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                            INDEMNIFICATION AGREEMENT

     This Indemnification Agreement (the "AGREEMENT") is made as of March ___,
2000, by and between Rosetta Inpharmatics, Inc., a Delaware corporation (the
"COMPANY"), and _________________ (the "Indemnitee").

                                    RECITALS

     The Company and Indemnitee recognize the increasing difficulty in obtaining
liability insurance for directors, officers and key employees, the significant
increases in the cost of such insurance and the general reductions in the
coverage of such insurance. The Company and Indemnitee further recognize the
substantial increase in corporate litigation in general, subjecting directors,
officers and key employees to expensive litigation risks at the same time as the
availability and coverage of liability insurance has been severely limited.
Indemnitee does not regard the current protection available as adequate under
the present circumstances, and Indemnitee and agents of the Company may not be
willing to continue to serve as agents of the Company without additional
protection. The Company desires to attract and retain the services of highly
qualified individuals, such as Indemnitee, and to indemnify its directors,
officers and key employees so as to provide them with the maximum protection
permitted by law.

                                    AGREEMENT

     In consideration of the mutual promises made in this Agreement, and for
other good and valuable consideration, receipt of which is hereby acknowledged,
the Company and Indemnitee hereby agree as follows:

     1.   INDEMNIFICATION

          (a) Third Party Proceedings. The Company shall indemnify Indemnitee if
Indemnitee is or was a party or is threatened to be made a party to any
threatened, pending or completed action, suit or proceeding, whether civil,
criminal, administrative or investigative (other than an action by or in the
right of the Company) by reason of the fact that Indemnitee is or was a
director, officer, employee or agent of the Company, or any subsidiary of the
Company, by reason of any action or inaction on the part of Indemnitee while an
officer or director or by reason of the fact that Indemnitee is or was serving
at the request of the Company as a director, officer, employee or agent of
another corporation, partnership, joint venture, trust or other enterprise,
against expenses (including attorneys' fees), judgments, fines and amounts paid
in settlement (if such settlement is approved in advance by the Company, which
approval shall not be unreasonably withheld) actually and reasonably incurred by
Indemnitee in connection with such action, suit or proceeding if Indemnitee
acted in good faith and in a manner Indemnitee reasonably believed to be in or
not opposed to the best interests of the Company, and, with respect to any
criminal action or proceeding, had no reasonable cause to believe Indemnitee's
conduct was unlawful. The termination of any action, suit or proceeding by
judgment, order,


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settlement, conviction, or upon a plea of nolo contendere or its equivalent,
shall not, of itself, create a presumption that Indemnitee did not act in good
faith and in a manner which Indemnitee reasonably believed to be in or not
opposed to the best interests of the Company, or, with respect to any criminal
action or proceeding, that Indemnitee had reasonable cause to believe that
Indemnitee's conduct was unlawful.

          (b) Proceedings By or in the Right of the Company. The Company shall
indemnify Indemnitee if Indemnitee was or is a party or is threatened to be made
a party to any threatened, pending or completed action or proceeding by or in
the right of the Company or any subsidiary of the Company to procure a judgment
in its favor by reason of the fact that Indemnitee is or was a director,
officer, employee or agent of the Company, or any subsidiary of the Company, by
reason of any action or inaction on the part of Indemnitee while an officer or
director or by reason of the fact that Indemnitee is or was serving at the
request of the Company as a director, officer, employee or agent of another
corporation, partnership, joint venture, trust or other enterprise, against
expenses (including attorneys' fees) and, to the fullest extent permitted by
law, amounts paid in settlement (if such settlement is approved in advance by
the Company, which approval shall not be unreasonably withheld), in each case to
the extent actually and reasonably incurred by Indemnitee in connection with the
defense or settlement of such action or suit if Indemnitee acted in good faith
and in a manner Indemnitee reasonably believed to be in or not opposed to the
best interests of the Company and its stockholders, except that no
indemnification shall be made in respect of any claim, issue or matter as to
which Indemnitee shall have been finally adjudicated by court order or judgment
to be liable to the Company in the performance of Indemnitee's duty to the
Company and its stockholders unless and only to the extent that the court in
which such action or proceeding is or was pending shall determine upon
application that, in view of all the circumstances of the case, Indemnitee is
fairly and reasonably entitled to indemnity for such expenses which such court
shall deem proper.

          (c) Mandatory Payment of Expenses. To the extent that Indemnitee has
been successful on the merits or otherwise in defense of any action, suit or
proceeding referred to in Section 1(a) or Section 1(b) or the defense of any
claim, issue or matter therein, Indemnitee shall be indemnified against expenses
(including attorneys' fees) actually and reasonably incurred by Indemnitee in
connection therewith.

     2.   NO EMPLOYMENT RIGHTS. Nothing contained in this Agreement is intended
to create in Indemnitee any right to continued employment.

     3.   EXPENSES; INDEMNIFICATION PROCEDURE

          (a) ADVANCEMENT OF EXPENSES. The Company shall advance all expenses
incurred by Indemnitee in connection with the investigation, defense, settlement
or appeal of any civil or criminal action, suit or proceeding referred to in
Section l(a) or Section 1(b) hereof (including amounts actually paid in
settlement of any such action, suit or proceeding). Indemnitee hereby undertakes
to repay such amounts advanced only if, and to the extent that, it shall


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ultimately be determined that Indemnitee is not entitled to be indemnified by
the Company as authorized hereby. Any advances to be made under this Agreement
shall be paid by the Company to Indemnitee within twenty (20) days following
delivery of a written request therefor by Indemnitee to the Company.

          (b) NOTICE/COOPERATION BY INDEMNITEE. Indemnitee shall, as a condition
precedent to his or her right to be indemnified under this Agreement, give the
Company notice in writing as soon as practicable of any claim made against
Indemnitee for which indemnification will or could be sought under this
Agreement. Notice to the Company shall be directed to the Chief Executive
Officer of the Company and shall be given in accordance with the provisions of
Section 12(d) below. In addition, Indemnitee shall give the Company such
information and cooperation as it may reasonably require and as shall be within
Indemnitee's power.

          (c) PROCEDURE. Any indemnification and advances provided for in
Section 1 and this Section 3 shall be made no later than forty-five (45) days
after receipt of the written request of Indemnitee. If a claim under this
Agreement, under any statute, or under any provision of the Company's
Certificate of Incorporation or Bylaws providing for indemnification, is not
paid in full by the Company within forty-five (45) days after a written request
for payment thereof has first been received by the Company, Indemnitee may, but
need not, at any time thereafter bring an action against the Company to recover
the unpaid amount of the claim and, subject to Section 11 of this Agreement,
Indemnitee shall also be entitled to be paid for the expenses (including
attorneys' fees) of bringing such action. It shall be a defense to any such
action (other than an action brought to enforce a claim for expenses incurred in
connection with any action, suit or proceeding in advance of its final
disposition) that Indemnitee has not met the standards of conduct which make it
permissible under applicable law for the Company to indemnify Indemnitee for the
amount claimed, but the burden of proving such defense shall be on the Company
and Indemnitee shall be entitled to receive interim payments of expenses
pursuant to Section 3(a) unless and until such defense may be finally
adjudicated by court order or judgment from which no further right of appeal
exists. It is the parties' intention that if the Company contests Indemnitee's
right to indemnification, the question of Indemnitee's right to indemnification
shall be for the court to decide, and neither the failure of the Company
(including its Board of Directors, any committee or subgroup of the Board of
Directors, independent legal counsel, or its stockholders) to have made a
determination that indemnification of Indemnitee is proper in the circumstances
because Indemnitee has met the applicable standard of conduct required by
applicable law, nor an actual determination by the Company (including its Board
of Directors, any committee or subgroup of the Board of Directors, independent
legal counsel, or its stockholders) that Indemnitee has not met such applicable
standard of conduct, shall create a presumption that Indemnitee has or has not
met the applicable standard of conduct.

          (d) NOTICE TO INSURERS. If, at the time of the receipt of a notice of
a claim pursuant to Section 3(b) hereof, the Company has director and officer
liability insurance in effect, the Company shall give prompt notice of the
commencement of such proceeding to the insurers in accordance with the
procedures set forth in the respective policies. The Company


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shall thereafter take all necessary or desirable action to cause such insurers
to pay, on behalf of the Indemnitee, all amounts payable as a result of such
proceeding in accordance with the terms of such policies.

          (e) SELECTION OF COUNSEL. In the event the Company shall be obligated
under Section 3(a) hereof to pay the expenses of any proceeding against
Indemnitee, the Company, if appropriate, shall be entitled to assume the defense
of such proceeding, with counsel approved by Indemnitee, upon the delivery to
Indemnitee of written notice of its election so to do. After delivery of such
notice, approval of such counsel by Indemnitee and the retention of such counsel
by the Company, the Company will not be liable to Indemnitee under this
Agreement for any fees of counsel subsequently incurred by Indemnitee with
respect to the same proceeding, provided that (i) Indemnitee shall have the
right to employ counsel in any such proceeding at Indemnitee's expense; and (ii)
if (A) the employment of counsel by Indemnitee has been previously authorized by
the Company, (B) Indemnitee shall have reasonably concluded that there may be a
conflict of interest between the Company and Indemnitee in the conduct of any
such defense or (C) the Company shall not, in fact, have employed counsel to
assume the defense of such proceeding, then the fees and expenses of
Indemnitee's counsel shall be at the expense of the Company.

     4.   ADDITIONAL INDEMNIFICATION RIGHTS; NONEXCLUSIVITY

          (a) SCOPE. Notwithstanding any other provision of this Agreement, the
Company hereby agrees to indemnify the Indemnitee to the fullest extent
permitted by law, notwithstanding that such indemnification is not specifically
authorized by the other provisions of this Agreement, the Company's Certificate
of Incorporation, the Company's Bylaws or by statute. In the event of any
change, after the date of this Agreement, in any applicable law, statute, or
rule which expands the right of a Delaware corporation to indemnify a member of
its board of directors or an officer, such changes shall be deemed to be within
the purview of Indemnitee's rights and the Company's obligations under this
Agreement. In the event of any change in any applicable law, statute or rule
which narrows the right of a Delaware corporation to indemnify a member of its
board of directors or an officer, such changes, to the extent not otherwise
required by such law, statute or rule to be applied to this Agreement shall have
no effect on this Agreement or the parties' rights and obligations hereunder.

          (b) NONEXCLUSIVITY. The indemnification provided by this Agreement
shall not be deemed exclusive of any rights to which Indemnitee may be entitled
under the Company's Certificate of Incorporation, its Bylaws, any agreement, any
vote of stockholders or disinterested members of the Company's Board of
Directors, the General Corporation Law of the State of Delaware, or otherwise,
both as to action in Indemnitee's official capacity and as to action in another
capacity while holding such office. The indemnification provided under this
Agreement shall continue as to Indemnitee for any action taken or not taken
while serving in an indemnified capacity even though he or she may have ceased
to serve in any such capacity at the time of any action, suit or other covered
proceeding.


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     5.   PARTIAL INDEMNIFICATION. If Indemnitee is entitled under any provision
of this Agreement to indemnification by the Company for some or a portion of the
expenses, judgments, fines or penalties actually or reasonably incurred in the
investigation, defense, appeal or settlement of any civil or criminal action,
suit or proceeding, but not, however, for the total amount thereof, the Company
shall nevertheless indemnify Indemnitee for the portion of such expenses,
judgments, fines or penalties to which Indemnitee is entitled.

     6.   MUTUAL ACKNOWLEDGMENT. Both the Company and Indemnitee acknowledge
that in certain instances, Federal law or public policy may override applicable
state law and prohibit the Company from indemnifying its directors and officers
under this Agreement or otherwise. For example, the Company and Indemnitee
acknowledge that the Securities and Exchange Commission (the "SEC") has taken
the position that indemnification is not permissible for liabilities arising
under certain federal securities laws, and federal legislation prohibits
indemnification for certain ERISA violations. Indemnitee understands and
acknowledges that the Company has undertaken or may be required in the future to
undertake with the SEC to submit the question of indemnification to a court in
certain circumstances for a determination of the Company's right under public
policy to indemnify Indemnitee.

     7.   OFFICER AND DIRECTOR LIABILITY INSURANCE. The Company shall, from time
to time, make the good faith determination whether or not it is practicable for
the Company to obtain and maintain a policy or policies of insurance with
reputable insurance companies providing the officers and directors of the
Company with coverage for losses from wrongful acts, or to ensure the Company's
performance of its indemnification obligations under this Agreement. Among other
considerations, the Company will weigh the costs of obtaining such insurance
coverage against the protection afforded by such coverage. In all policies of
director and officer liability insurance, Indemnitee shall be named as an
insured in such a manner as to provide Indemnitee the same rights and benefits
as are accorded to the most favorably insured of the Company's directors, if
Indemnitee is a director; or of the Company's officers, if Indemnitee is not a
director of the Company but is an officer; or of the Company's key employees, if
Indemnitee is not an officer or director but is a key employee. Notwithstanding
the foregoing, the Company shall have no obligation to obtain or maintain such
insurance if the Company determines in good faith that such insurance is not
reasonably available, if the premium costs for such insurance are
disproportionate to the amount of coverage provided, if the coverage provided by
such insurance is limited by exclusions so as to provide an insufficient
benefit, or if Indemnitee is covered by similar insurance maintained by a parent
or subsidiary of the Company.

     8.   SEVERABILITY. Nothing in this Agreement is intended to require or
shall be construed as requiring the Company to do or fail to do any act in
violation of applicable law. The Company's inability, pursuant to court order,
to perform its obligations under this Agreement shall not constitute a breach of
this Agreement. The provisions of this Agreement shall be severable as provided
in this Section 8. If this Agreement or any portion hereof shall be invalidated
on any ground by any court of competent jurisdiction, then the Company shall
nevertheless indemnify Indemnitee to the full extent permitted by any applicable
portion of this


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Agreement that shall not have been invalidated, and the balance of this
Agreement not so invalidated shall be enforceable in accordance with its terms.

     9.   EXCEPTIONS. Any other provision herein to the contrary
notwithstanding, the Company shall not be obligated pursuant to the terms of
this Agreement:

          (a) CLAIMS INITIATED BY INDEMNITEE. To indemnify or advance expenses
to Indemnitee with respect to proceedings or claims initiated or brought
voluntarily by Indemnitee and not by way of defense, except with respect to
proceedings brought to establish or enforce a right to indemnification under
this Agreement or any other statute or law or otherwise as required under
Section 145 of the Delaware General Corporation Law, but such indemnification or
advancement of expenses may be provided by the Company in specific cases if the
Board of Directors finds it to be appropriate;

          (b) LACK OF GOOD FAITH. To indemnify Indemnitee for any expenses
incurred by Indemnitee with respect to any proceeding instituted by Indemnitee
to enforce or interpret this Agreement, if a court of competent jurisdiction
determines that each of the material assertions made by Indemnitee in such
proceeding was not made in good faith or was frivolous;

          (c) INSURED CLAIMS. To indemnify Indemnitee for expenses or
liabilities of any type whatsoever (including, but not limited to, judgments,
fines, ERISA excise taxes or penalties, and amounts paid in settlement) to the
extent such expenses or liabilities have been paid directly to Indemnitee by an
insurance carrier under a policy of officers' and directors' liability insurance
maintained by the Company; or

          (d) CLAIMS UNDER SECTION 16(b). To indemnify Indemnitee for expenses
or the payment of profits arising from the purchase and sale by Indemnitee of
securities in violation of Section 16(b) of the Securities Exchange Act of 1934,
as amended, or any similar successor statute.

     10.  CONSTRUCTION OF CERTAIN PHRASES

          (a) For purposes of this Agreement, references to the "COMPANY" shall
include, in addition to the resulting corporation, any constituent corporation
(including any constituent of a constituent) absorbed in a consolidation or
merger which, if its separate existence had continued, would have had power and
authority to indemnify its directors, officers, and employees or agents, so that
if Indemnitee is or was a director, officer, employee or agent of such
constituent corporation, or is or was serving at the request of such constituent
corporation as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise, Indemnitee shall stand in
the same position under the provisions of this Agreement with respect to the
resulting or surviving corporation as Indemnitee would have with respect to such
constituent corporation if its separate existence had continued.


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          (b) For purposes of this Agreement, references to "OTHER ENTERPRISES"
shall include employee benefit plans; references to "FINES" shall include any
excise taxes assessed on Indemnitee with respect to an employee benefit plan;
and references to "SERVING AT THE REQUEST OF THE COMPANY" shall include any
service as a director, officer, employee or agent of the Company which imposes
duties on, or involves services by, such director, officer, employee or agent
with respect to an employee benefit plan, its participants, or beneficiaries;
and if Indemnitee acted in good faith and in a manner Indemnitee reasonably
believed to be in the interest of the participants and beneficiaries of an
employee benefit plan, Indemnitee shall be deemed to have acted in a manner "NOT
OPPOSED TO THE BEST INTERESTS OF THE COMPANY" as referred to in this Agreement.

     11.  ATTORNEYS' FEES. In the event that any action is instituted by
Indemnitee under this Agreement to enforce or interpret any of the terms hereof,
Indemnitee shall be entitled to be paid all court costs and expenses, including
reasonable attorneys' fees, incurred by Indemnitee with respect to such action,
unless as a part of such action, the court of competent jurisdiction determines
that each of the material assertions made by Indemnitee as a basis for such
action were not made in good faith or were frivolous. In the event of an action
instituted by or in the name of the Company under this Agreement or to enforce
or interpret any of the terms of this Agreement, Indemnitee shall be entitled to
be paid all court costs and expenses, including attorneys' fees, incurred by
Indemnitee in defense of such action (including with respect to Indemnitee's
counterclaims and cross-claims made in such action), unless as a part of such
action the court determines that each of Indemnitee's material defenses to such
action were made in bad faith or were frivolous.

     12.  MISCELLANEOUS

          (a) GOVERNING LAW. This Agreement and all acts and transactions
pursuant hereto and the rights and obligations of the parties hereto shall be
governed, construed and interpreted in accordance with the laws of the State of
Delaware, without giving effect to principles of conflict of law.

          (b) ENTIRE AGREEMENT; ENFORCEMENT OF RIGHTS. This Agreement sets forth
the entire agreement and understanding of the parties relating to the subject
matter herein and merges all prior discussions between them. No modification of
or amendment to this Agreement, nor any waiver of any rights under this
Agreement, shall be effective unless in writing signed by the parties to this
Agreement. The failure by either party to enforce any rights under this
Agreement shall not be construed as a waiver of any rights of such party.

          (c) CONSTRUCTION. This Agreement is the result of negotiations between
and has been reviewed by each of the parties hereto and their respective
counsel, if any; accordingly, this Agreement shall be deemed to be the product
of all of the parties hereto, and no ambiguity shall be construed in favor of or
against any one of the parties hereto.


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          (d) NOTICES. Any notice, demand or request required or permitted to be
given under this Agreement shall be in writing and shall be deemed sufficient
when delivered personally or sent by telegram or forty-eight (48) hours after
being deposited in the U.S. mail, as certified or registered mail, with postage
prepaid, and addressed to the party to be notified at such party's address as
set forth below or as subsequently modified by written notice.

          (e) COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original and all of which
together shall constitute one instrument.

          (f) SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon the
Company and its successors and assigns, and inure to the benefit of Indemnitee
and Indemnitee's heirs, legal representatives and assigns.

          (g) SUBROGATION. In the event of payment under this Agreement, the
Company shall be subrogated to the extent of such payment to all of the rights
of recovery of Indemnitee, who shall execute all documents required and shall do
all acts that may be necessary to secure such rights and to enable the Company
to effectively bring suit to enforce such rights.

                            [Signature Page Follows]



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     The parties hereto have executed this Agreement as of the day and year set
forth on the first page of this Agreement.

                                            ROSETTA INPHARMATICS, INC.

                                            By:_________________________________

                                            Title:______________________________

                                            Address:____________________________

AGREED TO AND ACCEPTED:

________________________________


________________________________
(Signature)


Address:   _____________________

           _____________________