AMYRIS, INC.

2005 STOCK OPTION/STOCK ISSUANCE PLAN

ARTICLE ONE

GENERAL PROVISIONS

I.
PURPOSE OF THE PLAN

This 2005 Stock Option/Stock Issuance Plan is intended to promote the interests
of Amyris, Inc., a Delaware corporation, by providing eligible persons in the
Corporation's employ or service with the opportunity to acquire a proprietary
interest, or otherwise increase their proprietary interest, in the Corporation
as an incentive for them to continue in such employ or service.
Capitalized terms herein shall have the meanings assigned to such terms in the
attached Appendix.
II.
STRUCTURE OF THE PLAN

A.The Plan shall be divided into two (2) separate equity programs:

(i)the Option Grant Program under which eligible persons may, at the discretion
of the Plan Administrator, be granted options to purchase shares of Common
Stock, and

(ii)the Stock Issuance Program under which eligible persons may, at the
discretion of the Plan Administrator, be issued shares of Common Stock directly,
either through the immediate purchase of such shares or as a bonus for services
rendered the Corporation (or any Parent or Subsidiary) or pursuant to restricted
stock units or other share right awards which vest upon the completion of a
designated service period or the attainment of pre-established performance
milestones.
 
B.The provisions of Articles One and Four shall apply to both equity programs
under the Plan and shall accordingly govern the interests of all persons under
the Plan.

III.
ADMINISTRATION OF THE PLAN

A.The Plan shall be administered by the Board. However, any or all
administrative functions otherwise exercisable by the Board may be delegated to
the Committee. Members of the Committee shall serve for such period of time as
the Board may determine and shall be subject to removal by the Board at any
time. The Board may also at any time terminate

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the functions of the Committee and reassume all powers and authority previously
delegated to the Committee.
B.The Plan Administrator shall have full power and authority (subject to the
provisions of the Plan) to establish such rules and regulations as it may deem
appropriate for proper administration of the Plan and to make such
determinations under, and issue such interpretations of, the Plan and any
outstanding options or stock issuances thereunder as it may deem necessary or
advisable. Decisions of the Plan Administrator shall be final and binding on all
parties who have an interest in the Plan or any option grant or stock issuance
thereunder.

IV.
ELIGIBILITY

A.The persons eligible to participate in the Plan are as follows:

(i)Employees,

(ii)non-employee members of the Board or the non-employee members of the board
of directors of any Parent or Subsidiary, and

(iii)consultants and other independent advisors who provide services to the
Corporation (or any Parent or Subsidiary).

B.The Plan Administrator shall have full authority to determine, (i) with
respect to the grants made under the Option Grant Program, which eligible
persons are to receive such grants, the time or times when those grants are to
be made, the number of shares to be covered by each such grant, the status of
the granted option as either an Incentive Option or a Non-Statutory Option, the
time or times when each option is to become exercisable, the vesting schedule
(if any) applicable to the option shares and the maximum term for which the
option is to remain outstanding, and (ii) with respect to stock issuances or
other stock-based awards under the Stock Issuance Program, which eligible
persons are to receive such issuances or awards, the time or times when those
issuances or awards are to be made, the number of shares subject to such
issuance or award to each Participant, the vesting schedule (if any) applicable
to the issued shares and the consideration to be paid by the Participant for
such shares.

C.The Plan Administrator shall have the absolute discretion either to grant
options in accordance with the Option Grant Program or to effect stock issuances
in accordance with the Stock Issuance Program.

V.
STOCK SUBJECT TO THE PLAN

A.The stock issuable under the Plan shall be shares of authorized but unissued
or reacquired Common Stock. The maximum number of shares of Common Stock which
may be issued over the term of the Plan shall not exceed Five Million Nine
Hundred Forty-Two Thousand Seven Hundred (5,942,700) shares.

B.Shares of Common Stock subject to outstanding options shall be available for
subsequent issuance under the Plan to the extent (i) the options expire or
terminate for any

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reason prior to exercise in full or (ii) the options are cancelled in accordance
with the cancellation-regrant provisions of Article Two. Unvested shares issued
under the Plan and subsequently repurchased by the Corporation, at a price per
share not greater than the option exercise or direct issue price paid per share,
pursuant to the Corporation's repurchase rights under the Plan shall be added
back to the number of shares of Common Stock reserved for issuance under the
Plan and shall accordingly be available for reissuance through one or more
subsequent option grants or direct stock issuances under the Plan.

C.Should any change be made to the Common Stock by reason of any stock split,
stock dividend, recapitalization, combination of shares, exchange of shares or
other change affecting the outstanding Common Stock as a class without the
Corporation's receipt of consideration, appropriate adjustments shall be made to
(i) the maximum number and/or class of securities issuable under the Plan and
(ii) the number and/or class of securities and the exercise price per share in
effect under each outstanding option in order to prevent the dilution or
enlargement of benefits thereunder. The adjustments determined by the Plan
Administrator shall be final, binding and conclusive. In no event shall any such
adjustments be made in connection with the conversion of one or more outstanding
shares of the Corporation's preferred stock into shares of Common Stock.

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ARTICLE TWO

OPTION GRANT PROGRAM

I.
OPTION TERMS

Each option shall be evidenced by one or more documents in the form approved by
the Plan Administrator; provided, however, that each such document shall comply
with the terms specified below. Each document evidencing an Incentive Option
shall, in addition, be subject to the provisions of the Plan applicable to such
options.
A.Exercise Price.

1.The exercise price per share shall be fixed by the Plan Administrator in
accordance with the following provisions:

(i)The exercise price per share shall not be less than one hundred percent
(100%) of the Fair Market Value per share of Common Stock on the option grant
date.

(ii)If the person to whom the option is granted is a 10% Stockholder, then the
exercise price per share shall not be less than one hundred ten percent (110%)
of the Fair Market Value per share of Common Stock on the option grant date.

2.The exercise price shall become immediately due upon exercise of the option
and shall, subject to the provisions of Section I of Article Four and the
documents evidencing the option, be payable in cash or check made payable to the
Corporation. Should the Common Stock be registered under Section 12 of the 1934
Act at the time the option is exercised, then the exercise price may also be
paid as follows:

(i)    in shares of Common Stock held for the requisite period necessary to
avoid a charge to the Corporation's earnings for financial reporting purposes
and valued at Fair Market Value on the Exercise Date, or

(ii)    to the extent the option is exercised for vested shares, through a
special sale and remittance procedure pursuant to which the Optionee shall
concurrently provide irrevocable instructions (A) to a brokerage firm
(reasonably satisfactory to the Corporation for purposes of administering such
procedure in compliance with any applicable pre-clearance or pre-notification
requirements) to effect the immediate sale of the purchased shares and remit to
the Corporation, out of the sale proceeds available on the settlement date,
sufficient funds to cover the aggregate exercise price payable for the

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purchased shares plus all applicable income and employment taxes required to be
withheld by the Corporation by reason of such exercise and (B) to the
Corporation to deliver the certificates for the purchased shares directly to
such brokerage firm on the settlement date in order to complete the sale.

Except to the extent such sale and remittance procedure is utilized, payment of
the exercise price for the purchased shares must be made on the Exercise Date.
B.Exercise and Term of Options. Each option shall be exercisable at such time or
times, during such period and for such number of shares as shall be determined
by the Plan Administrator and set forth in the documents evidencing the option
grant. However, no option shall have a term in excess of ten (10) years measured
from the option grant date.

C.Effect of Termination of Service.

1.The following provisions shall govern the exercise of any options held by the
Optionee at the time of cessation of Service or death:

(i)    Should the Optionee cease to remain in Service for any reason other than
death, Disability or Misconduct, then the Optionee shall have a period of three
(3) months following the date of such cessation of Service during which to
exercise each outstanding option held by such Optionee.

(ii)    Should Optionee's Service terminate by reason of Disability, then the
Optionee shall have a period of twelve (12) months following the date of such
cessation of Service during which to exercise each outstanding option held by
such Optionee.

(iii)    If the Optionee dies while holding an outstanding option, then the
personal representative of his or her estate or the person or persons to whom
the option is transferred pursuant to the Optionee's will or the laws of
inheritance or the Optionee's designated beneficiary or beneficiaries of that
option shall have a twelve (12)-month period following the date of the
Optionee's death to exercise such option.

(iv)    Under no circumstances, however, shall any such option be exercisable
after the specified expiration of the option term.

(v)    During the applicable post-Service exercise period, the option may not be
exercised in the aggregate for more than the number of vested shares for which
the option is exercisable on the date of the Optionee's cessation of Service. No
additional shares shall vest under the option following the Optionee's cessation
of Service, except to the extent (if any) specifically authorized by the Plan
Administrator in its sole discretion pursuant to an express

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written agreement with Optionee. Upon the expiration of the applicable exercise
period or (if earlier) upon the expiration of the option term, the option shall
terminate and cease to be outstanding for any vested shares for which the option
has not been exercised.

(vi)    Should Optionee's Service be terminated for Misconduct or should
Optionee otherwise engage in Misconduct while holding one or more outstanding
options under the Plan, then all those options shall terminate immediately and
cease to remain outstanding.

2.The Plan Administrator shall have the discretion, exercisable either at the
time an option is granted or at any time while the option remains outstanding,
to:

(i)    extend the period of time for which the option is to remain exercisable
following Optionee's cessation of Service or death from the limited period
otherwise in effect for that option to such greater period of time as the Plan
Administrator shall deem appropriate, but in no event beyond the expiration of
the option term, and/or

(ii)    permit the option to be exercised, during the applicable post-Service
exercise period, not only with respect to the number of vested shares of Common
Stock for which such option is exercisable at the time of the Optionee's
cessation of Service but also with respect to one or more additional
installments in which the Optionee would have vested under the option had the
Optionee continued in Service.

D.Stockholder Rights. The holder of an option shall have no stockholder rights
with respect to the shares subject to the option until such person shall have
exercised the option, paid the exercise price and become the recordholder of the
purchased shares.

E.Unvested Shares. The Plan Administrator shall have the discretion to grant
options which are exercisable for unvested shares of Common Stock. Should the
Optionee cease Service while holding such unvested shares, the Corporation shall
have the right to repurchase any or all of those unvested shares at a price per
share equal to the lower of (i) the exercise price paid per share or (ii) the
Fair Market Value per share of Common Stock at the time of Optionee's cessation
of Service. The terms upon which such repurchase right shall be exercisable
(including the period and procedure for exercise and the appropriate vesting
schedule for the purchased shares) shall be established by the Plan
Administrator and set forth in the document evidencing such repurchase right.
The Plan Administrator may not impose a vesting schedule upon any option grant
or the shares of Common Stock subject to that option which is more restrictive
than twenty percent (20%) vesting per year of Service, with the initial vesting
to occur not later than one (1) year after the option grant date. However, such
limitation shall not be applicable to any option grants made to individuals who
are officers of the Corporation, non-employee Board members or independent
consultants.

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F.First Refusal Rights. Until such time as the Common Stock is first registered
under Section 12 of the 1934 Act, the Corporation shall have the right of first
refusal with respect to any proposed disposition by the Optionee (or any
successor in interest) of any shares of Common Stock issued under the Plan. Such
right of first refusal shall be exercisable in accordance with the terms
established by the Plan Administrator and set forth in the document evidencing
such right.

G.Limited Transferability of Options. An Incentive Stock Option shall be
exercisable only by the Optionee during his or her lifetime and shall not be
assignable or transferable other than by will or by the laws of inheritance
following the Optionee's death. A Non-Statutory Option may be assigned in whole
or in part during the Optionee's lifetime to one or more members of the
Optionee's family or to a trust established exclusively for the Optionee and/or
one or more such family members or to Optionee's former spouse, to the extent
such assignment is in connection with the Optionee's estate plan or pursuant to
a domestic relations order, or to any other person or persons with respect to
whom the Corporation may rely on a registration statement on Form S-8 filed with
the U.S. Securities and Exchange Commission for the exercise of such
Non-Statutory Option in accordance with the General Instructions to Form S-8.
The assigned portion may only be exercised by the person or persons who acquire
a proprietary interest in the Non-Statutory Option pursuant to the assignment.
The terms applicable to the assigned portion shall be the same as those in
effect for the option immediately prior to such assignment and shall be set
forth in such documents issued to the assignee as the Plan Administrator may
deem appropriate. Notwithstanding the foregoing, the Optionee may also designate
one or more persons as the beneficiary or beneficiaries of his or her
outstanding options under the Plan, and those options shall, in accordance with
such designation, automatically be transferred to such beneficiary or
beneficiaries upon the Optionee's death while holding those options. Such
beneficiary or beneficiaries shall take the transferred options subject to all
the terms and conditions of the applicable agreement evidencing each such
transferred option, including (without limitation) the limited time period
during which the option may be exercised following the Optionee's death.

II.
INCENTIVE OPTIONS

The terms specified below shall be applicable to all Incentive Options. Except
as modified by the provisions of this Section II, all the provisions of Articles
One, Two and Four shall be applicable to Incentive Options. Options which are
specifically designated as Non-Statutory Options shall not be subject to the
terms of this Section II.
A.Eligibility. Incentive Options may only be granted to Employees.

B.Dollar Limitation. The aggregate Fair Market Value of the shares of Common
Stock (determined as of the respective date or dates of grant) for which one or
more options granted to any Employee under the Plan (or any other option plan of
the Corporation or any Parent or Subsidiary) may for the first time become
exercisable as Incentive Options during any one (1) calendar year shall not
exceed the sum of One Hundred Thousand Dollars ($100,000). To the extent the
Employee holds two (2) or more such options which become exercisable for the
first time in the same calendar year, the foregoing limitation on the

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exercisability of such options as Incentive Options shall be applied on the
basis of the order in which such options are granted, except to the extent
otherwise provided under applicable law or regulation.

C.    10% Stockholder. If any Employee to whom an Incentive Option is granted is
a 10% Stockholder, then the option term shall not exceed five (5) years measured
from the option grant date.

III.
CHANGE IN CONTROL

A.The shares subject to each option outstanding under the Plan at the time of a
Change in Control shall automatically vest in full so that each such option
shall, immediately prior to the effective date of the Change in Control, become
exercisable for all of the shares of Common Stock at the time subject to that
option and may be exercised for any or all of those shares as fully-vested
shares of Common Stock. However, the shares subject to an outstanding option
shall not vest on such an accelerated basis if and to the extent: (i) such
option is assumed by the successor corporation (or parent thereof) or otherwise
continued in full force and effect pursuant to the terms of the Change in
Control transaction and any repurchase rights of the Corporation with respect to
the unvested option shares are concurrently assigned to such successor
corporation (or parent thereof) or otherwise continued in effect or (ii) such
option is to be replaced with a cash incentive program of the Corporation or any
successor corporation which preserves the spread existing on the unvested option
shares at the time of the Change in Control (the excess of the Fair Market Value
of those shares over the aggregate exercise price payable for such shares) and
provides for subsequent payout of that spread in accordance with the same
vesting schedule applicable to those unvested option shares or (iii) the
acceleration of such option is subject to other limitations imposed by the Plan
Administrator at the time of the option grant.

B.All outstanding repurchase rights shall also terminate automatically, and the
shares of Common Stock subject to those terminated rights shall immediately vest
in full, in the event of any Change in Control, except to the extent: (i) those
repurchase rights are assigned to the successor corporation (or parent thereof)
or otherwise continued in full force and effect pursuant to the terms of the
Change in Control transaction or (ii) such accelerated vesting is precluded by
other limitations imposed by the Plan Administrator at the time the repurchase
right is issued.

C.Immediately following the consummation of the Change in Control, all
outstanding options shall terminate and cease to be outstanding, except to the
extent assumed by the successor corporation (or parent thereof) or otherwise
continued in effect pursuant to the terms of the Change in Control transaction.

D.Each option which is assumed in connection with a Change in Control or
otherwise continued in effect shall be appropriately adjusted, immediately after
such Change in Control, to apply to the number and class of securities which
would have been issuable to the Optionee in consummation of such Change in
Control, had the option been exercised immediately prior to such Change in
Control. Appropriate adjustments shall also be made to (i)

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the number and class of securities available for issuance under the Plan
following the consummation of such Change in Control and (ii) the exercise price
payable per share under each outstanding option, provided the aggregate exercise
price payable for such securities shall remain the same. To the extent the
actual holders of the Corporation's outstanding Common Stock receive cash
consideration for their Common Stock in consummation of the Change in Control,
the successor corporation may, in connection with the assumption or continuation
of the outstanding options under this Plan, substitute one or more shares of its
own common stock with a fair market value equivalent to the cash consideration
paid per share of Common Stock in such Change in Control.

E.The Plan Administrator shall have the discretion, exercisable either at the
time the option is granted or at any time while the option remains outstanding,
to structure one or more options so that those options shall automatically
accelerate and vest in full (and any repurchase rights of the Corporation with
respect to the unvested shares subject to those options shall immediately
terminate) upon the occurrence of a Change in Control, whether or not those
options are to be assumed in the Change in Control or otherwise continued in
effect.

F.The Plan Administrator shall also have full power and authority, exercisable
either at the time the option is granted or at any time while the option remains
outstanding, to structure such option so that the shares subject to that option
will automatically vest on an accelerated basis should the Optionee's Service
terminate by reason of an Involuntary Termination within a designated period
(not to exceed eighteen (18) months) following the effective date of any Change
in Control in which the option is assumed or otherwise continued in effect and
the repurchase rights applicable to those shares do not otherwise terminate. Any
option so accelerated shall remain exercisable for the fully-vested option
shares until the expiration or sooner termination of the option term. In
addition, the Plan Administrator may provide that one or more of the
Corporation's outstanding repurchase rights with respect to shares held by the
Optionee at the time of such Involuntary Termination shall immediately terminate
on an accelerated basis, and the shares subject to those terminated rights shall
accordingly vest at that time.

G.The portion of any Incentive Option accelerated in connection with a Change in
Control shall remain exercisable as an Incentive Option only to the extent the
applicable One Hundred Thousand Dollar ($100,000) limitation is not exceeded. To
the extent such dollar limitation is exceeded, the accelerated portion of such
option shall be exercisable as a Non-Statutory Option under the Federal tax
laws.

H.The grant of options under the Plan shall in no way affect the right of the
Corporation to adjust, reclassify, reorganize or otherwise change its capital or
business structure or to merge, consolidate, dissolve, liquidate or sell or
transfer all or any part of its business or assets.

IV.
CANCELLATION AND REGRANT OF OPTIONS

The Plan Administrator shall have the authority to effect, at any time and from
time to time, with the consent of the affected option holders, the cancellation
of any or all

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outstanding options under the Plan and to grant in substitution therefor new
options covering the same or different number of shares of Common Stock but with
an exercise price per share based on the Fair Market Value per share of Common
Stock on the new option grant date.

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ARTICLE THREE

STOCK ISSUANCE PROGRAM

I.
STOCK ISSUANCE TERMS

Shares of Common Stock may be issued under the Stock Issuance Program through
direct and immediate issuances without any intervening option grants. Each such
stock issuance shall be evidenced by a Stock Issuance Agreement which complies
with the terms specified below. Shares of Common Stock may also be issued under
the Stock Issuance Program pursuant to share right awards or restricted stock
units which entitle the recipients to receive the shares underlying those awards
or units upon the attainment of designated performance goals or the satisfaction
of specified Service requirements or upon the expiration of a designated time
period following the vesting of those awards or units.
A.
Issue Price.

1.The issue price per share shall be fixed by the Plan Administrator but shall
not be less than one hundred percent (100%) of the Fair Market Value per share
of Common Stock on the issue date.

2.Subject to the provisions of Section I of Article Four, shares of Common Stock
may be issued under the Stock Issuance Program for any of the following items of
consideration which the Plan Administrator may deem appropriate in each
individual instance:

(i)    cash or check made payable to the Corporation,

(ii)    past services rendered to the Corporation (or any Parent or Subsidiary),
or

(iii)    any other valid consideration under the California Corporations Code.

B.
Vesting Provisions.

1.Shares of Common Stock issued under the Stock Issuance Program may, in the
discretion of the Plan Administrator, be fully and immediately vested upon
issuance or may vest in one or more installments over the Participant's period
of Service or upon attainment of specified performance objectives. Shares of
Common Stock may also be issued under the Stock Issuance Program pursuant to
share right awards or restricted stock units which entitle the recipients to
receive the shares underlying those awards or units upon the attainment of
designated performance goals or the satisfaction of specified Service
requirements or upon the expiration of a designated time period following the
vesting of those awards or units, including (without limitation) a deferred
distribution date following the termination of the Participant's Service.
However, the Plan Administrator may not impose a vesting schedule upon any stock
issuance or other stock-based award made under the Stock Issuance Program which
is more

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restrictive than twenty percent (20%) vesting per year of Service, with initial
vesting to occur not later than the completion of one (1) year of Service
measured from the date of such issuance or award. Such limitation shall not
apply to any Common Stock issuances made to the officers of the Corporation,
non-employee Board members or independent consultants.

2.Any new, substituted or additional securities or other property (including
money paid other than as a regular cash dividend) which the Participant may have
the right to receive with respect to the Participant's unvested shares of Common
Stock by reason of any stock dividend, stock split, recapitalization,
combination of shares, exchange of shares or other change affecting the
outstanding Common Stock as a class without the Corporation's receipt of
consideration shall be issued subject to (i) the same vesting requirements
applicable to the Participant's unvested shares of Common Stock and (ii) such
escrow arrangements as the Plan Administrator shall deem appropriate.

3.The Participant shall have full stockholder rights with respect to any shares
of Common Stock issued to the Participant under the Stock Issuance Program,
whether or not the Participant's interest in those shares is vested.
Accordingly, the Participant shall have the right to vote such shares and to
receive any regular cash dividends paid on such shares. However,
dividend-equivalent units may be paid or credited, either in cash or in actual
or phantom shares of Common Stock, on outstanding restricted stock unit or share
right awards, subject to such terms and conditions as the Plan Administrator may
deem appropriate.

4.Should the Participant cease to remain in Service while holding one or more
unvested shares of Common Stock issued under the Stock Issuance Program or
should the performance objectives not be attained with respect to one or more
such unvested shares of Common Stock, then those shares shall be immediately
surrendered to the Corporation for cancellation, and the Participant shall have
no further stockholder rights with respect to those shares. To the extent the
surrendered shares were previously issued to the Participant for consideration
paid in cash or cash equivalent (including the Participant's purchase-money
indebtedness), the Corporation shall repay to the Participant the lower of (i)
the cash consideration paid for the surrendered shares or (ii) the Fair Market
Value of those shares at the time of Participant's cessation of Service and
shall cancel the unpaid principal balance of any outstanding purchase-money note
of the Participant attributable to such surrendered shares by the applicable
clause (i) or (ii) amount.

5.The Plan Administrator may in its discretion waive the surrender and
cancellation of one or more unvested shares of Common Stock (or other assets
attributable thereto) which would otherwise occur upon the non-completion of the
vesting schedule applicable to those shares. Such waiver shall result in the
immediate vesting of the Participant's interest in the shares of Common Stock as
to which the waiver applies. Such waiver may be effected at any time, whether
before or after the Participant's cessation of Service or the attainment or
non-attainment of the applicable performance objectives.

6.Outstanding share right awards or restricted stock units under the Stock
Issuance Program shall automatically terminate, and no shares of Common Stock
shall actually be issued in satisfaction of those awards or units, if the
performance goals or Service

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requirements established for such awards or units are not attained or satisfied.
The Plan Administrator, however, shall have the discretionary authority to issue
vested shares of Common Stock under one or more outstanding share right awards
or restricted stock units as to which the designated performance goals or
Service requirements have not been attained or satisfied.

C.First Refusal Rights. Until such time as the Common Stock is first registered
under Section 12 of the 1934 Act, the Corporation shall have the right of first
refusal with respect to any proposed disposition by the Participant (or any
successor in interest) of any shares of Common Stock issued under the Stock
Issuance Program. Such right of first refusal shall be exercisable in accordance
with the terms established by the Plan Administrator and set forth in the
document evidencing such right.

II.
CHANGE IN CONTROL

A.Upon the occurrence of a Change in Control, all outstanding repurchase rights
under the Stock Issuance Program shall terminate automatically, and the shares
of Common Stock subject to those terminated rights shall immediately vest in
full, except to the extent: (i) those repurchase rights are assigned to the
successor corporation (or parent thereof) or otherwise continued in full force
and effect pursuant to the terms of the Change in Control transaction or (ii)
such accelerated vesting is precluded by other limitations imposed by the Plan
Administrator at the time the repurchase right is issued.

B.Each outstanding restricted stock unit or share right award assumed in
connection with a Change in Control or otherwise continued in effect shall be
adjusted immediately after the consummation of that Change in Control so as to
apply to the number and class of securities into which the shares of Common
Stock subject to the award immediately prior to the Change in Control would have
been converted in consummation of such Change in Control had those shares
actually been outstanding at that time. To the extent the actual holders of the
Corporation's outstanding Common Stock receive cash consideration for their
Common Stock in consummation of the Change in Control, the successor corporation
may, in connection with the assumption or continuation of the outstanding
restricted stock units or share right awards, substitute one or more shares of
its own common stock with a fair market value equivalent to the cash
consideration paid per share of Common Stock in such Change in Control
transaction. If any such restricted stock unit or share right award is not so
assumed or otherwise continued in effect, or if such unit or award is not
replaced with a cash incentive award which preserves the Fair Market Value of
the Common Stock underlying that unit or award at the time of the Change in
Control and provides for subsequent payout of the dollar amount in accordance
with the vesting schedule in effect for such unit or award at the time of the
Change in Control, then such unit or award shall vest, and the shares of Common
Stock subject to such unit or award shall become issuable immediately prior to
the consummation of the Change in Control.

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C.The Plan Administrator shall have the discretionary authority to structure one
or more unvested stock issuances or one or more restricted stock unit or other
share right awards under the Stock Issuance Program so that the shares of Common
Stock subject to those issuances or awards shall automatically vest (or vest and
become issuable) in whole or in part immediately upon the occurrence of a Change
in Control or upon the subsequent termination of the Participant's Service by
reason of an Involuntary Termination within a designated period (not to exceed
eighteen (18) months) following the effective date of that Change in Control
transaction.

III.
SHARE ESCROW/LEGENDS

Unvested shares may, in the Plan Administrator's discretion, be held in escrow
by the Corporation until the Participant's interest in such shares vests or may
be issued directly to the Participant with restrictive legends on the
certificates evidencing those unvested shares.

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ARTICLE FOUR

MISCELLANEOUS

I.
FINANCING

The Plan Administrator may permit any Optionee or Participant to pay the option
exercise price under the Option Grant Program or the purchase price for shares
issued under the Stock Issuance Program by delivering a full-recourse promissory
note payable in one or more installments which bears interest at a market rate
and is secured by the purchased shares. In no event, however, may the maximum
credit available to the Optionee or Participant exceed the sum of (i) the
aggregate option exercise price or purchase price payable for the purchased
shares plus (ii) any applicable income and employment tax liability incurred by
the Optionee or the Participant in connection with the option exercise or share
purchase.
II.
EFFECTIVE DATE AND TERM OF PLAN

A.The Plan shall become effective when adopted by the Board, but no option
granted under the Plan may be exercised, and no shares shall be issued under the
Plan, until the Plan is approved by the Corporation's stockholders. If such
stockholder approval is not obtained within twelve (12) months after the date of
the Board's adoption of the Plan, then all options previously granted under the
Plan shall terminate and cease to be outstanding, and no further options shall
be granted and no shares shall be issued under the Plan. Subject to such
limitation, the Plan Administrator may grant options and issue shares under the
Plan at any time after the effective date of the Plan and before the date fixed
herein for termination of the Plan.

B.The Plan shall terminate upon the earliest of (i) the expiration of the ten
(10)-year period measured from the date the Plan is adopted by the Board, (ii)
the date on which all shares available for issuance under the Plan shall have
been issued as vested shares or (iii) the termination of all outstanding options
in connection with a Change in Control. All options and unvested stock issuances
outstanding at the time of a clause (i) termination event shall continue to have
full force and effect in accordance with the provisions of the documents
evidencing those options or issuances.

III.
AMENDMENT OF THE PLAN

A.The Board shall have complete and exclusive power and authority to amend or
modify the Plan in any or all respects. However, no such amendment or
modification shall adversely affect the rights and obligations with respect to
options or unvested stock issuances at the time outstanding under the Plan
unless the Optionee or the Participant consents to such amendment or
modification. In addition, certain amendments may require stockholder approval
pursuant to applicable laws and regulations.

B.Options may be granted under the Option Grant Program and shares may be issued
under the Stock Issuance Program which are in each instance in excess of the
number

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of shares of Common Stock then available for issuance under the Plan, provided
any excess shares actually issued under those programs shall be held in escrow
until there is obtained stockholder approval of an amendment sufficiently
increasing the number of shares of Common Stock available for issuance under the
Plan. If such stockholder approval is not obtained within twelve (12) months
after the date the first such excess grants or issuances are made, then (i) any
unexercised options granted on the basis of such excess shares shall terminate
and cease to be outstanding and (ii) the Corporation shall promptly refund to
the Optionees and the Participants the exercise or purchase price paid for any
excess shares issued under the Plan and held in escrow, together with interest
(at the applicable Short Term Federal Rate) for the period the shares were held
in escrow, and such shares shall thereupon be automatically cancelled and cease
to be outstanding.

IV.
USE OF PROCEEDS

Any cash proceeds received by the Corporation from the sale of shares of Common
Stock under the Plan shall be used for general corporate purposes.
V.
WITHHOLDING

The Corporation's obligation to deliver shares of Common Stock upon the exercise
of any options granted under the Plan or upon the issuance or vesting of any
shares issued under the Plan shall be subject to the satisfaction of all
applicable income and employment tax withholding requirements.
VI.
REGULATORY APPROVALS

The implementation of the Plan, the granting of any options under the Plan and
the issuance of any shares of Common Stock (i) upon the exercise of any option
or (ii) under the Stock Issuance Program shall be subject to the Corporation's
procurement of all approvals and permits required by regulatory authorities
having jurisdiction over the Plan, the options granted under it and the shares
of Common Stock issued pursuant to it.
VII.
NO EMPLOYMENT OR SERVICE RIGHTS

Nothing in the Plan shall confer upon the Optionee or the Participant any right
to continue in Service for any period of specific duration or interfere with or
otherwise restrict in any way the rights of the Corporation (or any Parent or
Subsidiary employing or retaining such person) or of the Optionee or the
Participant, which rights are hereby expressly reserved by each, to terminate
such person's Service at any time for any reason, with or without cause.

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VIII.
FINANCIAL REPORTS

The Corporation shall deliver a balance sheet and an income statement at least
annually to each individual holding an outstanding option under the Plan, unless
such individual is a key Employee whose duties in connection with the
Corporation (or any Parent or Subsidiary) assure such individual access to
equivalent information.

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APPENDIX
The following definitions shall be in effect under the Plan:
A.Board shall mean the Corporation's Board of Directors.

B.Change in Control shall mean a change in ownership or control of the
Corporation effected through any of the following transactions:

(i)a merger, consolidation or other reorganization approved by the Corporation's
stockholders, unless securities representing more than fifty percent (50%) of
the total combined voting power of the voting securities of the successor
corporation are immediately thereafter beneficially owned, directly or
indirectly and in substantially the same proportion, by the persons who
beneficially owned the Corporation's outstanding voting securities immediately
prior to such transaction, or

(ii)a stockholder-approved sale, transfer or other disposition of all or
substantially all of the Corporation's assets in liquidation or dissolution of
the Corporation, or

(iii)the acquisition, directly or indirectly by any person or related group of
persons (other than the Corporation or a person that directly or indirectly
controls, is controlled by, or is under common control with, the Corporation),
of beneficial ownership (within the meaning of Rule 13d-3 of the 1934 Act) of
securities possessing more than fifty percent (50%) of the total combined voting
power of the Corporation's outstanding securities pursuant to a tender or
exchange offer made directly to the Corporation's stockholders.

In no event shall any public offering of the Corporation's securities be deemed
to constitute a Change in Control.
C.Code shall mean the Internal Revenue Code of 1986, as amended.

D.Committee shall mean a committee of one (1) or more Board members appointed by
the Board to exercise one or more administrative functions under the Plan.
E.Common Stock shall mean the Corporation's common stock.

F.Corporation shall mean Amyris, Inc., a Delaware corporation, and any successor
corporation to all or substantially all of the assets or voting stock of Amyris,
Inc. which shall by appropriate action adopt the Plan.

G.Disability shall mean the inability of the Optionee or the Participant to
engage in any substantial gainful activity by reason of any medically

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determinable physical or mental impairment and shall be determined by the Plan
Administrator on the basis of such medical evidence as the Plan Administrator
deems warranted under the circumstances.

H.Employee shall mean an individual who is in the employ of the Corporation (or
any Parent or Subsidiary), subject to the control and direction of the employer
entity as to both the work to be performed and the manner and method of
performance.

I.Exercise Date shall mean the date on which the Corporation shall have received
written notice of the option exercise.

J.Fair Market Value per share of Common Stock on any relevant date shall be
determined in accordance with the following provisions:

(i)If the Common Stock is at the time traded on the Nasdaq National Market, then
the Fair Market Value shall be the closing selling price per share of Common
Stock on the date in question, as such price is reported by the National
Association of Securities Dealers on the Nasdaq National Market and published in
The Wall Street Journal. If there is no closing selling price for the Common
Stock on the date in question, then the Fair Market Value shall be the closing
selling price on the last preceding date for which such quotation exists.

(ii)If the Common Stock is at the time listed on any Stock Exchange, then the
Fair Market Value shall be the closing selling price per share of Common Stock
on the date in question on the Stock Exchange determined by the Plan
Administrator to be the primary market for the Common Stock, as such price is
officially quoted in the composite tape of transactions on such exchange and
published in The Wall Street Journal. If there is no closing selling price for
the Common Stock on the date in question, then the Fair Market Value shall be
the closing selling price on the last preceding date for which such quotation
exists.

(iii)If the Common Stock is at the time neither listed on any Stock Exchange nor
traded on the Nasdaq National Market, then the Fair Market Value shall be
determined by the Plan Administrator after taking into account such factors as
the Plan Administrator shall deem appropriate.

K.Incentive Option shall mean an option which satisfies the requirements of Code
Section 422.

L.Involuntary Termination shall mean the termination of the Service of any
individual which occurs by reason of:

(i)such individual's involuntary dismissal or discharge by the Corporation for
reasons other than Misconduct, or

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(ii)such individual's voluntary resignation following (A) a change in his or her
position with the Corporation which materially reduces his or her duties and
responsibilities or the level of management to which he or she reports, (B) a
reduction in his or her level of compensation (including base salary, fringe
benefits and target bonus under any corporate-performance based bonus or
incentive programs) by more than fifteen percent (15%) or (C) a relocation of
such individual's place of employment by more than fifty (50) miles, provided
and only if such change, reduction or relocation is effected without the
individual's consent.
 
M.Misconduct shall mean the commission of any act of fraud, embezzlement or
dishonesty by the Optionee or Participant, any unauthorized use or disclosure by
such person of confidential information or trade secrets of the Corporation (or
any Parent or Subsidiary), or any other intentional misconduct by such person
adversely affecting the business or affairs of the Corporation (or any Parent or
Subsidiary) in a material manner. The foregoing definition shall not in any way
preclude or restrict the right of the Corporation (or any Parent or Subsidiary)
to discharge or dismiss any Optionee, Participant or other person in the Service
of the Corporation (or any Parent or Subsidiary) for any other acts or
omissions, but such other acts or omissions shall not be deemed, for purposes of
the Plan, to constitute grounds for termination for Misconduct.

N.1934 Act shall mean the Securities Exchange Act of 1934, as amended.

O.Non-Statutory Option shall mean an option not intended to satisfy the
requirements of Code Section 422.

P.Option Grant Program shall mean the option grant program in effect under the
Plan.

Q.Optionee shall mean any person to whom an option is granted under the Plan.

R.Parent shall mean any corporation (other than the Corporation) in an unbroken
chain of corporations ending with the Corporation, provided each corporation in
the unbroken chain (other than the Corporation) owns, at the time of the
determination, stock possessing fifty percent (50%) or more of the total
combined voting power of all classes of stock in one of the other corporations
in such chain.

S.Participant shall mean any person who is issued shares of Common Stock under
the Stock Issuance Program.

T.Plan shall mean the Corporation's 2005 Stock Option/Stock Issuance Plan, as
set forth in this document.

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U.Plan Administrator shall mean either the Board or the Committee acting in its
capacity as administrator of the Plan.

V.Service shall mean the performance of services for the Corporation (or any
Parent or Subsidiary, whether now existing or subsequently established) by a
person in the capacity of an Employee, a non-employee member of the board of
directors or a consultant or independent advisor, except to the extent otherwise
specifically provided in the documents evidencing the option grant or stock
issuance. For purposes of the Plan, an Optionee or Participant shall be deemed
to cease Service immediately upon the occurrence of the either of the following
events: (i) Optionee or Participant no longer performs services in any of the
foregoing capacities for the Corporation or any Parent or Subsidiary or (ii) the
entity for which Optionee or Participant is performing such services ceases to
remain a Parent or Subsidiary of the Corporation, even though the Optionee or
Participant may subsequently continue to perform services for that entity.
Service shall not be deemed to cease during a period of military leave, sick
leave or other personal leave approved by the Corporation; provided, however,
that for a leave which exceeds three (3) months, Service shall be deemed, for
purposes of determining the period within which any outstanding option held by
the Optionee in question may be exercised as an Incentive Option, to cease on
the first day immediately following the expiration of such three (3)-month
period, unless that Optionee is provided with the right to return to Service
following such leave either by statute or by written contract. Except to the
extent otherwise required by law or expressly authorized by the Plan
Administrator, no Service credit shall be given for vesting purposes for any
period the Optionee or Participant is on a leave of absence.

W.Stock Exchange shall mean either the American Stock Exchange or the New York
Stock Exchange.

X.Stock Issuance Agreement shall mean the agreement entered into by the
Corporation and the Participant at the time of issuance of shares of Common
Stock under the Stock Issuance Program.

Y.Stock Issuance Program shall mean the stock issuance program in effect under
the Plan.

Z.Subsidiary shall mean any corporation (other than the Corporation) in an
unbroken chain of corporations beginning with the Corporation, provided each
corporation (other than the last corporation) in the unbroken chain owns, at the
time of the determination, stock possessing fifty percent (50%) or more of the
total combined voting power of all classes of stock in one of the other
corporations in such chain.

AA.10% Stockholder shall mean the owner of stock (as determined under Code
Section 424(d)) possessing more than ten percent (10%) of the total combined
voting power of all classes of stock of the Corporation (or any Parent or
Subsidiary).

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