KOSAN BIOSCIENCES INCORPORATED

                            INDEMNIFICATION AGREEMENT

         THIS INDEMNIFICATION AGREEMENT ("Agreement") is made as of this __ day
of ___________, 199__ by and between Kosan Biosciences Incorporated, a
California corporation (the "Company") and ____________ ("Indemnitee").

         WHEREAS, the Company and Indemnitee recognize the increasing
difficulty in obtaining directors' and officers' liability insurance, the
significant increases in the cost of such insurance and the general reductions
in the coverage of such insurance;

         WHEREAS, the Company and Indemnitee further recognize the substantial
increase in corporate litigation in general, subjecting officers and directors
to expensive litigation risks at the same time as the availability and coverage
of liability insurance has been severely limited;

         WHEREAS, Indemnitee does not regard the current protection available
as adequate under the present circumstances, and Indemnitee and other officers
and directors of the Company may not be willing to continue to serve as
officers and directors without additional protection; and

         WHEREAS, the Company desires to attract and retain the services of
highly qualified individuals, such as Indemnitee, to serve as officers and
directors of the Company and to indemnify its officers and directors so as to
provide them with the maximum protection permitted by law.

         NOW, THEREFORE, 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 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 or proceeding if Indemnitee acted
in good faith and in a manner Indemnitee believed to be in 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 or proceeding by judgment, order, settlement, conviction, or upon
a plea of NOLO CONTENDERE or its equivalent, shall not, of itself, create a
presump-



tion that (i) Indemnitee did not act in good faith and in a manner which
Indemnitee reasonably believed to be in the best interests of the Company, or
(ii) with respect to any criminal action or proceeding, 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, in each case to the extent
actually and reasonably incurred by Indemnitee in connection with the defense
or settlement of such action or proceeding if Indemnitee acted in good faith
and in a manner Indemnitee believed to be in the best interests of the Company
and its shareholders.

         2.   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 or proceeding referenced
in Section 1(a) or (b) hereof (but not amounts actually paid in settlement of
any such action or proceeding). Indemnitee hereby undertakes to repay such
amounts advanced only if, and to the extent that, it shall ultimately be
determined that Indemnitee is not entitled to be indemnified by the Company as
authorized hereby. The advances to be made hereunder 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 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 at the address shown on the signature page of this
Agreement (or such other address as the Company shall designate in writing to
Indemnitee). Notice shall be deemed received three business days after the date
postmarked if sent by domestic certified or registered mail, properly
addressed; otherwise notice shall be deemed received when such notice shall
actually be received by the Company. 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 provided for in Section 1
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 Articles 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,


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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 13 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 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, and Indemnitee shall be entitled to receive interim
payments of expenses pursuant to Subsection 2(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
shareholders) 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 shareholders) 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 2(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 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 2(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, which
approval shall not be unreasonably withheld, 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
his 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.


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         3.   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 Articles 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 California corporation to
indemnify a member of its board of directors, an officer or other corporate
agent, such changes shall be, IPSO FACTO, within the purview of Indemnitee's
rights and 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
California corporation to indemnify a member of its Board of Directors, an
officer or other corporate agent, such changes, to the extent required by such
law, statute or rule to be applied to this Agreement, shall have the effect on
this Agreement and the parties' rights and obligations hereunder as is required
by such law, statute or rule.

              (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 Articles of Incorporation, its Bylaws, any
agreement, any vote of shareholders or disinterested directors, the California
General Corporation Law, 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 may have ceased to serve in such capacity at the time
of any action or other covered proceeding.

         4.   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 by him in the investigation, defense, appeal or settlement of any
civil or criminal action 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.

         5.   MUTUAL ACKNOWLEDGMENT. Both the Company and Indemnitee
acknowledge that in certain instances, Federal law or applicable public policy
may prohibit the Company from indemnifying its directors and officers under
this Agreement or otherwise. Indemnitee understands and acknowledges that the
Company has undertaken or may be required in the future to undertake with the
Securities and Exchange Commission 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.

         6.   DIRECTORS' AND OFFICERS' 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


                                      -4-


considerations, the Company will weigh the costs of obtaining such insurance
coverage against the protection afforded by such coverage. In all policies of
directors' and officers' 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 subsidiary or parent of the Company.

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

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

              (a)   EXCLUDED ACTS. To indemnify Indemnitee for any acts or
omissions or transactions from which a director may not be relieved of
liability under the California General Corporation Law.

              (b)   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 317 of the California General Corporation Law, but
such indemnification or advancement of expenses may be provided by the Company
in specific cases if the Board of Directors has approved the initiation or
bringing of such suit; or

              (c)   LACK OF GOOD FAITH. To indemnify Indemnitee for any
expenses incurred by the 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 the
Indemnitee in such proceeding was not made in good faith or was frivolous; or


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              (d)   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) which
have been paid directly to Indemnitee by an insurance carrier under a policy of
directors' and officers' liability insurance maintained by the Company; or

              (e)   CLAIMS UNDER SECTION 16(b). To indemnify Indemnitee for
expenses and 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.

         9.   EFFECTIVENESS OF AGREEMENT. To the extent that the
indemnification permitted under the terms of certain provisions of this
Agreement exceeds the scope of the indemnification expressly permitted by
Section 317 of the California General Corporation Law, such provisions shall
not be effective unless and until the Company's Articles of Incorporation
authorize such additional rights of indemnification. In all other respects, the
balance of this Agreement shall be effective as of the date set forth on the
first page and may apply to acts or omissions of Indemnitee which occurred
prior to such date if Indemnitee was an officer, director, employee or other
agent of the Company, 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, at the time such act or omission occurred.

         10.  CONSTRUCTION OF CERTAIN PHRASES.

              (a)   For purposes of this Agreement, references to the "Company"
shall also 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, 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.

              (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.

         11.  COUNTERPARTS. This Agreement may be executed in one or
more counterparts, each of which shall constitute an original.


                                      -6-


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

         13.  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 costs and expenses,
including reasonable attorneys' fees, incurred by Indemnitee with respect to
such action, unless as a part of such action, a 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 costs and expenses, including reasonable 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.

         14.  NOTICE. All notices, requests, demands and other communications
under this Agreement shall be in writing and shall be deemed duly given (i) if
delivered by hand and receipted for by the party addressee, on the date of such
receipt, or (ii) if mailed by domestic certified or registered mail with
postage prepaid, on the third business day after the date postmarked. Addresses
for notice to either party are as shown on the signature page of this
Agreement, or as subsequently modified by written notice.

         15.  CONSENT TO JURISDICTION. The Company and Indemnitee each hereby
irrevocably consent to the jurisdiction of the courts of the State of
California for all purposes in connection with any action or proceeding which
arises out of or relates to this Agreement and agree that any action instituted
under this Agreement shall be brought only in the state courts of the State of
California.

         16.  CHOICE OF LAW. This Agreement shall be governed by and its
provisions construed in accordance with the laws of the State of California as
applied to contracts between California residents entered into and to be
performed entirely within California.

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

                                          KOSAN BIOSCIENCES INCORPORATED

                                          By:_________________________________
                                              Daniel V. Santi, President

         AGREED TO AND ACCEPTED:

         INDEMNITEE:

         ___________________________

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