<PAGE>

                          REGISTRATION RIGHTS AGREEMENT

         THIS REGISTRATION RIGHTS AGREEMENT is made as of the ____ day of
February, 1999, by and between HealthDesk Corporation, a California corporation
(the "Company"), and each other person or entity executing this Agreement.

                                    RECITALS

         WHEREAS, the Company has issued shares of its common stock, no par
value (the "Common Stock") to certain investors (the "Investors") pursuant to
the terms of the Agreement and Plan of Reorganization by and among the Company,
MC Acquisition Corporation, a California corporation and a wholly-owned
subsidiary of the Company, MC Informatics, Inc., a California corporation
("MCI") and certain shareholders of MCI (the "Merger");

         WHEREAS, the Company and the Investors desire to provide for certain
arrangements with respect to the registration of shares of Common Stock of the
Company under the Securities Act of 1933, as amended (the "Securities Act"),
held by the Investors as provided in this Agreement;

         NOW, THEREFORE, in consideration of the mutual promises and agreements
contained herein and for other good and valuable consideration the receipt and
sufficiency of which are hereby acknowledged, the Company and the Investors
hereby agree as follows:

                                    AGREEMENT

         1. Registration Rights. The Company covenants and agrees as follows:

            1.1. Definitions. For purposes of this Paragraph 1:

                 (a) The term "register," and "registered," and "registration"
refer to a registration effected by preparing and filing a registration
statement or similar document in compliance with the Securities Act and the
declaration or ordering of effectiveness of such registration statement or
document;

                 (b) The term "Registrable Securities" means (1) the shares of
Common Stock issued to the Investors in connection with the Merger and (2) any
Common Stock of the Company issued as (or issuable upon the conversion or
exercise of any warrant, right or other security which is issued as) a dividend
or other distribution with respect to, or in exchange for or in replacement of,
such Common Stock, excluding in all cases, however, any Registrable Securities
sold by a person in a transaction in which his rights under this Section 1 are
not assigned or pursuant to an effective registration statement or to the public
pursuant to an exemption from registration requirements under the Securities
Act;



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                 (c) The number of shares of "Registrable Securities then
outstanding" shall be determined by the number of shares of Common Stock
outstanding which are Registrable Securities; and

                 (d) The term "Holder" means any person owning or having the
right to acquire Registrable Securities or any assignee thereof in accordance
with Section 1.12 hereof.

            1.2. Request for Registration.

                 (a) If the Company shall receive at any time after the date of
this Agreement and prior to the one year anniversary of this Agreement, a
written request from the Holders of more than fifty percent (50%) of the
Registrable Securities then outstanding that the Company file a registration
statement under the Securities Act covering the registration of at least fifty
percent (50%) of the Registrable Securities then outstanding, then the Company
shall promptly give written notice of such request to all Holders and shall,
subject to the limitations of subsection 1.2(b), effect as soon as practicable
the registration under the Securities Act of all Registrable Securities which
the Holders request to be registered within thirty (30) days of the mailing of
such notice by the Company in accordance with Section 2.5.

                 (b) If the Holders initiating the registration request
hereunder ("Initiating Holders") intend to distribute the Registrable Securities
covered by their request by means of an underwriting, they shall so advise the
Company as a part of their request made pursuant to this Section 1.2 and the
Company shall include such information in the written notice referred to in
subsection 1.2(a). The underwriter will be selected by a majority in interest of
the Initiating Holders and approved by the Company, which approval shall not
unreasonably be withheld. In such event, the right of any Holder to include his
Registrable Securities in such registration shall be conditioned upon such
Holder's participation in such underwriting to the extent provided herein. All
Holders proposing to distribute their securities through such underwriting shall
(together with the Company as provided in subsection 1.4(e)) enter into an
underwriting agreement in customary form with the underwriter or underwriters
selected for such underwriting by a majority in interest of the Initiating
Holders. Notwithstanding any other provision of this Section 1.2, if the
underwriter advises the Initiating Holders in writing that marketing factors
require a limitation of the number of shares to be underwritten, then the
Initiating Holder shall so advise all Holders of Registrable Securities that may
be included in the underwriting that such number of Registrable Securities to be
included shall be allocated among all such Holders thereof, including the
Initiating Holders, in proportion (as nearly as practicable) to the amount of
Registrable Securities of the Company owned by each Holder; provided, however,
that the number of shares of Registrable Securities to be included in such
underwriting shall not be reduced unless all other securities are first entirely
excluded from the underwriting.

                 (c) The Company is obligated to effect only one (1) such
registration pursuant to this Section 1.2.

                 (d) Notwithstanding the foregoing, if the Company shall furnish
to Holders requesting a registration statement pursuant to this Section 1.2 a
certificate signed by the President of the Company stating that in the good
faith judgment of the Board of Directors of the



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<PAGE>



Company it would be seriously detrimental to the Company and its shareholders 
for such registration statement to be filed and it is therefore essential to
defer the filing of such registration statement, the Company shall have the
right to defer taking action with respect to such filing for a period of not
more than sixty (60) days after receipt of the request of the Initiating 
Holders; provided, however, that the Company may not utilize this right more
than once in any twelve month period.

            1.3. Company Registration.

                 (a) If (but without any obligation to do so) at any time after
February 26, 2000, and prior to February 26, 2001, the Company proposes to
register (including for this purpose a registration effected by the Company for
shareholders other than the Holders) any of its stock or other securities under
the Securities Act in connection with the public offering of such securities
solely for cash (other than a registration relating solely to the sale of
securities to participants in a Company stock plan, or a registration on any
form which does not include substantially the same information as would be
required to be included in a registration statement covering the sale of the
Registrable Securities), the Company shall, at such time, promptly give each
Holder written notice of such registration. Upon the written request of each
Holder given within thirty (30) days after mailing of such notice by the Company
in accordance with Section 2.5, the Company shall, subject to the provisions of
Section 1.8, cause to be registered under the Securities Act all of the
Registrable Securities that each such Holder has requested to be registered.

                 (b) The Company is obligated to effect only two (2) such
registrations pursuant to this Section 1.3.

            1.4. Obligations of the Company. Whenever required under this
Paragraph 1 to effect the registration of any Registrable Securities, the
Company shall, as expeditiously as reasonably possible:

                 (a) Prepare and file with the SEC a registration statement with
respect to such Registrable Securities and use its best efforts to cause such
registration statement to become effective and, upon the request of the Holders
of a majority of the Registrable Securities registered thereunder, keep such
registration statement effective for up to one hundred twenty (120) days for the
purpose of selling all stock or securities registered with the SEC.

                 (b) Prepare and file with the SEC such amendments and
supplements to such registration statement and the prospectus used in connection
with such registration statement as may be necessary to comply with the
provisions of the Securities Act with respect to the disposition of all
securities covered by such registration statement.

                 (c) Furnish to the Holders such numbers of copies of a
prospectus, including a preliminary prospectus, in conformity with the
requirements of the Securities Act, and such other documents as they may
reasonably request in order to facilitate the disposition of Registrable
Securities owned by them.


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<PAGE>

                 (d) Use its best efforts to register and qualify the securities
covered by such registration statement under such other securities or Blue Sky
laws of such jurisdictions as shall be reasonably requested by the Holders,
provided that the Company shall not be required in connection therewith or as a
condition thereto to qualify to do business or to file a general consent to
service of process in any such states or jurisdictions.

                 (e) In the event of any underwritten public offering, enter
into and perform its obligations under an underwriting agreement, in usual and
customary form, with the managing underwriter or such offering. Each Holder
participating in such underwriting shall also enter into and perform its
obligations under such an agreement.

                 (f) Notify each Holder of Registrable Securities covered by
such registration statement at any time when a prospectus relating thereto is
required to be delivered under the Securities Act of the happening of any event
as a result of which the prospectus included in such registration statement, as
then in effect, includes an untrue statement of a material fact or omits to
state a material fact required to be stated therein or necessary to make the
statements therein not misleading in the light of the circumstances then
existing.

                 (g) Furnish, at the request of any Holder requesting
registration of Registrable Securities pursuant to this Paragraph 1, on the date
that such Registrable Securities are delivered to the underwriters for sale in
connection with a registration pursuant to this Paragraph 1 if such securities
are being sold through underwriters, or, if such securities are not being sold
through underwriters on the date that the registration statement with respect to
such securities becomes effective, (i) an opinion dated such date of the counsel
representing the Company for the purposes of such registration, in form and
substance as is customarily given to underwriters in an underwritten public
offering, addressed to the underwriters, if any, and to the Holders requesting
registration of Registrable Securities and (ii) a "cold comfort" letter dated
such date from the independent certified public accountants of the Company, in
form and substance as is customarily given by independent certified public
accountants to underwriters in an underwritten public offering, addressed to the
underwriters, if any, and to the Holders requesting registration of Registrable
Securities.

            1.5. Furnish Information.

                 (a) It shall be a condition precedent to the obligations of the
Company to take any action pursuant to this Section 1 with respect to the
Registrable Securities of any selling Holder that such Holder shall furnish to
the Company such information regarding itself, the Registrable Securities held
by it, and the intended method of disposition of such securities as shall be
required to effect the registration of such Holder's Registrable Securities.

                 (b) The Company shall have no obligation with respect to any
registration requested pursuant to Section 1.2 if, due to the operation of
subsection 1.5(a), the number of shares or the anticipated aggregate offering
price of the Registrable Securities to be included in the registration does not
equal or exceed the number of shares or the anticipated aggregate offering price
required to originally trigger the Company's obligation to initiate such
registration as specified in subsection 1.2(a).


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<PAGE>

            1.6. Expenses of Demand Registration. All expenses other than
underwriting discounts and commissions incurred in connection with
registrations, filings, or qualifications pursuant to Section 1.2, including
without limitation all registration, filing and qualification fees, printers'
and accounting fees, fees and disbursements of counsel for the Company, and the
reasonable fees and disbursements of one counsel for the selling Holders shall
be borne by the Company; provided, however, that the Company shall not be
required to pay for any expenses of any registration proceeding begun pursuant
to Section 1.2 if the registration request is subsequently withdrawn at the
request of the Holders of a majority of the Registrable Securities to be
registered (in which case all Participating Holders shall bear such expenses),
unless the Holders of a majority of the Registrable Securities agree to forfeit
their right to demand registration pursuant to Section 1.2; provided further,
however, that if at the time of such withdrawal, the Holders have learned of a
material adverse change in the condition, business, or prospects of the Company
from that known to the Holders at the time of their request and have withdrawn
the request with reasonable promptness following disclosure by the Company of
such material adverse change, then the Holders shall not be required to pay any
of such expenses and shall retain their rights pursuant to Section 1.2. Fees and
disbursements of counsel and accountants for the selling Holders and any other
expenses incurred by the selling Holders not expressly included above shall be
borne by the selling Holders.

            1.7. Expenses of Company Registration. The Company shall bear and
pay all expenses incurred in connection with any registration, filing or
qualification of Registrable Securities with respect to all registrations
pursuant to Section 1.3 for each Holder (which right may be assigned as provided
in Section 1.12), including, without limitation, all registration, filing, and
qualification fees, printers and accounting fees relating or apportionable
thereto and the fees and disbursements of one counsel for the selling Holders
selected by them, but excluding underwriting discounts and commissions relating
to Registrable Securities.

            1.8. Underwriting Requirements. In connection with any offering
involving an underwriting of shares of the Company's capital stock, the Company
shall not be required under Section 1.3 to include any of the Holders'
securities in such underwriting unless they accept the terms of the underwriting
as agreed upon between the Company and the underwriters selected by it (or by
other persons entitled to select the underwriters), and then only in such
quantity as the underwriters determine in their sole discretion will not
jeopardize the success of the offering by the Company. If the total amount of
securities, including Registrable Securities, requested by shareholders to be
included in such offering exceeds the amount of securities sold other than by
the Company that the underwriters determine in their sole discretion is
compatible with the success of the offering, then the Company shall be required
to include in the offering only that number of such securities, including
Registrable Securities, which the underwriters determine in their sole
discretion will not jeopardize the success of the offering (the securities so
included to be apportioned pro rata among the selling shareholders according to
the total amount of securities entitled to be included therein owned by each
selling shareholder or in such other proportions as shall mutually be agreed to
by such selling shareholders) but in no event shall (i) the amount of
securities, including Registrable Securities and all other securities the
holders of which have similar rights, of the selling shareholders included in
the offering be reduced below thirty percent (30%) of the total amount of
securities included in such offering, or (ii) notwithstanding (i) above, any
shares being sold by a shareholder exercising a demand registration right
similar to that granted in Section 1.2 be excluded from such offering. For
purposes of the preceding parenthetical concerning apportionment of any selling
shareholder which is a holder of Registrable Securities and which is a
partnership or corporation, the partners, retired partners and shareholders of
such holder, or the estates and family members of any such partners and retired
partners and any trusts for the benefit of any of the foregoing persons shall be
deemed to be a single "selling shareholder," and any pro-rata reduction with
respect to such "selling shareholder" shall be based upon the aggregate amount
of shares carrying registration rights owned by all entities and individuals
included in such "selling shareholder," as defined in this sentence.


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<PAGE>

            1.9. Delay of Registration. No Holder shall have any right to obtain
or seek any injunction restraining or otherwise delaying any such registration
as a result of any controversy that might arise with respect to the
interpretation or implementation of this Paragraph 1.

            1.10. Indemnification. In the event any Registrable Securities are
included in a registration statement under this Paragraph 1:

                  (a) To the extent permitted by law, the Company will indemnify
and hold harmless each Holder, any underwriter (as defined in the Securities
Act) for such Holder and each person, if any, who controls such Holder or
underwriter within the meaning of the Securities Act or the Securities and
Exchange Act of 1934, as amended (the "1934 Act"), against any losses, claims,
damages, or liabilities (joint or several) to which they may become subject
under the Securities Act, or the 1934 Act or other federal or state law, insofar
as such losses, claims, damages, or liabilities (or actions in respect thereof)
arise out of or are based upon any of the following statements, omissions or
violations (collectively, a "Violation"): (i) any untrue statement or alleged
untrue statement of a material fact contained in such registration statement,
including any preliminary prospectus or final prospectus contained therein or
any amendments or supplements thereto, (ii) the omission or alleged omission to
state therein a material fact required to be stated therein, or necessary to
make the statements therein not misleading, or (iii) any violation or alleged
violation by the Company of the Securities Act, the 1934 Act, any state
securities law or any rule or regulation promulgated under the Securities Act,
or the 1934 Act or any state securities law; and the Company will pay to each
such Holder, underwriter or controlling person, as incurred, any legal or other
expenses reasonably incurred by them in connection with investigating or
defending any such loss, claim, damage, liability or action; provided, however,
that the indemnity agreement contained in this subsection 1.10(a) shall not
apply to amounts paid in settlement of any such loss, claim, damage, liability,
or action if such settlement is effected without the consent of the Company
(which consent shall not be unreasonably withheld), nor shall the Company be
liable in any such case for any such loss, claim, damage, liability, or action
to the extent that it arises out of or is based upon a Violation which occurs in
reliance upon and in conformity with written information furnished expressly for
use in connection with such registration by any such Holder, underwriter or
controlling person.


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<PAGE>

                  (b) To the extent permitted by law, each selling Holder will
indemnify and hold harmless the Company, each of its directors, each of its
officers who has signed the registration statement, each person, if any, who
controls the Company within the meaning of the Securities Act, any underwriter,
any other Holder selling securities in such registration statement and any
controlling person of any such underwriter or other Holder, against any losses,
claims, damages, or liabilities (joint or several) to which any of the foregoing
persons may become subject, under the Securities Act, or the 1934 Act or other
federal or state law, insofar as such losses, claims, damages, or liabilities
(or actions in respect thereto) arise out of or are based upon and in conformity
with written information furnished by such Holder for use in connection with
such registration; and each such Holder will pay, as incurred, any legal or
other expenses reasonably incurred by any person intended to be indemnified
pursuant to this subsection 1.10(b), in connection with investigating or
defending any such loss, claim, damage, liability, or action; provided, however,
that the indemnity agreement contained in this subsection 1.10(b) shall not
apply to amounts paid in settlement of any such loss, claim, damage, liability
or action if such settlement is effected without the consent of the Holder,
which consent shall not be unreasonably withheld; provided that in no event
shall any indemnity under this subsection 1.10(b) exceed the gross proceeds from
the offering received by such Holder.

                  (c) Promptly after receipt by an indemnified party under this
Section 1.10 of notice of the commencement of any action (including any
governmental action), such indemnified party will, if a claim in respect thereof
is to be made against any indemnifying party under this Section 1.10, deliver to
the indemnifying party a written notice of the commencement thereof and the
indemnifying party shall have the right to participate in, and, to the extent
the indemnifying party so desires, jointly with any other indemnifying party
similarly noticed, assume the defense thereof with counsel mutually satisfactory
to the parties; provided, however, that an indemnified party (together with all
other indemnified parties which may be represented without conflict by one
counsel) shall have the right to retain one separate counsel, with the fees and
expenses to be paid by the indemnifying party, if representation of such
indemnified party by the counsel retained by the indemnifying party would be
inappropriate due to actual or potential differing interests between such
indemnified parties. The failure to deliver written notice to the indemnifying
party within a reasonable time of the commencement of any such action, if
prejudicial to its ability to defend such action, shall relieve such
indemnifying party of any liability to the indemnified party under this Section
1.10, but the omission to deliver written notice to the indemnifying party will
not relieve it of any liability that it may have to any indemnified party
otherwise than under this Section 1.10.

                  (d) If the indemnification provided for in this Section 1.10
is held by a court of competent jurisdiction to be unavailable to an indemnified
party with respect to any loss, liability, claim, damage, or expenses referred
to therein, then the indemnifying party, in lieu of indemnifying such
indemnified party hereunder, shall contribute to the amount paid or payable by
such indemnified party as a result of such loss, liability, claim, damage, or
expense in such proportion as it appropriate to reflect the relative fault of
the indemnifying party on the one hand and of the indemnified party on the other
in connection with the statements or omissions that resulted in such loss,
liability, claim, damage, or expense as well as any other relevant equitable
considerations. The relative fault of the indemnifying party and of the
indemnified party shall be determined by reference to, among other things,
whether the untrue or alleged untrue statement of a material fact or the
omission to state a material fact relates to information supplied by the
indemnifying party or by the indemnified party and the parties' relative intent,
knowledge, access to information, and opportunity to correct or prevent such
statement or omission.


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                  (e) Notwithstanding the foregoing, to the extent that the
provisions on indemnification and contribution contained in the underwriting
agreement entered into in connection with the underwritten public offering are
in conflict with the foregoing provisions, the provisions in the underwriting
agreement shall control.

                  (f) The obligations of the Company and Holders under this
Section 1.10 shall survive the completion of any offering of Registrable
Securities in a registration statement under this Paragraph 1, and otherwise.

            1.11. Reports Under Securities Exchange Act of 1934. With a view to
making available to the Holders the benefits of Rule 144 promulgated under the
Securities Act and any other rule or regulation of the SEC that may at any time
permit a Holder to sell securities of the Company to the public without
registration, the Company agrees to:

                  (a) make and keep public information available, as those terms
are understood and defined in SEC Rule 144, at all times;

                  (b) file with the SEC in a timely manner all reports and other
documents required of the Company under the Securities Act and 1934 Act; and

                  (c) furnish to any Holder, so long as the Holder owns any
Registrable Securities, forthwith upon request (i) a written statement by the
Company that it has complied with the reporting requirements of SEC Rule 144,
the Securities Act and the 1934 Act, (ii) a copy of the most recent annual or
quarterly report of the Company and such other reports and documents so filed by
the Company, and (iii) such other information as may be reasonably requested in
availing any Holder of any rule or regulation of the SEC which permits the
selling of any such securities without registration.

            1.12. Assignment of Registration Rights. The rights to cause the
Company to register Registrable Securities pursuant to this Paragraph 1 may be
assigned (but only with all related obligations) by a Holder to a transferee or
assignee of such securities provided the Company is, within a reasonable time
after such transfer, furnished with written notice of the name and address of
such transferee or assignee and the securities with respect to which such
registration rights are being assigned; and provided, further, that such
assignment shall be effective only if immediately following such transfer the
further disposition of such securities by the transferee or assignee is
restricted under the Securities Act.

            1.13. Limitation on Subsequent Registration Rights. From and after
the date of this Agreement, the Company shall not, without the prior written
consent of the Holders of a majority of the outstanding Registrable Securities,
enter into any agreement with any holder or prospective holder of any securities
of the Company which would allow such holder or prospective holder to include
such securities in any registration filed under Section 1.2 hereof, unless under
the terms of such agreement, such holder or prospective holder may include such
securities in any such registration only to the extent that the inclusion of his
securities will not reduce the amount of the Registrable Securities of the
Holders which is included.

            1.14. Termination of Registration Rights. No Holder shall be
entitled to exercise any right provided for in this Section 1 after February 26,
2001.


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         2. Miscellaneous.

            2.1. Successors and Assigns. Except as otherwise provided herein,
the terms and conditions of this Agreement shall inure to the benefit of and be
binding upon the respective successors and assigns of the parties (including
transferees of the Registrable Securities). Nothing in this Agreement, express
or implied, is intended to confer upon any party other than the parties hereto
or their respective successors and assigns any rights, remedies, obligations, or
liabilities under or by reason of this Agreement, except as expressly provided
in this Agreement.

            2.2. Governing Law. This Agreement shall be governed by and
construed under the laws of the State of California without giving effect to
principles of conflicts of laws.

            2.3. Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

            2.4. Titles and Subtitles. The titles and subtitles used in this
Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement.

            2.5. Notices. Unless otherwise provided, any noticed required or
permitted under this Agreement shall be given in writing and shall be deemed
effectively given upon person delivery to the party to be notified or upon
deposit with the United States Post Office, by registered or certified mail,
postage prepaid and addressed to the party to be notified at the address
indicated for such party on the signature page hereto, or at such other address
as such party may designate by ten (10) days advance written notice to the other
parties.

            2.6. Amendments and Waivers. Any term of this Agreement may be
amended and the observance of any term of this Agreement may be waived (either
generally or in a particular instance and either retroactively or
prospectively), only with the written consent of the Company and the holders of
a majority of the Registrable Securities then outstanding. Any amendment or
waiver effected in accordance with this Section 2.6 shall be binding upon each
holder of any Registrable Securities then outstanding, each future holder of all
such Registrable Securities, and the Company.

            2.7. Severability. If one or more provisions of this Agreement are
held to be unenforceable under applicable law, such provision shall be excluded
from this Agreement and the balance of the Agreement shall be interpreted as if
such provision were so excluded and shall be enforceable in accordance with its
terms.


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            2.8. Aggregation of Stock. All shares of Registrable Securities held
or acquired by affiliated entities or persons shall be aggregated together for
the purpose of determining the availability of any rights under this Agreement.

            2.9. Entire Agreement. This Agreement (including the Exhibits
hereto, if any) constitutes the full and entire understanding and agreement
between the parties with regard to the subjects hereof and thereof.



                   Remainder of Page Intentionally Left Blank


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<PAGE>

         IN WITNESS WHEREOF, the parties have executed this Registration Rights
Agreement as of the date first above written.


HealthDesk Corporation
By:_____________________________________________________
      Terry Brandt, Vice President

Address:  c/o 2116 Financial Center
          Des Moines, Iowa 50309

INVESTOR:

________________________________________________________
[Type or Print Name]

By:_____________________________________________________

Print Title:____________________________________________

Address: _______________________________________________

         _______________________________________________

         _______________________________________________


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