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                              EMPLOYMENT AGREEMENT

     This Employment Agreement dated January 25, 1999 (the "Agreement") is
entered into by and among Large Scale Biology Corporation, a Delaware
corporation ("LSB"), Biosource Technologies, Inc., a California corporation
("Biosource"), and N. Leigh Anderson (the "Employee"). With respect to the terms
of this Agreement the "Employer" shall be LSB unless and until LSB is
consolidated into Biosource at which time the Employer shall be Biosource. The
terms of this Agreement shall take effect on the "Effective Date" which shall be
the Closing Date as such term is defined in the Agreement and Plan of
Reorganization between Biosource and LSB.

     1. Employment. The Employee is hereby employed as President and Chief
Executive Officer of LSB and, if LSB is consolidated into Biosource, then as the
chief executive of the successor entity of LSB in Biosource. The Employee hereby
accepts such employment with the Employer upon the terms and subject to the
conditions set forth herein.

     2. Duties and Responsibilities. The Employee shall perform the services to
Employer and functions relating to the office or offices in which Employee is
from time to time appointed or as are otherwise reasonably incident to such
office or offices. Employee shall be a corporate officer of Biosource and shall
report directly to the Chief Executive Officer of Biosource. The Employee will
devote Employee's best efforts and all necessary time and attention to the
performance of all duties under this Agreement. The employment relationship
between the parties shall be governed by the general employment policies or
practices of the Employer, as adopted or revised from time to time by the
Employer.

     3. Compensation and Other Employee Benefits. Employee's compensation and
benefits will be reviewed periodically and adjusted consistent with Employer's
policies and practices with respect to its senior personnel. As compensation for
Employee's services under the terms of this Agreement:

                  (a) The Employee shall be paid a salary in the amount
         specified on the attached Schedule A (such salary is herein referred to
         as the "Base Salary") payable monthly, less applicable tax withholding,
         which covers all hours worked.

                  (b) The Employee shall receive stock options of the Employer
         (or parent corporation of Employer, the "Parent") in the amount and at
         such time or times as may be specified from time to time by the
         Employer or Parent in their discretion.

                  (c) The Employee may have the opportunity to earn additional
         compensation (the "Additional Compensation") in the amount and at such
         time or times as may be specified from time to time by the Employer in
         its sole discretion. The Base Salary and the Additional Compensation
         are collectively referred to as the "Total Compensation."

                  (d) Subject to the right of the Employer to amend or terminate
         any employee and/or group or senior executive benefit or bonus plan or
         program, and to the terms and

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         conditions of such plans and programs, the Employee shall be entitled
         to receive the following employee benefits:

                            (i) The Employee shall have the right to participate
                   in such employee plans as are maintained by the Employer and
                   are available to its exempt salaried employees generally
                   (including, without limitation, retirement, disability,
                   accident, medical, dental, life insurance and hospitalization
                   plans, to the extent such plans are provided);

                            (ii) The Employee shall be entitled to reimbursement
                   from the Employer for reasonable out-of-pocket expenses
                   incurred by Employee in the course of the performance of
                   Employee's duties hereunder, subject to the submission of
                   reasonable documentation by the Employee and in accordance
                   with the Employer's practices and policies for such
                   reimbursements; and

                            (iii) The Employee shall be entitled to vacation
                   days and holiday pay in accordance with the policies
                   applicable to the Employer's key employees generally.

     4. Term. The term of this Agreement shall commence on the Effective Date
hereof and be for a period of five (5) years, unless terminated pursuant to
Section 5 below.

     5. Termination. Notwithstanding any other provision in this Agreement:

                  (a) Death. If the Employee dies during the term of this
         Agreement and while in the employ of the Employer, this Agreement shall
         automatically terminate as of the date of the Employee's death; and the
         Employer shall have no further obligation to the Employee or his
         estate.

                  (b) Disability. If, during the term of this Agreement, the
         Employee is unable to perform his duties hereunder as a result of any
         physical or mental disability which continues for one hundred eight
         (180) days in any three hundred sixty-five (365) day period, then the
         Employer may terminate this Agreement upon written notice to Employee.

                  (c) Termination for Cause by the Employer. At any time during
         the term of this Agreement, Employer may, upon written notification to
         the Employee, discharge the Employee for cause and terminate this
         Agreement without any further liability hereunder to the Employee or
         his estate.

     6. Confidentiality. For the period during which the Employee is employed by
the Employer and thereafter (regardless of the reason for termination of
employment), the Employee will not divulge, except to employees, directors and
officers of Employer and such others as may reasonably need to know in order for
Employee to perform his work hereunder or, except pursuant to Section 8 hereof,
appropriate to Employee's own use or to the use of others any secret,
confidential or proprietary information pertaining to the business of the
Employer or any subsidiary or affiliate of Employer (including without
limitation, trade secrets, technology, know how, designs, specifications,
software, source code, protocols, algorithms, business strategies or

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plans, or other intellectual property), unless first approved in writing by
Employer. For purposes of this Agreement, the term secret, proprietary or
confidential information does not include any information that is or becomes
generally available to and known by the public (other than as a result of an
unpermitted disclosure directly or indirectly by the Employee or any third
party).

     7. Noncompetition. Employee agrees to the restrictions set forth in this
Section 7, which restrictions the Employee agrees are reasonable in light of the
consideration provided to Employee pursuant to this Agreement. Except as
provided in Section 8 below the Employee shall not, for the term of this
Agreement, directly or indirectly, as an owner, partner, shareholder except to
the extent specified herein, director, consultant, agent, employee or
co-venturer of any Person (as defined herein), compete commercially in the
Employer Business (as defined herein). For purposes of this Agreement, (a) the
term "Employer Business" shall mean the businesses of LSB and Biosource
including the business of (i) making or having made, designing, developing,
manufacturing, selling or having sold, buying, acquiring, licensing, leasing,
furnishing, or maintaining or using products, including diagnostics, diagnostic
markers, novel targets for drug discovery, drug combinations, improved drugs,
related software, hardware, instruments or machines, and processes related to
researching, finding, isolating, analyzing, identifying, and characterizing
proteins; (ii) researching, finding, isolating, analyzing, identifying, and
characterizing proteins, characterizing disease processes at the protein level
by the systematic study of the protein complement of an organism, and/or
compiling protein databases, in each case for commercial purposes; (iii) leasing
or selling instruments, systems, protein databases and related research services
anywhere in the world (nothing in this definition is intended to narrow the
recognition that the products and processes and databases developed by Employer
may have applicability beyond their uses in association with proteins and would
be used, sold or leased within the scope of Employer Business for all such
uses), and (b) the term "Person" shall mean an individual, a corporation, an
association, a partnership, an estate, a trust and any other entity or
organization. The Employee may purchase a passive investment representing an
interest of less than five percent (5%) of any outstanding class of shares of
any Person competing in the Employer Business (i) if the class or series is
listed on a national or regional securities exchange or publicly traded in the
"over-the-counter" market or (ii) with the consent of Employer, which shall not
be unreasonably withheld.

     8. Technology Rights. Employee shall have rights as follows ("Technology
Rights") if within two (2) years of the Effective Date hereof (i) Employee's
employment is terminated by Employer other than for cause, or (ii) the Employee
resigns under circumstances where (a) Robert L. Erwin is no longer Chief
Executive Officer of Biosource and/or (b) the investment to be made in LSB
product and technology development by Biosource from Biosource's separate funds
is not made in such amounts and/or on such schedule as is reasonable and
sufficient to finance said development at the rate of $8million over such two
years as stated in the Biosource Information Statement relative to the
acquisition of shares of capital stock of LSB. In the event of the departure of
the Employee by termination or resignation under terms described in the
preceding sentence, the Employer shall on the date of such departure grant to
the Employee a paid-up, irrevocable, worldwide license to freely practice and
use all technology, software and data owned by or assigned to LSB prior to the
Effective Date hereof ("Pre-Existing Technology"); provided, however, that for
the remaining term of this Agreement such practice and use shall not compete
commercially with the Employer Business as defined herein or, with respect to
any license or assignment of the Pre-Existing Technology made prior to said

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departure, with the business of any such licensee or assignee in the field in
which such license or assignment of the Pre-Existing Technology was made. The
Employee hereby agrees to forego his Technology Rights in the sole instance
where, prior to any exercise thereof by Employee, Biosource shall have commenced
the registration process with respect to an initial public offering for not less
than $15million and, in such instance, only on condition that the Technology
Rights be immediately restored if for any reason said public offering is
withdrawn.

     9. Form of Remedy and Continuing Provisions. The Employee acknowledges that
the Employer would be irreparably injured by a violation of Section 6 and 7 and
that the Employer would have no adequate remedy at law in the event of such
violation. Therefore, the Employee acknowledges and agrees that, in addition to
any other remedies available, injunctive relief, specific performance or any
other appropriate equitable remedy (without any bond or other security being
required) are appropriate remedies of the Employer to enforce compliance with
Section 6 and 7. The provisions of Section 6 and 7 shall continue in effect,
notwithstanding the termination of Employee's employment or any other
termination of this Agreement.

     The Employer acknowledges that the Employee would be irreparably injured by
a violation of Section 8 by Employer and that the Employee would have no
adequate remedy at law in the event of such violation. Therefore, the Employer
acknowledges and agrees that, in addition to any other remedies available,
injunctive relief, specific performance or any other appropriate equitable
remedy (without any bond or other security being required) are appropriate
remedies of the Employee to enforce compliance with Section 8. The provisions of
Section 8 shall continue in effect, notwithstanding the termination of
Employee's employment or any other termination of this Agreement.

     10. Entire Agreement; Amendments; Waivers. This Agreement, together with
the Proprietary Information and Inventions Agreement attached hereto as Exhibit
A and made a part hereof, contains the entire agreement of the Employee, LSB and
Biosource relating to the matters contained herein and supersedes all prior
agreements and understandings, oral or written, between said parties with
respect to the subject matter hereof. To the extent that the terms of this
Agreement and Exhibit A hereto conflict, the terms of this Agreement shall
prevail. This Agreement may be amended, modified or supplemented, but only in
writing signed by each of the parties hereto. Any term of this Agreement may be
waived only with the written consent of the party sought to be bound, and the
waiver by any party to this Agreement of a breach of any provision of the
Agreement by another party shall not operate or be construed as a waiver by such
party of any subsequent breach by such other party.

     11. Reformation and Severability. In case any provision of this Agreement
shall be invalid, illegal or unenforceable, it shall, to the extent possible, be
modified in such manner as to be valid, legal and enforceable but so as to most
nearly retain the intent of the parties, and if such modification is not
possible, such provision shall be severed from this Agreement, and in either
case the validity, legality and enforceability of the remaining provisions of
this Agreement shall not in any way be affected or impaired thereby.

     12. Assignments. The Employer may assign this Agreement to any person or
entity succeeding to all or substantially all of the business interests of the
Employer by merger or otherwise. The rights and obligations of the Employee
under this Agreement are personal to

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Employee, and no such rights, benefits or obligations shall be subject to
voluntary or involuntary alienation, assignment or transfer, except as otherwise
contemplated hereby.

     13. Effect of Agreement. Subject to the provisions of Section 12 of this
Agreement with respect to assignments, this Agreement shall be binding upon the
Employee and Employee's heirs, executors, administrators, legal representatives
and assigns and upon LSB, Biosource and their respective successors and assigns.

     14. Exercise of Rights and Remedies. No delay of or omission in the
exercise of any right, power or remedy accruing to any party as a result of any
breach or default by any other party under this Agreement shall impair any such
right, power or remedy, nor shall it be construed as a waiver of or acquiescence
in any such breach or default, or of any similar breach or default occurring
later.

     15. Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the state of Maryland, notwithstanding choice of law
rules.

     16. Litigation & Arbitration Costs. If any legal proceeding or arbitration
is necessary to enforce or interpret the terms of this Agreement, or to recover
damages for breach hereof, the substantially prevailing party shall be entitled
to reasonable attorneys' fees, as well as its costs and disbursements, in
addition to any other relief to which it may be entitled.

     17. Arbitration. In the event of a dispute between or among the parties
hereto regarding the terms and conditions of this Agreement ("Dispute"), said
parties shall attempt in good faith to resolve the Dispute within five (5)
calendar days. If, after such time, the parties are unable to resolve the
Dispute, the parties shall submit to arbitration conducted by JAMS/Endispute in
San Francisco, California (which submission shall be accompanied by a demand for
arbitration under applicable arbitration rules). Such arbitration shall be
conducted before a single arbitrator selected by agreement of the parties hereto
in accordance with the rules of JAMS/Endispute Comprehensive Rules of
Commercial, Real Estate and Construction Cases (www.jamsendispute.com). If the
parties are unable to agree to a single arbitrator within three (3) calendar
days of demand for arbitration, JAMS/Endispute shall appoint the arbitrator who
shall be experienced with resolving corporate employer-employee disputes. The
arbitrator shall not be empowered to award damages in excess of compensatory
damages and the arbitration shall be resolved within thirty (30) calendar days
of its initiation. Judgment upon any decision rendered by the arbitrator may be
entered by any court having jurisdiction. The procedures set forth in this
Section 17 are the sole and exclusive procedures for the resolution of disputes
among the parties arising out of or related to this Agreement; provided,
however, that any party may seek a preliminary injunction or other provisional
judicial relief if, in its sole judgment, such action is necessary to avoid
irreparable damage or to preserve the status quo. All pending court action shall
be stayed and all applicable statutes of limitation and defenses based on the
passage of time shall be tolled while alternative dispute resolution efforts are
pursued. The parties shall take such action, if any, necessary to effectuate
such stay or tolling.

     18. Execution. This Agreement may be executed in two or more counterparts,
each of which shall be deemed an original and all of which together shall
constitute but one and the same instrument.

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     IN WITNESS WHEREOF, LSB, Biosource and N. Leigh Anderson have executed this
Agreement



Large Scale Biology Corporation        N. Leigh Anderson:


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Signature                              signature


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Name


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Title



Biosource Technologies, Inc.


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Signature


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Name


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Title


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                                   SCHEDULE A

                                       TO

                              EMPLOYMENT AGREEMENT

                             WITH N. LEIGH ANDERSON

                                  Compensation






Base Salary: $185,000 per annum


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