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                                                                    EXHIBIT 10.3

                         LARGE SCALE BIOLOGY CORPORATION

                          EMPLOYEE STOCK PURCHASE PLAN


        I. PURPOSE OF THE PLAN

             This Employee Stock Purchase Plan is intended to promote the
interests of Large Scale Biology Corporation, a California corporation, by
providing eligible employees with the opportunity to acquire a proprietary
interest in the Corporation through participation in a payroll deduction-based
employee stock purchase plan designed to qualify under Section 423 of the Code.

             Capitalized terms herein shall have the meanings assigned to such
terms in the attached Appendix.

        II. ADMINISTRATION OF THE PLAN

             The Plan Administrator shall have full authority to interpret and
construe any provision of the Plan and to adopt such rules and regulations for
administering the Plan as it may deem necessary in order to comply with the
requirements of Code Section 423. Decisions of the Plan Administrator shall be
final and binding on all parties having an interest in the Plan.

        III. STOCK SUBJECT TO PLAN

             A. The stock purchasable under the Plan shall be shares of
authorized but unissued or reacquired Common Stock, including shares of Common
Stock purchased on the open market. The number of shares of Common Stock
initially reserved for issuance over the term of the Plan shall be limited to
350,000 shares.

             B. The number of shares of Common Stock available for issuance
under the Plan shall automatically increase on the first trading day of January
each calendar year during the term of the Plan, beginning with calendar year
2001, by (i) an amount equal to one percent (1%) of the total number of shares
of Common Stock outstanding on the last trading day in December of the
immediately preceding calendar year, but in no event shall any such annual
increase exceed 350,000 shares, or (ii) such lesser amount as determined by the
Plan Administrator.

             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 class of securities issuable under
the Plan, (ii) the maximum number and class of securities purchasable per
Participant on any one Purchase Date, (iii) the maximum number and class of
securities purchasable in total by all Participants on any one Purchase Date,
(iv) the maximum number


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and/or class of securities by which the share reserve is to increase
automatically each calendar year pursuant to the provisions of Section III.B of
this Article One and (v) the number and class of securities and the price per
share in effect under each outstanding purchase right in order to prevent the
dilution or enlargement of benefits thereunder.

        IV. OFFERING PERIODS

             A. Shares of Common Stock shall be offered for purchase under the
Plan through a series of overlapping offering periods until such time as (i) the
maximum number of shares of Common Stock available for issuance under the Plan
shall have been purchased or (ii) the Plan shall have been sooner terminated.

             B. Each offering period shall be of such duration (not to exceed
twenty-four (24) months) as determined by the Plan Administrator prior to the
start date of such offering period. Offering periods shall commence at
semi-annual intervals on the first business day of February and August each year
over the term of the Plan. Accordingly, two (2) separate offering periods shall
commence in each calendar year the Plan remains in existence. However, the
initial offering period shall commence at the Effective Time and terminate on
the last business day in July 2002 .

             C. Each offering period shall consist of a series of one or more
successive Purchase Intervals. Purchase Intervals shall run from the first
business day in February to the last business day in July each year and from the
first business day in August each year to the last business day in January in
the following year. However, the first Purchase Interval in effect under the
initial offering period shall commence at the Effective Time and terminate on
the last business day in January 2001.

        V. ELIGIBILITY

             A. Each individual who is an Eligible Employee on the start date of
any offering period under the Plan may enter that offering period on such start
date. However, an Eligible Employees may participate in only one offering period
at a time.



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             B. an Eligible Employee must, in order to participate in a
particular offering period, complete the enrollment forms prescribed by the Plan
Administrator (including a stock purchase agreement and a payroll deduction
authorization) and file such forms with the Plan Administrator (or its
designate) on or before the start date of that offering period.

        VI. PAYROLL DEDUCTIONS

             A. The payroll deduction authorized by the Participant for purposes
of acquiring shares of Common Stock during an offering period may be any
multiple of one percent (1%) of the Base salary paid to the Participant during
each Purchase Interval within that offering period, up to a maximum of fifteen
percent (15%). The deduction rate so authorized shall continue in effect
throughout the offering period, except to the extent such rate is changed in
accordance with the following guidelines:

                    (i) The Participant may, at any time during the offering
        period, reduce his or her rate of payroll deduction to become effective
        as soon as possible after filing the appropriate form with the Plan
        Administrator. The Participant may not, however, effect more than one
        (1) such reduction per Purchase Interval.

                    (ii) The Participant may, prior to the commencement of any
        new Purchase Interval within the offering period, increase the rate of
        his or her payroll deduction by filing the appropriate form with the
        Plan Administrator. The new rate (which may not exceed the fifteen
        percent (15%) maximum) shall become effective on the start date of the
        first Purchase Interval following the filing of such form.

             B. Payroll deductions shall begin on the first pay day
administratively feasible following the start date of the offering period and
shall (unless sooner terminated by the Participant) continue through the pay day
ending with or immediately prior to the last day of that offering period. The
amounts so collected shall be credited to the Participant's book account under
the Plan, but no interest shall be paid on the balance from time to time
outstanding in such account. The amounts collected from the Participant shall
not be required to be held in any segregated account or trust fund and may be
commingled with the general assets of the Corporation and used for general
corporate purposes.

             C. Payroll deductions shall automatically cease upon the
termination of the Participant's purchase right in accordance with the
provisions of the Plan.

             D. The Participant's acquisition of Common Stock under the Plan on
any Purchase Date shall neither limit nor require the Participant's acquisition
of Common Stock on any subsequent Purchase Date, whether within the same or a
different offering period.

        VII. PURCHASE RIGHTS

             A. GRANT OF PURCHASE RIGHTS. A Participant shall be granted a
separate purchase right for each offering period in which he or she is enrolled.
The purchase right shall



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be granted on the start date of the offering period and shall provide the
Participant with the right to purchase shares of Common Stock, in a series of
successive installments during that offering period, upon the terms set forth
below. The Participant shall execute a stock purchase agreement embodying such
terms and such other provisions (not inconsistent with the Plan) as the Plan
Administrator may deem advisable.

             Under no circumstances shall purchase rights be granted under the
Plan to any Eligible Employee if such individual would, immediately after the
grant, own (within the meaning of Code Section 424(d)) or hold outstanding
options or other rights to purchase, stock possessing five percent (5%) or more
of the total combined voting power or value of all classes of stock of the
Corporation or any Corporate Affiliate.

             B. EXERCISE OF THE PURCHASE RIGHT. Each purchase right shall be
automatically exercised in installments on each successive Purchase Date within
the offering period, and shares of Common Stock shall accordingly be purchased
on behalf of each Participant on each such Purchase Date. The purchase shall be
effected by applying the Participant's payroll deductions for the Purchase
Interval ending on such Purchase Date to the purchase of whole shares of Common
Stock at the purchase price in effect for the Participant for that Purchase
Date.

             C. PURCHASE PRICE. The purchase price per share at which Common
Stock will be purchased on the Participant's behalf on each Purchase Date within
the particular offering period in which he or she is enrolled shall be equal to
eighty-five percent (85%) of the lower of (i) the Fair Market Value per share of
Common Stock on the start date of that offering period or (ii) the Fair Market
Value per share of Common Stock on that Purchase Date.

             D. NUMBER OF PURCHASABLE SHARES. The number of shares of Common
Stock purchasable by a Participant on each Purchase Date during the particular
offering period in which he or she is enrolled shall be the number of whole
shares obtained by dividing the amount collected from the Participant through
payroll deductions during the Purchase Interval ending with that Purchase Date
by the purchase price in effect for the Participant for that Purchase Date.
However, the maximum number of shares of Common Stock purchasable per
Participant on any one Purchase Date shall not exceed 500 shares, subject to
periodic adjustments in the event of certain changes in the Corporation's
capitalization. However, the Plan Administrator shall have the discretionary
authority, exercisable prior to the start of any offering period under the Plan,
to increase or decrease the limitation to be in effect for the number of shares
purchasable per Participant enrolled in that particular offering period on each
Purchase Date which occurs during that offering period.

             E. EXCESS PAYROLL DEDUCTIONS. Any payroll deductions not applied to
the purchase of shares of Common Stock on any Purchase Date because they are not
sufficient to purchase a whole share of Common Stock shall be held for the
purchase of Common Stock on the next Purchase Date. However, any payroll
deductions not applied to the purchase of Common Stock by reason of the
limitation on the maximum number of shares purchasable per Participant or in
total by all Participants on the Purchase Date shall be promptly refunded.



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             F. TERMINATION OF PURCHASE RIGHT. The following provisions shall
govern the termination of outstanding purchase rights:

                    (i) A Participant may, at any time prior to the next
        scheduled Purchase Date in the offering period in which he or she is
        enrolled, terminate his or her outstanding purchase right by filing the
        appropriate form with the Plan Administrator (or its designate), and no
        further payroll deductions shall be collected from the Participant with
        respect to the terminated purchase right. Any payroll deductions
        collected during the Purchase Interval in which such termination occurs
        shall, at the Participant's election, be immediately refunded or held
        for the purchase of shares on the next Purchase Date. If no such
        election is made at the time such purchase right is terminated, then the
        payroll deductions collected with respect to the terminated right shall
        be refunded as soon as possible.

                    (ii) The termination of such purchase right shall be
        irrevocable, and the Participant may not subsequently rejoin the
        offering period for which the terminated purchase right was granted. In
        order to resume participation in any subsequent offering period, such
        individual must re-enroll in the Plan (by making a timely filing of the
        prescribed enrollment forms) on or before the start date of that
        offering period.

                    (iii) Should the Participant cease to remain an Eligible
        Employee for any reason (including death, disability or change in
        status) while his or her purchase right remains outstanding, then that
        purchase right shall immediately terminate, and all of the Participant's
        payroll deductions for the Purchase Interval in which the purchase right
        so terminates shall be immediately refunded. However, should the
        Participant cease to remain in active service by reason of an approved
        unpaid leave of absence, then the Participant shall have the right,
        exercisable up until the last business day of the Purchase Interval in
        which such leave commences, to (a) withdraw all the payroll deductions
        collected to date on his or her behalf for that Purchase Interval or (b)
        have such funds held for the purchase of shares on his or her behalf on
        the next scheduled Purchase Date. In no event, however, shall any
        further payroll deductions be collected on the Participant's behalf
        during such leave. Upon the Participant's return to active service (x)
        within ninety (90) days following the commencement of such leave or (y)
        prior to the expiration of any longer period for which such
        Participant's right



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        to reemployment with the Corporation is guaranteed by statute or
        contract, his or her payroll deductions under the Plan shall
        automatically resume at the rate in effect at the time the leave began,
        unless the Participant withdraws from the Plan prior to his or her
        return. An individual who returns to active employment following a leave
        of absence that exceeds in duration the applicable (x) or (y) time
        period will be treated as a new Employee for purposes of subsequent
        participation in the Plan and must accordingly re-enroll in the Plan (by
        making a timely filing of the prescribed enrollment forms) on or before
        the start date of any subsequent offering period in which he or she
        wishes to participate.

             G. CHANGE IN CONTROL. Each outstanding purchase right shall
automatically be exercised, immediately prior to the effective date of any
Change in Control, by applying the payroll deductions of each Participant for
the Purchase Interval in which such Change in Control occurs to the purchase of
whole shares of Common Stock at a purchase price per share equal to eighty-five
percent (85%) of the lower of (i) the Fair Market Value per share of Common
Stock on the start date of the offering period in which such individual is
enrolled at the time of such Change in Control or (ii) the Fair Market Value per
share of Common Stock immediately prior to the effective date of such Change in
Control. However, the applicable limitation on the number of shares of Common
Stock purchasable per Participant shall continue to apply to any such purchase,
but not the limitation applicable to the maximum number of shares of Common
Stock purchasable in total by all Participants on any one Purchase Date.

             The Corporation shall use its best efforts to provide at least ten
(10) days' prior written notice of the occurrence of any Change in Control, and
Participants shall, following the receipt of such notice, have the right to
terminate their outstanding purchase rights prior to the effective date of the
Change in Control.

             H. PRORATION OF PURCHASE RIGHTS. Should the total number of shares
of Common Stock to be purchased pursuant to outstanding purchase rights on any
particular date exceed the number of shares then available for issuance under
the Plan, the Plan Administrator shall make a pro-rata allocation of the
available shares on a uniform and nondiscriminatory basis, and the payroll
deductions of each Participant, to the extent in excess of the aggregate
purchase price payable for the Common Stock pro-rated to such individual, shall
be refunded.

             I. ASSIGNABILITY. The purchase right shall be exercisable only by
the Participant and shall not be assignable or transferable by the Participant.

             J. STOCKHOLDER RIGHTS. A Participant shall have no stockholder
rights with respect to the shares subject to his or her outstanding purchase
right until the shares are purchased on the Participant's behalf in accordance
with the provisions of the Plan and the Participant has become a holder of
record of the purchased shares.



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        VIII. ACCRUAL LIMITATIONS

             A. No Participant shall be entitled to accrue rights to acquire
Common Stock pursuant to any purchase right outstanding under this Plan if and
to the extent such accrual, when aggregated with (i) rights to purchase Common
Stock accrued under any other purchase right granted under this Plan and (ii)
similar rights accrued under other employee stock purchase plans (within the
meaning of Code Section 423)) of the Corporation or any Corporate Affiliate,
would otherwise permit such Participant to purchase more than Twenty-Five
Thousand Dollars ($25,000.00) worth of stock of the Corporation or any Corporate
Affiliate (determined on the basis of the Fair Market Value per share on the
date or dates such rights are granted) for each calendar year such rights are at
any time outstanding.

             B. For purposes of applying such accrual limitations to the
purchase rights granted under the Plan, the following provisions shall be in
effect:

                    (i) The right to acquire Common Stock under each outstanding
        purchase right shall accrue in a series of installments on each
        successive Purchase Date during the offering period in which such right
        remains outstanding.

                    (ii) No right to acquire Common Stock under any outstanding
        purchase right shall accrue to the extent the Participant has already
        accrued in the same calendar year the right to acquire Common Stock
        under one or more other purchase rights at a rate equal to Twenty-Five
        Thousand Dollars ($25,000.00) worth of Common Stock (determined on the
        basis of the Fair Market Value per share on the date or dates of grant)
        for each calendar year such rights were at any time outstanding.

             C. If by reason of such accrual limitations, any purchase right of
a Participant does not accrue for a particular Purchase Interval, then the
payroll deductions that the Participant made during that Purchase Interval with
respect to such purchase right shall be promptly refunded.

             D. In the event there is any conflict between the provisions of
this Article and one or more provisions of the Plan or any instrument issued
thereunder, the provisions of this Article shall be controlling.

        IX. EFFECTIVE DATE AND TERM OF THE PLAN

             A. The Plan was adopted by the Board on July ___, 2000, and shall
become effective at the Effective Time, provided no purchase rights granted
under the Plan shall be exercised, and no shares of Common Stock shall be issued
hereunder, until (i) the Plan shall have been approved by the stockholders of
the Corporation and (ii) the Corporation shall have complied with all applicable
requirements of the 1933 Act (including the registration of the shares of Common
Stock issuable under the Plan on a Form S-8 registration statement filed with
the Securities and Exchange Commission), all applicable listing requirements of
any stock



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exchange (or the Nasdaq National Market, if applicable) on which the Common
Stock is listed for trading and all other applicable requirements established by
law or regulation. In the event such stockholder approval is not obtained, or
such compliance is not effected, within twelve (12) months after the date on
which the Plan is adopted by the Board, the Plan shall terminate and have no
further force or effect, and all sums collected from Participants during the
initial offering period hereunder shall be refunded.

             B. Unless sooner terminated by the Board, the Plan shall terminate
upon the earliest of (i) the last business day in July 2010, (ii) the date on
which all shares available for issuance under the Plan shall have been sold
pursuant to purchase rights exercised under the Plan or (iii) the date on which
all purchase rights are exercised in connection with a Change in Control. No
further purchase rights shall be granted or exercised, and no further payroll
deductions shall be collected, under the Plan following such termination.

        X. AMENDMENT OF THE PLAN

             A. The Board may alter, amend, suspend or terminate the Plan at any
time to become effective immediately following the close of any Purchase
Interval. However, the Plan may be amended or terminated immediately upon Board
action, if and to the extent necessary to assure that the Corporation will not
recognize, for financial reporting purposes, any compensation expense in
connection with the shares of Common Stock offered for purchase under the Plan,
should the financial accounting rules applicable to the Plan at the Effective
Time be subsequently revised so as to require the Corporation to recognize
compensation expense in the absence of such amendment or termination.

             B. In no event may the Board effect any of the following amendments
or revisions to the Plan without the approval of the Corporation's stockholders:
(i) increase the number of shares of Common Stock issuable under the Plan,
except for permissible adjustments in the event of certain changes in the
Corporation's capitalization, (ii) alter the purchase price formula so as to
reduce the purchase price payable for the shares of Common Stock purchasable
under the Plan or (iii) modify the eligibility requirements for participation in
the Plan.

        XI. GENERAL PROVISIONS

             A. All costs and expenses incurred in the administration of the
Plan shall be paid by the Corporation; however, each Plan Participant shall bear
all costs and expenses incurred by such individual in the sale or other
disposition of any shares purchased under the Plan.

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



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             C. The provisions of the Plan shall be governed by the laws of the
State of California without resort to that State's conflict-of-laws rules.



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                                   SCHEDULE A

                          CORPORATIONS PARTICIPATING IN
                          EMPLOYEE STOCK PURCHASE PLAN
                            AS OF THE EFFECTIVE TIME

                         Large Scale Biology Corporation


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                                    APPENDIX


             The following definitions shall be in effect under the Plan:

             D. BASE SALARY shall mean the base salary payable to a Participant
by one or more Participating Corporations during such individual's period of
participation in one or more offering periods under the Plan; Base Salary shall
not include any overtime payments, bonuses, commissions, current profit-sharing
distributions or other incentive-type payments. Such Base Salary shall be
calculated before deduction of (A) any income or employment tax withholdings or
(B) any pre-tax contributions made by the Participant to any Code Section 401(k)
salary deferral plan or any Code Section 125 cafeteria benefit program now or
hereafter established by the Corporation or any Corporate Affiliate.

             A. BOARD shall mean the Corporation's Board of Directors.

             B. CHANGE IN CONTROL shall mean a change in ownership of the
Corporation pursuant to any of the following transactions:

                    (i) a merger or consolidation in which securities possessing
        more than fifty percent (50%) of the total combined voting power of the
        Corporation's outstanding securities are transferred to a person or
        persons different from the persons holding those securities immediately
        prior to such transaction, or

                    (ii) the sale, transfer or other disposition of all or
        substantially all of the assets of the Corporation in complete
        liquidation or dissolution of the Corporation, or

                    (iii) the acquisition, directly or indirectly, by a 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.

             C. CODE shall mean the Internal Revenue Code of 1986, as amended.

             D. COMMON STOCK shall mean the Corporation's common stock.

             E. CORPORATE AFFILIATE shall mean any parent or subsidiary
corporation of the Corporation (as determined in accordance with Code Section
424), whether now existing or subsequently established.


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             F. CORPORATION shall mean Large Scale Biology Corporation, a
California corporation, and any corporate successor to all or substantially all
of the assets or voting stock of Large Scale Biology Corporation that shall by
appropriate action adopt the Plan.

             G. EFFECTIVE TIME shall mean the time at which the Underwriting
Agreement is executed and the Common Stock priced for the initial public
offering of such Common Stock. Any Corporate Affiliate that becomes a
Participating Corporation after such Effective Time shall designate a subsequent
Effective Time with respect to its employee-Participants.

             H. ELIGIBLE EMPLOYEE shall mean any person who is employed by a
Participating Corporation on a basis under which he or she is regularly expected
to render more than twenty (20) hours of service per week for more than five (5)
months per calendar year for earnings considered wages under Code Section 3401
(a).

             I. 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) For purposes of the initial offering period that
        begins at the Effective Time, the Fair Market Value shall be deemed to
        be equal to the price per share at which the Common Stock is sold in the
        initial public offering pursuant to the Underwriting Agreement.

             J. 1933 ACT shall mean the Securities Act of 1933, as amended.

             K. PARTICIPANT shall mean any Eligible Employee of a Participating
Corporation who is actively participating in the Plan.

             L. PARTICIPATING CORPORATION shall mean the Corporation and such
Corporate Affiliate or Affiliates as may be authorized from time to time by the
Board to extend


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the benefits of the Plan to their Eligible Employees. The Participating
Corporations in the Plan are listed in attached Schedule A.

             M. PLAN shall mean the Corporation's 2000 Employee Stock Purchase
Plan, as set forth in this document.

             N. PLAN ADMINISTRATOR shall mean the committee of two (2) or more
Board members appointed by the Board to administer the Plan.

             O. PURCHASE DATE shall mean the last business day of each Purchase
Interval. The initial Purchase Date shall be January 31, 2001.

             P. PURCHASE INTERVAL shall mean each successive six (6)-month
period within a particular offering period at the end of which there shall be
purchased shares of Common Stock on behalf of each Participant.

             Q. STOCK EXCHANGE shall mean either the American Stock Exchange or
the New York Stock Exchange.

             R. UNDERWRITING AGREEMENT shall mean the agreement between the
Corporation and the underwriter or underwriters managing the initial public
offering of the Common Stock.


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