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                                                                   Exhibit 10.16
                               INDEMNITY AGREEMENT

      THIS AGREEMENT is made and entered into this _____ day of
________________, 2000 by and between PHARSIGHT CORPORATION, a Delaware
corporation (the "Corporation"), and __________ ("Agent").

                                    RECITALS

      WHEREAS, Agent performs a valuable service to the Corporation in his
capacity as _______ of the Corporation;

      WHEREAS, the stockholders of the Corporation have adopted bylaws (the
"Bylaws") providing for the indemnification of the directors, officers,
employees and other agents of the Corporation, including persons serving at the
request of the Corporation in such capacities with other corporations or
enterprises, as authorized by the Delaware General Corporation Law, as amended
(the "Code");

      WHEREAS, the Bylaws and the Code, by their non-exclusive nature, permit
contracts between the Corporation and its agents, officers, employees and other
agents with respect to indemnification of such persons; and

      WHEREAS, in order to induce Agent to continue to serve as _________ of the
Corporation, the Corporation has determined and agreed to enter into this
Agreement with Agent;

      NOW, THEREFORE, in consideration of Agent's continued service as ________
after the date hereof, the parties hereto agree as follows:

                                    AGREEMENT

      1. Services to the Corporation. Agent will serve, at the will of the
Corporation or under separate contract, if any such contract exists, as
__________ of the Corporation or as a director, officer or other fiduciary of an
affiliate of the Corporation (including any employee benefit plan of the
Corporation) faithfully and to the best of his ability so long as he is duly
elected and qualified in accordance with the provisions of the Bylaws or other
applicable charter documents of the Corporation or such affiliate; provided,
however, that Agent may at any time and for any reason resign from such position
(subject to any contractual obligation that Agent may have assumed apart from
this Agreement) and that the Corporation or any affiliate shall have no
obligation under this Agreement to continue Agent in any such position.

      2. Indemnity of Agent. The Corporation hereby agrees to hold harmless and
indemnify Agent to the fullest extent authorized or permitted by the provisions
of the Bylaws and the Code, as the same may be amended from time to time (but,
only to the extent that such amendment permits the Corporation to provide
broader indemnification rights than the Bylaws or the Code permitted prior to
adoption of such amendment).


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      3. Additional Indemnity. In addition to and not in limitation of the
indemnification otherwise provided for herein, and subject only to the
exclusions set forth in Section 4 hereof, the Corporation hereby further agrees
to hold harmless and indemnify Agent:

            (a) against any and all expenses (including attorneys' fees),
witness fees, damages, judgments, fines and amounts paid in settlement and any
other amounts that Agent becomes legally obligated to pay because of any claim
or claims made against or by him in connection with any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, arbitrational,
administrative or investigative (including an action by or in the right of the
Corporation) to which Agent is, was or at any time becomes a party, or is
threatened to be made a party, by reason of the fact that Agent is, was or at
any time becomes a director, officer, employee or other agent of Corporation, or
is or was serving or at any time serves at the request of the Corporation as a
director, officer, employee or other agent of another corporation, partnership,
joint venture, trust, employee benefit plan or other enterprise; and

            (b) otherwise to the fullest extent as may be provided to Agent by
the Corporation under the non-exclusivity provisions of the Code and the Bylaws.

      4. Limitations on Additional Indemnity. No indemnity pursuant to Section 3
hereof shall be paid by the Corporation:

            (a) on account of any claim against Agent solely for an accounting
of profits made from the purchase or sale by Agent of securities of the
Corporation pursuant to the provisions of Section 16(b) of the Securities
Exchange Act of 1934 and amendments thereto or similar provisions of any
federal, state or local statutory law;

            (b) on account of Agent's conduct that is established by a final
judgment as knowingly fraudulent or deliberately dishonest or that constituted
willful misconduct;

            (c) on account of Agent's conduct that is established by a final
judgment as constituting a breach of Agent's duty of loyalty to the Corporation
or resulting in any personal profit or advantage to which Agent was not legally
entitled;

            (d) for which payment is actually made to Agent under a valid and
collectible insurance policy or under a valid and enforceable indemnity clause,
bylaw or agreement, except in respect of any excess beyond payment under such
insurance, clause, bylaw or agreement;

            (e) if indemnification is not lawful (and, in this respect, both the
Corporation and Agent have been advised that the Securities and Exchange
Commission believes that indemnification for liabilities arising under the
federal securities laws is against public policy and is, therefore,
unenforceable and that claims for indemnification should be submitted to
appropriate courts for adjudication); or

            (f) in connection with any proceeding (or part thereof) initiated by
Agent, or any proceeding by Agent against the Corporation or its directors,
officers, employees or other agents, unless (i) such indemnification is
expressly required to be made by law, (ii) the


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proceeding was authorized by the Board of Directors of the Corporation, (iii)
such indemnification is provided by the Corporation, in its sole discretion,
pursuant to the powers vested in the Corporation under the Code, or (iv) the
proceeding is initiated pursuant to Section 9 hereof.

      5. Continuation of Indemnity. All agreements and obligations of the
Corporation contained herein shall continue during the period Agent is a
director, officer, employee or other agent of the Corporation (or is or was
serving at the request of the Corporation as a director, officer, employee or
other agent of another corporation, partnership, joint venture, trust, employee
benefit plan or other enterprise) and shall continue thereafter so long as Agent
shall be subject to any possible claim or threatened, pending or completed
action, suit or proceeding, whether civil, criminal, arbitrational,
administrative or investigative, by reason of the fact that Agent was serving in
the capacity referred to herein.

      6. Partial Indemnification. Agent shall be entitled under this Agreement
to indemnification by the Corporation for a portion of the expenses (including
attorneys' fees), witness fees, damages, judgments, fines and amounts paid in
settlement and any other amounts that Agent becomes legally obligated to pay in
connection with any action, suit or proceeding referred to in Section 3 hereof
even if not entitled hereunder to indemnification for the total amount thereof,
and the Corporation shall indemnify Agent for the portion thereof to which Agent
is entitled.

      7. Notification and Defense of Claim. Not later than thirty (30) days
after receipt by Agent of notice of the commencement of any action, suit or
proceeding, Agent will, if a claim in respect thereof is to be made against the
Corporation under this Agreement, notify the Corporation of the commencement
thereof; but the omission so to notify the Corporation will not relieve it from
any liability which it may have to Agent otherwise than under this Agreement.
With respect to any such action, suit or proceeding as to which Agent notifies
the Corporation of the commencement thereof:

            (a) the Corporation will be entitled to participate therein at its
own expense;

            (b) except as otherwise provided below, the Corporation may, at its
option and jointly with any other indemnifying party similarly notified and
electing to assume such defense, assume the defense thereof, with counsel
reasonably satisfactory to Agent. After notice from the Corporation to Agent of
its election to assume the defense thereof, the Corporation will not be liable
to Agent under this Agreement for any legal or other expenses subsequently
incurred by Agent in connection with the defense thereof except for reasonable
costs of investigation or otherwise as provided below. Agent shall have the
right to employ separate counsel in such action, suit or proceeding but the fees
and expenses of such counsel incurred after notice from the Corporation of its
assumption of the defense thereof shall be at the expense of Agent unless (i)
the employment of counsel by Agent has been authorized by the Corporation, (ii)
Agent shall have reasonably concluded, and so notified the Corporation, that
there is an actual conflict of interest between the Corporation and Agent in the
conduct of the defense of such action or (iii) the Corporation shall not in fact
have employed counsel to assume the defense of such action, in each of which
cases the fees and expenses of Agent's separate counsel shall be at the


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expense of the Corporation. The Corporation shall not be entitled to assume the
defense of any action, suit or proceeding brought by or on behalf of the
Corporation or as to which Agent shall have made the conclusion provided for in
clause (ii) above; and

            (c) the Corporation shall not be liable to indemnify Agent under
this Agreement for any amounts paid in settlement of any action or claim
effected without its written consent, which shall not be unreasonably withheld.
The Corporation shall be permitted to settle any action except that it shall not
settle any action or claim in any manner which would impose any penalty or
limitation on Agent without Agent's written consent, which may be given or
withheld in Agent's sole discretion.

      8. Expenses. The Corporation shall advance, prior to the final disposition
of any proceeding, promptly following request therefor, all expenses incurred by
Agent in connection with such proceeding upon receipt of an undertaking by or on
behalf of Agent to repay said amounts if it shall be determined ultimately that
Agent is not entitled to be indemnified under the provisions of this Agreement,
the Bylaws, the Code or otherwise.

      9. Enforcement. Any right to indemnification or advances granted by this
Agreement to Agent shall be enforceable by or on behalf of Agent in any court of
competent jurisdiction if (i) the claim for indemnification or advances is
denied, in whole or in part, or (ii) no disposition of such claim is made within
ninety (90) days of request therefor. Agent, in such enforcement action, if
successful in whole or in part, shall be entitled to be paid also the expense of
prosecuting his claim. It shall be a defense to any action for which a claim for
indemnification is made under Section 3 hereof (other than an action brought to
enforce a claim for expenses pursuant to Section 8 hereof, provided that the
required undertaking has been tendered to the Corporation) that Agent is not
entitled to indemnification because of the limitations set forth in Section 4
hereof. Neither the failure of the Corporation (including its Board of Directors
or its stockholders) to have made a determination prior to the commencement of
such enforcement action that indemnification of Agent is proper in the
circumstances, nor an actual determination by the Corporation (including its
Board of Directors or its stockholders) that such indemnification is improper
shall be a defense to the action or create a presumption that Agent is not
entitled to indemnification under this Agreement or otherwise.

      10. Subrogation. In the event of payment under this Agreement, the
Corporation shall be subrogated to the extent of such payment to all of the
rights of recovery of Agent, who shall execute all documents required and shall
do all acts that may be necessary to secure such rights and to enable the
Corporation effectively to bring suit to enforce such rights.

      11. Non-Exclusivity of Rights. The rights conferred on Agent by this
Agreement shall not be exclusive of any other right which Agent may have or
hereafter acquire under any statute, provision of the Corporation's Certificate
of Incorporation or Bylaws, agreement, vote of stockholders or directors, or
otherwise, both as to action in his official capacity and as to action in
another capacity while holding office.


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      12. Survival of Rights.

            (a) The rights conferred on Agent by this Agreement shall continue
after Agent has ceased to be a director, officer, employee or other agent of the
Corporation or to serve at the request of the Corporation as a director,
officer, employee or other agent of another corporation, partnership, joint
venture, trust, employee benefit plan or other enterprise and shall inure to the
benefit of Agent's heirs, executors and administrators.

            (b) The Corporation shall require any successor (whether direct or
indirect, by purchase, merger, consolidation or otherwise) to all or
substantially all of the business or assets of the Corporation, expressly to
assume and agree to perform this Agreement in the same manner and to the same
extent that the Corporation would be required to perform if no such succession
had taken place.

      13. Separability. Each of the provisions of this Agreement is a separate
and distinct agreement and independent of the others, so that if any provision
hereof shall be held to be invalid for any reason, such invalidity or
unenforceability shall not affect the validity or enforceability of the other
provisions hereof. Furthermore, if this Agreement shall be invalidated in its
entirety on any ground, then the Corporation shall nevertheless indemnify Agent
to the fullest extent provided by the Bylaws, the Code or any other applicable
law.

      14. Governing Law. This Agreement shall be interpreted and enforced in
accordance with the laws of the State of Delaware.

      15. Amendment and Termination. No amendment, modification, termination or
cancellation of this Agreement shall be effective unless in writing signed by
both parties hereto.

      16. Identical Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall for all purposes be deemed to be an original
but all of which together shall constitute but one and the same Agreement. Only
one such counterpart need be produced to evidence the existence of this
Agreement.

      17. Headings. The headings of the sections of this Agreement are inserted
for convenience only and shall not be deemed to constitute part of this
Agreement or to affect the construction hereof.

      18. Notices. All notices, requests, demands and other communications
hereunder shall be in writing and shall be deemed to have been duly given (i)
upon delivery if delivered by hand to the party to whom such communication was
directed or (ii) upon the third business day after the date on which such
communication was mailed if mailed by certified or registered mail with postage
prepaid:

            (a) If to Agent, at the address indicated on the signature page
hereof.


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            (b) If to the Corporation, to:

                Pharsight Corporation
                800 West El Camino Real, Suite 200
                Mountain View, CA 94040

or to such other address as may have been furnished to Agent by the Corporation.

      IN WITNESS WHEREOF, the parties hereto have executed this Agreement on and
as of the day and year first above written.

                                    PHARSIGHT CORPORATION

                                    By:_________________________________________
                                       Arthur Reidel
                                       President and Chief Executive Officer


                                    AGENT

                                    By:_________________________________________

                                       Name:____________________________________

                                       Address:_________________________________

                                               _________________________________


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