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                                                                   EXHIBIT 10.51

                  EXECUTIVE EMPLOYMENT AND SEVERANCE AGREEMENT

     This Executive Employment and Severance Agreement ("Agreement") is made
effective as of December 5, 2002 ("Effective Date"), by and between Invitrogen
Corporation ("Company") and James R. Glynn ("Executive").

                                    RECITALS

     A.   Executive has been employed as Company's Executive Vice President.

     B.   Executive and Company are parties to a Change-in-Control Agreement
dated June 1, 2001 ("Change-in-Control Agreement"), which provides for a
severance package in certain circumstances in connection with a
Change-in-Control (as that term is defined below).

     C.   Executive has been granted stock options to purchase shares of
Company's common stock pursuant to Company's stock option plans and stock option
agreements as set forth in Section 4 below.

     D.   Executive and Company desire to redefine and transition Executive's
role and supersede the Change-in-Control Agreement in its entirety.

     The parties agree as follows:

     1.   Duties.

          1.1  Position. Effective December 5, 2002, Executive is promoted to
President and Chief Operating Officer of the Company. Effective January 1, 2003,
Executive shall also hold the position of Chief Executive Officer ("CEO") of the
Company. Executive will run day-to-day operations of Company and shall have
other duties and responsibilities to be determined in consultation with
Company's Board of Directors ("Board of Directors"). Executive will also be
responsible for assisting in the recruitment and selection process for a new CEO
and will assist in the transition process after the new CEO is appointed by the
Board of Directors, if requested. Executive shall perform faithfully,
cooperatively and diligently all of his job duties and responsibilities.

          1.2  Best Efforts. Executive will expend his best efforts on behalf of
Company, and will abide by all policies and decisions made by Company, as well
as all applicable federal, state and local laws, regulations or ordinances.
Executive will act in the best interest of Company at all times.

     2.   At-Will Employment Relationship. Executive's employment with Company
is at-will and not for any specified period and may be terminated by either
Executive or Company at any time, with or without cause. No representative of
Company, other than an authorized member of the Board of Directors, has the
authority to alter the at-will employment relationship. Any change to the
at-will employment relationship must be by specific, written agreement signed
by Executive and an authorized member of the Board of Directors. Nothing in
this Agreement is intended to or should be construed to contradict, modify or
alter this at-will relationship.




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     3.   Compensation.

          3.1  Base Salary. As compensation for Executive's performance of his
duties hereunder, Company shall pay to Executive a base salary of $41,666 per
month ($500,000 annually)("Annual Base Salary"), payable in accordance with the
normal payroll practices of Company, less required deductions for state and
federal withholding tax, social security and all other employment taxes and
payroll deductions. Adjustments to Annual Base Salary or any other
compensation, if any, will be made by the Board of Directors' Compensation and
Organization Committee in its discretion. If Executive's employment under this
Agreement is terminated by either party, for any reason, Company will pay
Executive: (a) the Annual Base Salary through the Date of Termination (as
defined below); (b) the product of (x) Executive's annual bonus earned under
Invitrogen's incentive compensation plan for senior executives, if any (the
"Annual Bonus"), and (y) a fraction, the numerator of which is the number of
days in the current fiscal year through the Date of Termination, and the
denominator of which is 365; (c) any compensation previously deferred by
Executive (together with any accrued interest thereon) and not yet paid by
Company; and (d) any accrued but unused vacation not yet paid by Company.

          3.2  Incentive Compensation/Savings/Retirement. In addition to Annual
Base Salary and Annual Bonus payable as hereinabove provided, Executive shall be
entitled to participate in all incentive compensation, savings and retirement
plans, practices, policies and programs generally applicable to senior level
executives of Company that are in effect during Executive's employment with
Company.

     4.   Stock Options.

          4.1  Unchanged. The following stock options previously granted to
Executive by Company will continue to vest throughout the term of this
Agreement and, to the extent not already exercised, shall be exercisable
following termination of Executive's employment only to the extent allowed
under the terms of the applicable stock option plan and stock option agreement:


OPTION NUMBERS      SHARES         PRICE          OPTION DATE

005056             100,000         $34.51         9-6-2002
005885              50,000         $31.33         12-19-2002
005883                 455         $27.68         12-5-2002
005884              49,545         $27.68         12-5-2002
000155              89,285         $ 5.60         6-15-1998
000156             160,715         $ 5.60         6-15-1998

          4.2  Accelerated Vesting and Extended Post-Employment Exercise
Period. The following stock options previously granted to Executive by Company
shall immediately vest and become exercisable on the date this Agreement is
executed by the parties, and such stock options shall be exercisable at any
time on or before December 31, 2007:

OPTION NUMBERS      SHARES         PRICE          OPTION DATE

004408                 625         $45.64         2-28-2002

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004409               9,375         $45.64         2-28-2002
002393                 833         $70.688        1-4-2001
002394              49,167         $70.688        1-4-2001
000902                 124         $75.203        7-1-2000
000903              49,876         $75.203        7-1-2000
000446               5,345         $54.375        1-4-2000
000447              94,655         $54.375        1-4-2000
000834                  37         $60.00         1-1-2000
000835               2,184         $60.00         1-1-2000

Company shall provide to Executive an original Secretary's Certificate that
attaches a copy of a Unanimous Written Consent of the Compensation and
Organization Committee of the Board of Directors in the form attached hereto as
Exhibit A, amending the stock option agreements between Company and Executive
related to the options listed above in this Section 4.2 (the "Modified
Options"), dated as of the date of the execution of this Agreement. If on the
date of execution of this Agreement, the closing price of Company's common stock
on the NASDAQ stock market is higher than the exercise price of any of the
Modified Options (which will hereafter be referred to as being "in the money"),
then the Consulting Fee set forth in Section 9.1(a) below shall be reduced by an
amount equal to the product of the equation X x Y, where X is the number of the
Executive's stock options that are in the money and Y is the amount by which
Executive's stock options are in the money. For example, if on the date of the
execution of this Agreement, the closing price of Company's common stock on the
NASDAQ stock market is $47.00, the Consulting Fee would be reduced by $10,001.36
(10,000 x $1.36 = $10,001.36).

     5.   Health and Welfare Benefit Plans. During Executive's employment,
Executive and/or Executive's family, as the case may be, shall be eligible for
participation in and shall receive all benefits under health and welfare
benefit plans, practices, policies and programs provided by Company (including,
without limitation, medical prescription, dental disability, salary
continuance, employee life, group life, accidental death and travel accident
insurance plans and programs) to the extent generally applicable to senior
level executives of Company subject to the terms and conditions of Company's
benefit plan documents, policies or programs. Company reserves the right to
change or eliminate Company's benefit plans, practices, policies or programs on
a company-wide, prospective basis, at any time.

     6.   Customary Fringe Benefits. Executive shall be entitled to all
customary and usual fringe benefits generally available to senior level
executives of Company subject to the terms and conditions of Company's benefit
plan documents, policies or programs. Company reserves the right to change or
eliminate the fringe benefits on a company-wide, prospective basis, at any time.

     7.   Business Expenses. Executive shall be entitled to receive prompt
reimbursement for all reasonable, out-of-pocket business expenses incurred in
the performance of his duties on behalf of Company. To obtain reimbursement,
expenses must be submitted promptly with appropriate supporting documentation
in accordance with Company's policies.

     8.   Vacation. Executive shall be entitled to paid vacation in accordance
with the plans, policies, programs of Company as in effect for senior level
executives of Company.

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     9.   Consulting and Severance Package Upon Termination of Employment.
Although employment between Executive and Company is at-will, and either
Executive or Company may terminate the employment relationship at any time with
or without cause, Company agrees to provide Executive with the Consulting and
Severance Package described in Section 9.1 below, under the circumstances
described in Section 9.2 below, provided Executive agrees to comply with all
the conditions set forth in Section 9.4 below.

          9.1  Description of Consulting and Severance Package. The "Consulting
and Severance Package" will consist of:

               (a)  engagement as a consultant where Executive will be paid a
"Consulting Fee" equal to the sum of (x) 2.0 times Executive's Annual Base
Salary (the "Base Salary Portion") plus (y) the product of (i) the Base Salary
Portion, multiplied by (ii) 0.35; and

               (b)  For a period of two (2) years following the Date of
Termination, or such longer period as any plan, program, practice or policy may
provide (the "Benefits Continuation Period"), Company shall continue health and
welfare benefits to Executive and, where applicable, Executive's family, at
least equal to those which would have been provided to them in accordance with
the plans, programs, practices and policies described in Section 5 of this
Agreement if the Executive's employment had not been terminated, in accordance
with the most favorable plans, practices, programs or policies of the Company
generally applicable to senior level executives of the Company and their
families during the ninety (90) day period immediately preceding the Date of
Termination or, if more favorable to the Executive, as in effect at any time
thereafter generally with respect to other senior level executives of the
Company and their families. To the extent Company's health and welfare benefit
plans do not allow Company to continue such benefits for Executive once he is no
longer employed by Company, Company agrees to pay the premiums required to
continue: (i) Executive and Executive's family's group health and dental care
coverage for eighteen (18) months under the applicable provisions of the
Consolidated Omnibus Budget Reconciliation Act of 1985 ("COBRA"), provided that
Executive elects to continue and remains eligible for these benefits under
COBRA. After Executive's COBRA coverage has ended, Company will pay Executive a
monthly amount equivalent to the monthly premium Company paid for Executive and
Executive's family's group health and dental care coverage during Executive's
employment for six (6) additional months; and (ii) Executive's coverage under
other insurance policies during the Benefits Continuation Period to the extent
Executive elects to convert these policies to individual policies.
Notwithstanding the above, in the event Executive becomes employed elsewhere
during the Benefits Continuation Period provided for herein and is thereby
afforded comparable insurance and health and welfare benefits to those described
in Section 5 of this Agreement, the Company's obligation to continue providing
the Executive with such benefits or monetary equivalent of premiums shall cease
or be correspondingly reduced, as the case may be.

The amounts payable to Executive pursuant to this Agreement will not be subject
to any requirement of mitigation, nor, except as specifically set forth in this
Agreement, will they be offset or otherwise reduced by reason of Executive's
receipt of compensation from any source other than Company.

          9.2  Termination Circumstances Upon Which Consulting and Severance
Package Will Be Paid. In all circumstances other than a termination for Cause
and provided Executive satisfies the conditions set forth in Section 9.4 below,
Executive will be entitled to the

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Consulting and Severance Package upon a termination or resignation following
the earliest to occur of any of the following (each of which is referred to as
a "Triggering Event"):

          (a)  a Change in Control;

          (b)  the date that is thirty (30) consecutive days after the
               appointment by the Board of Directors of a new CEO; or

          (c)  June 30, 2003.

In addition, Executive, or Executive's estate, will receive the Consulting and
Severance Package if his employment is terminated without Cause or due to his
death or Disability (as defined below), or Executive resigns for Good Reason
(as defined below) prior to the occurrence of any of the Triggering Events. The
Consulting and Severance Package will be paid only once following the
termination of Executive's employment as a result of the Triggering Events or a
termination for Cause, a termination due to death or Disability or a
resignation for Good Reason. In no circumstance shall Executive receive the
Consulting and Severance Package on more than one occasion, even if one or more
of the Triggering Events subsequently occur.

     9.3  Payment Schedule.  The Consulting and Severance Package will be paid
less required deductions for state and federal withholding tax, social security
and all other employment taxes as required by law. The Consulting Fee described
in section 9.1(a) will be paid in accordance with the following schedule: 25%
of the Consulting Fee will be paid on the Date of Termination and the remaining
75% will be paid in eight equal quarterly installments over the course of two
(2) years following the Date of Termination (the "Consulting Period"), with the
first installment to be paid on or before the last day of the first calendar
quarter that ends at least sixty (60) days after the Date of Termination and
with the subsequent installments to be paid, respectively, on or before the
last day of the next seven calendar quarters thereafter.

     9.4  Conditions to Receive Consulting and Severance Package.  Executive
will receive the Consulting and Severance Package described above only if he
complies with all of the following conditions:

          (a)  executes a Confidential Separation Agreement and General Release
of All Claims in the form attached hereto as Exhibit B (the "Release");

          (b)  remains available on reasonable notice during the Consulting
Period and, if requested, serves as a strategic consultant for Company (at
times reasonable to Executive and Company), for up to ten (10) hours per month,
in accordance with the terms and conditions of an Independent Contractor
Services Agreement in the form attached hereto as Exhibit C (the "Contractor
Agreement"), in exchange for the Consulting Fee described above; and

          (c)  complies with the Trade Secrets New Employee Orientation
Agreement dated June 15, 1998 and the Employee's Agreement Relating to Company
Information and Technology dated June 15, 1998 he signed in connection with his
employment and complies with the Company's Insider Trading Policy executed by
Executive contemporaneously with the execution of this Agreement (collectively
referred to as the "Confidentiality Agreements") during any consulting
engagement and complies with all surviving provisions of the Confidentiality
Agreements once the consulting engagement ends;


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               (d)  during the term of this Agreement and any period of time
Executive is consulting for Company or receiving payments from Company, and due
to Executive's exposure to Company's trade secrets and other confidential and
proprietary information, Executive agrees not to engage in any work, paid or
unpaid, enter into a contract, provide financial support, or accept an
obligation inconsistent with his obligations under this Agreement or the
Contractor Agreement, as the case may be, including but not limited to, directly
or indirectly competing with Company in any way, including, without limitation,
engaging in competitive research and development activities, or acting as an
officer, director, partner, manager, employee, consultant, stockholder,
volunteer, lender, principal or agent of any business enterprise of the same
nature as, or which is in direct competition with, any business in which Company
is now engaged or in which Company becomes engaged during Executive's employment
with Company or any period of time Executive is engaged as a consultant by
Company, as may be determined by the Board of Directors in its discretion. In
addition, Executive agrees not to refer any client or potential client of
Company to competitors of Company, without obtaining Company's prior written
consent, during the term of this Agreement and any period of time Executive is
consulting for Company or receiving payments from Company. Notwithstanding the
above, Executive is permitted to own up to one percent (1%) of the listed or
traded stock of any publicly held corporation. For purposes of this Section
9.4(d), the term "Company" shall mean and include Company, any subsidiary or
affiliate of Company and any successor to the business of Company (by merger,
consolidation, sale of assets or stock or otherwise).

               (e)  Notwithstanding any other provision of this Agreement,
Executive shall be entitled to receive the Consulting and Severance Package upon
his execution and delivery to the Company of the Release and the Contractor
Agreement, regardless of whether the Company executes and delivers the Release
and/or the Contractor Agreement, provided he satisfies all of the other
conditions described in Section 9.4 above and set forth in the Release and the
Contractor Agreement.

     10.  Definitions.

          10.1 Cause. For purposes of this Agreement, "Cause" shall mean any of
the following acts occurring after the Effective Date of this Agreement: (a)
repeated violations by Executive of Executive's responsibilities and duties
under Section 1 of this Agreement which are demonstrably willful and deliberate
on Executive's part and which are not remedied in a reasonable period of time
after receipt of written notice from Company; (b) commission of an intentional
act of fraud, embezzlement or theft by Executive in connection with Executive's
duties or in the course of Executive's employment with Company or its affiliated
companies; (c) causing intentional wrongful damage to property of Company or its
affiliated companies; (d) intentionally and wrongfully disclosing secret
processes or confidential information of Company or its affiliated companies; or
(e) participating, without Company's express written consent, in the management
of any business enterprise which engages in substantial and direct competition
with Company or its affiliated companies, and any such act shall have been
materially harmful to Company or its affiliated companies.

          10.2 Change-in-Control. For purposes of this Agreement, a
"Change-in-Control" shall mean:

               (a)  Any acquisition or series of acquisitions, other than from
Company, by any individual, entity or group (within the meaning of Section
13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934, as amended (the
"Exchange Act")) of beneficial

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ownership (within the meaning of Rule 13d-3 under the Exchange Act) of 50% or
more of either the then outstanding shares of common stock of Company (the
"Outstanding Company Common Stock") or the combined voting power of the then
outstanding voting securities of Company entitled to vote generally in the
election of directors (the "Outstanding Company Voting Securities"), provided,
however, that: (i) any acquisition by Company, or any of its subsidiaries; (ii)
any acquisition by any employee benefit plan (or related trust) sponsored or
maintained by Company or any of its subsidiaries; or (iii) any acquisition or
series of acquisitions which results in any individual, entity or group (within
the meaning of Section 13(d)(3) or 14(d)(2) of the Exchange Act) acquiring
beneficial ownership (within the meaning of Rule 13d-3 under the Exchange Act)
of more than 50% of the Outstanding Company Common Stock and while such a
beneficial owner such individual, entity or group does not exercise the voting
power of his, her or its Outstanding Company Common Stock or otherwise exercise
control with respect to any matter concerning or affecting Company and promptly
sells, transfers, assigns or otherwise disposes of that number of shares of
Outstanding Company Common Stock necessary to reduce his, her or its beneficial
ownership (within the meaning of Rule 13d-3 under the Exchange Act) of the
Outstanding Company Common Stock to below 50%, as the case may be, shall not
constitute a Change-in-Control; or

               (b)  Individuals who as of April 27, 2001, constitute the Board
of Directors of Company (the "Incumbent Board") cease for any reason to
constitute at least a majority of the Board of Directors of Company, provided
that any individual becoming a director subsequent to April 27, 2001, whose
election, or nomination for election, by Company's stockholders was approved by
a vote of at least a majority of the directors then comprising the Incumbent
Board, shall be considered as though such individual were a member of the
Incumbent Board, but excluding, for this purpose, any such individual whose
initial assumption of office is in connection with an actual or threatened
election contest (as such terms are used in Rule 14a-11 of the Regulation 14A
promulgated under the Exchange Act) relating to the election of directors of
Company; and


               (c)  Approval by the stockholders of Company of a complete
liquidation or dissolution of Company, or of the sale or other disposition of
all or substantially all of the assets of Company, or of a reorganization,
merger or consolidation of Company, in each case, with respect to which all or
substantially all of the individuals and entities who were the respective
beneficial owners of the Outstanding Company Common Stock and Outstanding
Company Voting Securities immediately prior to such reorganization, merger or
consolidation do not, following such reorganization, merger or consolidation
beneficially own, directly or indirectly, more than 60% of, respectively, the
then outstanding shares of common stock and the combined voting power of the
then outstanding voting securities entitled to vote generally in the election
of directors, as the case may be, of the corporation resulting from such
reorganization, merger or consolidation.

          10.3 Disability. For purposes of their Agreement, "Disability" shall
mean the absence of Executive from Executive's duties with Company on a
full-time basis for 180 consecutive business days as a result of incapacity due
to mental or physical illness which is determined to be total and permanent by a
physician selected by Company or its insurers and acceptable to Executive or
Executive's legal representative (such agreement as to acceptability not to be
withheld unreasonably).

          10.4 Good Reason. For purposes of this Agreement, "Good Reason" shall
mean:


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            (a)   any failure by Company to comply with any of the provisions of
Section 3 of this Agreement, other than an isolated, insubstantial and
inadvertent failure not occurring in bad faith and which is remedied by Company
promptly after receipt of written notice thereof given by Executive;

            (b)   Company requiring Executive to be based at any office or
location other than Carlsbad, California or requiring Executive to travel away
from his or her office in the course of discharging responsibilities or duties
in a manner which is inappropriate for the performance of Executive's duties
hereunder and which is significantly more frequent (in terms of either
consecutive days or aggregate days in any calendar year) than was required
prior to the Effective Date of this Agreement.

            (c)   any purported termination by Company of Executive's
employment otherwise than as expressly permitted by this Agreement; or

            (d)   any failure by any successor to Company to comply with and
satisfy Section 19.1 of this Agreement, provided that such successor has
received at least ten (10) days prior written notice from Company or Executive
of the requirements of Section 19.1 of this Agreement.

      11. Notice of Termination.  Any termination by Company for Cause or by
Executive for Good Reason shall be communicated by "Notice of Termination" to
the other party hereto given in accordance with Section 19.7 of this Agreement.
For purposes of this Agreement, a "Notice of Termination" means a written
notice which: (a) indicates the specific termination provision in this
Agreement relied upon; (b) to the extent applicable, sets forth in reasonable
detail the facts and circumstances claimed to provide a basis for termination of
Executive's employment under the provision so indicated; and (c) if the Date of
Termination (as defined below) is other than the date of receipt of such
notice, specifies the termination date (which date shall be not more than
fifteen days after the giving of such notice). The failure by Executive or
Company to set forth in the Notice of Termination any fact or circumstance
which contributes to a showing of Good Reason or Cause, as the case may be,
shall not waive any right of Executive or Company hereunder or preclude
Executive or Company from asserting such fact or circumstance in enforcing
Executive's or Company's rights hereunder. Any termination by Company without
Cause or by Executive without Good Reason must be preceded by thirty (30) days'
advance written notice in accordance with the terms of Section 19.7 of this
Agreement.

      12. Date of Termination.  "Date of Termination" means the first to occur
of:
          12.1    the date of the first to occur of any Triggering Event, as
set forth in Section 9.2 above; or

          12.2    the date of receipt of the Notice of Termination (i.e.,
termination for Cause or for Good Reason) or any later date specified therein,
as the case may be; or

          12.3    Executive's death; or

          12.4    the effective date of Executive's Disability; or

          12.5    thirty (30) days after the date on which Company notifies
Executive of termination not addressed in Subsections 12.1-12.4 above; or


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     12.6 thirty (30) days after the date on which Executive notifies Company of
his resignation other than for Good Reason.

     13.  Confidentiality and Proprietary Rights. Executive agrees to continue
to abide by the Confidentiality Agreements, which are provided with this
Agreement at Exhibit D and incorporated herein by reference.

     14.  Nonsolicitation. Executive understands and agrees that Company's
employees and customers and any information regarding Company's employees and/or
customers is confidential and constitutes trade secrets. Accordingly, Executive
agrees that during the term of this Agreement, during the consulting engagement
and for a period of one (1) year after the termination of the consulting
engagement, Executive will not, either directly or indirectly, separately or in
association with others: (a) interfere with, impair, disrupt or damage Company's
relationship with any of its customers, customer prospects, vendors,
contractors, collaborators, joint venturers, partners, licensors, or licensees
by soliciting or encouraging others to solicit any of them for the purpose of
diverting or taking away business or opportunities from Company; or (b)
interfere with, impair, disrupt or damage Company's business by soliciting or
attempting to hire any of Company's employees or causing others to solicit or
encourage any of Company's employees to discontinue their employment with
Company; provided, however, that Executive being named as a referral on the
resume of a Company employee and Executive responding to inquiries resulting
therefrom shall not violate this Agreement.

     15.  Nondisparagement. Executive agrees not to disparage, defame or make
any negative or critical public statements, whether verbally or in writing,
regarding the personal or business reputation, technology, products, practices
or conduct of Company or any of Company's officers or directors. In addition,
except as required by law, Executive shall not make any public statements
regarding Company without the prior written approval of the Board of Directors.
Likewise, Company agrees that its officers and directors will not disparage,
defame or make negative or critical statements, written or oral, regarding the
personal or business reputation, practices or conduct of Executive.

     16.  Injuctive Relief. Executive acknowledges that Executive's breach of
the covenants contained in Sections 9.4(d)(if applicable) and Sections 13-15
would cause irreparable injury to Company and agrees that in the event of any
such breach, Company shall be entitled to seek temporary, preliminary and
permanent injunctive relief without the necessity of proving actual damages or
posting any bond or other security.

     17.  No Other Severance Benefits. Executive acknowledges and agrees that
the Severance and Consulting Package provided pursuant to this Agreement is in
lieu of any other severance benefits, including but not limited to, severance
pay, salary or bonus continuation or actual or deemed pension or insurance
continuation, for which Executive may be eligible now or in the future under any
other agreement, including the Change-in-Control Agreement, and/or any other
Company severance plan, program or practice.

     18.  Certain Additional Payments by Company.

          18.1 Excise Tax. Anything in this Agreement to the contrary
notwithstanding, in the event it shall be determined that, as a result, directly
or indirectly, of the operation of any of Company's existing stock option plans,
or any successor option or restricted stock plans (collectively, the "Option and
Restricted Stock Acceleration"), either standing alone or taken

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together with the receipt of any other payment or distribution by Company to or
for the benefit of Executive whether paid or payable or distributed or
distributable pursuant to the terms of this Agreement or otherwise (a
"Payment"), Executive would be subject to the excise tax imposed by Section 4999
of the Internal Revenue Code of 1986, as amended (the "Code") or any interest or
penalties are incurred by Executive with respect to such excise tax (such excise
tax, together with any such interest and penalties, are hereinafter collectively
referred to as the "Excise Tax"), then the amount payable to Executive hereunder
or as a result of the Option and Restricted Stock Acceleration shall be reduced
in an amount that would result in Executive being in the most advantageous net
after-tax position (taking into account both income taxes and any Excise Tax).
For purposes of this termination the "base amount" as defined in Section
280(G)(b)(3)(A) of the Code shall be allocated between the Option and Restricted
Stock Acceleration, on the one hand, and Payments, on the other hand, in
accordance with 280G(b)(3)(B) of the Code.

          18.2  Accounting Firm.  All determinations required to be made under
this Section, including the amount of any reduction that will be made in the
payments made pursuant to this Agreement and the assumptions to be utilized in
arriving at such determinations, shall be made by PricewaterhouseCoopers LLP
(the "Accounting Firm") which shall provide detailed supporting calculations
both to Company and Executive. All fees and expenses of the Accounting Firm for
tax and accounting advice provided to Executive, up to a maximum of $15,000,
shall be borne solely by Company. If the Accounting Firm determines that no
Excise Tax is payable by Executive, it shall furnish Executive with an opinion
that failure to report the Excise Tax on Executive's applicable federal income
tax return would not result in the imposition of a negligence or similar
penalty. Any determination by the Accounting Firm shall be binding upon Company
and Executive.

     19.  General Provisions.

          19.1  Successors and Assigns.  The rights and obligations of Company
under this Agreement shall inure to the benefit of and shall be binding upon the
successors and assigns of Company. Executive shall not be entitled to assign any
of Executive's rights or obligations under this Agreement. Company will require
any successor (whether direct or indirect, by purchase, merger, consolidation or
otherwise) to all or substantially all of the business and/or assets of Company
to assume expressly and agree to perform this Agreement in the same manner and
to the same extent that Company would be required to perform it if no such
succession had taken place. As used in this Agreement, "Company" shall mean the
Company as hereinbefore defined and any successor to its business and/or assets
as aforesaid which assumes and agrees to perform this Agreement by operation of
law, or otherwise.

          19.2  Waiver.  Either party's failure to enforce any provision of
this Agreement shall not in any way be construed as a waiver of any such
provision, or prevent that party thereafter from enforcing each and every other
provision of this Agreement.

          19.3  Attorneys' Fees.  Each side will bear its own attorneys' fees
in any dispute unless a statutory section at issue, if any, authorizes the
award or attorneys' fees to the prevailing party.

          19.4  Severability.  In the event any provision of this Agreement is
found to be unenforceable by an arbitrator or court of competent jurisdiction,
such provision shall be deemed modified to the extent necessary to allow
enforceability of the provision as so limited, it being intended that the
parties shall receive the benefit contemplated herein to the fullest extent


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<PAGE>
permitted by law. If a deemed modification is not satisfactory in the judgment
of such arbitrator or court, the unenforceable provision shall be deemed
deleted, and the validity and enforceability of the remaining provisions shall
not be affected thereby.

          19.5  Interpretation; Construction. The headings set forth in this
Agreement are for convenience only and shall not be used in interpreting this
Agreement. This Agreement has been drafted by legal counsel representing
Company, but Executive has participated in the negotiation of its terms.
Furthermore, Executive acknowledges that Executive has had an opportunity to
review the Agreement and has had it reviewed and negotiated by legal counsel
acting on his behalf, and, therefore, the normal rule of construction to the
effect that any ambiguities are to be resolved against the drafting party shall
not be employed in the interpretation of this Agreement.

          19.6  Governing Law. This Agreement will be governed by and construed
in accordance with the laws of the United States and the State of California.
Each party consents to the jurisdiction and venue of the state or federal
courts in San Diego, California, if applicable, in any action, suit, or
proceeding arising out of or relating to this Agreement.

          19.7  Notices. All notices and other communications hereunder shall
be in writing and shall be given by hand delivery to the other party or by
registered or certified mail, return receipt requested, postage prepaid,
addressed as follows:

                    If to Executive:
                    ---------------

                    James R. Glynn
                    1911 Coast Boulevard
                    Del Mar, CA 92014

                    If to the Company:
                    -----------------

                    Invitrogen Corporation
                    1600 Faraday Avenue
                    Carlsbad, CA 92008
                    (ATTN: General Counsel)

or to such other address as either party shall have furnished to the other in
writing in accordance herewith. Notice and communications shall be effective
when actually received by the addressee.

          19.8  Survival. Sections 9 ("Consulting and Severance Package Upon
Termination of Employment")(as applicable), 10 ("Definitions"), 13
("Confidentiality and Proprietary Rights"), 14 ("Nonsolicitation"), 15
("Nondisparagement"), 16 ("Injunctive Relief"), 18 ("Certain Additional
Payments By Company"), 19 ("General Provisions") and 21 ("Entire Agreement") of
this Agreement shall survive Executive's employment by Company.

     20.  Counterparts. This Agreement may be executed in counterparts. The
execution of a signature page of this Agreement shall constitute the execution
of the Agreement, and the Agreement shall be binding on each party upon the
date of signature, if each party executes such counterpart.

     21.  Entire Agreement. This Agreement, including Exhibits A, B, C and the
Confidentiality Agreements attached at Exhibit D, all of which are incorporated
herein by

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<PAGE>
reference, and Company's stock option plans and related option documents,
constitute the entire agreement between the parties relating to this subject
matter hereof and supersede all prior or simultaneous representations,
discussions, negotiations, and agreements, whether written or oral, including
but not limited to the Change-in-Control Agreement, which is hereby superseded
in its entirety. This Agreement may be amended or modified only with the written
consent of Executive and an authorized member of the Board of Directors of
Company. No oral waiver, amendment or modification will be effective under any
circumstances whatsoever.

THE PARTIES TO THIS AGREEMENT HAVE READ THE FOREGOING AGREEMENT AND FULLY
UNDERSTAND EACH AND EVERY PROVISION CONTAINED HEREIN. WHEREFORE, THE PARTIES
HAVE EXECUTED THIS AGREEMENT ON THE DATES SHOWN BELOW.



Dated:    1/29/03                                /s/ James R. Glynn
       -----------------                 -----------------------------------
                                                    JAMES R. GLYNN


Dated:    1/29/03                        By:     /s/ Lewis J. Runchey
       -----------------                 -----------------------------------
                                             INVITROGEN CORPORATION
                                             Lewis J. Runchey
                                             Vice President, Human Resources

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