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                                                                   EXHIBIT 10.4


                          HEALTHEON/WEBMD CORPORATION
                         REGISTRATION RIGHTS AGREEMENT


         This Registration Rights Agreement (the "AGREEMENT") is made and
entered into as of the 26th day of January, 2000, among Healtheon/WebMD
Corporation, a Delaware corporation (the "COMPANY"), and the parties set forth
on signature pages hereto (each a "PURCHASER" and collectively, the
"PURCHASERS").

                                   RECITALS:

         A.       The Purchasers have purchased 2 million shares of the
Company's Common Stock, par value $0.0001 per share (the "COMMON STOCK") and
155,951 shares of the Company's Series A Preferred Stock, par value $0.0001 per
share (the "SERIES A STOCK") pursuant to a Purchase Agreement dated as of the
26th day of January, 2000, (the "PURCHASE AGREEMENT") between the Company, the
Purchasers and the other parties thereto.

         B.       The Company may issue to the Purchasers up to an additional
10,291,939 shares of Common Stock upon the occurrence of certain events set
forth in the Amended and Restated Limited Liability Company Agreement of Health
Network LLC dated as of the 26th day of January, 2000, and in the Limited
Liability Company Agreement of WebMD International LLC dated as of the 26th day
of January, 2000.

         C.       The Company and the Purchasers desire to set forth the
registration rights to be granted by the Company to the Purchasers.

         NOW, THEREFORE, in consideration of the mutual promises,
representations, warranties, covenants, and conditions set forth herein and in
the other Transaction Documents (as defined below), the parties mutually agree
as follows:

                                  AGREEMENT:

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

         "Certificate of Incorporation" means the Amended and Restated
Certificate of Incorporation of the Company as filed with the Secretary of
State of the State of Delaware, as amended from time to time.

         "Commission" shall mean the Securities and Exchange Commission or any
other federal agency at the time administering the Securities Act.

         "Common Stock" shall mean the common stock, par value $0.0001 per
share, of the Company and any and all shares of capital stock or other equity
securities of: (i) the Company which are added to or exchanged or substituted
for the Common Stock by reason of the declaration of any stock dividend or
stock split, the issuance of any distribution or the reclassification,
readjustment, recapitalization or other such modification of the capital
structure of the Company; and (ii) any other corporation, now or hereafter
organized under the laws of any state or other governmental authority, with
which the


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Company is merged, which results from any consolidation or reorganization to
which the Company is a party, or to which is sold all or substantially all of
the shares or assets of the Company, if immediately after such merger,
consolidation, reorganization or sale, the Company or any Stockholders of the
Company own equity securities having in the aggregate more than fifty percent
(50%) of the total voting power of such other corporation.

         "Exchange Act" shall mean the Securities Exchange Act of 1934, as
amended, and the rules and regulations of the Commission promulgated
thereunder.

         "Family Member" shall mean (a) with respect to any individual, such
individual's spouse, any descendants (whether natural, adopted or in the
process of adoption), any trust all of the beneficial interests of which are
owned by any of such individuals or by any of such individuals together with
any organization described in Code Section 501(c)(3), the estate of any such
individual, and any corporation, association, partnership or limited liability
company all of the equity interests of which are owned by those above described
individuals, trusts or organizations and (b) with respect to any trust, the
owners of the beneficial interests of such trust.

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

         "HCNLLC LLC Agreement" means the Amended and Restated Limited
Liability Company Agreement of Health Network LLC as of the 26th day of
January, 2000.

         "Holder" shall mean each of the Purchasers or any of such Holder's
respective successors and assigns who acquire rights in accordance with this
Agreement with respect to the Registrable Securities directly or indirectly
from such Holder.

         "Initiating Holders" shall mean any Holder or Holders of not less than
50% of the then outstanding Registrable Securities.

         "News Corp" means The News Corporation Limited, a South Australia,
Australia corporation.

         The terms "register", "registered" and "registration" refer to a
registration effected by preparing and filing a registration statement in
compliance with the Securities Act, and the declaration or ordering of the
effectiveness of such registration statement.

         "Registrable Securities" means shares of Common Stock issued pursuant
to the Purchase Agreement, the HCNLLC LLC Agreement and the WebMD International
LLC Agreement and the shares of Common Stock into which the shares of Preferred
Stock issued pursuant to the Purchase Agreement are convertible pursuant to the
Certificate of Incorporation, excluding in all cases, however (including
exclusion from the calculation of the number of outstanding Registrable
Securities), any Registrable Securities sold by a person in a transaction (i)
pursuant to a registration statement under Section 2, 3 or 4 hereof or (ii)
pursuant to Rule 144 (or any successor provision) of the Securities Act.

         "Securities Act" shall mean the Securities Act of 1933, as amended, or
any similar federal statute promulgated in replacement thereof, and the rules
and regulations of the Commission thereunder, all as the same shall be in
effect at the time.


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         "Transaction Documents" shall have the meaning set forth in the Master
Strategic Alliance Agreement dated December 6, 1999 among the Company, News
Corp and Fox Entertainment Group, Inc., a Delaware corporation which is
controlled by News Corp.

         "WebMD International LLC Agreement" means the Limited Liability
Company Agreement of WebMD International Limited dated as of the 26th day of
January, 2000.

         2.       Demand Registration. In case the Company shall receive from
Initiating Holders a written request that the Company effect a registration
with respect to at least 2,000,000 shares of Common Stock that constitute
Registrable Securities (as adjusted for stock splits, stock dividends,
recapitalizations and similar events) the Company will:

         (a)      promptly give written notice of the proposed registration to
all other Holders so they may have an opportunity to consider joining in such
registration, which they may do (subject to the terms and provisions of this
Agreement) at their election within ten (10) days after receipt of the notice
of the proposed registration by the Company; and

         (b)      as soon as practicable, use its reasonable best efforts to
effect such registration (including, without limitation, the execution of an
undertaking to file post-effective amendments, appropriate qualification under
applicable blue sky or other state securities laws and appropriate compliance
with applicable regulations issued under the Securities Act) as may be so
requested and as would permit or facilitate the sale and distribution of all or
such portion of such Registrable Securities as are specified in such request,
together with all or such portion of the Registrable Securities of any Holder
or Holders joining in such request as are specified in a written request given
within ten (10) days after receipt of notice from the Company pursuant to
Section 2(a); provided that the Company shall not be obligated to take any
action to effect any such registration, qualification or compliance pursuant to
this Section 2:

                  (i)      In any particular jurisdiction in which the Company
would be required to execute a general consent to service of process in
effecting such registration, qualification or compliance unless the Company is
already subject to service in such jurisdiction and except as may be required
by the Securities Act;

                  (ii)     Prior to June 30, 2000;

                  (iii)    Within the one hundred twenty (120) day period
immediately following the effective date of a registration statement pertaining
to a firm commitment underwritten public offering of Common Stock for the
account of a shareholder (including Purchaser) of the Company who has exercised
a demand right to register shares of Common Stock (other than a registration
relating solely to a Commission Rule 145 transaction, a registration relating
solely to employee benefit plans, or a registration statement on Form S-3 (or
any similar short-form registration statement));

                  (iv)     Within the sixty (60) day period immediately
following the effective date of a registration statement on Form S-3 (or any
similar short-form registration statement) pertaining to a firm commitment
underwritten public offering of Common Stock for the account of another
shareholder of the Company who has exercised a demand right to register shares
of Common Stock (other than a


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registration relating solely to a Commission Rule 145 transaction or a
registration relating solely to employee benefit plans); or

                  (v)      After the Company has effected three (3)
registrations pursuant to this Section 2 and such registrations have been
declared or ordered effective and have remained effective for a period of at
least ninety (90) consecutive days.

         Subject to the foregoing clauses (i) through (v), the Company shall
file a registration statement covering the Registrable Securities so requested
to be registered as soon as practicable after receipt of the request of the
Initiating Holders. The Initiating Holders may, at any time prior to the
effective date of the registration statement relating to such registration,
revoke such request, without liability (except as set forth in Section 6
hereof) to the Initiating Holders or any other Holders of Registrable
Securities requested to be registered pursuant to Section 2(a) hereof, by
providing a written notice to the Company revoking such request.

         Notwithstanding the above, the Company shall not be obligated to
effect, or to take any action to effect, any registration pursuant to this
Section 2 during the period starting with the date ninety (90) days prior to
the Company's good faith estimate of the date of filing of (or in the case of
any registration on Form S-3, forty-five (45) days prior), and ending on a date
one hundred twenty(120) days after the effective date of (or in the case of any
registration on Form S-3, ninety (90) days after), a Company-initiated
registration statement in connection with a bona fide firm commitment
underwritten registration for securities to be offered for the Company's own
account (the "Intended Registration"); provided that the Company is actively
employing in good faith all reasonable efforts to cause the Intended
Registration to become effective and provided further that the Company gives
notice to all Holders upon commencement of such period. The Holders shall be
entitled to exercise their rights pursuant to Section 4 hereof with respect to
an Intended Registration. An Intended Registration shall not be deemed to be a
demand registration of the Holders pursuant to this Section 2.

         (c)      Underwriting. If the Holders propose an underwritten
offering, the sale of Registrable Securities pursuant to this Section 2 must be
made by means of a firm commitment underwriting through underwriters who are
reasonably acceptable to the Company and the holders of a majority of the
Registrable Securities that are proposed to be distributed through such
underwriting. The right of any Holder to registration pursuant to this Section
2 shall be conditioned upon such Holder's participation in such underwriting
and the inclusion of such Holder's Registrable Securities in the underwriting
to the extent requested by such Holder (unless mutually otherwise agreed by a
majority in interest of the Holders and such Holder) to the extent provided
herein.

         The Company and all Holders proposing to distribute Registrable
Securities through such underwriting shall enter into an underwriting agreement
in customary form with the underwriter or underwriters selected for such
underwriting. Notwithstanding any other provision of this Section 2(c), if the
underwriter determines that in its good faith view marketing factors require a
limitation of the number of shares to be underwritten and so advises the
Initiating Holders in writing, then the Initiating Holders shall so advise the
Company and all Holders (except those Holders who have indicated to the Company
their decision not to distribute any of their Registrable Securities through
such underwriting) and the number of Registrable Securities that may be
included in the registration and underwriting shall be allocated first to the
Holders on a pro rata basis according to the number of Registrable Securities
requested to be included by the Holders; second to the Company; and third to
other shareholders of the Company who have requested to sell in the
registration. No Registrable Securities excluded from the underwriting by
reason of the underwriter's marketing limitation shall be included in such
registration.


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If at least eighty percent (80%) of the Registrable Securities requested to be
registered by the Initiating Holders are not included in such registration,
then the Initiating Holders may request that the Company effect an additional
registration under the Securities Act of all or part of the Initiating Holders'
Registrable Securities in accordance with the provisions of this Section 2, and
the Company shall effect such additional registration.

         If any Holder disapproves of the terms of the underwriting, such
person may elect to withdraw therefrom by written notice to the Company, the
underwriter and the Initiating Holders. The Registrable Securities and/or other
securities so withdrawn from such underwriting shall also be withdrawn from
such registration; provided, however, that, if by the withdrawal of such
Registrable Securities a greater number of Registrable Securities held by other
Holders may be included in such registration (up to the maximum of any
limitation imposed by the underwriters), then the Company shall offer to all
Holders who have included Registrable Securities in the registration the right
to include additional Registrable Securities in the same proportion used above
in determining the underwriter limitation.

         If the underwriter has not limited the number of Registrable
Securities to be underwritten, the Company may include securities for its own
account or the account of others in such registration if the underwriter so
agrees and if the number of Registrable Securities which would otherwise have
been included in such registration and underwriting will not thereby be
limited.

         (d)      If the Company shall furnish to the Initiating Holders a
certificate signed by the President of the Company stating that, in the good
faith judgment of the Board of Directors of the Company, it would (because of
the existence of, or in anticipation of, any acquisition, financing activity,
or other transaction involving the Company, or the unavailability for reasons
beyond the Company's control of any required financial statements, disclosure
of information which is in its best interest not to publicly disclose, or any
other event or condition of similar significance to the Company) be seriously
detrimental to the Company and its shareholders for such registration statement
to be filed on or before the date filing would be required and it is therefore
essential to defer the filing of such registration statement, then the Company
may direct that such request for registration be delayed for a period not in
excess of ninety (90) days, such right to delay a request to be exercised by
the Company not more than twice in any twelve (12) month period.

         (e)      Effective Registration Statement. A demand registration
requested pursuant to this Section 2 shall not be deemed to have been effected
unless the registration statement relating thereto (i) has become effective
under the Securities Act and any of the Registrable Securities of the
Initiating Holders included in such registration have actually been sold
thereunder, and (ii) has remained effective for a period of at least ninety
(90) days (or such shorter period in which all Registrable Securities included
in such registration have actually been sold thereunder).

         3.       S-3 Registration. In case the Company shall receive from any
Holder or Holders a written request or requests that the Company effect a
registration on Form S-3 and any related qualification or compliance with
respect to all or a part of the Registrable Securities owned by such Holder or
Holders, the Company will:

         (a)      promptly give written notice of the proposed registration,
and any related qualification or compliance, to all other Holders; and


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         (b)      as soon as practicable, and in any event within 30 days of
the receipt of such notice, file a registration statement on Form S-3 and
effect all other qualifications and compliances as may be so requested and as
would permit or facilitate the sale, distribution, transfer or hedging (through
market transactions using brokers, in a firm commitment underwriting, in
negotiated transactions or otherwise) of all or such portion of such Holder's
or Holders' Registrable Securities as are specified in such request, together
with all or such portion of the Registrable Securities of any other Holder or
Holders joining in such request as are specified in a written request given
within 15 days after receipt of such written notice from the Company; provided,
that the Company shall not be obligated to effect any such registration,
qualification or compliance pursuant to this Section 3:

                  (i)      if Form S-3 is not available for such offering by
the Holders;

                  (ii)     if the Holders, together with the holders of any
other securities of the Company entitled to inclusion in such registration,
propose to register Registrable Securities and such other securities (if any)
at an aggregate price to the public (net of any underwriters' discounts or
commissions) of less than $20 million;

                  (iii)    if the Company has, within the twelve (12) month
period preceding the date of such request, already effected three (3)
registrations for the Holders pursuant to this Section 1.3; or

                  (iv)     in any particular jurisdiction in which the Company
would be required to qualify to do business or to execute a general consent to
service of process in effecting such registration, qualification or compliance.

         (c)      Subject to the foregoing, the Company shall file a
registration statement covering the Registrable Securities and other securities
so requested to be registered as soon as practicable after receipt of the
request or requests of the Holders and shall keep it continuously effective
until such Registrable Securities have been sold pursuant thereto.

         (d)      Notwithstanding the other provisions of this Section 3, the
Company shall have the right to delay the filing of any registration statement
on Form S-3 (an "S-3 Registration") otherwise required to be prepared and filed
by the Company pursuant to this Section 3, or to suspend the use of any S-3
Registration, for a period not in excess of 60 days (a "S-3 BLACKOUT PERIOD")
if the Company, in the good faith judgment of its Board of Directors,
determines (because of the existence of, or in anticipation of, any
acquisition, financing activity, or other transaction involving the Company, or
the unavailability for reasons beyond the Company's control of any required
financial statements, disclosure of information which is in its best interest
not to publicly disclose, or any other event or condition of similar
significance to the Company) that the registration and distribution of the
Registrable Securities to be covered by such S-3 Registration would be
seriously detrimental to the Company and its shareholders, provided that the
S-3 Blackout Period shall earlier terminate on the second business day
following the completion or abandonment of the relevant financing, acquisition
or other transaction or upon public disclosure by the Company or public
admission by the Company of such material nonpublic information or such time as
such material nonpublic information shall be publicly disclosed; and provided,
further, that the Company shall furnish to the Holders a certificate of an
executive officer of the Company to the effect that an event permitting a S-3
Blackout Period has occurred (and no other reason need be given). The Company
will promptly give the Holders written notice of such determination and an
approximation of the period of the anticipated delay; provided, however, that
the aggregate number of days included in all S-3 Blackout Periods during any
consecutive 12 months shall not exceed 180 days. Each Holder agrees to cease
all disposition efforts under such S-


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3 Registration with respect to Registrable Securities held by such Holder
immediately upon receipt of notice of the beginning of any S-3 Blackout Period.
The Company shall provide written notice to the Holders of the end of each S-3
Blackout Period.

         4.       Piggyback Registration.

         (a)      If the Company shall determine to register for sale for cash
any of its Common Stock, for its own account or for the account of others
(other than the Holders), other than a registration relating solely to employee
benefit plans or securities issued or issuable to employees, consultants (to
the extent the securities owned or to be owned by such consultants could be
registered on Form S-8) or any of their Family Members (including a
registration on Form S-8), or a registration relating solely to a Commission
Rule 145 transaction, a registration on Form S-4 in connection with a merger,
acquisition, divestiture, reorganization or similar event, the Company promptly
will give to each Holder written notice thereof and shall use its reasonable
best efforts to include in such registration (and any related qualification
under blue sky laws or other compliance), and in any underwriting involved
therein, all the Registrable Securities specified in a written request or
requests, made within ten (10) days after receipt of such written notice from
the Company, by any Holder or Holders. However, the Company may, without the
consent of the Holders, withdraw such registration statement prior to its
becoming effective if the Company has abandoned its proposal to register the
securities proposed to be registered thereby.

         (b)      Underwriting. If the registration of which the Company gives
notice is for a registered public offering involving an underwriting, the
Company shall so advise the Holders as a part of the written notice given
pursuant to Section 4(a). In such event the right of any Holder to registration
pursuant to Section 4(a) shall be conditioned upon such Holder's participation
in such underwriting and the inclusion of such Holder's Registrable Securities
in the underwriting to the extent provided herein. All Holders proposing to
distribute their securities through such underwriting shall (together with the
Company and any other shareholders of the Company distributing their securities
through such underwriting) enter into an underwriting agreement in customary
form with the underwriter or underwriters selected for such underwriting by the
Company. Notwithstanding any other provision of this Section 4(b), if the
underwriter or the Company determines that marketing factors require a
limitation of the number of shares to be underwritten, the underwriter may
exclude some or all Registrable Securities from such registration and
underwriting. The Company shall so advise all Holders (except those Holders who
have indicated to the Company their decision not to distribute any of their
Registrable Securities through such underwriting), and the number of shares of
Registrable Securities that may be included in the registration and
underwriting, if any, shall be allocated among such Holders as follows:

                  (i)      In the event of a piggyback registration pursuant to
Section 4(a) that is initiated by the Company, then the number of shares that
may be included in the registration and underwriting shall be allocated first
to the Company and then to all selling shareholders, including the Holders, who
have requested to sell in the registration on a pro rata basis according to the
number of shares requested to be included; provided, however, that no
allocation pursuant to this Section 4(b) shall have the effect of reducing the
Shares sold by Holders to less than 20% of the proposed offering; and

                  (ii)     In the event of a piggyback registration pursuant to
Section 4(a) that is initiated by the exercise of demand registration rights by
a shareholder or shareholders of the Company (other than the Holders), then the
number of shares that may be included in the registration and underwriting
shall be allocated first to such selling shareholders who exercised such demand
and then to all selling


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shareholders, including the Holders, who have requested to sell in the
registration, on a pro rata basis according to the number of shares requested
to be included.


         (c)      No Registrable Securities excluded from the underwriting by
reason of the underwriter's marketing limitation shall be included in such
registration. If any Holder disapproves of the terms of any such underwriting,
such person may elect to withdraw therefrom by written notice to the Company
and the underwriter. The Registrable Securities and/or other securities so
withdrawn from such underwriting shall also be withdrawn from such
registration; provided, however, that, if by the withdrawal of such Registrable
Securities a greater number of Registrable Securities held by other Holders may
be included in such registration (up to the maximum of any limitation imposed
by the underwriters), then the Company shall offer to all Holders who have
included Registrable Securities in the registration the right to include
additional Registrable Securities pursuant to the terms and limitations set
forth herein in the same proportion used above in determining the underwriter
limitation.

         5.       Registration Procedures. In the case of each registration,
qualification or compliance effected by the Company pursuant to Section 2, 3 or
4 hereof, the Company will keep each Holder advised in writing as to the
initiation of each registration, qualification and compliance and as to the
completion thereof. At its expense, the Company will use its reasonable best
efforts to:

         (a)      prepare and file with the Commission within ninety (90) days
(or in the case of any registration on Form S-3, thirty (30) days) after
receipt of a request for registration with respect to such Registrable
Securities, a registration statement on any form for which the Company then
qualifies or which counsel for the Company shall deem appropriate, subject to
Section 2 hereof, and which form shall be available for the sale of the
Registrable Securities in accordance with the intended method(s) of
distribution thereof, and use its best efforts to cause such registration
statement to become and remain effective; provided that before filing with the
Commission a registration statement or prospectus or any amendments or
supplements thereto, including documents incorporated by reference after the
initial filing of any registration statement, the Company shall (i) furnish to
the underwriters, if any, and to one (1) counsel selected by the Holders of a
majority of the Registrable Securities covered by such registration statement
copies of all such documents proposed to be filed, which documents shall be
subject to the review of the underwriters and such counsel, and (ii) notify
each Holder of Registrable Securities covered by such registration statement of
any stop order issued or threatened by the Commission and take all reasonable
actions required to prevent the entry of such stop order or to remove it if
entered;

         (b)      prepare and file with the Commission such amendments and
supplements to such registration statement and the prospectus used in
connection therewith as may be necessary to keep such registration statement
effective for a period of not less than ninety (90) days or such shorter period
which shall terminate when all Registrable Securities covered by such
registration statement have been sold (but not before the expiration of the
90-day period referred to in Section 4(3) of the Securities Act and Rule 174,
or any successor thereto, thereunder, if applicable), and comply with the
provisions of the Securities Act with respect to the disposition of all
securities covered by such registration statement during such period in
accordance with the intended method(s) of disposition by the sellers thereof
set forth in such registration statement;

         (c)      furnish, without charge, to each Holder and each underwriter,
if any, of Registrable Securities covered by such registration statement one
(1) signed copy of such registration statement, each amendment and supplement
thereto (including one (1) conformed copy to each Holder and one (1)


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signed copy to each managing underwriter and in each case including all
exhibits thereto), and such number of copies of the prospectus included in such
registration statement (including each preliminary prospectus and any other
prospectus filed under Rule 424 under the Securities Act) as such Holders may
request, in conformity with the requirements of the Securities Act, and such
other documents as such Holder may reasonably request in order to facilitate
the disposition of the Registrable Securities owned by such Holder, but only
while the Company shall be required under the provisions hereof to cause the
registration statement to remain effective;

         (d)      use its best efforts to register or qualify such Registrable
Securities under such other applicable securities or blue sky laws of such
jurisdictions as any Holder, and underwriter, if any, of Registrable Securities
covered by such registration statement reasonably requests as may be necessary
for the marketability of the Registrable Securities (such request to be made by
the time the applicable registration statement is deemed effective by the
Commission) and do any and all other acts and things which may be reasonably
necessary or advisable to enable such Holder and each underwriter, if any, to
consummate the disposition in such jurisdictions of the Registrable Securities
owned by such Holder; provided that the Company shall not be required to (i)
qualify generally to do business in any jurisdiction where it would not
otherwise be required to qualify but for this paragraph (d), (ii) subject
itself to taxation in any such jurisdiction, or (iii) consent to general
service of process in any such jurisdiction;

         (e)      use its best efforts to cause the Registrable Securities
covered by such registration statement to be registered with or approved by
such other governmental agencies or authorities as may be necessary by virtue
of the business and operations of the Company to enable the Holder or Holders
thereof to consummate the disposition of such Registrable Securities;

         (f)      immediately notify the managing underwriter, if any, and each
Holder of such Registrable Securities at any time when a prospectus relating
thereto is required to be delivered under the Securities Act of the happening
of any event which comes to the Company's attention if as a result of such
event the prospectus included in such registration statement contains an untrue
statement of a material fact or omits to state any material fact required to be
stated therein or necessary to make the statements therein not misleading and
the Company shall promptly prepare and furnish to such Holder a supplement or
amendment to such prospectus so that, as thereafter delivered to the purchasers
of such Registrable Securities, such prospectus shall not contain an untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary to make the statements therein not misleading,
unless suspension of the use of such prospectus otherwise is authorized herein
or in the event of a S-3 Blackout Period, in which case no supplement or
amendment need be furnished;

         (g)      use its best efforts to cause all such Registrable Securities
covered by the registration statement to be listed on the Nasdaq Stock Market
or the national securities exchange on which similar securities issued by the
Company are then listed, and enter into such customary agreements including a
listing application and indemnification agreement in customary form (provided
that the applicable listing requirements are satisfied), and to provide a
transfer agent and registrar for such Registrable Securities covered by such
registration statement no later than the effective date of such registration
statement;

         (h)      enter into such customary agreements (including an
underwriting agreement in customary form) and take all such other actions as
the Initiating Holders or the underwriters retained by such Holders, if any,
reasonably request in order to expedite or facilitate the disposition of such
Registrable Securities, including customary indemnification;


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         (i)      make available for inspection during normal business hours by
any Holder of Registrable Securities covered by such registration statement,
any underwriter participating in any disposition pursuant to such registration
statement, and any attorney, accountant or other agent retained by any such
Holder or underwriter (collectively, the "Inspectors"), all financial and other
records, pertinent corporate documents and properties of the Company and its
subsidiaries (collectively, "Records"), if any, as shall be reasonably
necessary to enable them to exercise their due diligence responsibility, and
cause the Company's and its subsidiaries' officers, directors and employees to
supply all information and respond to all inquiries reasonably requested by any
such Inspector in connection with such registration statement. Notwithstanding
the foregoing, the Company shall have no obligation to disclose any Records to
the Inspectors in the event the Company determines that such disclosure is
reasonably likely to have an adverse effect on the Company's ability to assert
the existence of an attorney-client privilege with respect thereto;

         (j)      in the event that any contemplated public offering is
underwritten, use its best efforts to obtain a "comfort" letter from the
Company's independent public accountants in customary form and covering such
matters of the type customarily covered by "comfort" letters as the Holders of
a majority (by number of shares) of the Registrable Securities being sold
reasonably request, and provided that such request is reasonable in the
underwriter's point of view;

         (k)      use its best efforts to obtain an obtain an opinion of
counsel from the Company's counsel in customary form and covering such matters
of the type customarily covered in opinions of counsel in connection with such
transactions;

         (l)      comply, and continue to comply during the period that such
registration statement is effective under the Securities Act, in all material
respects with the Securities Act and the Securities Exchange Act of 1934 and
with all applicable rules and regulations of the Commission with respect to the
disposition of all securities covered by such registration statement, and make
available to its security holders, as soon as reasonably practicable, an
earnings statement covering the period of at least twelve (12) months, but not
more than eighteen (18) months, beginning with the first full calendar month
after the effective date of such registration statement, which earnings
statement shall satisfy the provisions of Section 11(a) of the Securities Act,
and not file any amendment or supplement to such registration statement or
prospectus to which Holder shall have reasonably objected on the grounds that
such amendment or supplement does not comply in all material respects with the
requirements of the Securities Act, having been furnished with a copy thereof
at least five (5) business days prior to the filing thereof; and

         (m)      in the event the offering is underwritten, develop a
presentation reasonably acceptable to the underwriters to facilitate the
offering and to make its chief executive officer and chief financial officer
available for participation in such meetings and presentations (e.g., road show
for the offering) at such locations (including Europe) as the underwriter
reasonably requests.

Each Holder of Registrable Securities agrees that, upon receipt of any notice
from the Company of the happening of any event of the kind described in Section
5(f) hereof, such Holder shall discontinue disposition of Registrable
Securities pursuant to the registration statement covering such Registrable
Securities until such Holder's receipt of the copies of the supplemented or
amended prospectus contemplated by Section 5(f) hereof, and, if so directed by
the Company, such Holder shall deliver to the Company (at the Company's
expense) all copies (including, without limitation, any and all drafts), other
than permanent file copies, then in such Holder's possession, of the prospectus
covering such Registrable Securities current at the time of receipt of such
notice. In the event the Company shall give


                                      10
<PAGE>   11


any such notice, the period mentioned in Section 5(b) hereof shall be extended
by the greater of (i) ten (10) business days or (ii) the number of days during
the period from and including the date of the giving of such notice pursuant to
Section 5(f) hereof to and including the date when each Holder of Registrable
Securities covered by such registration statement shall have received the
copies of the supplemented or amended prospectus contemplated by Section 5(f)
hereof.

         6.       Rule 144. Notwithstanding anything to the contrary contained
herein, no Holder shall have rights to a registration under Section 2, 3 or 4
hereof after the time that such Holder could sell, within ninety (90) days, all
of its Registrable Securities pursuant to Rule 144(e) promulgated under the
Securities Act or any successor rule thereto; provided that the Company hereby
agrees to take the following actions to ensure the availability of Rule 144 to
each such Holder (or such similar actions as shall be required under any
successor rule thereto):

         (a)      make and keep public information available as those terms are
understood and defined in Rule 144;

         (b)      use its best efforts to file with the Commission in a timely
manner all reports and other documents required of the Company under the
Securities Act and the Exchange Act; and

         (c)      so long as any Holder owns any Registrable Securities,
furnish to a Holder upon request, a written statement by the Company as to its
compliance with the reporting requirements of Rule 144 (at any time from and
after ninety (90) days following the effective date of the registration
statement relating to an Initial Public Offering), and of the Securities Act
and the Exchange Act (at any time after it has become subject to such reporting
requirements), a copy of the most recent annual or quarterly report of the
Company, and such other reports and documents so filed as the Holder may
reasonably request.

         7.       Registration Expenses. The Company shall pay all expenses in
connection with any registration, including, without limitation, all
registration, filing and NASD fees, printing expenses, all fees and expenses of
complying with securities or blue sky laws, the fees and disbursements of one
counsel for the Holders and the fees and disbursements of counsel for the
Company and of its independent accountants; provided that, in any registration,
each party shall pay for its own underwriting discounts and commissions and
transfer taxes. The Company shall not, however, be required to pay for expenses
of any registration proceeding begun pursuant to Section 2, 3 or 4 hereof, the
request of which has been subsequently withdrawn by the Initiating Holders
(unless the withdrawal is based upon material adverse information concerning
the Company of which the Initiating Holders were unaware at the time of such
request), in which case such expenses shall be borne by the Holders whose
securities were to be included in the registration in proportion to the number
of shares for which such registration was requested.

         8.       Assignment of Rights. Any Holder may assign its rights under
this Agreement to any party acquiring 2,400,000 shares or more of Registrable
Securities; provided, however, that a Holder may assign its rights under this
Agreement without such restrictions to a transferee or assignee that controls,
is controlled by or is under common control with such Holder.

         9.       Information by Holder. The Holder or Holders of Registrable
Securities included in any registration shall furnish to the Company such
information regarding such Holder or Holders and the distribution proposed by
such Holder or Holders as the Company may request in writing.


                                      11
<PAGE>   12


         10.      "Market Stand-off" Agreement. Each Holder agrees not to sell
or otherwise transfer or dispose of any Common Stock (or other securities) of
the Company held by it during such period of time following the effective date
of an underwritten public offering of the Company's securities as the
underwriters in such underwritten offering deem appropriate; provided, however,
that no such market stand off agreement shall be required of any Holder (i) who
is not identified as a selling shareholder on the registration statement for
such underwritten offering or any other registration statement filed by the
Company pursuant to Sections 2, 3 or 4 hereof and (ii) unless the executive
officers, directors and greater than 10% stockholders of the Company enter into
similar agreements; provided, however, that in no event shall such period be
more than 90 days. The Company may impose stop-transfer instructions with
respect to the shares (or securities) subject to the foregoing restriction
until the end of such period.

         11.      Indemnification.

         (a)      In the event of the offer and sale of Registrable Securities
held by Holders under the 1933 Act, the Company shall, and hereby does,
indemnify and hold harmless, to the fullest extent permitted by law, each
Holder, its directors, officers, partners, each other person who participates
as an underwriter in the offering or sale of such securities, and each other
Person, if any, who controls or is under common control with such Holder or any
such underwriter within the meaning of Section 15 of the 1933 Act, against any
losses, claims, damages or liabilities, joint or several, and expenses to which
the Holder or any such director, officer, partner or underwriter or controlling
person may become subject under the 1933 Act or otherwise, insofar as such
losses, claims, damages, liabilities or expenses (or actions or proceedings,
whether commenced or threatened, in respect thereof) arise out of or are based
upon any untrue statement or alleged untrue statement of any material fact
contained in any registration statement under which such shares were registered
under the 1933 Act, any preliminary prospectus, final prospectus or summary
prospectus contained therein, or any amendment or supplement thereto, or any
omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein in light of the
circumstances in which they were made not misleading or any violation by the
Company of any federal, state or common law rule or regulation applicable to
the Company and relating to action required of or inaction by the Company in
connection with any such registration, and the Company shall reimburse the
Holder, and each such director, officer, partner, underwriter and controlling
person for any legal or any other expenses reasonably incurred by them in
connection with investigating, defending or settling any such loss, claim,
damage, liability, action or proceeding; provided that the Company shall not be
liable in any such case to the extent that any such loss, claim, damage,
liability (or action or proceeding in respect thereof) or expense arises out of
or is based upon an untrue statement or alleged untrue statement in or omission
or alleged omission from such registration statement, any such preliminary
prospectus, final prospectus, summary prospectus, amendment or supplement in
reliance upon and in conformity with written information furnished to the
Company through an instrument duly executed by or on behalf of such Holder
specifically stating that it is for use in the preparation thereof. Such
indemnity shall remain in full force and effect regardless of any investigation
made by or on behalf of the Holders, or any such director, officer, partner,
underwriter or controlling person and shall survive the transfer of such shares
by the Holder.

         (b)      The Company may require, as a condition to including any
Registrable Securities to be offered by a Holder in any registration statement
filed pursuant to this Agreement, that the Company shall have received an
agreement from such Holder to be bound by the terms of this Section 11,
including an undertaking reasonably satisfactory to it from such Holder, to
indemnify and hold the


                                      12
<PAGE>   13


Company, its directors and officers and each other Person, if any, who controls
the Company within the meaning of Section 15 of the 1933 Act, against any
losses, claims, damages or liabilities, joint or several, to which the Company
or any such director or officer or controlling person may become subject under
the 1933 Act or otherwise, insofar as such losses, claims, damages or
liabilities (or actions or proceedings, whether commenced or threatened, in
respect thereof) arise out of or are based upon any untrue statement or alleged
untrue statement in or omission or alleged omission from such registration
statement, any preliminary prospectus, final prospectus or summary prospectus
contained therein, or any amendment or supplement thereto, if such statement or
alleged statement or omission or alleged omission was made in reliance upon and
in conformity with written information about such Holder as a Holder of the
Company furnished to the Company through an instrument duly executed by such
Holder specifically stating that it is for use in the preparation of such
registration statement, preliminary prospectus, final prospectus, summary
prospectus, amendment or supplement; provided, however, that such indemnity
agreement found in this Section 11(b) shall in no event exceed the gross
proceeds from the offering received by such Holder. Such indemnity shall remain
in full force and effect, regardless of any investigation made by or on behalf
of the Company or any such director, officer or controlling person and shall
survive the transfer by any Holder of such shares.

         (c)      Promptly after receipt by an indemnified party of notice of
the commencement of any action or proceeding involving a claim referred to in
Section 11(a) or (b) hereof (including any governmental action), such
indemnified party shall, if a claim in respect thereof is to be made against an
indemnifying party, give written notice to the indemnifying party of the
commencement of such action; provided that the failure of any indemnified party
to give notice as provided herein shall not relieve the indemnifying party of
its obligations under Section 11(a) or (b) hereof, except to the extent that
the indemnifying party is actually prejudiced by such failure to give notice.
In case any such action is brought against an indemnified party, unless in such
indemnified party's reasonable judgment a conflict of interest between such
indemnified and indemnifying parties may exist or the indemnified party may
have defenses not available to the indemnifying party in respect of such claim,
the indemnifying party shall be entitled to participate in and to assume the
defense thereof, with counsel reasonably satisfactory to such indemnified party
and, after notice from the indemnifying party to such indemnified party of its
election so to assume the defense thereof, the indemnifying party shall not be
liable to such indemnified party for any legal or other expenses subsequently
incurred by the latter in connection with the defense thereof, unless in such
indemnified party's reasonable judgment a conflict of interest between such
indemnified and indemnifying parties arises in respect of such claim after the
assumption of the defenses thereof, other than reasonable costs of
investigation. Neither an indemnified nor an indemnifying party shall be liable
for any settlement of any action or proceeding effected without its consent. No
indemnifying party shall, without the consent of the indemnified party, consent
to entry of any judgment or enter into any settlement which does not include as
an unconditional term thereof the giving by the claimant or plaintiff to such
indemnified party of a release from all liability in respect of such claim or
litigation. Notwithstanding anything to the contrary set forth herein, and
without limiting any of the rights set forth above, in any event any party
shall have the right to retain, at its own expense, counsel with respect to the
defense of a claim.

         (d)      The indemnification required by Section 11(a) and (b) hereof
shall be made by periodic payments of the amount thereof during the course of
the investigation or defense, as and when bills are received or expenses,
losses, damages or liabilities are incurred.

         (e)      If the indemnification provided for in this Section 11 is
held by a court of competent jurisdiction to be unavailable to an indemnified
party with respect to any loss, liability, claim, damage or expense referred to
herein, the indemnifying party, in lieu of indemnifying such indemnified party


                                      13
<PAGE>   14


hereunder, shall contribute to the amount paid or payable by such indemnified
party as a result of such loss, liability, claim, damage or expense as is
appropriate to reflect the proportionate relative fault of the indemnifying
party on the one hand and the indemnified party on the other (determined by
reference to, among other things, whether the untrue or alleged untrue
statement of a material fact or omission relates to information supplied by the
indemnifying party or the indemnified party and the parties' relative intent,
knowledge, access to information and opportunity to correct or prevent such
untrue statement or omission), or (ii) if the allocation provided by clause (i)
above is not permitted by applicable law or provides a lesser sum to the
indemnified party than the amount hereinafter calculated, not only the
proportionate relative fault of the indemnifying party and the indemnified
party, but also the relative benefits received by the indemnifying party on the
one hand and the indemnified party on the other, as well as any other relevant
equitable considerations. No indemnified party guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the Securities Act)
shall be entitled to contribution from any indemnifying party who was not
guilty of such fraudulent misrepresentation.

         (f)      Other Indemnification. Indemnification similar to that
specified in the preceding subsections of this Section 11 (with appropriate
modifications) shall be given by the Company and each Holder of Registrable
Securities with respect to any required registration or other qualification of
securities under any federal or state law or regulation or governmental
authority other than the Securities Act.

         12.      Miscellaneous

         (a)      Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of the State of Delaware.

         (b)      Successors and Assigns. Except as otherwise provided herein,
the provisions hereof shall inure to the benefit of, and be binding upon, the
successors, assigns, executors and administrators of the parties hereto. In the
event the Company merges with, or is otherwise acquired by, a direct or
indirect subsidiary of a publicly-traded company, the Company shall condition
the merger or acquisition on the assumption by such parent company of the
Company's obligations under this Agreement.

         (c)      Entire Agreement. This Agreement constitutes the full and
entire understanding and agreement between the parties with regard to the
subjects hereof.

         (d)      Notices, etc. All notices or other communications which are
required or permitted under the Transaction Documents shall be in writing and
sufficient if delivered by hand, by facsimile transmission, by registered or
certified mail, postage pre-paid, or by courier or overnight carrier, to the
persons at the addresses set forth below (or at such other address as may be
provided hereunder), and shall be deemed to have been delivered as of the date
so delivered:


                                      14
<PAGE>   15


         If to the Company:       Healtheon/WebMD Corporation
                                  400 The Lenox Building
                                  3399 Peachtree Road
                                  Atlanta, Georgia 30326
                                  Attention: W. Michael Heekin, Esq.

                                  Healtheon/WebMD Corporation
                                  4600 Patrick Henry Road
                                  Santa Clara CA 95054
                                  Attention: Jack Dennison, Esq.

         With a copy to:          Nelson Mullins Riley & Scarborough, L.L.P.
                                  Bank of America Corporate Center
                                  Suite 2600
                                  100 North Tryon Street
                                  Charlotte, North Carolina 28202
                                  Attention: H. Bryan Ives III, Esq.
                                             C. Mark Kelly, Esq.

         If to Purchaser:         The News Corporation Limited
                                  1211 Avenue of the Americas
                                  New York, New York 10036
                                  Attention: Arthur M. Siskind, Esq.

         With a copy to:          Squadron, Ellenoff, Plesent & Sheinfeld, LLP
                                  551 Fifth Avenue
                                  New York, New York 10176
                                  Attention: Joel I. Papernik, Esq.

or at such other address as any party shall have furnished to the other parties
in writing.

         (e)      Delays or Omissions. No delay or omission to exercise any
right, power or remedy accruing to any Holder of any Registrable Securities,
upon any breach or default of the Company under this Agreement, shall impair
any such right, power or remedy of such Holder nor shall it be construed to be
a waiver of any such breach or default, or an acquiescence therein, or of or in
any similar breach or default thereunder occurring; nor shall any waiver of any
single breach or default be deemed a waiver of any other breach or default
theretofore or thereafter occurring. Any waiver, permit, consent or approval of
any kind or character on the part of any Holder of any breach or default under
this Agreement, or any waiver on the part of any Holder of any provisions or
conditions of this Agreement, must be in writing and shall be effective only to
the extent specifically set forth in such writing. All remedies, either under
this Agreement, or by law or otherwise afforded to any holder, shall be
cumulative and not alternative.

         (f)      Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be enforceable against the parties actually
executing such counterparts, and all of which together shall constitute one
instrument.


                                      15
<PAGE>   16


         (g)      Severability. In the case any provision of this Agreement
shall be invalid, illegal or unenforceable, the validity, legality and
enforceability of the remaining provisions shall not in any way be affected or
impaired thereby.

         (h)      Amendments. The provisions of this Agreement may be amended
at any time and from time to time, and particular provisions of this Agreement
may be waived, with and only with an agreement or consent in writing signed by
the Company and by the holders of a majority of the number of shares of
Registrable Securities outstanding as of the date of such amendment or waiver.
The Purchaser acknowledges that by the operation of this Section 12(h), the
holders of a majority of the outstanding Registrable Securities may have the
right and power to diminish or eliminate all rights of the Purchaser under this
Agreement.


                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]


                                      16
<PAGE>   17


This Registration Rights Agreement is hereby executed as of the date first
above written.



                                 COMPANY:


                                 HEALTHEON/WEBMD CORPORATION


                                 By:   /s/
                                    -------------------------------------------
                                    Its:  W. Michael Heekin
                                          Exec. Vice President


                                 PURCHASERS:


                                 EASTRISE PROFITS LIMITED


                                 By:   /s/
                                    -------------------------------------------
                                    Its:  Lawrence A. Jacobs
                                          Director


                                 AHN/FIT CABLE, LLC


                                 By:   /s/
                                    -------------------------------------------
                                    Its:  Daniel Fawcett
                                          Exec. Vice President


                                 AHN/FIT INTERNET, LLC


                                 By:   /s/
                                    -------------------------------------------
                                    Its:  Daniel Fawcett
                                          Exec. Vice President


                                 NEWS AMERICA INCORPORATED


                                 By:   /s/
                                    -------------------------------------------
                                    Its:   Lawrence A. Jacobs
                                           Sr. Vice President


                                 FOX BROADCASTING COMPANY


                                 By:   /s/
                                    -------------------------------------------
                                    Its:   Paul Haggerty
                                           Exec. Vice President


                                      17