KOSAN BIOSCIENCES INC
FORM OF LEVEL I CHANGE OF CONTROL AND SEVERANCE BENEFIT AGREEMENT
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<TYPE>EX-10.29
<SEQUENCE>5
<FILENAME>dex1029.htm
<DESCRIPTION>FORM OF LEVEL I CHANGE OF CONTROL AND SEVERANCE BENEFIT AGREEMENT
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<TITLE>Form of Level I Change of Control and Severance Benefit Agreement</TITLE>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2"><B>Exhibit 10.29 </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="right"><FONT
FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>KOSAN BIOSCIENCES INCORPORATED </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px"
ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>CHANGE IN CONTROL AND SEVERANCE BENEFIT AGREEMENT </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">This Change in Control and
Severance Benefit Agreement (the &#147;<B><I>Agreement</I></B>&#148;), by and between Kosan Biosciences Incorporated (the &#147;<B><I>Company</I></B>&#148;) and <U>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</U>
(&#147;<B><I>Employee</I></B>&#148;) is established effective <U>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</U> <U>&nbsp;&nbsp;&nbsp;&nbsp;</U>,
<U>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</U> (the &#147;<B><I>Effective Date</I></B>&#148;). The purpose of this Agreement is to provide for the payment of severance benefits to Employee in the event that Employee is subject to a
qualifying employment termination in connection with a Change in Control. This Agreement shall supersede any severance benefit plan, policy or practice previously maintained by the Company relating to change in control benefits and any individually
negotiated contract or agreement between Employee and the Company relating to change in control benefits. Since this Agreement, together with other similar agreements with other employees of the Company, will constitute an &#147;employee benefit
plan&#148; under ERISA, this document also is a summary plan description. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 1. D<SMALL>EFINITIONS</SMALL>. </B></FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">For purposes of the Agreement, the following terms are defined as follows: </FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2"><B>(a) </B><B><I>&#147;Base Salary&#148;</I></B> means Employee&#146;s annual base pay (excluding incentive pay, premium pay, commissions, overtime, bonuses and other forms of variable compensation), at the rate in
effect during the last regularly scheduled payroll period immediately preceding the date of Employee&#146;s Covered Termination. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(b)
</B><B><I>&#147;Board&#148;</I></B> means the Board of Directors of Kosan Biosciences Incorporated. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(c) </B><B><I>&#147;Change in
Control&#148;</I></B> means the occurrence, in a single transaction or in a series of related transactions, of any one or more of the following events: </FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:8%"><FONT
FACE="Times New Roman" SIZE="2"><B>(i) </B>any Exchange Act Person becomes the Owner, directly or indirectly, of securities of the Company representing more than fifty percent (50%)&nbsp;of the combined voting power of the Company&#146;s then
outstanding securities other than by virtue of a merger, consolidation or similar transaction. Notwithstanding the foregoing, a Change in Control shall not be deemed to occur (A)&nbsp;on account of the acquisition of securities of the Company by an
investor, any affiliate thereof or any other Exchange Act Person from the Company in a transaction or series of related transactions the primary purpose of which is to obtain financing for the Company through the issuance of equity securities or
(B)&nbsp;solely because the level of Ownership held by any Exchange Act Person (the &#147;<B><I>Subject Person</I></B>&#148;) exceeds the designated percentage threshold of the outstanding voting securities as a result of a repurchase or other
acquisition of voting securities by the Company reducing the number of shares outstanding, <I>provided</I> that if a Change in Control would occur (but for the operation of this sentence) as a result of the acquisition of voting securities by the
Company, and after such share acquisition, the Subject Person becomes the Owner of any additional voting securities that, assuming the repurchase or other acquisition had not occurred, increases the percentage of the then outstanding voting
securities Owned by the Subject Person over the designated percentage threshold, then a Change in Control shall be deemed to occur; </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">1.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(ii) </B>there is consummated a merger, consolidation or similar transaction involving (directly
or indirectly) the Company and, immediately after the consummation of such merger, consolidation or similar transaction, the stockholders of the Company immediately prior thereto do not Own, directly or indirectly, either (A)&nbsp;outstanding voting
securities representing more than fifty percent (50%)&nbsp;of the combined outstanding voting power of the surviving Entity in such merger, consolidation or similar transaction or (B)&nbsp;more than fifty percent (50%)&nbsp;of the combined
outstanding voting power of the parent of the surviving Entity in such merger, consolidation or similar transaction, in each case in substantially the same proportions as their Ownership of the outstanding voting securities of the Company
immediately prior to such transaction; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(iii) </B>the stockholders of the Company approve or the Board approves a plan of complete
dissolution or liquidation of the Company, or a complete dissolution or liquidation of the Company shall otherwise occur; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(iv)
</B>there is consummated a sale, lease, exclusive license or other disposition of all or substantially all of the consolidated assets of the Company and its Subsidiaries, other than a sale, lease, license or other disposition of all or substantially
all of the consolidated assets of the Company and its Subsidiaries to an Entity, more than fifty percent (50%)&nbsp;of the combined voting power of the voting securities of which are Owned by stockholders of the Company in substantially the same
proportions as their Ownership of the outstanding voting securities of the Company immediately prior to such sale, lease, license or other disposition; or </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT
FACE="Times New Roman" SIZE="2"><B>(v) </B>individuals who, on the Effective Date, are members of the Board (the &#147;<B><I>Incumbent Board</I></B>&#148;) cease for any reason to constitute at least a majority of the members of the Board;
<I>provided, however,</I> that if the appointment or election (or nomination for election) of any new Board member was approved or recommended by a majority vote of the members of the Incumbent Board then still in office, such new member shall, for
purposes of this Agreement, be considered as a member of the Incumbent Board. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">The term Change in Control shall not include a sale of assets, merger or
other transaction effected exclusively for the purpose of changing the domicile of the Company. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(d) </B><B><I>&#147;Code&#148;
</I></B>means the Internal Revenue Code of 1986, as amended. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(e) </B><B><I>&#147;Company&#148;</I></B> means Kosan Biosciences
Incorporated and its wholly owned Subsidiaries or, following a Change in Control, the surviving entity resulting from such transaction. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman"
SIZE="2"><B>(f) </B><B><I>&#147;Constructive Termination&#148;</I></B> means a voluntary termination of employment by Employee after one of the following is undertaken without Employee&#146;s express written consent: </FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(i) </B>a substantial reduction in Employee&#146;s duties or responsibilities (and not simply a change in title or reporting relationships) in effect
immediately prior to the effective date of the Change in Control; <I>provided, however,</I> that it shall not be a &#147;Constructive </FONT>
</P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">2.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px">
<FONT FACE="Times New Roman" SIZE="2">Termination&#148; if, following the effective date of the Change in Control, Employee holds a position with duties and responsibilities comparable (though
not necessarily identical, in view of the relative sizes of the Company and the entity involved in the Change in Control) to the duties and responsibilities of Employee immediately prior to the effective date of the Change in Control; and
<I>provided, further,</I> that if Employee is serving as the Company&#146;s Chief Executive Officer immediately prior to the effective date of the Change in Control, a &#147;Constructive Termination&#148; shall occur if Employee does not hold
following the Effective Date of the Change in Control a position as an executive officer of the &#147;parent&#148; surviving Entity of the Change in Control; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT
FACE="Times New Roman" SIZE="2"><B>(ii) </B>a reduction in Employee&#146;s annual base salary (except for salary decreases generally applicable to all Company executives); </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(iii) </B>a material reduction in Employee&#146;s package of benefits and incentives (except for changes generally applicable to all Company
executives); </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(iv) </B>a change in Employee&#146;s business location of more than 35 miles from the business location prior to such
change, except for required travel for the Company&#146;s business to an extent substantially consistent with Employee&#146;s prior business travel obligations; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT
FACE="Times New Roman" SIZE="2"><B>(v) </B>a material breach by the Company of any provisions of the Agreement or any enforceable written agreement between the Company and Employee; or </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(vi) </B>any failure by the Company to obtain assumption of the Agreement by any successor or assign of the Company. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">Notwithstanding the foregoing, a voluntary termination shall not be deemed a Constructive Termination unless (x)&nbsp;Employee provides the Company with
written notice (the &#147;<B><I>Constructive Termination Notice</I></B>&#148;) that Employee believes that an event described in this Section&nbsp;1(f) has occurred, (y)&nbsp;the Constructive Termination Notice is given within three (3)&nbsp;months
following the date the event occurred and (z)&nbsp;the Company does not rescind or cure the conduct giving rise to the event described in this Section&nbsp;1(f) within fifteen (15)&nbsp;days following receipt by the Company of the Constructive
Termination Notice. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(g) </B><B><I>&#147;Covered Termination&#148;</I></B> means an Involuntary Termination Without Cause or a
Constructive Termination, either of which occurs within one (1)&nbsp;month prior to or within eighteen (18)&nbsp;months following the effective date of a Change in Control; <I>provided, however,</I> that clause (i)&nbsp;of Section&nbsp;1(f) shall
not apply prior to a Change in Control. Termination of employment of Employee due to death or disability shall not constitute a Covered Termination unless a voluntary termination of employment by Employee immediately prior to Employee&#146;s death
or disability would have qualified as a Constructive Termination. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(h) </B><B><I>&#147;Entity&#148;</I></B> means a corporation,
partnership or other entity. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(i) </B><B><I>&#147;ERISA&#148; </I></B>means the Employee Retirement Income Security Act of 1974, as
amended. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(j) </B><B><I>&#147;Exchange Act&#148;</I></B> means the Securities Exchange Act of 1934, as amended. </FONT></P> <P
STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">3.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(k) </B><B><I>&#147;Exchange Act Person&#148; </I></B>means any natural person, Entity or
&#147;group&#148; (within the meaning of Section&nbsp;13(d) or 14(d) of the Exchange Act), except that &#147;Exchange Act Person&#148; shall not include (i)&nbsp;the Company or any Subsidiary of the Company; (ii)&nbsp;any employee benefit plan of
the Company or any Subsidiary of the Company or any trustee or other fiduciary holding securities under an employee benefit plan of the Company or any Subsidiary of the Company; (iii)&nbsp;an underwriter temporarily holding securities pursuant to an
offering of such securities; (iv)&nbsp;an Entity Owned, directly or indirectly, by the stockholders of the Company in substantially the same proportions as their Ownership of stock of the Company; or (v)&nbsp;any natural person, Entity or
&#147;group&#148; (within the meaning of Section&nbsp;13(d) or 14(d) of the Exchange Act) that, as of the Effective Date, is the Owner, directly or indirectly, of securities of the Company representing more than fifty percent (50%)&nbsp;of the
combined voting power of the Company&#146;s then outstanding securities. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(l) </B><B><I>&#147;Involuntary Termination Without
Cause&#148;</I></B> means an involuntary termination of employment by the Company other than for one of the following reasons: </FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(i)
</B>Employee&#146;s violation of any material provision of the Company&#146;s standard agreement relating to proprietary rights which is not cured within 30 days after written notice of violation (if the violation is reasonably susceptible of being
cured); </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(ii) </B>Employee&#146;s conviction of a felony or crime involving moral turpitude; </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(iii) </B>Employee participates in any act of theft, dishonesty, fraud, or willful neglect, misconduct or misrepresentation in connection with, or in
the course of, carrying out Employee&#146;s duties and responsibilities; or </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(iv) </B>Employee&#146;s insubordination or refusal to
perform reasonable and lawful directives from Employee&#146;s superiors, which Employee fails to correct within 15 days after written notice (if such conduct is reasonably susceptible of being cured). </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(m) </B><B><I>&#147;Own,&#148; &#147;Owned,&#148; &#147;Owner,&#148; &#147;Ownership&#148;</I></B><B> </B>A person or Entity shall be deemed to
&#147;Own,&#148; to have &#147;Owned,&#148; to be the &#147;Owner&#148; of, or to have acquired &#147;Ownership&#148; of securities if such person or Entity, directly or indirectly, through any contract, arrangement, understanding, relationship or
otherwise, has or shares voting power, which includes the power to vote or to direct the voting, with respect to such securities. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(n)
</B><B><I>&#147;Plan&#148; </I></B>means this Agreement, together with other similar agreements with other employees of the Company, as amended from time to time. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2"><B>(o) </B><B><I>&#147;Subsidiary&#148;</I></B> means, with respect to the Company, (i)&nbsp;any corporation of which more than fifty percent (50%)&nbsp;of the outstanding capital stock having ordinary voting power to
elect a majority of the board of directors of such corporation (irrespective of whether, at the time, stock of any other class or classes of such corporation shall have or might have voting power by reason of the happening of any contingency) is at
the time, directly or indirectly, Owned by the Company, and (ii)&nbsp;any partnership in which the Company has a direct or indirect interest (whether in the form of voting or participation in profits or capital contribution) of more than fifty
percent (50%). </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">4.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 2. E<SMALL>LIGIBILITY</SMALL> F<SMALL>OR</SMALL> B<SMALL>ENEFITS</SMALL>. </B></FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(a) General Rules.</B> Subject to the provisions set forth in this Section and Section&nbsp;6, in the event of a Covered Termination, the Company will
provide the severance benefits described in Section&nbsp;3 of the Agreement to Employee. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(b) Exceptions to Benefit Entitlement.</B>
Employee will not receive benefits under this Agreement in the following circumstances, as determined by the Company in its sole discretion: </FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman"
SIZE="2"><B>(i) </B>Employee voluntarily terminates employment with the Company in order to accept employment with another entity that is controlled (directly or indirectly) by the Company or is otherwise an affiliate of the Company; </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(ii) </B>Employee is offered immediate reemployment by a successor to the Company or by a purchaser of its assets, as the case may be, following a
change in the ownership of the Company or a sale of all or substantially all the assets of a division or business unit of the Company. For purposes of the foregoing, &#147;immediate reemployment&#148; means that Employee&#146;s employment with the
successor to the Company or the purchaser of its assets, as the case may be, results in uninterrupted employment such that Employee suffers neither (i)&nbsp;a substantial reduction in Employee&#146;s duties or responsibilities (and not simply a
change in title or reporting relationships) in effect immediately prior to the effective date of the Change in Control, nor (ii)&nbsp;a lapse in pay as a result in the change in ownership of the Company or the sale of its assets; or </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(iii) </B>Employee does not confirm in writing that [he][she] shall be subject to the Company&#146;s Employee Proprietary Information and Invention
Assignment Agreement. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(c) Termination of Benefits.</B> Employee&#146;s right to receive the payment of benefits under this Agreement
shall terminate immediately if, at any time prior to or during the period for which Employee is receiving benefits hereunder, Employee, without the prior written approval of the Company: </FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(i) </B>willfully breaches a material provision of Employee&#146;s proprietary information or confidentiality agreement with the Company, as referenced
in Section&nbsp;3(b)(iv); </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(ii) </B>encourages or solicits any of the Company&#146;s then current employees to leave the Company&#146;s
employ for any reason or interferes in any other manner with employment relationships at the time existing between the Company and its then current employees; or </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT
FACE="Times New Roman" SIZE="2"><B>(iii) </B>induces any of the Company&#146;s then current clients, customers, suppliers, vendors, distributors, licensors, licensees or other third party to terminate their existing business relationship with the
Company or interferes in any other manner with any existing business relationship between the Company and any then current client, customer, supplier, vendor, distributor, licensor, licensee or other third party. </FONT></P> <P
STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">5.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 3. A<SMALL>MOUNT</SMALL> <SMALL>OF</SMALL> B<SMALL>ENEFITS</SMALL>. </B></FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(a) Cash Severance Benefits.</B> In the event Employee incurs a Covered Termination and was employed by the Company in the position of
<U>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</U> of the Company within one (1)&nbsp;month immediately prior to such Covered Termination, Employee shall be entitled to
receive a cash severance benefit equal to (i)&nbsp;two (2)&nbsp;times Employee&#146;s Base Salary, plus (ii)&nbsp;two (2)&nbsp;times the greatest of (a)&nbsp;the cash bonus paid to Employee in the year prior to the Covered Termination, (b)&nbsp;the
target cash bonus to be paid to Employee in the year in which the Covered Termination occurs, and (c)&nbsp;the target cash bonus as in effect immediately prior to the Change in Control. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(b) Accelerated Stock Award Vesting and Extended Exercisability of Stock Options.</B> If Employee incurs a Covered Termination, then effective as of
the date of Employee&#146;s Covered Termination, (i)&nbsp;the vesting and exercisability of all outstanding options to purchase the Company&#146;s common stock that are held by Employee on such date shall be accelerated in full, and (ii)&nbsp;any
reacquisition or repurchase rights held by the Company in respect of common stock issued pursuant to any other stock award granted to Employee by the Company shall lapse. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2">In addition, the post-termination of employment exercise period of any outstanding option held by Employee on the date of [his][her] Covered Termination shall be extended, if necessary, such that the post-termination
of employment exercise period shall not terminate prior to the later of (i)&nbsp;the date twelve (12)&nbsp;months after the effective date of the Covered Termination and (ii)&nbsp;the post-termination exercise period provided for in such option;
<I>provided, however</I>, that such option shall not be exercisable after the expiration of its maximum term; <I>provided, further, however</I>, that in the event that any extended exercisability of an option pursuant to this Section&nbsp;4(b) would
adversely affect Employee&#146;s option or other stock award (including, without limitation, its status as an incentive stock option under Section&nbsp;422 of the Code or result in an option that would not otherwise be deemed to be a nonqualified
deferred compensation plan or arrangement for the purposes of Section&nbsp;409A of the Code to be deemed to be such a nonqualified deferred compensation plan or arrangement), such extended exercisability shall be deemed null and void unless Employee
consents in writing to such extended exercisability. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(c) Continued Medical Benefits</B>. If Employee incurs a Covered Termination and
Employee was enrolled in a health, dental, or vision plan sponsored by the Company immediately prior to such Covered Termination, Employee may be eligible to continue coverage under such health, dental, or vision plan (or to convert to an individual
policy), at the time of Employee&#146;s termination of employment, under the Consolidated Omnibus Budget Reconciliation Act of 1985 (&#147;<B><I>COBRA</I></B>&#148;). The Company will notify Employee of any such right to continue such coverage at
the time of termination pursuant to COBRA. No provision of this Agreement will affect the continuation coverage rules under COBRA, except that the Company&#146;s payment, if any, of applicable insurance premiums will be credited as payment by the
Employee for purposes of Employee&#146;s payment required under COBRA. Therefore, the period during which Employee may elect to continue the Company&#146;s health, dental, or vision plan coverage at [his][her] own expense under COBRA, the length of
time during which COBRA coverage will be made available to Employee, and all other rights and obligations of Employee under COBRA (except the obligation to pay insurance premiums that the Company pays, if any) will be applied in the same manner that
such rules would apply in the absence of this Agreement. </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">6.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">If Employee timely elects continued coverage under COBRA, the Company shall pay the full amount of
the Employee&#146;s COBRA premiums on behalf of Employee for Employee&#146;s continued coverage under the Company&#146;s health, dental and vision plans, including coverage for Employee&#146;s eligible dependents, for a period of 24 months (the
&#147;<B><I>Severance Period</I></B>&#148;); <I>provided, however,</I> that if the Severance Period exceeds the length of time that the Employee is entitled to coverage under COBRA, the resulting or acquiring entity or Transferee Corporation
involved in the Change in Control, as applicable, shall be required to provide health, dental and vision insurance coverage for Employee and [his][her] eligible dependents for any portion of the Severance Period that exceeds the length of time that
Employee is entitled to coverage under COBRA, at a level of coverage that is substantially similar to the continued coverage that Employee and [his][her] eligible dependents received under the Company&#146;s health, dental and vision plans;
<I>provided, further, however, </I>that no such premium payments (or any other payments for medical, dental or vision coverage by the Company) shall be made following Employee&#146;s death or the effective date of Employee&#146;s coverage by a
medical, dental or vision insurance plan of a subsequent employer. Employee shall be required to notify the Company immediately if Employee becomes covered by a medical, dental or vision insurance plan of a subsequent employer. Upon the conclusion
of such period of insurance premium payments made by the Company, Employee will be responsible for the entire payment of premiums required under COBRA for the duration of the COBRA period. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">For purposes of this Section&nbsp;3(c), (i)&nbsp;references to COBRA shall be deemed to refer also to analogous provisions of state law and (ii)&nbsp;any
applicable insurance premiums that are paid by the Company shall not include any amounts payable by Employee under an Internal Revenue Code Section&nbsp;125 health care reimbursement plan, which amounts, if any, are the sole responsibility of
Employee. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(d) Other Employee Benefits. </B>All other benefits (such as life insurance, disability coverage, and 401(k) plan coverage)
shall terminate as of Employee&#146;s termination date (except to the extent that a conversion privilege may be available thereunder). </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 4.
T<SMALL>IME</SMALL> <SMALL>AND</SMALL> F<SMALL>ORM</SMALL> O<SMALL>F</SMALL> S<SMALL>EVERANCE</SMALL> P<SMALL>AYMENTS</SMALL>. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(a)
General Rules.</B> Subject to Section&nbsp;4(b), any cash severance benefit provided under Section&nbsp;3(a) shall be paid in one lump sum as soon as practicable, but no later than ten (10)&nbsp;days following the effective date of Employee&#146;s
Covered Termination and shall be subject to all applicable withholding for federal, state and local taxes. In no event shall payment of any Plan benefit be made prior to the effective date of Employee&#146;s Covered Termination or prior to the
effective date of the release described in Section&nbsp;6(a). </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(b) Application of Section&nbsp;409A. </B>In the event that any cash
severance benefit provided under Section&nbsp;3(a) or continued medical benefit under Section&nbsp;3(c) shall fail to satisfy the distribution requirement of Section&nbsp;409A(a)(2)(A) of the Code as a result of the application of
Section&nbsp;409A(a)(2)(B)(i) of the Code, the payment of such benefit shall be accelerated to the minimum extent necessary so that the benefit is not subject to the provisions of Section&nbsp;409A(a)(1) of the Code. (The payment schedule as revised
after the application of the preceding sentence shall be referred to as the &#147;<B><I>Revised Payment Schedule.</I></B>&#148;) In the event the payment of benefits pursuant to the Revised Payment Schedule would be subject to
Section&nbsp;409A(a)(1) of the Code, the payment of such benefits shall not be paid pursuant to the Revised Payment </FONT>
</P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">7.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px">
<FONT FACE="Times New Roman" SIZE="2">Schedule and instead the payment of such benefits shall be delayed to the minimum extent necessary so that such benefits are not subject to the provisions of
Section&nbsp;409A(a)(1) of the Code. The Board may attach conditions to or adjust the amounts paid pursuant to this Section&nbsp;4(b) to preserve, as closely as possible, the economic consequences that would have applied in the absence of this
Section&nbsp;4(b); <I>provided, however</I>, that no such condition or adjustment shall result in the payments being subject to Section&nbsp;409A(a)(1) of the Code. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2"><B>(c) Gross-Up.</B> If any payment, distribution or benefit Employee would receive from the Company pursuant to this Agreement, but determined without regard to any additional payment required under this section
4(c), pursuant to this Agreement (&#147;<B><I>Payment</I></B>&#148;), would (i)&nbsp;constitute a &#147;parachute payment&#148; within the meaning of Section&nbsp;280G of the Internal Revenue Code of 1986, as amended (the &#147;Code&#148;), and
(ii)&nbsp;be subject to the excise tax imposed by Section&nbsp;4999 of the Code or any interest or penalties payable with respect to such excise tax (such excise tax, together with any such interest and penalties, are hereinafter collectively
referred to as the &#147;<B><I>Excise Tax</I></B>&#148;), then Employee shall be entitled to receive from the Company an additional payment (the &#147;<B><I>Gross-Up Payment</I></B>&#148;) in an amount that shall fund the payment by Employee of any
Excise Tax on the Payment as well as all income and employment taxes imposed on the Gross-Up Payment, any Excise Tax imposed on the Gross-Up Payment and any interest or penalties imposed with respect to income and employment taxes imposed on the
Gross-Up Payment. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">The accounting firm engaged by the Company for general audit purposes as of the day prior to the effective date of the
Change in Control shall perform the foregoing calculations. If the accounting firm so engaged by the Company is serving as accountant or auditor for the individual, entity or group effecting the Change in Control, the Company shall appoint a
nationally recognized accounting firm to make the determinations required hereunder. The Company shall bear all expenses with respect to the determinations by such accounting firm required to be made hereunder. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">The accounting firm engaged to make the determinations hereunder shall provide its calculations, together with detailed supporting documentation, to the
Company and Employee within fifteen (15)&nbsp;calendar days after the date on which Employee&#146;s right to a Payment is triggered (if requested at that time by the Company or Employee) or such other time as requested by the Company or Employee. If
the accounting firm determines that no Excise Tax is payable with respect to a Payment, it shall furnish the Company and Employee with an opinion reasonably acceptable to Employee that no Excise Tax will be imposed with respect to such Payment. Any
good faith determinations of the accounting firm made hereunder shall be final, binding and conclusive upon the Company and Employee. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 5.
L<SMALL>IMITATIONS</SMALL> <SMALL>ON</SMALL> B<SMALL>ENEFITS</SMALL>. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(a) Release.</B> In order to be eligible to receive benefits
under the Plan, Employee also must execute a general waiver and release in substantially the form attached hereto as Exhibit A or Exhibit B, as applicable, and such release must become effective in accordance with its terms. For purposes of the
preceding sentence, with respect to any outstanding option held by Employee, the receipt of benefits shall be deemed to be the exercise of such option pursuant to the extended exercisability of such option under Section&nbsp;3(b), rather than the
acceleration or </FONT>
</P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">8.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px">
<FONT FACE="Times New Roman" SIZE="2">extension of such option&#146;s exercisability. The Company, in its sole discretion, may modify the form of the required release to comply with applicable
law and shall determine the form of the required release, which may be incorporated into a termination agreement or other agreement with Employee. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman"
SIZE="2"><B>(b) Certain Reductions.</B> The Company, in its sole discretion, shall have the authority to reduce Employee&#146;s severance benefits, in whole or in part, by any other severance benefits, pay in lieu of notice, or other similar
benefits payable to Employee by the Company that become payable in connection with Employee&#146;s termination of employment pursuant to (i)&nbsp;any applicable legal requirement, including, without limitation, the Worker Adjustment and Retraining
Notification Act (the &#147;<B><I>WARN Act</I></B>&#148;), (ii)&nbsp;a written employment or severance agreement with the Company, or (iii)&nbsp;any Company policy or practice providing for Employee to remain on the payroll for a limited period of
time after being given notice of the termination of Employee&#146;s employment. The benefits provided under this Agreement are intended to satisfy, in whole or in part, any and all statutory obligations and other contractual obligations of the
Company that may arise out of Employee&#146;s termination of employment, and the Plan Administrator shall so construe and implement the terms of the Agreement. The Company&#146;s decision to apply such reductions to the severance benefits of
Employee and the amount of such reductions shall in no way obligate the Company to apply the same reductions in the same amounts to the severance benefits of any other employee, even if similarly situated. In the Company&#146;s sole discretion, such
reductions may be applied on a retroactive basis, with severance benefits previously paid being recharacterized as payments pursuant to the Company&#146;s statutory or other contractual obligations. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(c) Mitigation.</B> Except as otherwise specifically provided herein, Employee shall not be required to mitigate damages or the amount of any payment
provided under this Plan by seeking other employment or otherwise, nor shall the amount of any payment provided for under this Agreement be reduced by any compensation earned by Employee as a result of employment by another employer or any
retirement benefits received by Employee after the date of Employee&#146;s termination of employment with the Company. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(d)
Non-Duplication of Benefits.</B> Except as otherwise specifically provided for herein, Employee is not eligible to receive benefits under this Agreement and pursuant to other contractual obligations more than one time. This Agreement is designed to
provide certain severance pay and change in control benefits to Employee pursuant to the terms and conditions set forth in this Agreement. The payments pursuant to this Agreement are in addition to, and not in lieu of, any unpaid salary, bonuses or
benefits to which Employee may be entitled for the period ending with Employee&#146;s Covered Termination. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(e) Indebtedness of
Employees. </B>If Employee is indebted to the Company on the effective date of [his][her] Covered Termination, the Company reserves the right to offset any severance payments under the Agreement by the amount of such indebtedness. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 6. R<SMALL>IGHT</SMALL> T<SMALL>O</SMALL> I<SMALL>NTERPRET</SMALL> P<SMALL>LAN</SMALL>; A<SMALL>MENDMENT</SMALL> <SMALL>AND</SMALL>
T<SMALL>ERMINATION</SMALL>. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(a) Exclusive Discretion.</B> The Company shall have the exclusive discretion and authority to establish
rules, forms, and procedures for the administration of the Plan and to </FONT>
</P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">9.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px">
<FONT FACE="Times New Roman" SIZE="2">construe and interpret the Plan and to decide any and all questions of fact, interpretation, definition, computation or administration arising in connection
with the operation of the Plan, including, but not limited to, the eligibility to participate in the Plan and amount of benefits paid under the Plan. The rules, interpretations, computations and other actions of the Company shall be binding and
conclusive on all persons. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(b) Amendment or Termination.</B> Any action amending or terminating the Agreement shall be in writing and
executed by each of Employee and a duly authorized officer of the Company. Unless otherwise required by law, no approval of the stockholders of the Company shall be required for any amendment or termination including any amendment that increases the
benefits provided under any option or other stock award. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 7. N<SMALL>O</SMALL> I<SMALL>MPLIED</SMALL> E<SMALL>MPLOYMENT</SMALL>
C<SMALL>ONTRACT</SMALL>. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">This Agreement shall not be deemed (i)&nbsp;to give Employee any right to be retained in the employ of the
Company or (ii)&nbsp;to interfere with the right of the Company to discharge Employee at any time, with or without cause, which right is hereby reserved. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman"
SIZE="2"><B>SECTION 8. L<SMALL>EGAL</SMALL> C<SMALL>ONSTRUCTION</SMALL>. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">This Agreement shall be governed by and construed under the
laws of the State of California (without regard to principles of conflict of laws), except to the extent preempted by ERISA. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 9.
C<SMALL>LAIMS</SMALL>, I<SMALL>NQUIRIES</SMALL> A<SMALL>ND</SMALL> A<SMALL>PPEALS</SMALL>. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(a) Applications for Benefits and
Inquiries.</B> Any application for benefits, inquiries about the Plan or inquiries about present or future rights under the Plan must be submitted to the Plan Administrator in writing by an applicant (or [his][her] authorized representative). The
Plan Administrator is: </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="2">Attn: Senior Vice President/General Counsel </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">3832 Bay Center Place </FONT></P> <P
STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">Hayward, CA 94545 </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(b) Denial of
Claims.</B> In the event that any application for benefits is denied in whole or in part, the Plan Administrator must provide the applicant with written or electronic notice of the denial of the application, and of the applicant&#146;s right to
review the denial. Any electronic notice will comply with the regulations of the U.S. Department of Labor. The notice of denial will be set forth in a manner designed to be understood by the applicant and will include the following: </FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(i) </B>the specific reason or reasons for the denial; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT
FACE="Times New Roman" SIZE="2"><B>(ii) </B>references to the specific Plan provisions upon which the denial is based; </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">10.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(iii) </B>a description of any additional information or material that the Plan Administrator
needs to complete the review and an explanation of why such information or material is necessary; and </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(iv) </B>an explanation of the
Plan&#146;s review procedures and the time limits applicable to such procedures, including a statement of the applicant&#146;s right to bring a civil action under Section&nbsp;502(a) of ERISA following a denial on review of the claim, as described
in Section&nbsp;11(d) below. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">This notice of denial will be given to the applicant within ninety (90)&nbsp;days after the Plan
Administrator receives the application, unless special circumstances require an extension of time, in which case, the Plan Administrator has up to an additional ninety (90)&nbsp;days for processing the application. If an extension of time for
processing is required, written notice of the extension will be furnished to the applicant before the end of the initial ninety (90)&nbsp;day period. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2">This notice of extension will describe the special circumstances necessitating the additional time and the date by which the Plan Administrator is to render its decision on the application. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(c) Request for a Review.</B> Any person (or that person&#146;s authorized representative) for whom an application for benefits is denied, in whole or
in part, may appeal the denial by submitting a request for a review to the Plan Administrator within sixty (60)&nbsp;days after the application is denied. A request for a review shall be in writing and shall be addressed to: </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">Attn: Senior
Vice President/General Counsel </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">3832 Bay Center Place </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="2">Hayward, CA 94545 </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">A request for review must set forth all of the grounds on which it is based, all facts
in support of the request and any other matters that the applicant feels are pertinent. The applicant (or [his][her] representative) shall have the opportunity to submit (or the Plan Administrator may require the applicant to submit) written
comments, documents, records, and other information relating to [his][her] claim. The applicant (or [his][her] representative) shall be provided, upon request and free of charge, reasonable access to, and copies of, all documents, records and other
information relevant to [his][her] claim. The review shall take into account all comments, documents, records and other information submitted by the applicant (or [his][her] representative) relating to the claim, without regard to whether such
information was submitted or considered in the initial benefit determination. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(d) Decision on Review.</B> The Plan Administrator will
act on each request for review within sixty (60)&nbsp;days after receipt of the request, unless special circumstances require an extension of time (not to exceed an additional sixty (60)&nbsp;days), for processing the request for a review. If an
extension for review is required, written notice of the extension will be furnished to the applicant within the initial sixty (60)&nbsp;day period. This notice of extension will describe the special circumstances necessitating the additional time
and the date by which the Plan Administrator is to render its decision on the review. The Plan Administrator will give prompt, </FONT>
</P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">11.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px">
<FONT FACE="Times New Roman" SIZE="2">written or electronic notice of its decision to the applicant. Any electronic notice will comply with the regulations of the U.S. Department of Labor. In the
event that the Plan Administrator confirms the denial of the application for benefits in whole or in part, the notice will set forth, in a manner calculated to be understood by the applicant, the following: </FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(i) </B>the specific reason or reasons for the denial; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT
FACE="Times New Roman" SIZE="2"><B>(ii) </B>references to the specific Plan provisions upon which the denial is based; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(iii) </B>a
statement that the applicant is entitled to receive, upon request and free of charge, reasonable access to, and copies of, all documents, records and other information relevant to [his][her] claim; and </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT FACE="Times New Roman" SIZE="2"><B>(iv) </B>a statement of the applicant&#146;s right to bring a civil action under Section&nbsp;502(a) of ERISA. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(e) Rules and Procedures.</B> The Plan Administrator will establish rules and procedures, consistent with the Plan and with ERISA, as necessary and
appropriate in carrying out its responsibilities in reviewing benefit claims. The Plan Administrator may require an applicant who wishes to submit additional information in connection with an appeal from the denial of benefits to do so at the
applicant&#146;s own expense. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(f) Exhaustion of Remedies.</B> No legal action for benefits under the Plan may be brought until the
applicant (i)&nbsp;has submitted a written application for benefits in accordance with the procedures described by Section&nbsp;11(a) above, (ii)&nbsp;has been notified by the Plan Administrator that the application is denied, (iii)&nbsp;has filed a
written request for a review of the application in accordance with the appeal procedure described in Section&nbsp;11(c) above, and (iv)&nbsp;has been notified that the Plan Administrator has denied the appeal. Notwithstanding the foregoing, if the
Plan Administrator does not respond to an applicant&#146;s claim or appeal within the relevant time limits specified in this Section&nbsp;11, the applicant may bring legal action for benefits under the Plan pursuant to Section&nbsp;502(a) of ERISA.
</FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 10. B<SMALL>ASIS</SMALL> O<SMALL>F</SMALL> P<SMALL>AYMENTS</SMALL> T<SMALL>O</SMALL> A<SMALL>ND</SMALL> F<SMALL>ROM</SMALL>
P<SMALL>LAN</SMALL>. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">All benefits under the Plan shall be paid by the Company. The Plan shall be unfunded, and benefits hereunder shall
be paid only from the general assets of the Company. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 11. O<SMALL>THER</SMALL> I<SMALL>NFORMATION</SMALL>. </B></FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(a) Employer and Plan Identification Numbers.</B> The Employer Identification Number assigned to the Company (which is the &#147;Plan Sponsor&#148; as
that term is used in ERISA) by the Internal Revenue Service is 94-3217016. The Plan Number assigned to the Plan by the Plan Sponsor pursuant to the instructions of the Internal Revenue Service is 510. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(b) Ending Date for Plan&#146;s Fiscal Year.</B> The date of the end of the fiscal year for the purpose of maintaining the Plan&#146;s records is
December&nbsp;31. </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">12.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(c) Agent for the Service of Legal Process</B>. The agent for the service of legal process with
respect to the Plan is: </FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="2">Attn: Senior Vice President/General Counsel </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">3832 Bay Center Place </FONT></P> <P
STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">Hayward, CA 94545 </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(d) Plan Sponsor and
Administrator.</B> The &#147;Plan Sponsor&#148; and the &#147;Plan Administrator&#148; of the Plan is: </FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated
</FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">Attn: Senior Vice President/General Counsel </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="2">3832 Bay Center Place </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">Hayward, CA 94545 </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT
FACE="Times New Roman" SIZE="2">The Plan Sponsor&#146;s and Plan Administrator&#146;s telephone number is (510)&nbsp;732-8400. The Plan Administrator is the named fiduciary charged with the responsibility for administering the Plan. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 12. S<SMALL>TATEMENT</SMALL> O<SMALL>F</SMALL> ERISA R<SMALL>IGHTS</SMALL>. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2">Employee is entitled to certain rights and protections under ERISA. For the purposes of this Section&nbsp;14 and, under ERISA, you are entitled to: </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT
FACE="Times New Roman" SIZE="2"><B>Receive Information About Your Plan and Benefits </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(a) </B>Examine, without charge, at the Plan
Administrator&#146;s office and at other specified locations, such as worksites, all documents governing the Plan and a copy of the latest annual report (Form 5500 Series), if applicable, filed by the Plan with the U.S. Department of Labor and
available at the Public Disclosure Room of the Employee Benefits Security Administration; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(b) </B>Obtain, upon written request to the
Plan Administrator, copies of documents governing the operation of the Plan and copies of the latest annual report (Form 5500 Series), if applicable, and an updated (as necessary) Summary Plan Description. The Administrator may make a reasonable
charge for the copies; and </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(c) </B>Receive a summary of the Plan&#146;s annual financial report, if applicable. The Plan Administrator
is required by law to furnish each Employee with a copy of this summary annual report. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>Prudent Actions By Plan Fiduciaries </B></FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">In addition to creating rights for employees covered by the Plan, ERISA imposes duties upon the people who are responsible for the operation of the
employee benefit plan. The people who operate the Plan, called &#147;fiduciaries&#148; of the Plan, have a duty to do so prudently and in the interest of you and other employees and beneficiaries covered by the Plan. No one, including your employer,
your union or any other person, may fire you or otherwise discriminate against you in any way to prevent you from obtaining a Plan benefit or exercising your rights under ERISA. </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT
SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">13.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>Enforce Your Rights </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2">If your claim for a Plan benefit is denied or ignored, in whole or in part, you have a right to know why this was done, to obtain copies of documents relating to the decision without charge, and to appeal any denial,
all within certain time schedules. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">Under ERISA, there are steps you can take to enforce the above rights. For instance, if you request a
copy of Plan documents or the latest annual report from the Plan, if applicable, and do not receive them within 30 days, you may file suit in a Federal court. In such a case, the court may require the Plan Administrator to provide the materials and
pay you up to $110 a day until you receive the materials, unless the materials were not sent because of reasons beyond the control of the Plan Administrator. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2">If you have a claim for benefits which is denied or ignored, in whole or in part, you may file suit in a state or Federal court. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2">If you are discriminated against for asserting your rights, you may seek assistance from the U.S. Department of Labor, or you may file suit in a Federal court. The court will decide who should pay court costs and
legal fees. If you are successful, the court may order the person you have sued to pay these costs and fees. If you lose, the court may order you to pay these costs and fees, for example, if it finds your claim is frivolous. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>Assistance With Your Questions </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">If you have any
questions about the Plan, you should contact the Plan Administrator. If you have any questions about this statement or about your rights under ERISA, or if you need assistance in obtaining documents from the Plan Administrator, you should contact
the nearest office of the Employee Benefits Security Administration, U.S. Department of Labor, listed in your telephone directory or the Division of Technical Assistance and Inquiries, Employee Benefits Security Administration, U.S. Department of
Labor, 200 Constitution Avenue N.W., Washington, D.C. 20210. You may also obtain certain publications about your rights and responsibilities under ERISA by calling the publications hotline of the Employee Benefits Security Administration.
</FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>SECTION 13. G<SMALL>ENERAL</SMALL> P<SMALL>ROVISIONS</SMALL>. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2"><B>(a) Notices. </B>Any notice, demand or request required or permitted to be given by either the Company or Employee pursuant to the terms of this Plan shall be in writing and shall be deemed given when delivered
personally or deposited in the U.S. mail, First Class with postage prepaid, and addressed to the parties, in the case of the Company, at the address set forth in Section&nbsp;11(a) and, in the case of Employee, at the address as set forth in the
Company&#146;s employment file maintained for Employee as previously furnished by Employee or such other address as a party may request by notifying the other in writing. </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT
SIZE="1">&nbsp;</FONT></P>

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<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">14.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Level I </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(b) Transfer and Assignment. </B>The rights and obligations of a Employee under this Plan may not
be transferred or assigned without the prior written consent of the Company. This Plan shall be binding upon any surviving entity resulting from a Change in Control and upon any other person who is a successor by merger, acquisition, consolidation
or otherwise to the business formerly carried on by the Company without regard to whether or not such person or entity actively assumes the obligations hereunder. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2"><B>(c) Waiver. </B>Any Party&#146;s failure to enforce any provision or provisions of this Plan shall not in any way be construed as a waiver of any such provision or provisions, nor prevent any Party from thereafter
enforcing each and every other provision of this Plan. The rights granted the Parties herein are cumulative and shall not constitute a waiver of any Party&#146;s right to assert all other legal remedies available to it under the circumstances.
</FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(d) Severability.</B> Should any provision of this Plan be declared or determined to be invalid, illegal or unenforceable, the
validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>(e) Section
Headings.</B> Section headings in this Plan are included for convenience of reference only and shall not be considered part of this Plan for any other purpose. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman"
SIZE="2"><B>SECTION 14. E<SMALL>XECUTION</SMALL>. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">To record the adoption of this Agreement as set forth herein, Kosan Biosciences
Incorporated has caused its duly authorized officer to execute the same as of the Effective Date. </FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><DIV ALIGN="right">
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<TD VALIGN="top" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2"><B>K<SMALL>OSAN</SMALL> B<SMALL>IOSCIENCES</SMALL> I<SMALL>NCORPORATED</SMALL></B></FONT></TD></TR>
<TR>
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">By:</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000">&nbsp;</P></TD></TR>
<TR>
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Name:</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000">&nbsp;</P></TD></TR>
<TR>
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Title:</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000">&nbsp;</P></TD></TR>
</TABLE></DIV> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD WIDTH="79%"></TD></TR>
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<TD VALIGN="top" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2"><B>A<SMALL>GREED</SMALL> <SMALL>AND</SMALL> A<SMALL>CCEPTED</SMALL>:</B></FONT></TD></TR>
<TR>
<TD HEIGHT="16" COLSPAN="3"></TD></TR>
<TR>
<TD VALIGN="top" COLSPAN="3"> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000">&nbsp;</P></TD></TR>
<TR>
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Employee:</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000">&nbsp;</P></TD></TR>
</TABLE> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="49%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="47%"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">15.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
</TABLE>


<p Style='page-break-before:always'>
<HR  SIZE="3" COLOR="#999999" WIDTH="100%" ALIGN="CENTER">


 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">For Employees Age 40 or Older </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"
ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Individual Termination </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>E<SMALL>XHIBIT</SMALL> A </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px"
ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>RELEASE AGREEMENT </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>I understand and agree completely to the terms set forth
in that certain Change in Control and Severance Benefit Agreement by and between Kosan Biosciences, Inc. and the undersigned (the &#147;Agreement&#148;). </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2">I understand that this Release, together with the Agreement, constitutes the complete, final and exclusive embodiment of the entire agreement between the Company and me with regard to the subject matter hereof. I am
not relying on any promise or representation by the Company that is not expressly stated therein. Certain capitalized terms used in this Release are defined in the Agreement. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">I hereby confirm my obligations under the Company&#146;s proprietary information and inventions agreement. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">Except as otherwise set forth in this Release, I hereby generally and completely release the Company and its parents, subsidiaries, successors,
predecessors, affiliates and assigns, and its and their current and former partners, members, directors, officers, employees, shareholders, agents, attorneys, accountants, insurers, affiliates and assigns, from any and all claims, liabilities and
obligations, both known and unknown, that arise out of or are in any way related to events, acts, conduct, or omissions occurring at any time prior to and including the date I sign this Release. This general release includes, but is not limited to:
(a)&nbsp;all claims arising out of or in any way related to my employment with the Company or the termination of that employment; (b)&nbsp;all claims related to my compensation or benefits, including salary, bonuses, commissions, vacation pay,
expense reimbursements, severance pay, fringe benefits, stock, stock options, or any other ownership interests in the Company; (c)&nbsp;all claims for breach of contract, wrongful termination, and breach of the implied covenant of good faith and
fair dealing; (d)&nbsp;all tort claims, including claims for fraud, defamation, emotional distress, and discharge in violation of public policy; and (e)&nbsp;all federal, state, and local statutory claims, including claims for discrimination,
harassment, retaliation, attorneys&#146; fees, or other claims arising under the federal Civil Rights Act of 1964 (as amended), the federal Americans with Disabilities Act of 1990 (as amended), the federal Age Discrimination in Employment Act (as
amended) (&#147;<B><I>ADEA</I></B>&#148;), the federal Employee Retirement Income Security Act of 1974 (as amended), and the California Fair Employment and Housing Act (as amended); <I>provided, however,</I> that nothing in this paragraph shall be
construed in any way to release the Company from its obligation to indemnify me pursuant to agreement or applicable law. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">I acknowledge
that I am knowingly and voluntarily waiving and releasing any rights I may have under the ADEA, and that the consideration given under the Agreement for the waiver and release in the preceding paragraph hereof is in addition to anything of value to
which I was already entitled. I further acknowledge that I have been advised by this writing, as required by the ADEA, that: (a)&nbsp;my waiver and release do not apply to any rights or claims that may arise after the date I sign this Release;
(b)&nbsp;I should consult with an attorney prior to signing this Release (although I may choose voluntarily not do so); (c)&nbsp;I have twenty-one (21)&nbsp;days to </FONT>
</P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="50%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="47%"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">1.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
</TABLE>


<p Style='page-break-before:always'>
<HR  SIZE="3" COLOR="#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0px;margin-bottom:0px">
<FONT FACE="Times New Roman" SIZE="2">consider this Release (although I may choose voluntarily to sign this Release earlier); (d)&nbsp;I have seven (7)&nbsp;days following the date I sign this
Release to revoke the Release by providing written notice to an officer of the Company; and (e)&nbsp;this Release shall not be effective until the date upon which the revocation period has expired, which shall be the eighth day after I sign this
Release. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">I acknowledge that I have read and understand Section&nbsp;1542 of the California Civil Code which reads as follows: <B>&#147;A
general release does not extend to claims which the creditor does not know or suspect to exist in [his][her] favor at the time of executing the release, which if known by him must have materially affected [his][her] settlement with the
debtor.&#148;</B> I hereby expressly waive and relinquish all rights and benefits under that section and any law of any jurisdiction of similar effect with respect to my release of any claims hereunder. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">I acknowledge that to become effective, I must sign and return this Release to the Company so that it is received not later than twenty-one
(21)&nbsp;days following the date it is provided to me. </FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0">

<TR>
<TD WIDTH="12%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="87%"></TD></TR>
<TR>
<TD VALIGN="top" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2"><B>E<SMALL>MPLOYEE</SMALL></B></FONT></TD></TR>
<TR>
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Name:</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000">&nbsp;</P></TD></TR>
<TR>
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Date:</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000">&nbsp;</P></TD></TR>
</TABLE></DIV> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="50%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="47%"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">2.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
</TABLE>


<p Style='page-break-before:always'>
<HR  SIZE="3" COLOR="#999999" WIDTH="100%" ALIGN="CENTER">


 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">For Employees Age 40 or Older </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"
ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Group Termination </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>E<SMALL>XHIBIT</SMALL> B </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px"
ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>RELEASE AGREEMENT </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"><B>I understand and agree completely to the terms set forth
in that certain Change in Control and Severance Benefit Agreement by and between Kosan Biosciences, Inc. and the undersigned (the &#147;Agreement&#148;). </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2">I understand that this Release, together with the Agreement, constitutes the complete, final and exclusive embodiment of the entire agreement between the Company and me with regard to the subject matter hereof. I am
not relying on any promise or representation by the Company that is not expressly stated therein. Certain capitalized terms used in this Release are defined in the Agreement. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">I hereby confirm my obligations under the Company&#146;s proprietary information and inventions agreement. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">Except as otherwise set forth in this Release, I hereby generally and completely release the Company and its parents, subsidiaries, successors,
predecessors, affiliates and assigns, and its and their current and former partners, members, directors, officers, employees, shareholders, agents, attorneys, accountants, insurers, affiliates and assigns, from any and all claims, liabilities and
obligations, both known and unknown, that arise out of or are in any way related to events, acts, conduct, or omissions occurring at any time prior to and including the date I sign this Release. This general release includes, but is not limited to:
(a)&nbsp;all claims arising out of or in any way related to my employment with the Company or the termination of that employment; (b)&nbsp;all claims related to my compensation or benefits, including salary, bonuses, commissions, vacation pay,
expense reimbursements, severance pay, fringe benefits, stock, stock options, or any other ownership interests in the Company; (c)&nbsp;all claims for breach of contract, wrongful termination, and breach of the implied covenant of good faith and
fair dealing; (d)&nbsp;all tort claims, including claims for fraud, defamation, emotional distress, and discharge in violation of public policy; and (e)&nbsp;all federal, state, and local statutory claims, including claims for discrimination,
harassment, retaliation, attorneys&#146; fees, or other claims arising under the federal Civil Rights Act of 1964 (as amended), the federal Americans with Disabilities Act of 1990 (as amended), the federal Age Discrimination in Employment Act (as
amended) (&#147;<B><I>ADEA</I></B>&#148;), the federal Employee Retirement Income Security Act of 1974 (as amended), and the California Fair Employment and Housing Act (as amended); <I>provided, however,</I> that nothing in this paragraph shall be
construed in any way to release the Company from its obligation to indemnify me pursuant to agreement or applicable law. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">I acknowledge
that I am knowingly and voluntarily waiving and releasing any rights I may have under the ADEA, and that the consideration given under the Agreement for the waiver and release in the preceding paragraph hereof is in addition to anything of value to
which I was already entitled. I further acknowledge that I have been advised by this writing, as required by the ADEA, that: (a)&nbsp;my waiver and release do not apply to any rights or claims that may arise after the date I sign this Release;
(b)&nbsp;I should consult with an attorney prior to signing this Release (although I may choose voluntarily not to do so); (c)&nbsp;I have forty-five (45)&nbsp;days to </FONT>
</P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="50%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="47%"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">1.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
</TABLE>


<p Style='page-break-before:always'>
<HR  SIZE="3" COLOR="#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0px;margin-bottom:0px">
<FONT FACE="Times New Roman" SIZE="2">consider this Release (although I may choose voluntarily to sign this Release earlier); (d)&nbsp;I have seven (7)&nbsp;days following the date I sign this
Release to revoke the Release by providing written notice to an office of the Company; (e)&nbsp;this Release shall not be effective until the date upon which the revocation period has expired, which shall be the eighth day after I sign this Release;
and (f)&nbsp;I have received with this Release a detailed list of the job titles and ages of all employees who were terminated in this group termination and the ages of all employees of the Company in the same job classification or organizational
unit who were not terminated. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">I acknowledge that I have read and understand Section&nbsp;1542 of the California Civil Code which reads as
follows: <B>&#147;A general release does not extend to claims which the creditor does not know or suspect to exist in [his][her] favor at the time of executing the release, which if known by him must have materially affected [his][her] settlement
with the debtor.&#148;</B> I hereby expressly waive and relinquish all rights and benefits under that section and any law of any jurisdiction of similar effect with respect to my release of any claims hereunder. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">I acknowledge that to become effective, I must sign and return this Release to the Company so that it is received not later than forty-five
(45)&nbsp;days following the date it is provided to me. </FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0">

<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="87%"></TD></TR>
<TR>
<TD VALIGN="top" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2"><B>E<SMALL>MPLOYEE</SMALL></B></FONT></TD></TR>
<TR>
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Name:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000">&nbsp;</P></TD></TR>
<TR>
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Date:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000">&nbsp;</P></TD></TR>
</TABLE></DIV> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>

<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="50%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="47%"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Kosan Biosciences Incorporated</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">2.</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
</TABLE>

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