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                                                                    EXHIBIT 10.5

                               MEDIBUY.COM, INC.
                           STOCK OPTION GRANT NOTICE
                           (1999 OMNIBUS EQUITY PLAN)


medibuy.com, Inc. (the "Company"), pursuant to its 1999 Omnibus Equity Plan (the
"Plan"), hereby grants to Optionholder an option to purchase the number of
shares of the Company's Common Stock set forth below. This option is subject to
all of the terms and conditions as set forth herein and in the Stock Option
Agreement, the Plan and the Notice of Exercise, all of which are attached hereto
and incorporated herein in their entirety.

Optionholder:                              _____________________________________
Date of Grant:                             _____________________________________
Vesting Commencement Date:                 _____________________________________
Number of Shares Subject to Option:        _____________________________________
Exercise Price (Per Share):                _____________________________________
Total Exercise Price:                      _____________________________________
Expiration Date:                           _____________________________________

TYPE OF GRANT:     [ ]  Incentive Stock Option   [ ]   Nonstatutory Stock Option

EXERCISE SCHEDULE: [ ]  Same as Vesting Schedule [ ]   Early Exercise Permitted

VESTING SCHEDULE:  1/4th  of the shares vest one year after the Vesting
                   Commencement Date.
                   1/48th of the shares vest monthly thereafter over the next
                   three years.

PAYMENT:           By one or a  combination  of the  following  items
                   (described in the Stock Option Agreement):

                        By cash or check
                        Pursuant to a Regulation T Program if the Shares are
                        publicly traded
                        By delivery of already-owned shares if the Shares are
                        publicly traded


ADDITIONAL TERMS/ACKNOWLEDGEMENTS: The undersigned Optionholder acknowledges
receipt of, and understands and agrees to, this Grant Notice, the Stock Option
Agreement and the Plan. Optionholder further acknowledges that as of the Date of
Grant, this Grant Notice, the Stock Option Agreement and the Plan set forth the
entire understanding between Optionholder and the Company regarding the
acquisition of stock in the Company and supersede all prior oral and written
agreements on that subject with the exception of (i) options previously granted
and delivered to Optionholder under the Plan, and (ii) the following agreements
only:

        OTHER AGREEMENTS:               ________________________________________

                                        ________________________________________

MEDIBUY.COM, INC.                                  OPTIONHOLDER:


By:________________________________     ________________________________________
              Signature                                Signature

Title:_____________________________     Date:___________________________________

Date:______________________________

ATTACHMENTS: Stock Option Agreement, 1999 Omnibus Equity Plan and Notice of
Exercise


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                                MEDIBUY.COM, INC.
                            1999 OMNIBUS EQUITY PLAN

                             STOCK OPTION AGREEMENT
                   (INCENTIVE AND NONSTATUTORY STOCK OPTIONS)


        Pursuant to your Stock Option Grant Notice ("Grant Notice") and this
Stock Option Agreement, medibuy.com, Inc. (the "Company") has granted you an
option under its 1999 Omnibus Equity Plan (the "Plan") to purchase the number of
shares of the Company's Common Stock indicated in your Grant Notice at the
exercise price indicated in your Grant Notice. Defined terms not explicitly
defined in this Stock Option Agreement but defined in the Plan shall have the
same definitions as in the Plan.

        The details of your option are as follows:

        1. VESTING. Subject to the limitations contained herein, your option
will vest as provided in your Grant Notice, provided that vesting will cease
upon the termination of your Continuous Service.

        2. NUMBER OF SHARES AND EXERCISE PRICE. The number of shares of Common
Stock subject to your option and your exercise price per share referenced in
your Grant Notice may be adjusted from time to time for Capitalization
Adjustments, as provided in the Plan.

        3. EXERCISE PRIOR TO VESTING ("EARLY EXERCISE"). If permitted in your
Grant Notice (i.e., the "Exercise Schedule" indicates that "Early Exercise" of
your option is permitted) and subject to the provisions of your option, you may
elect at any time that is both (i) during the period of your Continuous Service
and (ii) during the term of your option, to exercise all or part of your option,
including the nonvested portion of your option; provided, however, that:

           (a) a partial exercise of your option shall be deemed to cover first
vested shares of Common Stock and then the earliest vesting installment of
unvested shares of Common Stock;

           (b) any shares of Common Stock so purchased from installments that
have not vested as of the date of exercise shall be subject to the purchase
option in favor of the Company as described in the Company's form of Early
Exercise Stock Purchase Agreement;

           (c) you shall enter into the Company's form of Early Exercise Stock
Purchase Agreement with a vesting schedule that will result in the same vesting
as if no early exercise had occurred; and

           (d) if your option is an incentive stock option, then, as provided in
the Plan, to the extent that the aggregate Fair Market Value (determined at the
time of grant) of the shares of Common Stock with respect to which your option
plus all other incentive stock options you hold are exercisable for the first
time by you during any calendar year (under all plans of the Company and its
Affiliates) exceeds one hundred thousand dollars ($100,000), your option(s) or



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portions thereof that exceed such limit (according to the order in which they
were granted) shall be treated as nonstatutory stock options.

        4. METHOD OF PAYMENT. Payment of the exercise price is due in full upon
exercise of all or any part of your option. You may elect to make payment of the
exercise price in cash or by check or in any other manner PERMITTED BY YOUR
GRANT NOTICE, which may include one or more of the following:

           (a) In the Company's sole discretion at the time your option is
exercised and provided that at the time of exercise the Common Stock is publicly
traded and quoted regularly in The Wall Street Journal, pursuant to a program
developed under Regulation T as promulgated by the Federal Reserve Board that,
prior to the issuance of Common Stock, results in either the receipt of cash (or
check) by the Company or the receipt of irrevocable instructions to pay the
aggregate exercise price to the Company from the sales proceeds.

           (b) Provided that at the time of exercise the Common Stock is
publicly traded and quoted regularly in The Wall Street Journal, by delivery of
already-owned shares of Common Stock either that you have held for the period
required to avoid a charge to the Company's reported earnings (generally six
months) or that you did not acquire, directly or indirectly from the Company,
that are owned free and clear of any liens, claims, encumbrances or security
interests, and that are valued at Fair Market Value on the date of exercise.
"Delivery" for these purposes, in the sole discretion of the Company at the time
you exercise your option, shall include delivery to the Company of your
attestation of ownership of such shares of Common Stock in a form approved by
the Company. Notwithstanding the foregoing, you may not exercise your option by
tender to the Company of Common Stock to the extent such tender would violate
the provisions of any law, regulation or agreement restricting the redemption of
the Company's stock.

           (c) Pursuant to the following deferred payment alternative:

               (i) Not less than one hundred percent (100%) of the aggregate
exercise price, plus accrued interest, shall be due four (4) years from date of
exercise or, at the Company's election, upon termination of your Continuous
Service.

               (ii) Interest shall be compounded at least annually and shall be
charged at the minimum rate of interest necessary to avoid the treatment as
interest, under any applicable provisions of the Code, of any portion of any
amounts other than amounts stated to be interest under the deferred payment
arrangement.

               (iii) At any time that the Company is incorporated in Delaware,
payment of the Common Stock's "par value," as defined in the Delaware General
Corporation Law, shall be made in cash and not by deferred payment.

               (iv) In order to elect the deferred payment alternative, you
must, as a part of your written notice of exercise, give notice of the election
of this payment alternative and, in order to secure the payment of the deferred
exercise price to the Company hereunder, if the Company so requests, you must
tender to the Company a promissory note and a security agreement covering the
purchased shares of Common Stock, both in form and substance



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satisfactory to the Company, or such other or additional documentation as the
Company may request.

        5. WHOLE SHARES. You may exercise your option only for whole shares of
Common Stock.

        6. SECURITIES LAW COMPLIANCE. Notwithstanding anything to the contrary
contained herein, you may not exercise your option unless the shares of Common
Stock issuable upon such exercise are then registered under the Securities Act
or, if such shares of Common Stock are not then so registered, the Company has
determined that such exercise and issuance would be exempt from the registration
requirements of the Securities Act. The exercise of your option must also comply
with other applicable laws and regulations governing your option, and you may
not exercise your option if the Company determines that such exercise would not
be in material compliance with such laws and regulations.

        7. TERM. The term of your option commences on the Date of Grant and
expires upon the EARLIEST of the following:

           (a) three (3) months after the termination of your Continuous Service
for any reason other than your Disability or death, provided that if during any
part of such three- (3-) month period your option is not exercisable solely
because of the condition set forth in the preceding paragraph relating to
"Securities Law Compliance," your option shall not expire until the earlier of
the Expiration Date or until it shall have been exercisable for an aggregate
period of three (3) months after the termination of your Continuous Service;

           (b) twelve (12) months after the termination of your Continuous
Service due to your Disability;

           (c) eighteen (18) months after your death if you die either during
your Continuous Service or within three (3) months after your Continuous Service
terminates;

           (d) the Expiration Date indicated in your Grant Notice; or

           (e) the tenth (10th) anniversary of the Date of Grant.

        If your option is an incentive stock option, note that, to obtain the
federal income tax advantages associated with an "incentive stock option," the
Code requires that at all times beginning on the date of grant of your option
and ending on the day three (3) months before the date of your option's
exercise, you must be an employee of the Company or an Affiliate, except in the
event of your death or Disability. The Company has provided for extended
exercisability of your option under certain circumstances for your benefit but
cannot guarantee that your option will necessarily be treated as an "incentive
stock option" if you continue to provide services to the Company or an Affiliate
as a Consultant or Director after your employment terminates or if you otherwise
exercise your option more than three (3) months after the date your employment
terminates.



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        8. EXERCISE.

           (a) You may exercise the vested portion of your option (and the
unvested portion of your option if your Grant Notice so permits) during its term
by delivering a Notice of Exercise (in a form designated by the Company)
together with the exercise price to the Secretary of the Company, or to such
other person as the Company may designate, during regular business hours,
together with such additional documents as the Company may then require.

           (b) By exercising your option you agree that, as a condition to any
exercise of your option, the Company may require you to enter into an
arrangement providing for the payment by you to the Company of any tax
withholding obligation of the Company arising by reason of (1) the exercise of
your option, (2) the lapse of any substantial risk of forfeiture to which the
shares of Common Stock are subject at the time of exercise, or (3) the
disposition of shares of Common Stock acquired upon such exercise.

           (c) If your option is an incentive stock option, by exercising your
option you agree that you will notify the Company in writing within fifteen (15)
days after the date of any disposition of any of the shares of the Common Stock
issued upon exercise of your option that occurs within two (2) years after the
date of your option grant or within one (1) year after such shares of Common
Stock are transferred upon exercise of your option.

           (d) By exercising your option you agree that the Company (or a
representative of the underwriter(s)) may, in connection with the first
underwritten registration of the offering of any securities of the Company under
the Securities Act, require that you not sell, dispose of, transfer, make any
short sale of, grant any option for the purchase of, or enter into any hedging
or similar transaction with the same economic effect as a sale, any shares of
Common Stock or other securities of the Company held by you, for a period of
time specified by the underwriter(s) (not to exceed one hundred eighty (180)
days) following the effective date of the registration statement of the Company
filed under the Securities Act. You further agree to execute and deliver such
other agreements as may be reasonably requested by the Company and/or the
underwriter(s) that are consistent with the foregoing or that are necessary to
give further effect thereto. In order to enforce the foregoing covenant, the
Company may impose stop-transfer instructions with respect to your shares of
Common Stock until the end of such period.

        9. TRANSFERABILITY. Your option is not transferable, except by will or
by the laws of descent and distribution, and is exercisable during your life
only by you. Notwithstanding the foregoing, by delivering written notice to the
Company, in a form satisfactory to the Company, you may designate a third party
who, in the event of your death, shall thereafter be entitled to exercise your
option.

        10. RIGHT OF FIRST REFUSAL. Shares of Common Stock that you acquire upon
exercise of your option are subject to any right of first refusal that may be
described in the Company's bylaws in effect at such time the Company elects to
exercise its right. The Company's right of first refusal shall expire on the
Listing Date.



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        11. RIGHT OF REPURCHASE. To the extent provided in the Company's bylaws
as amended from time to time, the Company shall have the right to repurchase all
or any part of the shares of Common Stock you acquire pursuant to the exercise
of your option.

        12. OPTION NOT A SERVICE CONTRACT. Your option is not an employment or
service contract, and nothing in your option shall be deemed to create in any
way whatsoever any obligation on your part to continue in the employ of the
Company or an Affiliate, or of the Company or an Affiliate to continue your
employment. In addition, nothing in your option shall obligate the Company or an
Affiliate, their respective shareholders, Boards of Directors, Officers or
Employees to continue any relationship that you might have as a Director or
Consultant for the Company or an Affiliate.

        13. WITHHOLDING OBLIGATIONS.

           (a) At the time you exercise your option, in whole or in part, or at
any time thereafter as requested by the Company, you hereby authorize
withholding from payroll and any other amounts payable to you, and otherwise
agree to make adequate provision for (including by means of a "cashless
exercise" pursuant to a program developed under Regulation T as promulgated by
the Federal Reserve Board to the extent permitted by the Company), any sums
required to satisfy the federal, state, local and foreign tax withholding
obligations of the Company or an Affiliate, if any, which arise in connection
with your option.

           (b) Upon your request and subject to approval by the Company, in its
sole discretion, and compliance with any applicable conditions or restrictions
of law, the Company may withhold from fully vested shares of Common Stock
otherwise issuable to you upon the exercise of your option a number of whole
shares of Common Stock having a Fair Market Value, determined by the Company as
of the date of exercise, not in excess of the minimum amount of tax required to
be withheld by law. If the date of determination of any tax withholding
obligation is deferred to a date later than the date of exercise of your option,
share withholding pursuant to the preceding sentence shall not be permitted
unless you make a proper and timely election under Section 83(b) of the Code,
covering the aggregate number of shares of Common Stock acquired upon such
exercise with respect to which such determination is otherwise deferred, to
accelerate the determination of such tax withholding obligation to the date of
exercise of your option. Notwithstanding the filing of such election, shares of
Common Stock shall be withheld solely from fully vested shares of Common Stock
determined as of the date of exercise of your option that are otherwise issuable
to you upon such exercise. Any adverse consequences to you arising in connection
with such share withholding procedure shall be your sole responsibility.

           (c) You may not exercise your option unless the tax withholding
obligations of the Company and/or any Affiliate are satisfied. Accordingly, you
may not be able to exercise your option when desired even though your option is
vested, and the Company shall have no obligation to issue a certificate for such
shares of Common Stock or release such shares of Common Stock from any escrow
provided for herein.

        14. NOTICES. Any notices provided for in your option or the Plan shall
be given in writing and shall be deemed effectively given upon receipt or, in
the case of notices delivered by



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mail by the Company to you, five (5) days after deposit in the United States
mail, postage prepaid, addressed to you at the last address you provided to the
Company.

        15. GOVERNING PLAN DOCUMENT. Your option is subject to all the
provisions of the Plan, the provisions of which are hereby made a part of your
option, and is further subject to all interpretations, amendments, rules and
regulations which may from time to time be promulgated and adopted pursuant to
the Plan. In the event of any conflict between the provisions of your option and
those of the Plan, the provisions of the Plan shall control.


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