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                                                                   EXHIBIT 10.12

                             CONVERTIBLE SECURITIES
                             SUBSCRIPTION AGREEMENT

         This Convertible Securities Subscription Agreement (this "Agreement"),
dated as of __________, 1998, has been executed by the undersigned (the
"Subscriber") in connection with (a) the sale of certain shares of Series B
Convertible Preferred Stock, no par value (the "Preferred Stock"), of HealthDesk
Corporation, a California corporation, having an address at 2560 9th Street,
Berkeley, California 94710 (the "Company"), convertible into shares of Common
Stock, no par value (the "Common Stock"), of the Company. The rights and
preferences of the Preferred Stock, including the terms on which the Preferred
Stock may be converted into Common Stock, are set forth in the Certificate of
Determination of the Series B Convertible Preferred Stock, attached hereto as
Exhibit A (the "Certificate of Determination") and Exhibit B the amendment to
the Certificate of Determination, which shall have been executed, acknowledged,
filed, recorded and become effective in accordance with the California
Corporations Code prior to the acceptance by the Company of this Agreement. The
solicitation of this Agreement and, if accepted by the Company, the offer and
sale of the Preferred Stock, and of the Common Stock issuable upon conversion or
exercise of the Preferred Stock, are being made in reliance upon the provisions
of Regulation D ("Regulation D") promulgated by the Securities and Exchange
Commission ("SEC") under the Securities Act of 1933, as amended (the "Securities
Act"), or under the exemption from registration set forth in Section 4(2) of the
Securities Act. The Preferred Stock and the Common Stock issuable upon
conversion or exercise thereof are sometimes collectively referred to in this
Agreement as the "Securities." The shares of Common Stock issuable upon
conversion of the Preferred Stock is sometimes referred to as the "Underlying
Stock." This Agreement is one of a series of subscription agreements, dated as
of the date hereof, entered into between the Company and the subscriber thereof.
The subscribers, together with the Subscriber, are sometimes collectively
referred to as the "Subscribers" and individually as "Subscriber."

         The Subscriber wishes to subscribe for, and the Company wishes to
issue, the number of shares of Preferred Stock at the aggregate purchase price
set forth in Section 13 and in accordance with the other terms and conditions of
this Agreement. In consideration of the mutual promises, representations,
warranties and conditions set forth herein, and intending to be legally bound
hereby, the Company and the Subscriber agree as follows:

1.       Purchase and Sale of Securities; Closing Conditions.

         1.1. Purchase and Sale of Securities.

                  (a) Initial Issuance. The Company shall issue and sell to the
Subscriber and the Subscriber shall purchase from the Company such number of
shares of Preferred Stock as is set forth in Section 13 hereof for an aggregate
purchase price as specified in such Section (the "Purchase Price").
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                                      -2-

                  (b) Form of Payment. On the Closing Date (as defined below),
(i) the Subscriber shall pay the portion of the Purchase Price for the Preferred
Stock to be issued and sold to the Subscriber at the applicable Closing by wire
transfer to the Company, in accordance with the Company's written wiring
instructions, against delivery of the duly executed share certificates
representing the Preferred Stock which the Subscriber is then purchasing, and
(ii) the Company shall deliver to the Subscriber such Preferred Stock
certificates against delivery of such Purchase Price.

                  (c) Closing Date. The date and time of the issuance and sale
of the Preferred Stock pursuant to this Agreement shall be, 12:00 noon Pacific
Daylight Time, on __________, 1998. The Closing shall occur at such places and
times, as the parties shall determine.

         1.2. Lock-up. Notwithstanding anything to the contrary set forth
herein, Subscriber agrees that it will not, without the prior written consent of
the Company, directly or indirectly, offer, sell, offer to sell, contract to
sell, pledge, grant any option to purchase or otherwise sell or dispose or
transfer (or announce any offer, sale, offer of sale, contract of sale or grant
of any option to purchase or other sale or disposition or transfer) of any of
the Underlying Stock for a period of 180 days subsequent to the date of this
Agreement. The Company agrees that if requested by Subscriber, the Company will
enter into a registration rights agreement pursuant to which Subscriber shall be
granted two "demand" and two "piggy-back" registrations following the expiration
of such lock-up period. The terms and conditions of such registration rights
agreement shall be consistent with the Company's existing obligations regarding
same.

         1.3. Series B Conversion Price: Notwithstanding anything to the
contrary in the Certificate of Designation, as amended, or the Company's
Articles of Incorporation, as amended, the Subscribers agree and acknowledge
that the Series B Conversion Price, as set forth in Section 4(d) of the
Certificate of Designation, as amended, shall be $0.50 per share, and that such
Conversion Price shall apply to all shares of Series B Preferred Stock,
including those shares previously acquired by the Subscribers.

         1.4. Automatic Conversion of Series B Preferred Stock: Notwithstanding
anything to the contrary in the Certificate of Designation, as amended, or the
Company's Articles of Incorporation, as amended, the Subscribers acknowledge
that the Company is currently in negotiations with MC Informatics ("MCI")
regarding a potential acquisition of the business of MCI (the "Acquisition"). It
is a condition to the proposed transaction with MCI that the Company's Series B
Preferred Stock converts upon the closing of such transaction. Accordingly, the
Subscribers agree and acknowledge that the Series B Preferred Stock purchased
herein or previously acquired by the Subscribers, shall automatically convert
into shares of the Company's Common Stock upon the closing of the Acquisition.
Each of the Subscribers agrees to return their certificate representing Series B
Preferred Stock for

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                                      -3-

exchange and to execute any other documents  reasonably requested by the Company
in order to effectuate the provisions of this paragraph.

2.       Representations and Warranties of Subscriber.

         The Subscriber represents and warrants to the Company that:

         2.1. No Government Recommendation or Approval. The Subscriber
understands that no United States federal or state agency or similar agency of
any other country has passed upon or made any recommendation or endorsement of
the Company or the offering of the Securities.

         2.2. Intent. The Subscriber is purchasing the Securities for its own
account and not with a view towards distribution thereof and the Subscriber has
no present arrangement (whether or not legally binding) at any time to sell the
Securities to or through any person or entity; provided, however, that by making
the representations herein, the Subscriber does not agree to hold the Securities
for any minimum or other specific term and reserves the right to dispose of the
Securities at any time in accordance with federal and state securities laws
applicable to such disposition. The Subscriber understands that the Securities
must be held indefinitely unless such Securities are subsequently registered
under the Securities Act or an exemption from registration is available. The
Subscriber has been advised or is aware of the provisions of Rule 144 under the
Securities Act.

         2.3. Sophisticated Investor. The Subscriber is an accredited investor
(as defined in Rule 501 of Regulation D) and the Subscriber has such experience
in business and financial matters that it is capable of evaluating the merits
and risks of an investment in the Securities. The Subscriber acknowledges that
the Securities are speculative and involve a high degree of risk. The Subscriber
acknowledges that there exists no public market for the Preferred Stock.

         2.4. Independent Investigation. The Subscriber, in making its decision
to purchase the Securities subscribed for hereunder, has relied upon an
independent investigation made by it and/or its representatives and has not
relied on any information or representations made by third parties or on any
oral or written representations or assurances from the Company or any
representative or agent of the Company, other than as set forth in this
Agreement, in the public filings of the Company and in the documents described
below. Prior to the date hereof, the Subscriber has been furnished with and has
reviewed the Company's latest proxy statement and Annual Report on Form 10-K
sent to the Company's shareholders and all documents filed by the Company with
the SEC pursuant to sections 13(a), 13(c), 14 or 15(d) of the Securities
Exchange Act of 1934, as amended (the "Exchange Act") (excluding preliminary
proxy statement filings) (such documents are collectively referred to in this
Agreement as the "Exchange Act Reports"). The Subscriber has had a reasonable
opportunity to ask questions of and receive answers from the Company concerning
the Company and the offering. The Subscriber acknowledges that the price and
terms of the


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                                      -4-

Securities  offered hereby has been determined by negotiation based, in part, on
the  market  price  for the  Common  Stock,  and does not  necessarily  bear any
relationship to the assets,  book value or potential  performance of the Company
or any other recognized criteria of value.

         2.5. Authority. This Agreement has been duly authorized and validly
executed and delivered by the Subscriber and is a valid and binding agreement of
the Subscriber enforceable against the Subscriber in accordance with its terms,
subject to general principles of equity and to bankruptcy or other laws
affecting the enforcement of creditors' rights generally.

         2.6. No Legal Advice From Company. The Subscriber acknowledges that it
has had the opportunity to review this Agreement and the transactions
contemplated by this Agreement with his or its own legal counsel and tax
advisors. Except for any statements or representations of the Company made in
this Agreement and in the Exchange Act Reports, the Subscriber is relying solely
on its counsel and advisors and not on any statements or representations of the
Company or any of its representative or agents for legal, tax or investment
advice with respect to this investment, the transactions contemplated by this
Agreement or the securities laws of any jurisdiction.

         2.7. No Brokers. The Subscriber has taken no action which would give
rise to any claim by any person for brokerage commissions, finder's fees or
similar payments by the Company relating to this Agreement, the Certificate of
Determination, or the transactions contemplated hereby and thereby.

         2.8. Reliance on Representations and Warranties. The Subscriber
understands that the Securities are being offered and sold to it in reliance on
specific provisions of United States federal and state securities laws and that
the Company is relying upon the truth and accuracy of the representations,
warranties, agreements, acknowledgments and understandings of the Subscriber set
forth in this Agreement in order to determine the applicability of such
provisions.

         2.9.  Residency.  The  Subscriber  is a  resident  of the  jurisdiction
identified on the signature page of this Agreement.

         2.10. Compliance With Laws. No governmental notifications, orders,
permissions, consents, approvals or authorizations are required to be made or
obtained by Subscriber and no registrations or declarations are required to be
filed by Subscriber in connection with the execution and delivery of this
Agreement or the acquisition of the Securities.

3.       Representations and Warranties of the Company.

         The Company represents and warrants to the Subscriber that:


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                                      -5-

         3.1. Company Status. The Company has registered its Common Stock
pursuant to Section 12(b) or 12(g) of the Exchange Act, is in full compliance
with all reporting requirements of the Exchange Act, and the Company has
maintained all requirements for the continued listing of its Common Stock, and
such Common Stock is currently listed on the Exchange.

         3.2. No Directed Selling Efforts or General Solicitation in Regard to
this Transaction. Neither the Company nor any of its affiliates nor any
distributor or any person acting on its or their behalf has conducted any
"directed selling efforts" with respect to the Preferred Stock nor has the
Company conducted any general solicitation (as that term is used in Regulation
D) with respect to any of the Securities, nor has any such person made any
offers or sales of any security or solicited any offers to buy any security,
under circumstances that would require registration of the Securities under the
Act.

         3.3. Capitalization; Valid Issuance of Securities and Capital Stock.
The Company has an authorized capitalization as disclosed in the Exchange Act
Reports. Other than the Securities and except for options granted pursuant to
the Company's stock option plan and warrants issued by the Company in connection
with the Company's initial public offering, there are no other outstanding
options, warrants, scrip, rights to subscribe to, or securities or rights
convertible into or exchangeable for, any shares of capital stock of the Company
or arrangements by which the Company is or may become bound to issue additional
shares of its capital stock. All of the issued and outstanding shares of capital
stock of the Company have been duly and validly authorized and issued and are
fully paid and non-assessable; assuming the filing of a Certificate of Amendment
to the Certificate of Determination increasing the authorized number of shares
of Series B Preferred Stock from 250 shares to 750 shares, upon issuance of the
Securities, the Securities will be duly and validly issued, fully paid and
non-assessable; the shares of Common Stock issuable upon conversion of the
Preferred Stock, when issued and delivered in accordance with the terms of the
Certificate of Determination, as amended, will be duly and validly issued, fully
paid and non-assessable; and the holders of outstanding capital stock of the
Company are not and shall not be entitled to preemptive or other rights afforded
by the Company to subscribe for the capital stock or other securities of the
Company as a result of the sale of the Securities or the issuance of Common
Stock upon the conversion or exercise thereof. The issuance of the Preferred
Stock will not cause any anti-dilution or similar adjustment to the conversion
or exchange rate of outstanding options or convertible securities exercisable
for or convertible into Common Stock. As of the Closing Date, the Company shall
have filed the Certificate of Determination, as amended, and all of the rights,
preferences and privileges of the Preferred Stock shall be as set forth in the
Certificate of Determination, as amended, and this Agreement.

         3.4. Intentionally Omitted.

         3.5. Organization and Qualification. The Company and each of its
subsidiaries, if any, is a corporation duly incorporated and validly existing in
good standing under the laws

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                                      -6-

of the jurisdiction of its incorporation and has the requisite corporate power
to own its properties and to carry on its business as now being conducted. The
Company does not have any active subsidiaries, except for those listed in the
Exchange Act Reports. The Company and each such subsidiary, if any, is duly
qualified as a foreign corporation to do business and is in good standing in
every jurisdiction in which the nature of the business conducted or property
owned by it makes such qualification necessary other than those in which the
failure so to qualify would not have a Material Adverse Effect. "Material
Adverse Effect" means any effect on the business, operations, properties or
prospects, or financial condition of the entity and its subsidiaries, with
respect to which such term is used and which is material and adverse to such
entity, its subsidiaries and any other entity controlling or controlled by such
entity, on a consolidated basis, and/or any condition or situation which would
prohibit or otherwise interfere with the ability of the entity and its
subsidiaries, on a consolidated basis, with respect to which said term is used
to enter into and perform its obligations under this Agreement.

         3.6. Authorization; Enforcement. (i) The Company has the requisite
corporate power and authority to enter into and perform this Agreement and to
issue the Securities in accordance with the terms hereof and thereof; (ii) the
execution, delivery and performance of this Agreement, and the Certificate of
Determination, as amended, by the Company and the consummation by it of the
transactions contemplated hereby and thereby; (iii) this Agreement and the
Certificate of Determination, as amended, have been duly executed and delivered
by the Company, and (iv) this Agreement and the Certificate of Determination, as
amended, constitute, and upon issuance and delivery thereof the Preferred Stock
shall be, valid and binding obligations of the Company enforceable against the
Company in accordance with their terms, except as such enforceability may be
limited by applicable bankruptcy, insolvency, or similar laws relating to, or
affecting generally the enforcement of, creditors' rights and remedies or by
other equitable principles of general application.

         3.7. Corporate Documents. The Company has furnished or made available
to the Subscriber true and correct copies of the Company's Articles of
Incorporation as amended and in effect on the date hereof (the "Articles"), and
the Company's Bylaws as amended and in effect on the date hereof (the "Bylaws").

         3.8. No Conflicts. The execution, delivery and performance by the
Company of this Agreement, the Certificate of Determination, as amended, and the
consummation by the Company of the transactions contemplated hereby and thereby,
including without limitation the issuance of Common Stock upon the conversion or
exercise thereof, do not and will not (i) result in a violation of the Articles
or Bylaws or (ii) conflict with or constitute a default (or an event which with
notice or lapse of time or both would become a default) under, or give to others
any rights of termination, amendment, acceleration or cancellation of, any
agreement, indenture or instrument to which the Company or any of its
subsidiaries is a party, or result in a violation of any federal, state, local
or foreign law, rule, regulation, order, judgment or decree (including federal
and state securities laws and regulations) applicable to the Company or any of
its subsidiaries or by which any property or asset of the


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                                      -7-

Company or any of its subsidiaries is bound or affected (except for such
conflicts, defaults, terminations, amendments, accelerations, cancellations and
violations as would not, individually or in the aggregate, have a Material
Adverse Effect); provided, that, for purposes of such representation as to
federal, state, local or foreign law, rule or regulation, no representation is
made herein with respect to any of the same applicable solely to the Subscriber
and not to the Company. The business of the Company is not being conducted in
violation of any law, ordinance or regulation of any governmental entity, in any
manner that is inconsistent with or in violation of the Articles or Bylaws, or
in violation of any contract or agreement to which the Company is a party,
except for possible violations which either singly or in the aggregate do not
and will not have a Material Adverse Effect. The Company is not required under
federal, state or local law, rule or regulation in the United States to obtain
any consent, authorization or order of, or make any filing or registration with,
any court or governmental agency in order for it to execute, deliver or perform
any of its obligations under this Agreement, the Certificate of Determination,
as amended, or any of the Securities or to issue and sell the Securities in
accordance with the terms hereof and thereof (other than any SEC, NASD, Exchange
(as defined below) or state securities filings which may be required to be made
by the Company from time to time, and any registration statement which may be
filed pursuant hereto); provided, that, for purposes of the representation made
in this sentence, the Company is assuming and relying upon the accuracy of the
relevant representations and agreements of the Subscriber herein.

         3.9. Exchange Act Reports. The Company has delivered or made available
to the Subscriber true and complete copies of the Exchange Act Reports
(including, without limitation, proxy information and solicitation materials).
As of their respective dates, the Exchange Act Reports complied in all material
respects with the requirements of the Exchange Act and rules and regulations of
the SEC promulgated thereunder and other federal, state and local laws, rules
and regulations applicable to such Exchange Act Reports, and none of the
Exchange Act Reports contained any untrue statement of a material fact or
omitted to state a material fact required to be stated therein or necessary in
order to make the statements therein, in light of the circumstances under which
they were made, not misleading. The financial statements of the Company included
in the Exchange Act Reports comply as to form in all material respects with
applicable accounting requirements and the published rules and regulations of
the SEC or other applicable rules and regulations with respect thereto. Such
financial statements have been prepared in accordance with generally accepted
accounting principles applied on a consistent basis during the periods involved
(except (i) as may be otherwise indicated in such financial statements or the
notes thereto or (ii) in the case of unaudited interim statements, to the extent
they may not include footnotes or may be condensed or summary statements) and
fairly present in all material respects the financial position of the Company as
of the dates thereof and the results of operations and cash flows for the
periods then ended (subject, in the case of unaudited statements, to normal
year-end audit adjustments). As of the Closing Date, the Company has filed all
reports required to be filed by it pursuant to the Exchange Act.


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                                      -8-

         3.10. No Material Adverse Change. Since March 31, 1998, no event or
circumstance has occurred or arisen which has had or is reasonably likely to
have a Material Adverse Effect on the Company or its subsidiaries, except as
noted in the press releases which relate to the restructuring of the Company and
the resignation of certain officers. Since March 31, 1998, neither the Company
nor any of its subsidiaries has (i) incurred or become subject to any material
liabilities (absolute or contingent) except liabilities incurred in the ordinary
course of business consistent with past practices; (ii) discharged or satisfied
any material lien or encumbrance or paid any material obligation or liability
(absolute or contingent), other than current liabilities paid in the ordinary
course of business consistent with past practices; (iii) declared or made any
payment or distribution of cash or other property to stockholders with respect
to its capital stock, or purchased or redeemed, or made agreements to purchase
or redeem, any shares of its capital stock; (iv) sold, assigned or transferred
any other tangible assets with a value greater than in the aggregate, or
canceled any debts or claims, except in the ordinary course of business
consistent with past practices; (v) suffered any substantial losses or waived
any rights of material value, whether or not in the ordinary course of business,
or suffered the loss of any material amount of existing business; (vi) made any
changes in employee compensation except in the ordinary course of business
consistent with past practices; or (vii) experienced any material problems with
labor or management in connection with the terms and conditions of their
employment.

         3.11. No Undisclosed Liabilities. The Company and its subsidiaries have
no liabilities or obligations which are material, individually or in the
aggregate, and are not disclosed in the Exchange Act Reports, other than those
incurred in the ordinary course of the Company's or its subsidiaries' respective
businesses since March 31, 1998 and which, individually or in the aggregate, do
not or would not have a Material Adverse Effect on the Company or any of its
subsidiaries, except such liabilities, which may arise as the result of the
restructuring of the Company and the resignation of certain officers.

         3.12. No Undisclosed Events or Circumstances. No event or circumstance
has occurred or exists with respect to the Company or its subsidiaries or their
respective businesses, properties, prospects, operations or financial condition,
which, under applicable law, rule or regulation, requires public disclosure or
announcement prior to the date hereof by the Company but which has not been so
publicly announced or disclosed.

         3.13. No Integrated Offering. Neither the Company, nor any of its
affiliates, nor any person acting on its or their behalf has, directly or
indirectly, at any time since March 31, 1998, made any offers or sales of any
security or solicited any offers to buy any security under circumstances that
would eliminate the availability of the exemption from registration under
Regulation D promulgated under the Securities Act in connection with the offer
and sale of the Securities as contemplated hereby.

         3.14. No Brokers. The Company has taken no action which would give rise
to any claim by any person for brokerage commissions, finder's fees or similar
payments by the


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                                      -9-

Subscriber relating to this Agreement,  or the Certificate of Determination,  as
amended, for the transactions contemplated hereby and thereby.

         3.15. Absence of Litigation. Except as disclosed in the Exchange Act
Reports, there is no action, suit, proceeding, inquiry or organization or body
pending or, to the knowledge of the Company or any of its subsidiaries,
threatened against or affecting the Company or any of its subsidiaries, wherein
an unfavorable decision, ruling or finding would have a Material Adverse Effect.

         3.16. Intellectual Property Rights. There is no claim, action or
proceeding being made or brought against, or to the Company's knowledge, being
threatened against, the Company or any of its subsidiaries, with respect to the
infringement by the Company or any of its subsidiaries of any trademarks, trade
name rights, patents, patent rights, copyrights, inventions, licenses, service
names, service marks, service mark registrations, trade secret or other similar
rights of others, or of any such development of similar or identical trade
secrets or technical information by others. The Company and its subsidiaries
have taken reasonable security measures to protect the secrecy, confidentiality
and value of all of their intellectual properties.

         3.17. Title to Properties and Assets, Liens, etc. The Company has good
and marketable title to its tangible properties and assets, subject to no
mortgage, pledge, lien, encumbrance or charge, other than liens resulting from
taxes which have not yet become delinquent and liens and encumbrances which do
not in any case materially detract from the value of the property subject
thereto or materially impair the operations of the Company.

         3.18. Tax Status. The Company and each of its subsidiaries has made or
filed all federal and state income and all other tax returns, reports and
declarations required by any jurisdiction to which it is subject (unless and
only to the extent that the Company and each of its subsidiaries has set aside
on its books provisions reasonably adequate for the payment of all unpaid and
unreported taxes) and has paid all taxes and other governmental assessments and
charges that are material in amount, shown or determined to be due on such
returns, reports and declarations, except those being contested in good faith,
and has set aside on its books provisions reasonably adequate for the payment of
all taxes for periods subsequently to the periods to which such returns, reports
or declarations apply. There are no unpaid taxes in any material amount claimed
to be due by the taxing authority of any jurisdiction, and the officers of the
Company know of no basis for any such claim.

4.       Covenants of the Company.

         4.1. Reservation of Common Stock. As of the date hereof, the Company
has reserved and the Company shall continue to reserve and keep available at all
times, free of preemptive rights, a sufficient number of shares of Common Stock
for the purpose of enabling the Company to satisfy any obligation to issue
shares of its Common Stock upon conversion of the Preferred Stock. The number of
shares so reserved may be reduced by the


<PAGE>
                                      -10-

number of shares  actually  delivered  pursuant to conversion of Preferred Stock
and the number of shares so reserved shall be increased to reflect stock splits,
stock dividends and other distributions.

         4.4. Listing of Underlying Shares. The Company hereby agrees, promptly
following the Closing, to use its reasonable best efforts to cause the
Underlying Stock to be listed on the Nasdaq SmallCap Market (the "Exchange").
The Company further agrees, if the Company applies to have the Common Stock
traded on any other principal stock exchange or market, it will include in such
application the Underlying Stock will take such other action as is necessary or
desirable to cause the Underlying Stock to be listed on such other exchange or
market.

         4.5. Exchange Act Registration. The Company will cause its Common Stock
to continue to be registered under Section 12(g) or 12(b) of the Exchange Act,
will comply in all respects with its reporting and filing obligations under the
Exchange Act, and will not take any action or file any document (whether or not
permitted by said Act or the rules thereunder) to terminate or suspend such
registration or to terminate or suspend its reporting and filing obligations
under said Act. The Company will take all action under its control to continue
the listing and trading of its Common Stock on the Exchange and will comply in
all respects with the Company's reporting, filing and other obligations under
the bylaws or rules of the NASD and the Exchange.

         4.6. Corporate Existence.  The Company will take all steps necessary to
preserve and continue its corporate existence.

5.       Legends.

         5.1. Legends. The Company will issue one or more certificates
representing the Preferred Stock, in the name of the Subscriber. The Preferred
Stock (including the additional shares of Preferred Stock) and certificates
evidencing any shares of Common Stock issued upon conversion or exercise thereof
will bear the following legend (the "Legend"):

         THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
         1933 OR ANY STATE SECURITIES LAWS. THEY MAY NOT BE SOLD OR OFFERED FOR
         SALE EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SAID
         ACT AND ANY APPLICABLE STATE SECURITIES LAWS OR AN APPLICABLE EXEMPTION
         FROM SUCH REGISTRATION REQUIREMENTS.

         THESE SECURITIES ARE SUBJECT TO A LOCK-UP AGREEMENT BY AND AMONG THE
         HOLDERS OF THE SECURITIES, HEALTHDESK CORPORATION (THE "CORPORATION")
         PURSUANT TO WHICH THE HOLDER OF SUCH SECURITY MAY NOT, WITHOUT THE
         PRIOR


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                                      -11-

         WRITTEN CONSENT OF THE UNDERWRITER, DIRECTLY OR INDIRECTLY, SELL,
         OFFER FOR SALE, TRANSFER OR OTHERWISE DISPOSE OF SUCH SECURITIES FOR A
         PERIOD OF 180 DAYS FOLLOWING _________, 1998.

         If applicable, the Company shall reissue certificates representing the
Preferred Stock, or the Underlying Stock, as the case may be, without the Legend
set forth above at such time as the Holder thereof is permitted to dispose
thereof pursuant to Rule 144(k) under the Act.

         5.2. No Other Legend or Stock Transfer Restrictions. No Legend has been
or shall be placed on the share certificates representing the Securities and no
instructions or "stop transfers," "stock transfer restrictions," or other
restrictions have been or shall be given to the Company's transfer agent with
respect thereto other than as set forth in this Section 5.

         5.3. Subscriber's Compliance. Nothing in this section shall affect in
any way the Subscriber's obligations under and agreement to comply with all
applicable securities laws upon resale of the Securities.

6.       Choice of Law and Venue.

         This Agreement shall be construed under the laws of the State of
California, without regard to principles of conflicts of law or choice of law
thereof. The parties hereby (i) irrevocably submits to the exclusive
jurisdiction of the United States District Court for the Northern District of
California for the purposes of any suit, action or proceeding arising out of or
relating to this Agreement, or the Certificate of Determination, as amended, and
(ii) waives, and agrees not to assert in any such suit, action or proceeding,
any claim that it is not personally subject to the jurisdiction of such court,
that the suit, action or proceeding is brought in an inconvenient forum or that
the venue of the suit, action or proceeding is improper. Each of the parties
consents to process being served in any such suit, action or proceeding by
sending a copy thereof to such party by following the provision for notices to
it under this Agreement and agrees that such service shall constitute good and
sufficient service of process and notice thereof. Nothing in this paragraph
shall affect or limit any right to serve process in any other manner permitted
by law.

7.       Assignment; Entire Agreement; Amendment.

         7.1. Assignment. Neither this Agreement nor any rights of the
Subscriber hereunder may be assigned by either party to any other person, except
that the Subscriber may transfer rights under this Agreement to its affiliates.
Notwithstanding the foregoing, the provisions of this Agreement shall inure to
the benefit of, and be enforceable by, any transferee of any of the Securities
purchased or acquired by the Subscriber hereunder with respect to the Securities
held by such person.


<PAGE>
                                      -12-

         7.2. Entire Agreement; Amendment. This Agreement, the Certificate of
Determination, and the other documents delivered pursuant hereto constitute the
full and entire understanding and agreement between the parties with regard to
the subject matter hereof and thereof, and no party shall be liable or bound to
any other party in any manner by any warranties, representations or covenants
except as specifically set forth in this Agreement or therein. Except as
expressly provided in this Agreement, neither this Agreement nor any term hereof
may be amended, waived, discharged or terminated other than by a written
instrument signed by the party against whom enforcement of any such amendment,
waiver, discharge or termination is sought.

8.       Publicity.

         The Company agrees that it will not disclose, and will not include in
any public announcement regarding this Agreement, the name of the Subscriber
without its consent, unless and until such disclosure is required by law or
applicable regulation, and then only to the extent of such requirement and with
the prior approval of the Subscriber which the Subscriber agrees will not be
unreasonably withheld or delayed.

9.       Notices, etc.; Expenses; Indemnity.

         9.1. Notices. Any notice, demand or request required or permitted to be
given by either the Company or the Subscriber pursuant to the terms of this
Agreement shall be in writing and shall be deemed given when delivered
personally or by facsimile, with a hard copy to follow by two day courier
addressed to the parties at the addresses of the parties set forth at the end of
this Agreement or such other address as a party may request by notifying the
other in writing. Copies of all notices to the Subscriber shall be sent to its
designee or representative.

         9.2. Cost and Expenses. The Company and the Subscribers shall each be
responsible for their own costs and expenses (including legal fees) incurred in
entering into this Agreement. In connection with any suit or other proceeding
arising out of any breach by any party to this Agreement of any of the
representations, covenants or agreements of such party hereunder, or in
connection with the exercise by any party of any of its rights or remedies
hereunder or under applicable law upon any breach by the other party of any of
its representations, covenants or agreements under this Agreement, or with
respect to the Company, the Certificate of Determination, the prevailing party
in such suit or proceeding shall be entitled to receive from the non-prevailing
party all of such prevailing party's reasonable costs and expenses (including
legal fees) incurred in connection therewith.


<PAGE>
                                      -13-

10.      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.

11.      Survival; Severability.

         The representations, warranties, covenants and agreements of the
parties hereto shall survive the Closing; provided that the representations and
warranties shall survive only until the third anniversary of the Closing. In the
event that any provision of this Agreement becomes or is declared by a court of
competent jurisdiction to be illegal, unenforceable or void, this Agreement
shall continue in full force and effect without said provision.

12.      Title 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.


         [The remainder of this page has been intentionally left blank.]


<PAGE>
                                      -14-

13.      Amount.

         The undersigned Subscriber hereby subscribes for [_______] shares of
Preferred Stock and agrees to pay therefor funds in the amount of _______
Million Dollars (U.S. $___________).

         The undersigned acknowledges that this subscription shall not be
effective unless accepted by the Company as indicated below.

                                 Name of Subscriber:

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


                                 By_____________________________
                                      Name:
                                      Title:

                                 Date of Subscription:
                                                      ----------------------
                                 Place of Execution:
                                                    ------------------------ 
                                 Place of Organization or Citizenship:
                                 ------------------------------

                                 Place of Residency and/or Principal Place of
                                 Business: ---------------------

                                 Address: --------------------------
                                          --------------------------


         THIS SUBSCRIPTION IS ACCEPTED BY THE COMPANY ON THE _____ DAY
OF ______ 1998.

                                     HEALTHDESK CORPORATION



                                     By: ___________________________________
                                     Name: _________________________________
                                     Title: ________________________________