<PAGE>   1
                                                                   EXHIBIT 10.36



                                                               SIGNATURE VERSION



                                           *** Text Omitted and Filed Separately
                                          Confidential Treatment Requested Under
                             17 C.F.R. Sections 200.80(b)(4), 200.83 and 230.406




                     JOINT MARKETING AND PROMOTION AGREEMENT



                                    between:



                           HEALTHEON/WEBMD CORPORATION

                             a Delaware Corporation;



                                       and



                                MEDIBUY.COM, INC.

                             a Delaware Corporation


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

                          Dated as of January 18, 2000

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

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                                                               SIGNATURE VERSION

                                TABLE OF CONTENTS
--------------------------------------------------------------------------------

<TABLE>
<S>                                                                                 <C>
1. DEFINITIONS AND RULES OF CONSTRUCTION..............................................1
        1.01 General Definitions......................................................1
        1.02 Terms Defined in the Agreement...........................................3
        1.03 Rules of Construction....................................................3

2. NEW COMMERCE SITE DEVELOPMENT PLAN.................................................3

3. CREATION OF THE NEW COMMERCE SITE AND MODIFICATIONS TO EXISTING SITES..............4
        3.01 Changes to the MEDIBUY Site..............................................4
        3.02 Creation of the New Commerce Site........................................4
           (a) General................................................................4
           (b) Hosting................................................................4
           (c) Look and Feel..........................................................4
           (d) Access to the New Commerce Site........................................5
        3.03 Future Changes to the Look and Feel of the WebMD Professional Site.......5

4. PERFORMANCE STANDARDS..............................................................5
        4.01 Technical Performance Standards..........................................5
        4.02 Standards Relating to the New Commerce Site..............................6
           (a) General................................................................6
           (b) Record Keeping.........................................................6
           (c) Discounts..............................................................6

5. ADVERTISING AND PROMOTION..........................................................6
        5.01 Launch Campaign by WebMD.................................................6
        5.02 Post Launch Campaign by WebMD............................................7
        5.03 Sales Development Obligations of MEDIBUY.................................7

6. CHANGES TO PRODUCTS AND SERVICES OFFERED BY THE NEW COMMERCE SITE..................7
        6.01 Prohibited Uses..........................................................7
        6.02 Right of MEDIBUY to Provide New Vendors and Products.....................8
        6.03 Right of WebMD to Request that MEDIBUY Introduce New Vendors or Products.8
        6.04 Right of WebMD to Request that MEDIBUY Prevent the Offering of Certain
             Products or Services to WebMD Members....................................9
        6.05 Removal of Illicit and Harmful Items.....................................9

7. EXCLUSIVITY........................................................................9
        7.01 Definitions Related to Exclusivity.......................................9
        7.02 MEDIBUY's Exclusive Rights..............................................10
           (a) Promotion of Medibuy Competitors......................................10
           (b) Exceptions............................................................10
        7.03 When WebMD May Terminate MEDIBUY's Exclusive Rights.....................11
           (a) Failure to Implement the New Commerce Site Development Plan...........11
           (b) Failure to Meet Technical Performance Standards.......................11
</TABLE>



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                                                               SIGNATURE VERSION


<TABLE>
<S>                                                                                 <C>
           (c) Sale or Promotion of Certain Products.................................11
        7.04 WebMD's Exclusive Rights................................................11
        7.05 Sponsorship Arrangements................................................12
        7.06 When MEDIBUY May Terminate WebMD's Exclusive Rights.....................12
           (a) Failure to Implement the New Commerce Site Development Plan...........12
           (b) Sale or Promotion of Certain Products.................................13
        7.07 No Exclusive Rights as Regards Services.................................13

8. COMPENSATION......................................................................13
        8.01 General.................................................................13
        8.02 Payment and Reporting Terms.............................................14
        8.03 Audit Rights............................................................15
        8.04 Change in Law...........................................................15
        8.05 MEDIBUY Linking Option..................................................16

9. LICENSES..........................................................................16
        9.01 Reciprocal Right to Use Marks...........................................16
        9.02 RESTRICTIONS ON USE OF MARKS............................................16

10. GOVERNANCE AND OVERSIGHT.........................................................17
        10.01 Appointment and Role Contract Managers.................................17
        10.02 Appointment and Role Steering Group....................................17

11. DISPUTE RESOLUTION...............................................................18
        11.01 Efforts by Contract Managers...........................................18
        11.02 Efforts by Steering Committee..........................................18
        11.03 Mediation and Arbitration..............................................19

12. WEBMD MEMBER DATA................................................................19
        12.01 Ownership..............................................................19
        12.02 Use of WebMD Member Data...............................................19
        12.03 Security and Privacy...................................................20

13. OWNERSHIP OF INTELLECTUAL PROPERTY...............................................20
        13.01 Ownership by MEDIBUY...................................................20
        13.02 Ownership by WebMD.....................................................20
        13.03 Ownership and the New Commerce Site....................................20

14. TERM AND TERMINATION.............................................................21
        14.01 Term...................................................................21
        14.02 Early Termination by Either Party......................................21
           (a) Either Party..........................................................21
           (b) By MEDIBUY............................................................21
        14.03 Transition Planning....................................................22
        14.04 Effect of Termination..................................................22
        14.05 Survival...............................................................22

15. REPRESENTATIONS AND WARRANTIES...................................................22
</TABLE>



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                                                               SIGNATURE VERSION

<TABLE>
<S>                                                                                 <C>
        15.01 Mutual Representations and Warranties..................................22
        15.02 Representations and Warranties by WebMD................................23
        15.03 Representations and Warranties by MEDIBUY..............................23
        15.04 Indemnity..............................................................24
           (a) Each Party............................................................24
           (B) MEDIBUY...............................................................24
        15.05 Indemnification Procedure..............................................24
        15.06 Infringement Indemnity.................................................25
        15.07 No Other Representations or Warranties.................................25
        15.08 Remedies Cumulative....................................................25

16. DISCLAIMER OF OTHER WARRANTIES...................................................25

17. LIMITATION OF LIABILITY..........................................................26

18. CONFIDENTIALITY..................................................................26
        18.01 Confidential Information...............................................26
        18.02 Protection of Confidential Information.................................26
        18.03 Permitted Disclosure...................................................27
        18.04 Applicability..........................................................27
        18.05 Confidentiality of the Terms of this Agreement.........................27
        18.06 Public Disclosure of the Terms of this Agreement.......................27

19. MISCELLANEOUS....................................................................28
        19.01 Press Release..........................................................28
        19.02 No Joint Venture.......................................................28
        19.03 Governing Law..........................................................28
        19.04 Amendment or Modification..............................................28
        19.05 No Assignment..........................................................28
        19.06 Notices................................................................29
        19.07 Entire Agreement.......................................................30
        19.08 Waiver.................................................................30
        19.09 No Third Party Beneficiaries...........................................30
        19.10 Fees and Expenses......................................................30
        19.11 Severability...........................................................30
        19.12 Counterparts; Facsimiles...............................................31
        19.13 Insurance..............................................................31
</TABLE>



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                                                               SIGNATURE VERSION


                     JOINT MARKETING AND PROMOTION AGREEMENT

        This JOINT MARKETING AND PROMOTION AGREEMENT (the "Agreement"), by and
among HEALTHEON/WEBMD CORPORATION, a Delaware corporation, located at 4600
Patrick Henry Drive, Santa Clara, CA 95054, ("WebMD"), and MEDIBUY.COM, INC., a
Delaware corporation ("MEDIBUY "), is made and entered into as of the latest of
the signature dates set forth on the signature page below and shall be effective
as of such date (the "Effective Date").

                                    RECITALS

        A. WebMD owns and operates a Site on the world wide web currently titled
"WebMD" (the "WebMD Site") at and within the domain Webmd.com having a Home Page
(the "WebMD Home Page") that can be located by using the following universal
resource locator ("URL"), http://www.webmd.com/. The WebMD Site contains an
Action Link to subscription-based healthcare information and services for
healthcare professionals residing in the United States (the "WebMD Professional
Site") and an Action Link to the first, or "start" Page (the "WebMD Consumer
Start Page") of the portion of the WebMD Site which provides free healthcare
information services and online communities for consumers (the "WebMD Consumer
Site").

        B. MEDIBUY offers an Internet-based virtual marketplace to healthcare
professionals and vendors at http://www.medibuy.com ("MEDIBUY Site"). Healthcare
purchasing professionals use the transaction models and systems, including but
not limited to the eRFP, eAuction and eCatalog services, available at the
MEDIBUY Site as a quick, convenient way to electronically budget, source and
purchase medical and surgical products, commodity items, medical related
services capital equipment as well as business and facility-related products and
services. ("MEDIBUY Services").

        C. This Agreement sets out the terms and conditions pursuant to which
the Parties will provide certain services to each other, and compensate each
other for such services.

        NOW, THEREFORE, in consideration of the foregoing recitals (which by
this reference are hereby made a part of this Agreement) and the mutual promises
set forth herein, the parties hereby agree as follows:

                    1. DEFINITIONS AND RULES OF CONSTRUCTION.

1.01 GENERAL DEFINITIONS.

        For purposes of this Agreement, the following terms have the following
specified meanings:

        "ABOVE THE FOLD" means the portion of a Page that is designed to be
visible on a standard computer screen set to a resolution of 800 pixels by 600
pixels without requiring the User to scroll horizontally or vertically through
the Page.



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                                                               SIGNATURE VERSION

        "ACTION LINK" means a hypertext link, whether contained in a navigation
bar of a Site, an On-Line Ad, a button, tab, other graphical image or other
location on a Site, that, when clicked on by a User, takes the User to a
different Page in a Site or to a Page located on a different Site.

        "AFFILIATE" means, with respect to a Party, any Person that, directly or
indirectly, Controls, or is Controlled by, or is under common Control with, such
Party. For the purpose of this defined term, "Controls, Controlled by, or under
common Control with, means the possession, directly or indirectly, of the power
to direct or cause the direction of the management and policies of a Person,
whether by contract or through the ownership of voting securities, including the
ownership of more than fifty percent (50%) of the equity, partnership,
membership or similar interest in such Person.

        "GOVERNMENTAL BODY" means any federal, state, local, municipal, foreign,
or other government or quasi-governmental authority of any nature (including,
without limitation, any governmental agency, bureau, board, commission, branch,
department, entity, or other instrumentality, and any court or other tribunal).

        "CHANGE IN CONTROL" means any change in the actual or beneficial
ownership of more than forty percent (40%) of its voting stock in one or more
related transaction(s), forty percent (40%) or more of such voting stock is held
or controlled by any Third Party.

        "HOME PAGE" means the first page seen by a User when the User visits a
Site on the Internet.

        "INTERNET" means a global network of interconnected computer networks,
each using the Transmission Control Protocol/Internet Protocol and/or such other
standard network interconnection protocols as may be adopted from time to time,
which is used (among other things) to transmit content between, or enable
commercial transactions between, a Site and a User.

        "IP RIGHT" means any copyright, trademark, patent, trade secret, moral
right or other intellectual property or proprietary right of any kind (including
applications therefor and, in the case of patents, any continuation or
divisional patent applications claiming priority thereto), whether arising under
the laws of the United States or any other nation, state or jurisdiction
(including any foreign equivalents thereto).

        "LAW" shall mean any code, law (including common law), ordinance,
regulation, rule, or statute applicable to a Person or its business, including
those promulgated, interpreted or enforced by any Governmental Body.

        "LOOK AND FEEL" means, with respect to a Site, those elements of the
Graphical User Interface of such Site comprising the visible features,
characteristics and style of such Site which are unique to such Site and are
consistent from page to page and which indicate the common identity of the
various pages and identify such pages as forming a part of a single Site
operated by a specific Person.



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                                                               SIGNATURE VERSION

        "PAGE" means a screen of information, including text or graphics, that
is displayed on a User's computer screen when that User accesses a Site on the
Internet.

        "PARTY" means a party to this Agreement.

        "PERSON" means any individual, corporation, partnership, limited
liability company, trust, association or other entity or organization, including
any governmental or political subdivision or any agency or instrumentality
thereof.

        "SITE" means a Home Page and the Pages associated with such Home Page as
a unified Site that are accessible through the use of the Internet at a single
URL.

        "THIRD PARTY" means any Person that is not a Party or a wholly owned
Affiliate of a Party.

        "USER" means a user of the Internet.

        "VENDOR" means a vendor approved by MEDIBUY to participate in
transactions on the New Commerce Site as a provider of products.

        "WEBMD MEMBER" means any User who is a then current subscriber to the
WebMD Professional Site developed and offered for access and use by Users
residing in the United States of America.

1.02 TERMS DEFINED IN THE AGREEMENT.

        An index of terms defined in the body of the Agreement is attached
hereto as Exhibit 1.02.

1.03 RULES OF CONSTRUCTION.

        In this Agreement, unless the context requires otherwise, the singular
shall include the plural and vice versa. The words "including," "includes" or
"included," shall be deemed to be followed by the words "without limitation."

                     2. NEW COMMERCE SITE DEVELOPMENT PLAN.

        Within sixty (60) days following the Execution Date the Parties will use
their best efforts to jointly complete a project plan (the "New Commerce Site
Development Plan") that will set mutually agreeable deadlines for the various
tasks contemplated by this Agreement, including the design, rollout and
implementation of the New Commerce Site, and that sets forth mutually developed
guidelines, processes, procedures and plans for sales and marketing
communications and a mechanism for evaluating and jointly pursuing additional
service opportunities, to the extent such tasks, guidelines, processes,
procedures, plans and mechanisms are not otherwise provided or defined in this
Agreement.



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                                                               SIGNATURE VERSION

    3. CREATION OF THE NEW COMMERCE SITE AND MODIFICATIONS TO EXISTING SITES.

3.01 CHANGES TO THE MEDIBUY SITE.

        In accordance with the New Commerce Site Development Plan, MEDIBUY will
modify the "Buyer's Center" page of the MEDIBUY Site to include a section equal
in prominence to the "eRFP Manager" and "eAuction Manager" sections and Above
the Fold entitled "Buying for Physician Offices," which shall be an Action Link
leading to a page describing the New Commerce Site through WebMD as the
exclusive channel through which Physician Buyers may access MEDIBUY Services.

3.02 CREATION OF THE NEW COMMERCE SITE.

        (a) General

        In accordance with the New Commerce Site Development Plan MEDIBUY will
create a new Site (the "New Commerce Site") which: (i) will be hosted by MEDIBUY
on its servers and will be served within a frame served by WebMD as set forth in
the New Commerce Site Development Plan; (ii) will be accessible to WebMD Members
that click on Action Links located on the WebMD Professional Site which are
linked to a transition page on the New Commerce Site (each a "Transition Page");
(iii) will have the Look and Feel of the WebMD Professional Site, including the
navigation bar and other graphics that are generally present when a User visits
the various Pages of the WebMD Professional Site; and (iv) will allow a User to
use the MEDIBUY Services; all in accordance with the following subsections. The
Parties may mutually agree during the Term to have MEDIBUY serve the New
Commerce Site without a WebMD served frame.

        (b) Hosting

        The New Commerce Site will be hosted by MEDIBUY on its servers (or the
servers of its contractors) at MEDIBUY's sole cost and expense. The URL of the
New Commerce Site will be masked to MEDIBUY's Site by a URL such as
http://medibuy.webmd.com, and any such URL will be owned by WEBMD. If the
Parties agree that the New Commerce Site will be served completely by MEDIBUY
without a WebMD frame, the URL of the New Commerce Site will be a URL such as
http://webmd.medibuy.com and such URL shall be owned by MEDIBUY. WebMD will
receive Page view and reach credit for all User visits to each Transition Page
(which shall constitute the initial page of the New Commerce Site) and MEDIBUY
shall receive Page view and reach credit for all visits to all other pages of
the New Commerce Site. To the extent WebMD serves content to a page of the New
Commerce Site, and the served content constitutes a substantial portion of that
page, then WebMD shall receive Page view and reach credit for all User visits to
that page.

        (c) Look and Feel

        WebMD shall approve the Look and Feel of the New Commerce Site in its
reasonable discretion. The primary design goal is to preserve as much of the
then current Look and Feel of the WebMD Professional Site as reasonably possible
given the



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                                                               SIGNATURE VERSION

functions which will be available from the New Commerce Site, so that a WebMD
Member who views such Pages will feel that the WebMD Member remains on the WebMD
Professional Site but is experiencing services offered by MEDIBUY. Accordingly,
MEDIBUY will have branding on the New Commerce Site subservient to that of
WebMD, such as "Powered by medibuy.com" at a size smaller than and placement
less prominent than of WebMD branding. On-line Ads will not be placed on the New
Commerce Site. If the Parties agree that the New Commerce Site will be served
completely by MEDIBUY without a WebMD frame, the New Commerce Site will have a
copy of the navigation bar of the WebMD Professional Site (and its Action Links)
so that the WebMD Member can quickly return to the other Pages of the WebMD
Professional Site. WebMD shall design and place Action Links on the WebMD
Professional Site that link to the New Commerce Site, including placement on the
WebMD Professional Site navigation bar at no lower than its second level, thus
allowing a User to access a Transition Page with no more than two Action Link
activations. Each Party will bear its own costs incurred in connection with the
design of the New Commerce Site and the placement of such Action Links.

        (d) Access to the New Commerce Site.

        Access to the New Commerce Site shall be restricted to WebMD Members.
WebMD Members and all Physician Buyers must access the New Commerce Site through
Action Links on the WebMD Professional Site.

3.03 FUTURE CHANGES TO THE LOOK AND FEEL OF THE WEBMD PROFESSIONAL SITE.

        If, after the Effective Date, WebMD wishes to materially alter the Look
and Feel or the design elements of the WebMD Professional Site, then WebMD (i)
will give thirty (30) days advance notice of the "go live" date for such
changes; (ii) will confer with MEDIBUY regarding such changes and cooperate with
MEDIBUY in approving design changes to the New Commerce Site necessitated by the
alterations to the WebMD Professional Site; and (iii) take such other action as
may be commercially reasonable to carry out a coordinated design change. MEDIBUY
shall make and implement such design changes to the New Commerce Site on the "go
live" date for changes by WebMD to the WebMD Professional Site. MEDIBUY will
bear the reasonable costs of any changes required to be made to the Look and
Feel hereunder to the New Commerce Site.

                            4. PERFORMANCE STANDARDS.

4.01 TECHNICAL PERFORMANCE STANDARDS.

        The New Commerce Site will perform at or above the Technical Performance
Standards, a copy of which is attached as Exhibit 4.01.



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                                                               SIGNATURE VERSION

4.02 STANDARDS RELATING TO THE NEW COMMERCE SITE.

        (a) General

        MEDIBUY covenants that (except as prohibited by applicable Law ) Vendors
at the New Commerce Site will provide WebMD Members with online order
fulfillment for the products and services each offers through the MEDIBUY
Services, including the order fulfillment and credit card processing. MEDIBUY
shall use reasonable commercial efforts to establish a survey program to collect
information from Vendors describing the type, level and quality of customer
service functions provided by the Vendor (e.g. problem resolution, technical or
help desk support, warranty support, and returns and allowances) related to the
sale and delivery of products and services to WebMD Members through the New
Commerce Site and to make such customer service information conspicuously
available to WebMD Members at the New Commerce Site. The New Commerce Site shall
be fully functional seven (7) days per week, twenty-four (24) hours per day,
subject only to planned and unplanned downtime as permitted by the Technical
Standards. MEDIBUY will perform all its services hereunder in a manner that is
consistent with commercially acceptable standards of quality and customer
service applicable to first class on-line marketplace providers and in
accordance with the New Commerce Site Development Plan.

        (b) Record Keeping

        MEDIBUY shall be responsible for keeping all records with respect to
products sold through the New Commerce Site as may be necessary or reasonably
desirable in order to (i) comply with applicable Law; and (ii) to verify the
service fees due WebMD under this Agreement. Such records shall be maintained so
as to reasonably satisfy any potential audit by any Governmental Body having
jurisdiction over MEDIBUY or by any payor which has paid for items purchased
through the New Commerce Site. Such records shall be subject to audit by WebMD's
representatives pursuant to Section 1.01 during the Term and for one (1) year
thereafter.

        (c) Discounts

        MEDIBUY shall use its commercially reasonable efforts to establish for
WebMD Members pricing levels from Vendors for products and services offered by
the Vendors at the New Commerce Site at a discount to retail pricing competitive
with discounts provided by MEDIBUY Competitors.

                          5. ADVERTISING AND PROMOTION.

5.01 LAUNCH CAMPAIGN BY WEBMD.

        WebMD shall deploy a launch campaign for the New Commerce Site between
March 1, 2000 and May 31, 2000. By February 15, 2000, WebMD shall present
MEDIBUY the detailed plan for the launch campaign, outlining such elements as
online promotion, placement on the WebMD Professional Site, rewards and
incentive programs, banner ads on lab reports, direct mail campaign, collateral
for physician services used at



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<PAGE>   11
                                                               SIGNATURE VERSION

tradeshows/exhibits, training programs for WebMD Members and development of
internal sales plans.

5.02 POST LAUNCH CAMPAIGN BY WebMD.

        WebMD shall deploy on-going advertising for the New Commerce Site after
the launch campaign during the Term. By June 15, 2000, WebMD shall present
MEDIBUY a detailed plan for its post launch campaign, outlining such elements as
online promotion, placement on the WebMD Professional Site, rewards and
incentive programs, banner ads on lab reports, direct mail campaigns, collateral
for physician services used at tradeshows/exhibits, training programs for WebMD
Members and development of internal sales plans.

5.03 SALES DEVELOPMENT OBLIGATIONS OF MEDIBUY.

        MEDIBUY shall deploy advertising for the WebMD Site and the New Commerce
Site to its customers during the Term. By February 15, 2000, MEDIBUY shall
present WEBMD a detailed plan for its post launch campaign to develop increased
sales through the New Commerce Site, outlining such elements as online
promotions, providing and promoting the capability to access through the New
Commerce Site products and services from multiple distributors, manufacturers
and providers; providing and promoting the availability of multiple pricing
schemes based on a WebMD Member's affiliations including that with WebMD;
providing and promoting real time purchasing processes; and development of
internal sales plans.

        Any online promotions of the New Commerce Site by MEDIBUY shall be under
terms mutually agreed to by the Parties.

      6. CHANGES TO PRODUCTS AND SERVICES OFFERED BY THE NEW COMMERCE SITE.

6.01 PROHIBITED USES

        MEDIBUY warrants it prohibits Vendors from using the MEDIBUY Services
for anything other than a lawful and legitimate business purpose. Examples of
other than lawful and legitimate business uses by Vendors of the MEDIBUY
Services, but are not limited to, the following: (i) selling or offering (x)
stolen property, counterfeit items, contraband, controlled substances, firearms;
tobacco; pornography, (y) products or services that violate any state or federal
statute or regulation regarding the display, promotion, advertising,
recommending or sale of medical supplies, (z) products or services or any other
material which it is unlawful for the Vendor to sell or a WebMD Member to
acquire (subsections (x)-(z) cumulatively the "Illicit Items"); (ii) placement
on the New Commerce Site of any untrue, malicious, fraudulent, harassing,
offensive or defamatory material, or any material that is irrelevant to a
legitimate use of the site; (iii) introduction of viruses, worms or other
programming routines that are intended to disrupt or interfere with the intended
operation of the site; (iv) insertion of links to other sites of whatever
character; (v) promotion of any unlawful activity or purpose, including any
activity that could give rise to criminal or civil liability; (vi) manipulation
of pricing on transactions by any means, including the placement of bad faith
bids, use of shills in the



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<PAGE>   12
                                                               SIGNATURE VERSION

auction process or collusion between a buyer and seller to cause harm to a
competitor; (vii) unauthorized alteration of any data or information supplied by
another user of the site: or (viii) any activity that infringes on the
copyright, patent, trademark or other rights of any person or entity.


6.02 RIGHT OF MEDIBUY TO PROVIDE NEW VENDORS AND PRODUCTS.

        From time to time during the Term, MEDIBUY shall be entitled to
introduce new or replacement (i) Vendors who offer new or replacement products
or services for sale through the New Commerce Site, and (ii) MEDIBUY Services,
provided however, that MEDIBUY may not introduce Vendors who or services
prohibited by Section 6.01.

6.03 RIGHT OF WebMD TO REQUEST THAT MEDIBUY INTRODUCE NEW VENDORS OR PRODUCTS.

        If WebMD reasonably believes that WebMD Members would purchase on-line
significant quantities of any specific medical, surgical or office products or
categories of products, WebMD will give MEDIBUY a written notice (the "New
Product Notice") specifying the name and manufacturer or Vendor of the products
or categories and a description thereof and the pricing of same (the "New
Products") or the identity of a company that offers such products or categories
for sale on-line (the "Additional Commerce Partner").

        If within ten (10) days of such notice MEDIBUY shall not have given
WebMD written notice of MEDIBUY's intent to introduce Vendors who shall, or the
agreement of current Vendors to offer such New Products, or products that are
substantially similar to the New Products (the "Substitute Product"), as
applicable, on the New Commerce Site within ninety (90) days, then,
notwithstanding any other provisions of this Agreement, WebMD may sell,
distribute or promote the New Products on the WebMD Professional Site or through
the use of an Action Link on the WebMD Professional Site to the Site of a Third
Party or otherwise; or enter into an alliance agreement with such Additional
Commerce Partner pursuant to which WebMD may promote and pursuant to which WebMD
Members can access the on-line offerings of such Additional Commerce Partner, as
applicable for the New Products only.

        Furthermore, if within one hundred (100) days of the New Product Notice
the New Commerce Site shall not have begun to offer through Vendors the New
Products or the Substitute Products, WebMD may sell, distribute or promote the
New Products on the WebMD Professional Site or through the use of an Action Link
on the WebMD Professional Site to the Site of a Third Party or otherwise; or
enter into an alliance agreement with such Additional Commerce Partner pursuant
to which WebMD may promote and pursuant to which WebMD Members can access the
on-line offerings of such Additional Commerce Partner, as applicable for the New
Products only.



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                                                               SIGNATURE VERSION

6.04 RIGHT OF WebMD TO REQUEST THAT MEDIBUY PREVENT THE OFFERING OF CERTAIN
PRODUCTS OR SERVICES TO WebMD MEMBERS.

        If WebMD reasonably believes that the offering for sale of any product
or service through the New Commerce Site may harm or cause injury to third
parties, or harm the reputation or goodwill of WebMD, or is competitive to
services then offered by WebMD (the "Harmful Items"), MEDIBUY shall not offer,
and shall prevent Vendors from offering, the product or service through the New
Commerce Site following the procedure of Section 6.05.

6.05 REMOVAL OF ILLICIT AND HARMFUL ITEMS.

        If (i) MEDIBUY should reasonably know or (ii) MEDIBUY is notified by
WebMD or a Third Party that a Vendor is offering through the New Commerce Site
any Illicit or Harmful Item then MEDIBUY shall use its best efforts to remove
the Illicit or Harmful Item from being offered on the New Commerce Site within
seventy-two (72) hours of MEDIBUY reasonably knowing or being notified of any
Illicit or Harmful Item on the New Commerce Site (the "Removal Period"). Such
best efforts may include (i) instructing and having the Vendor remove the
Illicit or Harmful Item from the New Commerce Site, (ii) MEDIBUY removing the
Illicit or Harmful Item from the New Commerce Site or (iii) preventing the
Vendor from participating in the New Commerce Site until the Illicit or Harmful
Item is removed from the Vendor's offerings on the new Commerce Site. MEDIBUY
shall promptly notify WebMD of all communications between and actions taken by
MEDIBUY and a Vendor concerning any Illicit or Harmful Item during the Removal
Period and thereafter until the Illicit or Harmful Item is removed from the New
Commerce Site.

                                 7. EXCLUSIVITY.

7.01 DEFINITIONS RELATED TO EXCLUSIVITY.

        "MEDIBUY COMPETITOR" means a Third Party or Affiliate of a Third Party
having a principal business of providing an on-line marketplace for the sale or
on-line sales of medical, surgical and general office supplies directly to
private practice physicians, out-patient clinics, IDNs, acute care or extended
care facilities; provided however, that notwithstanding the foregoing, the term
MEDIBUY Competitor shall not include (i) E.I. Du Pont De Nemours & Co., or (ii)
any other entity mutually agreed upon by the parties; provided, however that
MEDIBUY agrees to act promptly and reasonably if WebMD requests that additional
entities be added to the foregoing list to determine if it will allow the
amendment, or (iii) any Additional Commerce Partner permitted by Section 6.02
with respect to the sale of New Products only.

        "WebMD COMPETITOR" means a Third Party or an Affiliate thereof
principally engaged in the business of providing on-line healthcare information
and services to private practice physicians, out-patient clinics, IDNs, acute
care or extended care facilities or consumers or online health related
communities for consumers, and shall include drkoop.com, CareInsite,
IntelliHealth and Medscape.



9
<PAGE>   14
                                                               SIGNATURE VERSION

        "PHYSICIAN BUYER" When establishing a buyer's account for the MEDIBUY
Services, each User shall identify itself as purchasing products and services
for (i) an acute care facility, (ii) an extended care facility, (iii) a private
practice physician/physician group or (iv) an out-patient clinic. "Physician
Buyer" shall mean all user who identify themselves under the procedure above as
buying for a private practice physician/physician group or an out-patient
clinic.

7.02 MEDIBUY'S EXCLUSIVE RIGHTS.

        (a) Promotion of Medibuy Competitors

        Except as otherwise provided herein and except for WebMD's obligations
to (i) McKesson/HBOC Inc. under that certain agreement dated September 1, 1999
as existing as of the Effective Date, and (ii) Neoforma.com Inc. under that
certain agreement dated May 12, 1999 as existing as of the Effective Date,
during the Term, WebMD will not (i) place an Action Link to, or an On-Line
Advertisement or any other advertisement or promotion for, a MEDIBUY Competitor
on any Page of the WebMD Professional Site or any frame to the New Commerce Site
served by WebMD; (ii) otherwise advertise, promote or facilitate, directly or
indirectly, to a WebMD Member or any Person qualified to become a WebMD Member
access to or use of any on-line commerce Site of a MEDIBUY Competitor for the
procurement of medical, surgical or general office supplies, whether in off-line
media, or in any communication made by or on behalf of WebMD, including e-mail,
direct mail, or advertising sent or communicated by WebMD to WebMD Members or
any Person qualified to become a WebMD Member in any manner or (iii) offer
services which are substantially similar to any MEDIBUY Service for the
procurement of any medical, surgical or general office supplies; provided
however, notwithstanding the foregoing, WebMD may advertise to WebMD Members any
medical, surgical or general office supplies product produced or manufactured,
or medical, business and facility-related services provided, by or on behalf of,
any Third Party manufacturer or provider (collectively, the "MEDIBUY Exclusive
Rights").

        (b) Exceptions

        Notwithstanding the foregoing Section 7.02(a), if a WebMD Member
requires access to a designated Group Purchasing Organization ("GPO") for its
purchasing needs, WebMD shall have the right to (i) customize the WebMD
Professional Site for any such WebMD Member such that the WebMD Member has
access to any GPO(s)the WebMD Member is a member of through the customized WebMD
Professional Site and (ii) create co-branded or non-WebMD branded versions of
the WebMD Professional Site for use by an IDN, acute care center or extended
care center (collectively "Institution") limiting purchasing services access to
only those purchasing services offered by the designated GPO(s) for that
Institution (each an "Institution Channel").

        WebMD shall notify MEDIBUY of negotiations to establish an Institution
Channel. MEDIBUY shall have until thirty (30) days after such notice to offer a
solution that will satisfy the needs of the Institution Channel to provide
Institution members the ability to purchase the products and services offered by
a designated GPO(s) to Institution



10
<PAGE>   15
                                                               SIGNATURE VERSION

members through the Institution Channel as integrated with the New Commerce
Site. The needs of the Institution Channel may require MEDIBUY to customize the
New Commerce Site as viewed by Institution members, including limiting Vendors
available to designated GPO(s), limiting products and services offered or
presenting Institution member specific pricing. If the Institution rejects the
MEDIBUY solution or does not respond to the solution offered by MEDIBUY within
ten (10) days, WebMD shall offer access to the designated GPO(s) solely by
launching a new browser window in which will appear content solely served by
that GPO. WebMD shall not, other than as set forth in this paragraph, advertise,
promote or facilitate, directly or indirectly, to a WebMD Member or any Person
qualified to become a WebMD Member access to or use of the Site of a designated
GPO(s) for the procurement of medical, surgical or general office supplies.

7.03 WHEN WebMD MAY TERMINATE MEDIBUY'S EXCLUSIVE RIGHTS.

        (a) Failure to Implement the New Commerce Site Development Plan

        If, at any time during the term of this Agreement, MEDIBUY fails to (i)
implement or (ii) work in good faith with WebMD in the development of the New
Commerce Site Development Plan, then WebMD may, on thirty (30) days advance
written notice and opportunity to cure to MEDIBUY, terminate the MEDIBUY
Exclusive Rights.

        (b) Failure to Meet Technical Performance Standards.

        If, at any time during the term of this Agreement, MEDIBUY fails to meet
the Technical Performance Standards, then WebMD may, on thirty (30) days advance
written notice to and opportunity to cure for MEDIBUY, terminate the MEDIBUY
Exclusive Rights. Additionally, if at any time during the term of this
Agreement, MEDIBUY fails to meet the Technical Performance Standards for three
(3) consecutive months or three (3) out of twelve (12) consecutive months shall
give WebMD the right to terminate the Exclusive Rights of MEDIBUY.

        (c) Sale or Promotion of Certain Products.

        If, at any time during the Term of this Agreement, the MEDIBUY Services,
either through the action or omission of MEDIBUY or a Vendor breaches the
prohibitions regarding the sale or promotion of products or services that
violate any state or federal statute or regulation regarding the display,
promotion, advertising, recommending or sale of medical supplies, or products or
services or any other material which it is unlawful for the Vendor to sell or a
WebMD Member to acquire under Section 6.01, or fails to remove Harmful Items
under Section 6.04 then WebMD may, on thirty (30) days advance written notice to
and opportunity to cure for MEDIBUY, terminate the MEDIBUY Exclusive Rights.

7.04 WebMD'S EXCLUSIVE RIGHTS.

        Except as otherwise provided herein and except as to MEDIBUY's
obligations to Physiciansite.com, Inc in that certain agreement last dated
November 3, 1999, during the Term, MEDIBUY will not (i) place an Action Link to,
or an On-Line Advertisement or any



11
<PAGE>   16
                                                               SIGNATURE VERSION

other advertisement or promotion for, a WebMD Competitor on any Page of the New
Commerce Site or MEDIBUY Site; (ii) otherwise advertise or promote a WebMD
Competitor, whether in off-line media or in on-line media, or in any
communication made by or on behalf of MEDIBUY, including, e-mail, direct mail,
or advertising sent or communicated by MEDIBUY to its Vendors and buyers in any
manner; (iii) offer health related content on, or by use of any Action Link on,
the New Commerce Site, except (x) content concerning trends and statistical
analysis relating to purchasing medical and surgical products, commodity items,
medical related services capital equipment as well as business and
facility-related products and services (y) health related content provided by
WebMD or manufacturers, distributors or sellers of, and directly relating to
products or services offered through the New Commerce Site or the MEDIBUY Site
or with respect to the MEDIBUY Site only, other health related content that is
not otherwise provided by WebMD which may be offered by MEDIBUY in accordance
with the following paragraph or (z) generally and widely published and
distributed journalistic articles or reports principally discussing e-commerce
as it relates to the healthcare supply industry or the healthcare supply chain,
or (iv) offer the MEDIBUY Services to any Physician Buyer other than through the
WebMD Professional Site (collectively, the "WebMD Exclusive Rights").

        In the event MEDIBUY proposes to offer health related content provided
by a Third Party (which Third Party shall in no event include any integrated
provider of on-line healthcare information services whose principal business is
competitive with WebMD's principal business, including, for example, drkoop.com,
CareInsite, IntelliHealth and Medscape) on the MEDIBUY Site which content is not
then provided by WebMD, MEDIBUY shall notify WebMD of its desire to offer such
content, describing in its notice the nature of the desired content. WebMD shall
have until thirty (30) days after MEDIBUY'S notice to provide the content as
described in MEDIBUY'S notice. If WebMD rejects the opportunity to provide the
content or fails to provide such content within the 30 day period, then MEDIBUY
shall have the right to offer the Third Party content on the New Commerce Site
and/or the MEDIBUY Site.

7.05 SPONSORSHIP ARRANGEMENTS.

        Nothing in this Agreement precludes WebMD or MEDIBUY from co-sponsoring
or co-endorsing any event, service or product also co-sponsored or co-endorsed
by a MEDIBUY Competitor or WebMD Competitor.

7.06 WHEN MEDIBUY MAY TERMINATE WebMD'S EXCLUSIVE RIGHTS.

        (a) Failure to Implement the New Commerce Site Development Plan

        If, at any time during the term of this Agreement, WebMD fails to work
in good faith with MEDIBUY in the development of the New Commerce Site
Development Plan, then MEDIBUY may, on thirty (30) days advance written notice
and opportunity to cure to WebMD, terminate the WebMD Exclusive Rights.



12
<PAGE>   17
                                                               SIGNATURE VERSION

        (b) Sale or Promotion of Certain Products.

        If, at any time during the Term of this Agreement, either through its
action or omission, WebMD sells or promotes products or services, other than
through the New Commerce Site, that violate any state or federal statute or
regulation regarding the display, promotion, advertising, recommending or sale
of medical supplies then MEDIBUY may, on thirty (30) days advance written notice
to and opportunity to cure for WebMD, terminate the WebMD Exclusive Rights.

7.07 NO EXCLUSIVE RIGHTS AS REGARDS SERVICES

        Notwithstanding anything to the contrary herein, the Agreement does not
preclude WebMD from creating a hyperlink from the WebMD Professional Site to,
advertising, promoting or facilitating, directly or indirectly, to a WebMD
Member access to any page solely relating to medical, business and
facility-related services of an on-line commerce Site of a MEDIBUY Competitor;
provided such page does not advertise, promote or facilitate, directly or
indirectly, the sale of medical products, surgical products, or general office
supplies.

        If at any time during the Term WebMD notifies MEDIBUY it has entered
into an agreement precluding the New Commerce Site from offering WebMD Members a
specific service, MEDIBUY shall use commercially reasonable efforts to remove
the specific service from being offered on the New Commerce Site, but in no
instance more than thirty (30) days after such notice.

                                8. COMPENSATION.

8.01 GENERAL.

        (a) MEDIBUY will pay WebMD:

        (i) a Slotting Fee during each year of the Term for the services
delivered by and obligations of WebMD under Section 7.04 according to the
following chart


<TABLE>
<S>                                              <C>
                                 2000            $[...***...]
                                 2001            $[...***...]
                                 2002            $[...***...]
</TABLE>

        in equal quarterly payments on each January 1, April 1, July 1 and
October 1. In 2000 the January 1 and April 1 installments (aggregate
$[...***...]) shall be paid within fifteen (15) days of the Effective Date,
plus;

        (ii) for the services delivered by WebMD under Sections 5.01, 5.02
[...***...] of all Net Fees for transactions derived from the MEDIBUY Services
described as eAuction



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<PAGE>   18
                                                               SIGNATURE VERSION

and as further described in attached Schedule 8.01 by WebMD Members through the
New Commerce Site during the Term, plus;

        (iii) for the services delivered by WebMD under Sections 5.01, 5.02
[...***...] of all Net Fees for transactions derived from the MEDIBUY Services
described as eRFP and eCatalog (when available) and as further described in
attached Schedule 8.01 by WebMD Members through the New Commerce Site during the
Term; and

        (iv) a mutually determined percentage of all compensation derived from
each MEDIBUY Service available hereafter through the New Commerce Site.

        "Net Fees" means all compensation received by MEDIBUY attributable to
the use of the MEDIBUY Services by WebMD Members, excluding only those amounts
that MEDIBUY rebates to any WebMD Member, any credit card or other fees charges
to and payable by MEDIBUY as a result of the method of payment selected by the
WebMD Member, and any refund that MEDIBUY makes to any WebMD Member, which
amount would not have been included in Net Fees had it not been refunded.

        (b) WebMD will pay MEDIBUY a Sales Development Fee for the services
delivered by MEDIBUY under Article 4 and Section 5.03, as follows:


<TABLE>
<S>                                                 <C>
                                 2000               $[...***...]
                                 2001               $[...***...]
                                 2002               $[...***...]
</TABLE>

        in equal quarterly payments on each January 1, April 1, July 1, and
October 1 during the Term. The April 1, 2000 Sales Development Fee payment shall
be $[...***...]and payable March 31, 2000.

        (c) Neither Party shall be entitled to compensation from the other Party
except as set forth in this Article 8.

8.02 PAYMENT AND REPORTING TERMS.

        MEDIBUY will remit the designated percentage of Net Fees payable to
WebMD under Section 8.01 (a)(ii)-(i) within thirty (30) days following the end
of the month in which such fees were earned. MEDIBUY shall provide WebMD with a
report of the fees earned by WebMD at the time such fees are remitted to WebMD.
MEDIBUY also shall maintain records of all transactions subject to this Article,
which records shall be subject to audit by WebMD in accordance with Section
1.01.



14                                            * Confidential Treatment Requested
<PAGE>   19
                                                               SIGNATURE VERSION


8.03 AUDIT RIGHTS

        Each Party shall have the right to audit the other Party no more than
twice per twelve (12) month period, and only during reasonable business hours
and upon reasonable notice to the audited Party, to determine the accuracy of
Net Fees payable to WebMD, or to determine the other Party's compliance with
Section 7.03 or Section 7.06, provided such audit is limited in scope to those
materials of a Party relevant to determine the accuracy of payments made by
MEDIBUY. If WebMD discovers a shortfall in the amount of fees paid by MEDIBUY
for any period during the Term, MEDIBUY shall promptly remit the shortfall to
WebMD following receipt of notice of the shortfall from WebMD. In addition,
MEDIBUY shall pay for the cost of WebMD's audit or review in the event WebMD
discovers a shortfall equal to at least five percent (5%) of the total amount
originally paid by MEDIBUY. In the event of any dispute regarding the audit
determination of either Party, the disputing Party shall notify the other Party
of the nature of such dispute, the dispute will be referred to the Dispute
Resolution provisions of this Agreement set out at Article 11.

8.04 CHANGE IN LAW.

        The Parties agree that in the event after the Effective Date of this
Agreement there is a change in any applicable Law, which change would make
continued performance by either Party under this Agreement impossible,
intolerable, or in material violation of applicable Law, then, in such instance,
this Agreement shall be modified in writing by the Parties hereto in accordance
with the following procedures:

        To the extent that this Agreement fails to comply with any applicable
Law due to a change described by this Section 8.04, the Parties shall
immediately modify this Agreement, including this Section 10, within thirty (30)
days after the effective date of such change in order to comply with applicable
Law and to preserve the economic benefits contemplated by the Parties; and, if
the Parties cannot, after good faith negotiations, mutually agree within such
30-day period upon changes necessary to comply with such applicable Law, this
Agreement shall immediately terminate and be of no further force and effect.

        Further, upon the effective date of any such change in applicable Law,
either Party may request a suspension of both Parties' performance under this
Agreement until a modification under this Section 8.04 has been agreed to, and
upon such request the performance by both Parties will be suspended until the
Parties have agreed to such a modification, but any compensation earned by WebMD
pursuant to this Agreement prior to such a suspension will be paid when due. For
the purpose of this Section 8.04, the term "Law" shall include administrative
rulings, judicial decisions, manual provisions, fraud alerts prepared by the
Department of Health and Human Services' Office of the Inspector General ("OIG")
and Advisory Opinions Issued by the OIG.



15
<PAGE>   20
                                                               SIGNATURE VERSION

8.05 MEDIBUY LINKING OPTION

        In lieu of the agreements and obligations set forth in Articles 2-8,
MEDIBUY may elect to have WebMD provide a direct link to the MEDIBUY site on a
non-exclusive basis. Such link must be at least as prominent as that of any
other provider of medical products, surgical products or general office supplies
on the WebMD Site. In lieu of the compensation in Section 8.01, if MEDIBUY
elects this option, MEDIBUY shall pay a one time upfront fee of [...***...] for
allowing such access to the MEDIBUY Site from the WebMD Site.

                                  9. LICENSES.

9.01 RECIPROCAL RIGHT TO USE MARKS.

        Each Party hereby grants to each of the other Parties a world-wide,
royalty-free, non-exclusive license during the term to use all of such granting
Party's Marks set forth in Exhibit 9.01 hereto solely in connection with the
organization and operation of the New Commerce Site and the advertising,
marketing and promotion thereof and of products and services in each case in
accordance with the terms and conditions of this Agreement. Each party granting
a license to use Marks pursuant to the preceding sentence retains all right,
title and interest in and to the Marks provided by such Party, and does not
convey any proprietary interest therein to any other Party other than the
license rights specifically granted herein. Any use of a Party's Mark by the
other Party shall be pre-approved by the Party.

9.02 RESTRICTIONS ON USE OF MARKS.

        In addition to the other terms and conditions of this Agreement
pertaining to the use of the Marks, the use by each Party of any mark belonging
to any other Party (a "Co-Party Mark") shall be subject to the following terms
and conditions:

               i) Each Party expressly acknowledges that it shall not use any
        Co-Party Mark in any manner or for any purpose except as specifically
        permitted by this agreement.

               ii) Each Party acknowledges that each of the Co-Party Marks is
        widely known, is a trade name, trademark, service mark, logo and/or
        domain name owned by the Party to whom it is attributed hereunder (the
        "mark owner"), has obtained prestige and distinction as a designation
        for high quality products or services, has gained wide public acceptance
        and goodwill and is of great value and importance to the mark owner. the
        parties further acknowledge and agree that all use of the marks in
        connection with the new commerce site and the advertising, marketing and
        promotion thereof must preserve and protect the prestige and value of
        the marks and all rights of the respective mark owners therein and
        thereto.



16                                            * Confidential Treatment Requested
<PAGE>   21
                                                               SIGNATURE VERSION

               (iii) Each Party shall use the Co-Party Marks strictly in
        compliance with all applicable legal requirements. Each party shall
        cause to appear on all materials on or in connection with which any
        Co-Party Mark is used, such legends, markings and notices as may be
        reasonably necessary in order to give appropriate notice of any
        trademark or other rights therein or pertaining thereto.

               (iv) Each Party shall execute any documents reasonably required
        by a mark owner to confirm such mark owner's ownership of all rights in
        and to such mark owner's Co-Party Mark and the respective rights of the
        parties pursuant to this agreement.

               (v) No Party ever shall challenge the ownership of or the
        validity of a Co-Party Mark or any application for registration thereof,
        or any trademark registrations thereof, or any rights of the relevant
        mark owner therein. Also, no Party shall seek to register a Co-Party
        Mark or any variation or simulation thereof for any products or
        services, without the prior written consent of the mark owner.

               (vi) If any Party learns of any infringement or imitation of a
        Co-Party Mark, it promptly shall notify the relevant mark owner thereof.
        The relevant mark owner thereupon shall take such action as it deems
        advisable for the protection of its rights in and to such Co-Party Mark.
        No mark owner shall be required to take any action if it deems it
        inadvisable to do so and no other party may take any action with respect
        to a Co-Party Mark without the relevant mark owner's prior written
        approval.

               (vii) No Party has authorized any other Party hereunder to use
        its marks or any designation or identification relating to its marks or
        products in any manner or capacity other than as provided herein, except
        as may be set forth in a separate signed writing between such parties.

                          10. GOVERNANCE AND OVERSIGHT.

10.01 APPOINTMENT AND ROLE CONTRACT MANAGERS.

        Promptly following the Effective Date, each Party shall appoint an
individual who shall serve as such Party's primary representative for purposes
of this Agreement (each, a "Contract Manager"). Each Party may replace its
Contract Manager from time to time during the Term on Notice to the other Party.
Each Contract Manager shall have overall responsibility for managing and
coordinating the performance of its Party's obligations under this Agreement.

10.02 APPOINTMENT AND ROLE STEERING GROUP.

        Promptly following the Effective Date, the Parties will establish a
steering group, consisting of three executives from WebMD and three executives
from MEDIBUY. The steering group will meet on a regular basis, either in person
or via conference call, to set overall direction, monitor progress and resolve
issues regarding the affiliation created



17
<PAGE>   22
                                                               SIGNATURE VERSION

under this Agreement. The steering group will direct the Contract Managers to
implement the Agreement and roll-out of the affiliation seamlessly to all WebMD
Members.

                             11. DISPUTE RESOLUTION.

11.01 EFFORTS BY CONTRACT MANAGERS.

        Any dispute arising under this Agreement shall be considered first in
person or by telephone by Contract Managers within seven business days after
receipt (the date of receipt being referred to as the "Dispute Date") of a
Notice from either Party specifying the nature of the dispute and referencing
this Section. If for any reason, including a failure to meet or communicate, the
Contract Managers have not resolved such dispute to the satisfaction of the
Parties within twelve business days after the Dispute Date, then Contract
Managers shall immediately refer such dispute to the Steering Committee.

11.02 EFFORTS BY STEERING COMMITTEE.

        Each Steering Committee member shall make a good faith attempt to
consider such dispute in person or by telephone within twelve business days of a
dispute being referred to him or her. The Steering Committee shall meet as often
as the Parties reasonably deem necessary in order to gather and furnish to the
other all information with respect to the matter in issue which the Parties
believe to be appropriate and germane in connection with its resolution. The
Steering Committee shall discuss the problem and negotiate in good faith in an
effort to resolve the dispute without the necessity of any formal proceeding.
During the course of negotiations, all reasonable requests made by one Party to
another for non-privileged information, reasonably related to this Agreement,
will be honored in order that each of the Parties may be fully advised of the
other's position; provided, however, neither Party shall be required to disclose
its confidential or proprietary information. The specific format for the
discussions will be left to the discretion of the Steering Committee, but may
include the preparation of agreed-upon statements of fact or written statements
of position. The Parties agree that any such written statements will be prepared
in connection with settlement negotiations, and as such will be privileged and
shall not be used against the Party who prepared such statement unless it is
subsequently introduced by the preparing Party in formal proceedings.

        Should the Steering Committee fail to reach agreement within 30 days of
the initiation of the dispute resolution process (or such longer period as such
representatives may agree in writing), then formal proceedings for the
resolution of a dispute may be commenced in accordance with Section 11.03.

        The dispute resolution requirements set forth in this Article 11 shall
not apply to claims arising out of or related to: (a) any infringement or
misappropriation of either Party intellectual property, and (b) any violation of
the confidentiality obligations set forth in Article 18.



18
<PAGE>   23
                                                               SIGNATURE VERSION

11.03 MEDIATION AND ARBITRATION.

        The parties agree that any and all disputes, claims or controversies
arising out of or relating to this agreement that cannot be resolved pursuant to
Sections 11.01 or 11.02 shall be submitted to American Arbitration Association
(the "Arbitration Firm"), or its successor, for mediation, and if the matter is
not resolved through mediation, then it shall be submitted to the Arbitration
Firm, or its successor, for final and binding arbitration. Either Party may
commence mediation by providing to the Arbitration Firm and the other Party a
written request for mediation, setting forth the subject of the dispute and the
relief requested. The mediation will be conducted in accordance with the
Arbitration Firm's rules and procedures in effect at the time of filing of the
demand for arbitration. The parties will cooperate with the Arbitration Firm and
with one another in selecting a mediator from the Arbitration Firm's panel of
neutrals, and in scheduling the mediation proceedings. The parties covenant that
they will participate in the mediation in good faith, and that they will share
equally in its costs. All offers, promises, conduct and statements, whether oral
or written, made in the course of the mediation by any of the parties, their
agents, employees, experts and attorneys, and by the mediator or any employees
of the Arbitration Firm, are confidential, privileged and inadmissible for any
purpose, including impeachment, in any arbitration or other proceeding involving
the parties, provided that evidence that is otherwise admissible or discoverable
shall not be rendered inadmissible or non-discoverable as a result of its use in
the mediation. Either Party may initiate arbitration with respect to the matters
submitted to mediation by filing a written demand for arbitration at any time
following the initial mediation session or 45 days after the date of filing the
written request for mediation, whichever occurs first. The mediation may
continue after the commencement of arbitration if the parties so desire. Unless
otherwise agreed by the parties, the mediator shall be disqualified from serving
as arbitrator in the case. The provisions of this Section may be enforced by any
court of competent jurisdiction, and the Party seeking enforcement shall be
entitled to an award of all costs, fees and expenses, including attorneys fees,
to be paid by the Party against whom enforcement is ordered.

                             12. WebMD MEMBER DATA.

12.01 OWNERSHIP.

        WebMD shall own all data provided by a WebMD Member; whether collected
at the WebMD Site or the New Commerce Site (the "WebMD Member Data").

12.02 USE OF WebMD MEMBER DATA.

        MEDIBUY may only use WebMD Member Data to the extent necessary to
facilitate use of the MEDIBUY Services by the WebMD Member through the New
Commerce Site, and for no other purpose. WebMD may provide MEDIBUY such WebMD
Member Data, at WebMD's sole discretion. MEDIBUY may use for its own internal
purposes during the Term WebMD Member Data collected through the New Commerce
Site in a format that describes the habits, usage patterns, demographics, and/or
buying patterns of WebMD Members as a group but does not indicate the identity
of any



19
<PAGE>   24
                                                               SIGNATURE VERSION

particular WebMD Member, and information about an individual WebMD Member
presented in a form distinguishable from information relating to other WebMD
Members, but not in a form that enables a recipient to personally identify any
WebMD Member or locate or contact any WebMD Member ,even on an identity-blind
basis (the "Aggregate Information"). MEDIBUY shall make available to WebMD all
Aggregate Information in a format mutually agreed upon by the parties.

12.03 SECURITY AND PRIVACY.

        Subject to restrictions imposed under applicable Law, WebMD's then
current privacy policy will be the applicable privacy policy for the New
Commerce Site. MEDIBUY agrees not to accept submissions of information through
the New Commerce Site from individuals known to be nationals and residents of
the member states of the European Union.

                     13. OWNERSHIP OF INTELLECTUAL PROPERTY.

13.01 OWNERSHIP BY MEDIBUY.

        WebMD acknowledges that, as between it and MEDIBUY, MEDIBUY owns or is
the licensee of, all right, title and interest in and to all IP Rights contained
on the MEDIBUY Sites, including the MEDIBUY trademarks, except for any WebMD
trademarks displayed on such sites. WebMD understands and agrees that its use of
any of the foregoing MEDIBUY property in connection with this Agreement shall
not create in it any right, title or interest, in or to such property, and that
all such use and goodwill associated with any such use shall inure to the
benefit of MEDIBUY. MEDIBUY shall not develop during the Term or thereafter any
Site having a Look and Feel confusingly similar to that of the WebMD Site or the
New Commerce Site.

13.02 OWNERSHIP BY WebMD.

        MEDIBUY acknowledges that, as between it and WebMD, WebMD owns or is the
licensee of, all right, title and interest in and to all IP Rights contained on
the WebMD Sites, including the WebMD trademarks and the WebMD Content, except
for any MEDIBUY trademarks displayed on such sites. MEDIBUY understands and
agrees that its use of any of the foregoing WebMD property in connection with
this Agreement shall not create in it any right, title or interest, in or to
such property, and that all such use and goodwill associated with any such use
shall inure to the benefit of WebMD.

13.03 OWNERSHIP AND THE NEW COMMERCE SITE.

        Notwithstanding any statement to the contrary in this Agreement, MEDIBUY
acknowledges the Look and Feel of the New Commerce Site is the sole and
exclusive property of WebMD. WebMD acknowledges that any materials used on the
New Commerce Site developed solely by MEDIBUY without assistance from WebMD, as
between WebMD and MEDIBUY, shall be the sole exclusive property of MEDIBUY.
MEDIBUY acknowledges that any materials used on the New Commerce Site developed



20
<PAGE>   25
                                                               SIGNATURE VERSION

solely be WebMD without assistance from MEDIBUY, as between WebMD and MEDIBUY,
shall be the sole exclusive property of WebMD.

                            14. TERM AND TERMINATION.

14.01 TERM.

        This Agreement shall begin on the Effective Date, and shall expire April
1, 2003 (the "Term"), unless terminated earlier as provided below.

14.02 EARLY TERMINATION BY EITHER PARTY.

        "Material Breach" means a material uncured breach by a Party to meet its
obligations under this Agreement that (i) has a material adverse effect on the
other Party or (ii) is so egregious that the Agreement fails of its essential
purpose, unless the breaching Party cures such previously uncured failures
within sixty (60) days of receiving Notice thereof.

        (a) Either Party

        Either Party may terminate this Agreement upon written notice if

               (i) the other Party fails to make any payment due hereunder
               within 15 days of notice that a payment was not received when
               due;

               (ii) the other Party commits a Material Breach of this Agreement
               that is not cured within the time allowed by this Agreement,

               (iii) the other Party files a petition for bankruptcy or is
               adjudicated a bankrupt;

               (iv) a petition in bankruptcy is filed against the other Party
               and such petition is not dismissed within ninety (90) calendar
               days;

               (v) the other Party becomes insolvent or makes an assignment for
               the benefit of its creditors or an arrangement for its creditors
               pursuant to any bankruptcy law;

               (vi) a receiver is appointed for other Party or its business; or

        (b)    By MEDIBUY

               MEDIBUY may terminate this Agreement upon written notice if
               McKessonHBOC Inc. exercises its right to have WebMD continue to
               place an Action Link to any e-commerce Site designated by
               McKessonHBOC after November 12, 2000, which is the date one (1)
               year after the consummation of the transactions contemplated by
               the Healtheon-WebMD Reorganization Agreement.



21
<PAGE>   26
                                                               SIGNATURE VERSION

14.03 TRANSITION PLANNING.

        On April 1, 2002 the Parties may commence negotiations regarding the
renewal or extension of this Agreement, on such terms as the Parties may, in
their sole discretion, deem appropriate. If (i) either Party chooses not to
participate in such negotiations, (ii) either Party gives notice to the other
that it does not believe that the continuations of such negotiations are likely
to result in a renewed or extended agreement, or (iii) if the Parties have not
agreed to the essential terms on which this Agreement will be renewed or
extended by the date two years and six months after the Effective Date, then the
Parties will begin the negotiation of a Transition Plan. The Transition Plan
will set out the procedures that the Parties will follow during the Term to
inform visitors to their respective sites as to the location of the other
Parties' Site after the Term, and such other matters as the Parties may agree.

14.04 EFFECT OF TERMINATION.

        Termination of this Agreement by either Party shall not act as a waiver
of any breach of this Agreement and shall not act as a release of either Party
hereto from any liability for breach of such Party's obligations under this
Agreement.

        Within forty-five (45) calendar days following the expiration or
termination of this Agreement, each Party shall pay to the other Party all sums,
if any, due and owing as of the date of expiration or termination, net of any
amounts due from the other Party as of such date.

        Upon the termination of this Agreement each Party (i) will promptly
disable and remove any Action Links between such Party's sites (including Action
Links, if any, from Controlled Sites) and the New Commerce Site, as applicable;
(ii) shall promptly remove from such Party's sites all copies of all the other
Party's trademarks; (iii) shall promptly cease all other uses of the other
Party's trademarks and (iv) take such other actions as may be contained in the
Transition Plan.

14.05 SURVIVAL.

        Articles 11, 13, 15, 16, 17, and 18, and Sections 1.01, 14.04, 19.03,
and 19.11 shall survive expiration or termination of this Agreement.

                       15. REPRESENTATIONS AND WARRANTIES.

15.01 MUTUAL REPRESENTATIONS AND WARRANTIES.

        Each Party hereby represents and warrants to the other Party that:

        (a) It is a corporation duly organized, validly existing and in good
standing under the laws of the jurisdiction of its incorporation and has all the
necessary power and authority (i) to conduct its business in the manner in which
its business is currently being conducted, (ii) to own and use its assets in the
manner in which its assets are currently



22
<PAGE>   27
                                                               SIGNATURE VERSION

owned and used, and (iii) to enter into this Agreement and perform its
obligations under this Agreement; and

        (b) Its execution and delivery of this Agreement, and the performance of
its obligations and duties hereunder, do not and will not (i) conflict with or
result in any breach of any provision of its certificate of incorporation or
by-laws, (ii) require any filing with, or permit, authorization, consent or
approval of, any Governmental Body, (iii) result in a violation or breach of, or
constitute a default (or give rise to any right of termination, cancellation or
acceleration) under, any terms, conditions or provisions of any note, bond,
mortgage, indenture, lease, license, contract, agreement or other instrument or
obligation to which it is a party or by which any of its properties or assets
may be bound, (iv) violate any order, writ, injunction, decree, or Law
applicable to it, excluding from the foregoing clauses (ii), and (iii) such
filings, violations, breaches or defaults which would not, individually or in
the aggregate, have a material adverse effect on it or its ability to perform
under this Agreement.

15.02 REPRESENTATIONS AND WARRANTIES BY WebMD.

        WebMD represents and warrants that:

               a. The WebMD Site does not and will not contain any matter which
constitutes or results in a claim that, if true, constitutes libel, slander,
false light, invasion of privacy or any other tort against or with respect to
any Third Party;

               b. To the knowledge of WebMD, the WebMD Site, and the Look and
Feel of any frame to the New Commerce Site served by WebMD does not and will not
infringe the IP Rights of any Third Party; and

               c. The WebMD Professional Site, Look and Feel and any frame to
the New Commerce Site served by WebMD do not and will not violate applicable
Law.

15.03 REPRESENTATIONS AND WARRANTIES BY MEDIBUY.

        MEDIBUY represents and warrants that:

               a. The MEDIBUY Site and the New Commerce Site do not and will not
contain any matter which constitutes or results in a claim that, if true,
constitutes a libel slander, false light, invasion of privacy or any other tort
against or with respect to any Third Party;

               b. To the knowledge of MEDIBUY, the MEDIBUY Site and the New
Commerce Site do not and will not infringe the IP Rights of any Third Party;

               c. The MEDIBUY Site and the New Commerce Site do not and will not
violate applicable Law.



23
<PAGE>   28
                                                               SIGNATURE VERSION

15.04 INDEMNITY.

        (a) Each Party

        Each Party (the "Indemnifying Party") shall indemnify, defend and hold
the other Party harmless from and against all Losses incurred in connection with
or arising from any claim asserted by a Third Party that, if true, would
constitute a breach of a representation or warranty made by the Indemnifying
Party in Section 15.01, 15.02 or 15.03.

        (b) MEDIBUY

        MEDIBUY will indemnify, defend and hold WebMD harmless from any and all
loss, cost, damage, expenses, including interest, penalties, cost of
investigation and defense, and reasonable attorneys' and other professional fees
and expenses, claims or demands of any kind or nature whatever that arise in any
way out of a Vendor's participation in or medibuy's operation of the New
Commerce Site, including, but not limited to, products liability claims.

        "LOSSES" shall mean any and all losses, actual damages (and not special
or consequential damages), liabilities, costs, and expenses, including interest,
penalties, cost of investigation and defense, and reasonable attorneys' and
other professional fees and expenses.

15.05 INDEMNIFICATION PROCEDURE.

        A Party seeking indemnification under Section 15.04 (the "Indemnified
Party") shall promptly notify the Indemnifying Party in writing of any claim for
indemnification; provided, however, that failure to give such notice shall not
relieve the Indemnifying Party of any liability hereunder (except to the extent
the Indemnifying Party has suffered actual material prejudice by such failure).

        The Indemnified Party shall tender sole defense and control of such
claim to the Indemnifying Party. The Indemnified Party shall, if requested by
the Indemnifying Party, give reasonable assistance to the Indemnifying Party in
defense of any claim. The Indemnifying Party shall reimburse the Indemnified
Party for any reasonable legal expenses directly incurred from providing such
assistance, as such expenses are incurred.

        The Indemnifying Party shall have the right to consent to the entry of
judgment with respect to, or otherwise settle, an indemnified claim with the
prior written consent of the Indemnified Party, which consent shall not be
unreasonably withheld; provided, however, that the Indemnified Party may
withhold its consent if any such judgment or settlement imposes any unreimbursed
monetary or continuing non-monetary obligation on such Party or does not include
an unconditional release of that Party and its Affiliates from all liability in
respect of claims that are the subject matter of the indemnified claim.



24
<PAGE>   29
                                                               SIGNATURE VERSION

15.06 INFRINGEMENT INDEMNITY.

        Each Party (the "Indemnifying Party") shall defend, indemnify, and hold
harmless the other Party (the "Indemnified Party") and all its employees,
officers, directors and agents at Indemnifying Party's expense from and against
any and all claims, lawsuits, actions, decrees, judgments, orders, injunctions,
or demands of any kind, including court costs, expenses and reasonable
attorney's fees, to the extent that such claim, lawsuit, action, decree,
judgment, order, injunction, or demand of any kind is based on a claim that the
WebMD Professional Site, Look and Feel or any frame served by WebMD around the
New Commerce Site, when WebMD is the Indemnifying Party, or the MEDIBUY Site or
New Commerce Site (other than the Look and Feel or any frame served by WebMD
around the New Commerce Site, when MEDIBUY is the Indemnifying Party, infringes
a patent or copyright or the trade secret, IP Right or other proprietary right
of a Third Party ("Infringement"), provided that Indemnifying Party is notified
within 15 days in writing by Indemnified Party as to any such action and is
given full authority, information, and assistance (at Indemnifying Party's
expense) for the defense thereof and the right to control and direct the
investigation, preparation, defense, and settlement of such action provided a
failure to notify the Indemnifying Party as provided in this Section shall not
relieve any Party from its obligation to provide indemnification to extent such
failure is not prejudicial. This paragraph states an Indemnifying Party's sole
liability with respect to claims of Infringement.

15.07 NO OTHER REPRESENTATIONS OR WARRANTIES.

        Each Party acknowledges that the other Party makes no representations,
warranties or agreements related to the subject matter hereof that are not
expressly provided for in this Agreement.

15.08 REMEDIES CUMULATIVE.

        Except as otherwise expressly specified herein, the rights and remedies
granted to each Party under this Agreement are cumulative and in addition to,
and not in lieu of, any other rights or remedies that such Party has under the
express terms of this Agreement.

                       16. DISCLAIMER OF OTHER WARRANTIES.

        EACH PARTY HEREBY ACKNOWLEDGES AND AGREES THAT, EXCEPT AS EXPLICITLY
PROVIDED FOR IN ARTICLE 15, THE OTHER PARTY MAKES NO REPRESENTATIONS OR
WARRANTIES, EXPRESS OR IMPLIED, AS TO (A) THE USEFULNESS, ACCURACY,
COMPLETENESS, FEASIBILITY, RELIABILITY OR EFFECTIVENESS OF SUCH PARTY'S SITES OR
IP RIGHTS; (B) THAT SUCH PARTY'S SITES WILL OPERATE UNINTERRUPTED OR ERROR-FREE;
OR (C) THAT DEFECTS IN SUCH PARTY'S SITES OR IP RIGHTS HAVE BEEN OR WILL BE
CORRECTED. WITHOUT LIMITING THE FOREGOING, EACH PARTY HEREBY DISCLAIMS ALL
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL EITHER PARTY BE LIABLE TO THE OTHER PARTY FOR
ANY



25
<PAGE>   30
                                                               SIGNATURE VERSION

DAMAGES CAUSED BY THE FAILURE, DISRUPTION, DOWNTIME, INTERRUPTION, INCORRECT
LINKAGE, DELAY, INACCURACY OR OTHER NONPERFORMANCE OF SUCH PARTY'S SITES.

                          17. LIMITATION OF LIABILITY.

        EXCEPT IN THE EVENT OF WILLFUL MISCONDUCT OR A CLAIM PURSUANT TO
INDEMNIFICATION OBLIGATIONS UNDER SECTIONS 15.06 or 15.04(b) HEREIN, IN NO EVENT
SHALL A PARTY TO THIS AGREEMENT BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL
OR CONSEQUENTIAL DAMAGES, INCLUDING, WITHOUT LIMITATION, FOR LOST PROFITS, IN
ANY WAY ARISING OUT OF OR RELATING TO THIS AGREEMENT, EVEN IN THE EVENT SUCH
PARTY HAS BEEN ADVISED AS TO THE POSSIBILITY OF SUCH DAMAGES.

                              18. CONFIDENTIALITY.

18.01 CONFIDENTIAL INFORMATION.

        "Confidential Information" means information about the disclosing
Party's business or activities that are proprietary or confidential, other than
Trade Secrets, which are marked or designated by such Party as "confidential" or
"proprietary;" that is of value to a Party. "Trade Secret" means any information
of a Party which (i) derives economic value, actual or potential, from not being
generally known to and not being readily ascertainable by proper means by other
persons who can obtain economic value from its disclosure or use, and (ii) is
the subject of efforts that are reasonable under the circumstances to maintain
its secrecy. No information shall be considered Confidential Information or
Trade Secret of a disclosing Party if it can be shown that such information: (i)
was known to the recipient prior to the date of disclosure by the disclosing
Party directly or indirectly from a source other than one having an obligation
of confidentiality to the disclosing Party; (ii) hereafter becomes known
(independently of disclosure by the disclosing Party) to the recipient directly
or indirectly from a source other than one having an obligation of
confidentiality to the disclosing Party; (iii) becomes publicly known or
otherwise ceases to be confidential, except through a breach of this Agreement
by the recipient; or (iv) was independently developed by the recipient without
use of Confidential Information or a Trade Secret of the other Party.

18.02 PROTECTION OF CONFIDENTIAL INFORMATION.

        The Parties recognize that, in connection with the performance of this
Agreement, each of them may disclose to the other its Confidential Information
and Trade Secrets, including the creation of materials and the development of
technology and techniques that are not generally known in the industry. The
Party receiving any Confidential Information or Trade Secret of the other Party
agrees to maintain the confidential status of such Confidential Information or
Trade Secret and not to use any such Confidential Information or Trade Secret
for any purpose other than the purposes for which it was originally disclosed to
the receiving Party, and not to disclose any of such Confidential



26
<PAGE>   31
                                                               SIGNATURE VERSION

Information to any Third Party until three (3) years after the Termination of
the Agreement and to keep any Trade Secret confidential for as long as it
remains a Trade Secret.

18.03 PERMITTED DISCLOSURE.

        The Parties acknowledge and agree that each may disclose Confidential
Information or a Trade Secret: (i) as required by law; (ii) to their respective
directors, officers, employees, attorneys, accountants and other advisors or
independent contractors, who are under an obligation of confidentiality no less
stringent than set forth herein, on a "need-to-know" basis; (iii) to their
respective Affiliates; or (iv) in connection with disputes or litigation between
the Parties that related to such Confidential Information or Trade Secret and
each Party shall endeavor to limit disclosure to that purpose.

        Confidential Information or a Trade Secret may be disclosed to a legal,
judicial or governmental entity, or as required by the rules or orders of a
court or governmental entity, provided that, before such disclosure, the
recipient shall give reasonable advance notice of such so that the disclosing
Party can seek a protective order or the appropriate protection for the
Confidential Information or Trade Secret.

18.04 APPLICABILITY.

        The foregoing obligations shall apply to directors, officers, employees
and representatives of the Parties and any other Person to whom the Parties have
delivered copies of, or permitted access to, such Confidential Information or
Trade Secret in connection with the performance of this Agreement, and each
Party shall advise each of the above of the obligations set forth in this
Article.

18.05 CONFIDENTIALITY OF THE TERMS OF THIS AGREEMENT.

        Except as required by law (including disclosures necessary or
appropriate in filings with the Securities Exchange Commission or any other
Governmental Body) or generally accepted accounting principles, and except to
assert its rights hereunder or for disclosures on a "need-to-know" basis to its
own officers, directors, employees and professional advisers or to prospective
investors or acquirers in connection with an investment in or acquisition of
such Party, each Party hereto agrees that neither it, nor its directors,
officers, employees, consultants or agents shall disclose the specific terms of
this Agreement without the prior consent of the other Party.

18.06 PUBLIC DISCLOSURE OF THE TERMS OF THIS AGREEMENT.

        Each Party consents to the filing of the Agreement with the U.S.
Securities and Exchange Commission by the other party and to reference such
Party's name and a description of this Agreement in any such filings. In
connection with any public disclosure or filing with any governmental agency,
including the Securities and Exchange Commission, each Party agrees to seek
confidential treatment of the terms and conditions of this Agreement. In
addition, any description of this Agreement, or any redacted version of this
Agreement, intended to be filed or attached to any publicly filed document



27
<PAGE>   32
                                                               SIGNATURE VERSION

by a Party shall be submitted to the other Party for review and input prior to
filing. Notwithstanding anything to the contrary herein, neither Party may use
any Mark of the other Party in any public disclosure or filing with any
governmental agency, including the Securities and Exchange Commission, without
the express written consent of the other Party.

                               19. MISCELLANEOUS.

19.01 PRESS RELEASE.

        The Parties agree to issue a joint press release about this Agreement
promptly upon the Effective Date.

19.02 NO JOINT VENTURE.

        The sole relationship between the Parties shall be that of independent
contractors. No partnership, joint venture, or other formal business
relationship is hereby created between the Parties hereto. Neither Party shall
make any warranties or representations, or assume or create any obligations, on
the other Party's behalf except as may be expressly permitted hereunder or in
writing by such other Party. Each Party shall be solely responsible for the
actions of all their respective employees, agents and representatives.

19.03 GOVERNING LAW.

        This Agreement shall be interpreted and construed in accordance with the
laws of the State of California without regard to the principles of conflicts of
laws, and with the same force and effect as if fully executed and performed
therein, and the laws of the United States of America.

19.04 AMENDMENT OR MODIFICATION.

        This Agreement may not be amended, modified or supplemented by the
Parties in any manner, except by an instrument in writing signed on behalf of
each of the Parties by a duly authorized officer or representative.

19.05 NO ASSIGNMENT.

        MEDIBUY shall not transfer or assign any rights or delegate any
obligations hereunder including by assignment of this Agreement and the
obligations hereunder to any successor of MEDIBUY by way of merger,
consolidation, reorganization, Change of Control or the acquisition of
substantially all of the business and assets of MEDIBUY relating to the
Agreement to any WebMD Competitor in whole or in part, whether voluntarily or by
operation of law. WebMD shall not transfer or assign any rights or delegate any
obligations hereunder including by assignment of this Agreement and the
obligations hereunder to any successor of WebMD by way of merger, consolidation,
reorganization, Change of Control or the acquisition of substantially all of the
business and assets of WebMD relating to the Agreement to any MEDIBUY Competitor
in whole or in part, whether voluntarily or by operation of law. Any purported
transfer, assignment



28
<PAGE>   33
                                                               SIGNATURE VERSION

or delegation by either Party in violation of the above restrictions shall be
null and void and of no force or effect. An assignment will not relieve a Party
to this Agreement of any obligations under this Agreement.

19.06 NOTICES.

        Any notice or other communication to be given hereunder shall be in
writing and shall be (as elected by the Party giving such notice): (i)
personally delivered; (ii) transmitted by postage prepaid registered or
certified mail, return receipt requested; (iii) deposited prepaid with a
nationally recognized overnight courier service; or (iv) sent by facsimile.
Unless otherwise provided herein, all notices shall be deemed to have been duly
given on: (a) the date of receipt (or if delivery is refused, the date of such
refusal) if delivered personally or by courier; (b) three (3) days after the
date of posting if transmitted by mail; or (c) if transmitted by facsimile, the
date a confirmation of transmission is received. Either Party may change its
address for purposes hereof on not less than three (3) days prior notice to the
other Party. Notices hereunder shall be directed to, unless otherwise instructed
by the receiving Party:

        If to MEDIBUY to:

                             MEDIBUY.com, Inc.
                             10120 Pacific Heights Boulevard, Suite 100
                             San Diego, CA  92121
                             Attn: Chief Financial Officer
                             Fax: 858-550-5039

        With a Copy to (which shall not constitute notice):

                             Cooley Godward LLP
                             4365 Executive Drive, Suite 1100
                             San Diego, CA  92121
                             Attn: Jeremy D. Glaser, Esq.
                             Fax: 858-453-3555

        If to WebMD, to:

                             Healtheon/WebMD Corporation
                             3399 Peachtree Road
                             Suite 400
                             The Lenox Building
                             Atlanta N.E., GA  30326
                             Attn: General Counsel
                             Fax: 404-479-7603



29
<PAGE>   34
                                                               SIGNATURE VERSION

        With a copy to (which shall not constitute notice):

                             Alston & Bird LLP
                             One Atlantic Center
                             1201 W. Peachtree Street
                             Atlanta, GA 30309-3424
                             Attn: James A. Harvey
                             Fax: 404-881-7777

19.07 ENTIRE AGREEMENT.

        This Agreement represents the entire agreement of the Parties with
respect to the subject matter hereof and supersedes all prior and/or
contemporaneous agreements and understandings, written or oral between the
Parties with respect to the subject matter hereof.

19.08 WAIVER.

        Any of the provisions of this Agreement may be waived by the Party
entitled to the benefit thereof. Neither Party shall be deemed, by any act or
omission, to have waived any of its rights or remedies hereunder unless such
waiver is in writing and signed by the waiving Party, and then only to the
extent specifically set forth in such writing. A waiver with reference to one
event shall not be construed as continuing or as a bar to or waiver of any right
or remedy as to a subsequent event.

19.09 NO THIRD PARTY BENEFICIARIES.

        Nothing express or implied in this Agreement is intended to confer, nor
shall anything herein confer, upon any Person other than the Parties and the
respective successors or assigns of the Parties, any rights, remedies,
obligations or liabilities whatsoever.

19.10 FEES AND EXPENSES.

        Each Party shall be responsible for the payment of its own costs and
expenses, including attorney's fees and expenses, in connection with the
negotiation and execution of this Agreement.

19.11 SEVERABILITY.

        If the application of any provisions of this Agreement to any particular
facts of circumstances shall be held to be invalid or unenforceable by any court
of competent jurisdiction, then: (i) the validity and enforceability of such
provision or provisions as applied to any other particular facts or
circumstances and the validity of other provisions of this Agreement shall not
in any way be affected or impaired thereby; and (ii) such provision or
provisions shall be reformed without further action by the Parties hereto and
only to the extent necessary to make such provision or provisions valid and
enforceable when applied to such particular facts and circumstances.



30
<PAGE>   35
                                                               SIGNATURE VERSION

19.12 COUNTERPARTS; FACSIMILES.

        This Agreement may be executed in any number of counterparts, each of
which when so executed and delivered shall be deemed an original, and such
counterparts together shall constitute one and the same instrument. Each Party
shall receive a duplicate original of the counterpart copy or copies executed by
it. For purposes hereof, a facsimile copy of this Agreement, including the
signature pages hereto, shall be deemed to be an original. Notwithstanding the
foregoing, the Parties shall each deliver original execution copies of this
Agreement to one another as soon as practicable following execution thereof.

19.13 INSURANCE.

        Throughout the Term, each Party shall procure and maintain at its own
expense insurance naming the other Party as an additional insured and an
additional loss payee, solely for purposes of the indemnification provisions of
this Agreement which insurance must be satisfactory to other Party, of the
following types and in the following amounts: at least $2 million in general
liability insurance, which, in the case of WebMD, contains a rider or provision
that expressly covers losses and claims made in connection with WebMD's
provision of content over the Internet to Third Parties, and in the case of
MEDIBUY, contains a rider or provision that expressly covers losses and claims
made in connection with MEDIBUY's operation of the New Commerce Site, and
umbrella liability insurance coverage in the amount of $4 million. All insurance
to be maintained by a Party under this Section shall be with companies licensed
to do business in the State of California for MEDIBUY and Georgia for WebMD and
reasonably acceptable to the other Party. Each Party shall furnish to the other
Party certificates of insurance or other appropriate documentation (including
evidence of renewal of insurance) evidencing all coverage referenced in this
Section. Such certificates or other documentation will include a provision
whereby thirty (30) days' notice must be received by the other Party prior to
cancellation or material alteration of the coverage by either a Party or the
insurer in question.



31
<PAGE>   36
                                                               SIGNATURE VERSION

        IN WITNESS WHEREOF, the duly authorized representatives of the Parties
of have executed this Agreement as of the date first written below.



ATTEST:                                      MEDIBUY.COM, INC.



By:     /s/ Matt Feiner                      By:  /s/ Norman Farquhar
    ----------------------------------           -------------------------------
Name:  Matt Feiner                           Name:  Norman Farquhar
       -------------------------------              ----------------------------

Title: Controller                            Title: Executive V.P. & CFO
       -------------------------------              ----------------------------

DATE:      1/18/00                           DATE:       1/18/00
       -------------------------------              ----------------------------



ATTEST:                                      HEALTHEON/WebMD CORPORATION



By:  /s/ Joseph H. Ashlconti                 By:   /s/ Jeffrey T. Arnold
    ----------------------------------           -------------------------------

Name:    Joseph H. Ashlconti                 Name:  Jeffrey T. Arnold
       -------------------------------              ----------------------------

Title: Assistant General Counsel & V.P       Title:     CEO
       -------------------------------              ----------------------------

DATE:     1/18/00                            DATE:    1/18/00
       -------------------------------              ----------------------------



32
<PAGE>   37
                                                               SIGNATURE VERSION

        Exhibit 1.02 - Index of Terms Defined in the body of the Agreement.


<TABLE>
<S>                                                   <C>
Aggregate Information..............................................Section 12.02
Agreement........................................................First Paragraph
Arbitration Firm...................................................Section 11.03
Confidential Information...........................................Section 18.01
Contract Manager...................................................Section 10.01
Dispute Date.......................................................Section 11.01
Effective Date...................................................First Paragraph
Harmful Items.......................................................Section 6.04
Illicit Items......................................................Section 6.021
Indemnified Party..................................................Section 15.05
Indemnifying Party.................................................Section 15.04
Infringement.......................................................Section 15.06
Losses.............................................................Section 15.04
Material Breach....................................................Section 14.02
MEDIBUY..........................................................First Paragraph
MEDIBUY Competitor..................................................Section 7.01
MEDIBUY Services.......................................................Recital A
MEDIBUY Site...........................................................Recital A
New Commerce Site................................................Section 3.02(a)
New Commerce Site Development Plan....................Section 4.02(a). Section 2
New Product.........................................................Section 6.02
Physician Buyer.....................................................Section 7.01
Removal Period......................................................Section 6.05
Substitute Product..................................................Section 6.02
Term...............................................................Section 14.01
Transition Page..........................................................3.02(a)
URL....................................................................Recital A
WebMD............................................................First Paragraph
WebMD Competitor....................................................Section 7.01
WebMD Consumer Site....................................................Recital A
WebMD Consumer Start Page..............................................Recital A
WebMD Exclusive Rights..............................................Section 7.04
WebMD Home Page........................................................Recital A
WebMD Professional Site................................................Recital A
WebMD Site.............................................................Recital A
</TABLE>



33
<PAGE>   38

                 Exhibit 4.01 - Technical Performance Standards.

        1.  PERFORMANCE

        A) All pages of the New Commerce Site must load quickly: the average
page load time must be no more than 5 seconds below the Keynote Business 40.
(For example, in September 1999, this average was 5.51 seconds, on a T1 as
measured by the Keynote monitoring service from different Keynote agents across
the Internet.).

        B) All pages of the New Commerce Site must average 99.3% up time, as
measured by Keynote monitoring service.

        C) The New Commerce Site must post a mutually approved message in the
event of a system outage.

        D) Measurements in this Section 1 are to be made on a monthly basis.

        2.  MONITORING/REPORTING

        A) MEDIBUY or MEDIBUY's supplier of web hosting services must use
Keynote monitoring service, or other similar service approved by MEDIBUY and
reasonably acceptable to WebMD, to provide daily monitoring of the New Commerce
Site performance and availability.

        B) MEDIBUY will provide to WebMD weekly or other appropriate periodic
reports which detail server up time with the following details per period:

        (i) average response time;

        (ii) actual daily response time detail;

        (iii) average server up time; and

        (iv) actual daily server up time.

        C) This information will be e-mailed to WebMD's Contract Manager each
Monday for the previous period's reports.

        3.  ESCALATION PROCEDURES

        A) MEDIBUY will notify, or will cause its supplier of web hosting
services, to notify WebMD within ten (10) minutes of a service outage: Status
information to include:

        (i) reason for the outage; and

        (ii) ETA for service restoration.



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<PAGE>   39
                                                               SIGNATURE VERSION

        B) Notification to WebMD shall occur by the following communications
channels (or other channels designated by WebMD from time to time):

               outages@webmd.net

               Nawaf Muallem: 404-307-5086

               Mitch Miller: 404-229-9883

        C) If WebMD becomes aware of a service outage and has not been notified
by e-mail by MEDIBUY or its hosting service provider, WebMD may contact MEDIBUY
and will be given the information listed in 3.A).

        D) MEDIBUY shall continue to notify WebMD with updated status for the
duration of the outage.

        E) MEDIBUY shall also provide a post incident summary including:

        (i) the cause of the problem;

        (ii) method used to correct the problem; and

        (iii) measures MEDIBUY, or its web hosting supplier, will take to
        prevent further occurrences

        4.  BUSINESS RESUMPTION

        A) MEDIBUY, or MEDIBUY's web hosting supplier, must prove the ability to
switch processing from a primary server to a hot backup server within five (5)
minutes.

        B) MEDIBUY, or MEDIBUY's web hosting supplier, must perform an analysis
that documents all of the single points of failure in MEDIBUY's web site system,
including network components such as routers, hardware and software components.

        C) MEDIBUY, or MEDIBUY's web hosting supplier, must eliminate all of the
single points of failure within MEDIBUY's web site system, within three (3)
months from the date of this Agreement.



35
<PAGE>   40

                                  Exhibit 8.01

                          MEDIBUY SERVICES DESCRIPTIONS


        eAUCTION. Our eAuction service, launched in June 1999, gives users the
opportunity to buy and sell new and used equipment in an auction style format.
Through eAuction, buyers can access information about and submit bids for items
being auctioned by sellers. Buyers can browse available auctioned products or
conduct specific searches through hundreds of products ranging from pre-owned,
"as-is" products to reconditioned and seller-warranted products.


        Through eAuction, sellers can maximize the value of their excess assets
by offering them for sale on a worldwide basis. The auction style format helps
distributors, manufacturers and healthcare providers by automating and reducing
the costs of liquidating excess inventory.


        eRFP. Our eRFP service, launched in April 1999, automates and reduces
inefficiencies in the request-for-proposal process for the procurement of
healthcare supplies. Through eRFP, a buyer can anonymously submit a
request-for-proposal, commonly known as an RFP, to sellers registered within the
product categories selected by the buyer. In this manner, buyers can submit RFPs
for items in our eCatalog as well as other items and services not currently in
our eCatalog. Sellers can then submit proposals in response to the RFP. Finally,
the buyer can review aggregated responses and accept the proposal that best
meets its needs. eRFP gives sellers an equal opportunity to submit proposals
against RFPs in an anonymous setting and is designed to lower costs and reduce
the time required for buyers to locate products and services.


        eCATALOG. Our eCatalog service, launched in December 1999, provides our
buyers with ability to purchase a large variety of products and services
available through our Web site's electronic catalog. Buyers can use eCatalog to
compare products based on product characteristics and price and to purchase and
automatically re-order products and services.


        The information provided through our eCatalog service is electronically
linked with our sellers' databases, ensuring current and accurate seller pricing
and immediate access to available inventory information. Our eCatalog service
provides consistently updated seller information reflecting changes to a
seller's product database. In addition, our eCatalog service coordinates
buyer-specific pricing structures to offer buyers either current market pricing
or specific pre-negotiated contract pricing. eCatalog enables sellers to provide
targeted electronic marketing information to accompany their product listings,
allowing them to compete on product features and not just price. Should a buyer
ultimately decide that a product's price, availability or other terms are not
attractive, the buyer can immediately use eRFP to solicit proposals from
potential sellers in an attempt to improve these terms.

<PAGE>   41

                                  Exhibit 9.01



            MEDIBUY MARKS                                 WebMD MARKS
---------------------------------------         --------------------------------

               MEDIBUY                                       WEBMD

<PAGE>   42
                                                               SIGNATURE VERSION


                    MODIFICATION OF JOINT MARKETING AGREEMENT



38
<PAGE>   43
                                                               SIGNATURE VERSION

        March 3, 2000


        Chief Executive Officer
        Healtheon/WebMD Corporation.
        3399 Peachtree Road
        Suite 400
        The Lenox Building
        Atlanta N.E., GA  30326



RE:     MODIFICATION OF JOINT MARKETING AND PROMOTION AGREEMENT


        The purpose of this letter is to modify certain provisions of the Joint
Marketing and Promotion Agreement (the "Agreement") between medibuy.com, Inc.
("MEDIBUY") and Healtheon/WebMD Corporation ("WebMD") and to memorialize certain
recent discussions between the parties.


        As you know, MEDIBUY is in discussions with Premier, Inc. ("Premier")
relating to an e-commerce outsourcing agreement under which medibuy or its
affiliate will provide e-commerce services to Premier and its members and
affiliates (the "E-Commerce Outsourcing Agreement"). Premier has raised concerns
about our ability to effectively implement such transactions in light of the
terms of the Agreement. In view of these developments, the following
modifications and acknowledgements are made:


        The parties agree that:


-   the definition of "Physician Buyer" in the Agreement (Section 7.01) shall
    specifically exclude any physicians, physician groups or outpatient clinics
    that are participants in programs operated by Premier or its affiliates
    ("Premier Programs") and are owned, employed or managed by Premier, Premier
    members or their affiliates.


-   the definition of "WebMD Competitor" in the Agreement used in Section 7.04
    (i) (but not with respect to the New Commerce Site) and Section 7.04 (ii)
    shall specifically exclude Premier and any of its affiliates, and any
    services or offerings that are directed to physicians, physician groups, or
    outpatient clinics that are provided, sponsored or managed by Premier or its
    affiliates or members of Premier or its affiliates. Provided, the existence
    of Provider Select as an affiliate of Premier or such other affiliate of
    Premier principally engaged in providing products or services to physicians,
    physician groups or outpatient clinics (the "Other Premier Affiliate") shall
    not be deemed to make Premier or its other affiliates a WebMD Competitor for
    the purposes of the Agreement. Provided further, that for the purposes of
    Sections 7.04(i) and Section 7.04 (ii), Provider Select and the Other
    Premier Affiliate shall not be excluded from the definition of a WebMD
    Competitor. Notwithstanding anything



39
<PAGE>   44
                                                               SIGNATURE VERSION

    to the contrary herein or in the Agreement, MEDIBUY shall not (i) place an
    Action Link to, or an On-Line Advertisement or any other advertisement or
    promotion for any Premier Program on any Page of the New Commerce Site or
    publicly available non-password protected Page of the MEDIBUY Site that
    includes a direct link to a Premier Program that is principally engaged in
    providing products or services to physicians, physician groups or outpatient
    clinics that are not owned, employed or managed by Premier, Premier members
    or their affiliates; or (ii) otherwise advertise or promote to any
    non-Premier members or Premier affiliates any Premier Program that is
    principally engaged in providing products or services to physicians,
    physician groups or outpatient clinics that are not owned, employed or
    managed by Premier, Premier members or their affiliates, whether in off-line
    media or in on-line media, or in any communication made by or on behalf of
    MEDIBUY, including, e-mail, direct mail, or advertising sent or communicated
    by MEDIBUY to its Vendors and buyers in any manner.


        WebMD hereby consents to the potential transaction between medibuy and
Premier, including (i) the issuance of equity securities of medibuy in excess of
40% of the total outstanding equity securities of medibuy and (ii) the entering
into of the E-Commerce Outsourcing Agreement provided, during the term of the
Agreement, that no e-commerce services shall be provided by medibuy under such
agreement to Premier's Provider Select affiliate or Other Premier Affiliate
without the consent of WebMD which may be withheld in the sole discretion of
WebMD.


        For the purposes of this letter an "affiliate" means, with respect to an
entity, any person that, directly or indirectly, Controls, or is Controlled by,
or is under common Control with, such entity. "Controls, Controlled by, or under
common Control with" means the possession, directly or indirectly, of the power
to direct or cause the direction of the management and policies of a person,
whether by contract or through the ownership of voting securities, including the
ownership of more than fifty percent (50%) of the equity, partnership,
membership or similar interest in such person.

Please sign this letter below to acknowledge your agreement and approval of the
foregoing. This letter may be executed in any number of counterparts, each of
which shall be deemed an original, and all of which when taken together shall
constitute one and the same instrument. Except only as acknowledged above, all
of the terms and provisions of the Agreement shall continue unchanged and in
full force and effect.

Very truly yours,

MEDIBUY.COM, INC.



By:    /s/ Dennis Murphy
     -------------------------------------
     Dennis Murphy
     President and Chief Executive Officer



40
<PAGE>   45
                                                               SIGNATURE VERSION


Accepted and Agreed as of   ____________, 2000

HEALTHEON/WebMD CORPORATION



By:    /s/ Geoffrey Rutledge
     -------------------------------------
     Geoffrey Rutledge
     Vice President, Business Development



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