof, (6)
with the consent of the Administrator, property of any kind which constitutes
good and valuable consideration, (7) with the consent of the Administrator,
delivery of a notice that the Holder has placed a market sell order with a
broker with respect to Shares then issuable upon exercise of the Options and
that the broker has been directed to pay a sufficient portion of the net
proceeds of the sale to the Company in satisfaction of the Option exercise
price, provided, that payment of such proceeds is then made to the Company upon
settlement of such sale, or (8) with the consent of the Administrator, any
combination of the foregoing methods of payment.

        10. Exercise of Option.

                (a) Vesting; Fractional Exercises. Except as provided in Section
13, Options granted hereunder shall be vested and exercisable according to the
terms hereof at such times and under such conditions as determined by the
Administrator and set forth in the Option Agreement; provided, however, that,
except with regard to Options granted to Officers, Directors or Consultants, in
no event shall an Option granted hereunder become vested and exercisable at a
rate of less than twenty percent (20%) per year over five (5) years from the
date the Option is granted, subject to reasonable conditions, such as continuing
to be a Service Provider. An Option may not be exercised for a fraction of a
Share.

                (b) Deliveries upon Exercise. All or a portion of an exercisable
Option shall be deemed exercised upon delivery of all of the following to the
Secretary of the Company or his or her office:

                        (i) A written or electronic notice complying with the
applicable rules established by the Administrator stating that the Option, or a
portion thereof, is exercised. The



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<PAGE>   11

notice shall be signed or transmitted electronically, as applicable, by the
Holder or other person then entitled to exercise the Option or such portion of
the Option;

                        (ii) Such representations and documents as the
Administrator, in its sole discretion, deems necessary or advisable to effect
compliance with Applicable Laws. The Administrator may, in its sole discretion,
also take whatever additional actions it deems appropriate to effect such
compliance, including, without limitation, placing legends on share certificates
and issuing stop transfer notices to agents and registrars;

                        (iii) Upon the exercise of all or a portion of an
unvested Option pursuant to Section 10(h), a Restricted Stock purchase agreement
in a form determined by the Administrator and signed by the Holder or other
person then entitled to exercise the Option or such portion of the Option; and

                        (iv) In the event that the Option shall be exercised
pursuant to Section 10(f) by any person or persons other than the Holder,
appropriate proof of the right of such person or persons to exercise the Option.

                (c) Conditions to Delivery of Share Certificates. The Company
shall not be required to issue or deliver any certificate or certificates for
Shares purchased upon the exercise of any Option or portion thereof prior to
fulfillment of all of the following conditions:

                        (i) The admission of such Shares to listing on all stock
exchanges on which such class of stock is then intended to be listed;

                        (ii) The completion of any registration or other
qualification of such Shares under any state or federal law, or under the
rulings or regulations of the Securities and Exchange Commission or any other
governmental regulatory body which the Administrator shall, in its sole
discretion, deem necessary or advisable;

                        (iii) The obtaining of any approval or other clearance
from any state or federal governmental agency which the Administrator shall, in
its sole discretion, determine to be necessary or advisable;

                        (iv) The lapse of such reasonable period of time
following the exercise of the Option as the Administrator may establish from
time to time for reasons of administrative convenience; and

                        (v) The receipt by the Company of full payment for such
Shares, including payment of any applicable withholding tax, which in the sole
discretion of the Administrator may be in the form of consideration used by the
Holder to pay for such Shares under Section 9(b).

                (d) Termination of Relationship as a Service Provider. If a
Holder ceases to be a Service Provider other than by reason of the Holder's
disability or death, such Holder 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; provided, however, that prior to



                                       9
<PAGE>   12

the Public Trading Date, such period of time shall not be less than thirty (30)
days (but in no event later than the expiration of the term of the 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 Holder's termination. If, on the date of termination, the Holder is not
vested as to his or her entire Option, the Shares covered by the unvested
portion of the Option immediately cease to be issuable under the Option and
shall again become available for issuance under the Plan. If, after termination,
the Holder does not exercise his or her Option within the time period specified
herein, the Option shall terminate, and the Shares covered by such Option shall
again become available for issuance under the Plan.

                (e) Disability of Holder. If a Holder ceases to be a Service
Provider as a result of the Holder's disability, the Holder 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; provided, however,
that prior to the Public Trading Date, such period of time shall not be less
than six (6) months (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 Holder's termination. If such disability is not a
"disability" as such term is defined in Section 22(e)(3) of the Code, in the
case of an Incentive Stock Option such Incentive Stock Option shall
automatically cease to be treated as an Incentive Stock Option and shall be
treated for tax purposes as a Non-Qualified Stock Option from and after the day
which is three (3) months and one (1) day following such termination. If, on the
date of termination, the Holder is not vested as to his or her entire Option,
the Shares covered by the unvested portion of the Option shall immediately cease
to be issuable under the Option and shall again become available for issuance
under the Plan. If, after termination, the Holder does not exercise his or her
Option within the time specified herein, the Option shall terminate, and the
Shares covered by such Option shall again become available for issuance under
the Plan.

                (f) Death of Holder. If a Holder dies while a Service Provider,
the Option may be exercised within such period of time as is specified in the
Option Agreement provided, however, that prior to the Public Trading Date, such
period of time shall not be less than six (6) months (but in no event later than
the expiration of the term of such Option as set forth in the Notice of Grant),
by the Holder's estate or by a person who acquires the right to exercise the
Option by bequest or inheritance, but only to the extent that the Option is
vested on the date of death. In the absence of a specified time in the Option
Agreement, the Option shall remain exercisable for twelve (12) months following
the Holder's termination. If, at the time of death, the Holder is not vested as
to his or her entire Option, the Shares covered by the unvested portion of the
Option shall immediately cease to be issuable under the Option and shall again
become available for issuance under the Plan. The Option may be exercised by the
executor or administrator of the Holder's estate or, if none, by the person(s)
entitled to exercise the Option under the Holder'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
again become available for issuance under the Plan.

                (g) Regulatory Extension. A Holder's Option Agreement may
provide that if the exercise of the Option following the termination of the
Holder's status as a Service Provider



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<PAGE>   13

(other than upon the Holder's death or Disability) would be prohibited at any
time solely because the issuance of shares would violate the registration
requirements under the Securities Act, then the Option shall terminate on the
earlier of (i) the expiration of the term of the Option set forth in Section 8
or (ii) the expiration of a period of three (3) months after the termination of
the Holder's status as a Service Provider during which the exercise of the
Option would not be in violation of such registration requirements.

                (h) Early Exercisability. The Administrator may provide in the
terms of a Holder's Option Agreement that the Holder may, at any time before the
Holder's status as a Service Provider terminates, exercise the Option in whole
or in part prior to the full vesting of the Option; provided, however, that
subject to Section 20, Shares acquired upon exercise of an Option which has not
fully vested may be subject to any forfeiture, transfer or other restrictions as
the Administrator may determine in its sole discretion.

                (i) Buyout Provisions. The Administrator may at any time offer
to buyout 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 Holder at the time that such offer is made.

        11. Non-Transferability of Options and Stock Purchase Rights. Options
and Stock Purchase Rights 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 Holder,
only by the Holder.

        12. Stock Purchase Rights.

                (a) Rights to Purchase. Stock Purchase Rights may be issued
either alone, in addition to, or in tandem with Options 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 of the terms, conditions and restrictions related to the
offer, including the number of Shares that such person shall be entitled to
purchase, the price to be paid, and the time within which such person 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 Right. Unless the Administrator determines
otherwise, the Restricted Stock purchase agreement shall grant the Company the
right to repurchase Shares acquired upon exercise of a Stock Purchase Right upon
the termination of the purchaser's status as a Service Provider for any reason.
Subject to Section 20, the purchase price for Shares repurchased by the Company
pursuant to such repurchase right and the rate at which such repurchase right
shall lapse shall be determined by the Administrator in its sole discretion, and
shall be set forth in the Restricted Stock purchase agreement.

                (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.



                                       11
<PAGE>   14

                (d) Rights as a Shareholder. Once the Stock Purchase Right is
exercised, the purchaser shall have rights equivalent to those of a shareholder
and shall be a shareholder when his or her purchase is entered upon the records
of the duly authorized transfer agent of the Company. No adjustment shall 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.

        13. Adjustments upon Changes in Capitalization, Merger or Asset Sale.

                (a) In the event that the Administrator determines that any
dividend or other distribution (whether in the form of cash, Common Stock, other
securities, or other property), recapitalization, reclassification, stock split,
reverse stock split, reorganization, merger, consolidation, split-up, spin-off,
combination, repurchase, liquidation, dissolution, or sale, transfer, exchange
or other disposition of all or substantially all of the assets of the Company,
or exchange of Common Stock or other securities of the Company, issuance of
warrants or other rights to purchase Common Stock or other securities of the
Company, or other similar corporate transaction or event, in the Administrator's
sole discretion, affects the Common Stock such that an adjustment is determined
by the Administrator to be appropriate in order to prevent dilution or
enlargement of the benefits or potential benefits intended by the Company to be
made available under the Plan or with respect to any Option, Stock Purchase
Right or Restricted Stock, then the Administrator shall, in such manner as it
may deem equitable, adjust any or all of:

                        (i) the number and kind of shares of Common Stock (or
other securities or property) with respect to which Options or Stock Purchase
Rights may be granted or awarded (including, but not limited to, adjustments of
the limitations in Section 3 on the maximum number and kind of shares which may
be issued and adjustments of the maximum number of Shares that may be purchased
by any Holder in any calendar year pursuant to Section 6(c));

                        (ii) the number and kind of shares of Common Stock (or
other securities or property) subject to outstanding Options, Stock Purchase
Rights or Restricted Stock; and

                        (iii) the grant or exercise price with respect to any
Option or Stock Purchase Right.

        (b) In the event of any transaction or event described in Section 13(a),
the Administrator, in its sole discretion, and on such terms and conditions as
it deems appropriate, either by the terms of the Option, Stock Purchase Right or
Restricted Stock or by action taken prior to the occurrence of such transaction
or event and either automatically or upon the Holder's request, is hereby
authorized to take any one or more of the following actions whenever the
Administrator determines that such action is appropriate in order to prevent
dilution or enlargement of the benefits or potential benefits intended by the
Company to be made available under the Plan or with respect to any Option, Stock
Purchase Right or Restricted Stock granted or issued under the Plan or to
facilitate such transaction or event:



                                       12
<PAGE>   15

                        (i) To provide for either the purchase of any such
Option, Stock Purchase Right or Restricted Stock for an amount of cash equal to
the amount that could have been obtained upon the exercise of such Option or
Stock Purchase Right or realization of the Holder's rights had such Option,
Stock Purchase Right or Restricted Stock been currently exercisable or payable
or fully vested or the replacement of such Option, Stock Purchase Right or
Restricted Stock with other rights or property selected by the Administrator in
its sole discretion;

                        (ii) To provide that such Option or Stock Purchase Right
shall be exercisable as to all shares covered thereby, notwithstanding anything
to the contrary in the Plan or the provisions of such Option or Stock Purchase
Right;

                        (iii) To provide that such Option, Stock Purchase Right
or Restricted Stock be assumed by the successor or survivor corporation, or a
parent or subsidiary thereof, or shall be substituted for by similar options,
rights or awards covering the stock of the successor or survivor corporation, or
a parent or subsidiary thereof, with appropriate adjustments as to the number
and kind of shares and prices;

                        (iv) To make adjustments in the number and type of
shares of Common Stock (or other securities or property) subject to outstanding
Options and Stock Purchase Rights, and/or in the terms and conditions of
(including the grant or exercise price), and the criteria included in,
outstanding Options, Stock Purchase Rights or Restricted Stock or Options, Stock
Purchase Rights or Restricted Stock which may be granted in the future; and

                        (v) To provide that immediately upon the consummation of
such event, such Option or Stock Purchase Right shall not be exercisable and
shall terminate; provided, that for a specified period of time prior to such
event, such Option or Stock Purchase Right shall be exercisable as to all Shares
covered thereby, and the restrictions imposed under an Option Agreement or
Restricted Stock purchase agreement upon some or all Shares may be terminated
and, in the case of Restricted Stock, some or all shares of such Restricted
Stock may cease to be subject to repurchase, notwithstanding anything to the
contrary in the Plan or the provisions of such Option, Stock Purchase Right or
Restricted Stock purchase agreement.

                (c) Subject to Section 3, the Administrator may, in its sole
discretion, include such further provisions and limitations in any Option, Stock
Purchase Right, Restricted Stock agreement or certificate, as it may deem
equitable and in the best interests of the Company.

                (d) Notwithstanding the foregoing, in the event that the Company
becomes a party to a transaction that is intended to qualify for "pooling of
interests" accounting treatment and, but for one or more of the provisions of
this Plan or any Option Agreement or any Restricted Stock purchase agreement
would so qualify, then this Plan and any such agreement shall be interpreted so
as to preserve such accounting treatment, and to the extent that any provision
of the Plan or any such agreement would disqualify the transaction from pooling
of interests accounting treatment (including, if applicable, an entire Option
Agreement or Restricted Stock purchase agreement), then such provision shall be
null and void. All determinations to be made in connection with the preceding
sentence shall be made by the independent accounting firm



                                       13
<PAGE>   16

whose opinion with respect to "pooling of interests" treatment is required as a
condition to the Company's consummation of such transaction.

                (e) The existence of the Plan, any Option Agreement or
Restricted Stock purchase agreement and the Options or Stock Purchase Rights
granted hereunder shall not affect or restrict in any way the right or power of
the Company or the stockholders of the Company to make or authorize any
adjustment, recapitalization, reorganization or other change in the Company's
capital structure or its business, any merger or consolidation of the Company,
any issue of stock or of options, warrants or rights to purchase stock or of
bonds, debentures, preferred or prior preference stocks whose rights are
superior to or affect the Common Stock or the rights thereof or which are
convertible into or exchangeable for Common Stock, or the dissolution or
liquidation of the Company, or any sale or transfer of all or any part of its
assets or business, or any other corporate act or proceeding, whether of a
similar character or otherwise.

        14. Time of Granting Options and Stock Purchase Rights. The date of
grant of an Option or Stock Purchase Right shall, for all purposes, be the date
on which the Administrator makes the determination granting such Option or Stock
Purchase Right, or such other date as is determined by the Administrator. Notice
of the determination shall be given to each Employee or Consultant to whom an
Option or Stock Purchase Right is so granted 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 wholly
or partially amend, alter, suspend or terminate the Plan. However, without
approval of the Company's stockholders given within twelve (12) months before or
after the action by the Board, no action of the Board may, except as provided in
Section 13, increase the limits imposed in Section 3 on the maximum number of
Shares which may be issued under the Plan or extend the term of the Plan under
Section 7.

                (b) Stockholder Approval. The Board shall obtain stockholder
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
Holder, unless mutually agreed otherwise between the Holder and the
Administrator, which agreement must be in writing and signed by the Holder 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,
Stock Purchase Rights or Restricted Stock granted or awarded under the Plan
prior to the date of such termination.

        16. Stockholder Approval. The Plan will be submitted for the approval of
the Company's stockholders within twelve (12) months after the date of the
Board's initial adoption of the Plan. Options, Stock Purchase Rights or
Restricted Stock may be granted or awarded prior to such stockholder approval,
provided that such Options, Stock Purchase Rights and Restricted Stock shall not
be exercisable, shall not vest and the restrictions thereon shall not lapse
prior to



                                       14
<PAGE>   17

the time when the Plan is approved by the stockholders, and provided further
that if such approval has not been obtained at the end of said twelve-month
period, all Options, Stock Purchase Rights and Restricted Stock previously
granted or awarded under the Plan shall thereupon be canceled and become null
and void.

        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,
shall at all times reserve and keep available such number of Shares as shall be
sufficient to satisfy the requirements of the Plan.

        19. Information to Holders and Purchasers. Prior to the Public Trading
Date and to the extent required by Section 260.140.46 of Title 10 of the
California Code of Regulations, the Company shall provide to each Holder and to
each individual who acquires Shares pursuant to the Plan, not less frequently
than annually during the period such Holder or purchaser has one or more Options
or Stock Purchase Rights outstanding, and, in the case of an individual who
acquires Shares pursuant to the Plan, during the period such individual owns
such Shares, copies of annual financial statements. Notwithstanding the
preceding sentence, the Company shall not be required to provide such statements
to key employees whose duties in connection with the Company assure their access
to equivalent information.

        20. Repurchase Provisions. The Administrator in its sole discretion may
provide that the Company may repurchase Shares acquired upon exercise of an
Option or Stock Purchase Right upon the occurrence of certain specified events,
including, without limitation, a Holder's termination as a Service Provider,
divorce, bankruptcy or insolvency; provided, however, that any such repurchase
right shall be set forth in the applicable Option Agreement or Restricted Stock
purchase agreement or in another agreement referred to in such agreement and,
provided further, that to the extent required by Section 260.140.41 and Section
260.140.42 of Title 10 of the California Code of Regulations, any such
repurchase right set forth in an Option or Stock Purchase Right granted prior to
the Public Trading Date to a person who is not an Officer, Director or
Consultant shall be upon the following terms: (i) if the repurchase option gives
the Company the right to repurchase the shares upon termination as a Service
Provider at not less than the Fair Market Value of the shares to be purchased on
the date of termination of status as a Service Provider, then (A) the right to
repurchase shall be exercised for cash or cancellation of purchase money
indebtedness for the shares within ninety (90) days of termination of status as
a Service Provider (or in the case of shares issued upon exercise of Options or
Stock Purchase Rights after such date of termination, within ninety (90) days
after the date of the exercise) or such longer period as may be agreed to by the
Administrator and the Plan participant and (B) the right terminates when the
shares become publicly traded; and (ii) if the repurchase option gives the
Company the right to repurchase the Shares upon termination as a Service
Provider at the original purchase price for such Shares, then (A) the right to
repurchase at the original purchase price shall lapse at the rate of at least
twenty percent (20%) of the shares per year over five (5)



                                       15
<PAGE>   18

years from the date the Option or Stock Purchase Right is granted (without
respect to the date the Option or Stock Purchase Right was exercised or became
exercisable) and (B) the right to repurchase shall be exercised for cash or
cancellation of purchase money indebtedness for the shares within ninety (90)
days of termination of status as a Service Provider (or, in the case of shares
issued upon exercise of Options or Stock Purchase Rights, after such date of
termination, within ninety (90) days after the date of the exercise) or such
longer period as may be agreed to by the Company and the Plan participant.

        21. Investment Intent. The Company may require a Plan participant, as a
condition of exercising or acquiring stock under any Option or Stock Purchase
Right, (i) to give written assurances satisfactory to the Company as to the
participant's knowledge and experience in financial and business matters and/or
to employ a purchaser representative reasonably satisfactory to the Company who
is knowledgeable and experienced in financial and business matters and that he
or she is capable of evaluating, alone or together with the purchaser
representative, the merits and risks of exercising the Option or Stock Purchase
Right; and (ii) to give written assurances satisfactory to the Company stating
that the participant is acquiring the stock subject to the Option or Stock
Purchase Right for the participant's own account and not with any present
intention of selling or otherwise distributing the stock. The foregoing
requirements, and any assurances given pursuant to such requirements, shall be
inoperative if (A) the issuance of the shares upon the exercise or acquisition
of stock under the applicable Option or Stock Purchase Right has been registered
under a then currently effective registration statement under the Securities Act
or (B) as to any particular requirement, a determination is made by counsel for
the Company that such requirement need not be met in the circumstances under the
then applicable securities laws. The Company may, upon advice of counsel to the
Company, place legends on stock certificates issued under the Plan as such
counsel deems necessary or appropriate in order to comply with applicable
securities laws, including, but not limited to, legends restricting the transfer
of the stock.

        22. Governing Law. The validity and enforceability of this Plan shall be
governed by and construed in accordance with the laws of the State of Delaware
without regard to otherwise governing principles of conflicts of law.

                                  * * * * * * *

                I hereby certify that the Plan was duly adopted by the Board of
Directors of diaDexus, Inc. on __________ ___, 2000.

                Executed at __________, _____________ on this ____ day of
__________, 2000.


                                       Name:
                                             -----------------------------------
                                       Title:
                                              ----------------------------------

                                  * * * * * * *



                                       16
<PAGE>   19

                I hereby certify that the foregoing Plan was approved by the
stockholders of diaDexus, Inc. on _____________.

                Executed at __________, ____________ on this ____ day of
___________, 2000.





                                       -----------------------------------------
                                       Secretary



                                       17