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                                                                   EXHIBIT 10.25

                                THERASENSE, INC.

                          CHANGE OF CONTROL AGREEMENT

     This Change of Control Agreement (the "Agreement") is made and entered into
effective as of ___________, 2001 (the "Effective Date"), by and between
_____________________ (the "Employee") and TheraSense, Inc., a Delaware
corporation (the "Company").  Certain capitalized terms used in this Agreement
are defined in Section 1 below.

                                R E C I T A L S
                                ---------------


     A.  It is expected that the Company from time to time will consider the
possibility of a Change of Control. The Board of Directors of the Company
(the "Board") recognizes that such consideration can be a distraction to the
Employee and can cause the Employee to consider alternative employment
opportunities.

     B.  The Board believes that it is in the best interests of the Company and
its stockholders to provide the Employee with an incentive to continue his
employment and to maximize the value of the Company upon a Change of Control for
the benefit of its stockholders.

     C.  In order to provide the Employee with enhanced financial security and
sufficient encouragement to remain with the Company notwithstanding the
possibility of a Change of Control, the Board believes that it is imperative to
provide the Employee with certain benefits upon a Change of Control and upon the
Employee's termination of employment following a Change of Control.

                                   AGREEMENT
                                   ---------

     In consideration of the mutual covenants herein contained and the continued
employment of Employee by the Company, the parties agree as follows:

  1.  Definition of Terms.  The following terms referred to in this Agreement
      -------------------
shall have the following meanings:

        (a)  Cause.  "Cause" shall mean (i) any act of personal dishonesty taken
             -----
by the Employee in connection with his responsibilities as an employee which is
intended to result in substantial personal enrichment of the Employee, (ii)
Employee's conviction of a felony which the Board reasonably believes has had or
will have a material detrimental effect on the Company's reputation or business,
(iii) a willful act by the Employee which constitutes misconduct and is
injurious to the Company, or (iv) continued willful violations by the Employee
of the Employee's obligations to the Company after there has been delivered to
the Employee a written demand for performance from the Company which describes
the basis for the Company's belief that the Employee has not substantially
performed his duties.

        (b)  Change of Control.  "Change of Control" shall mean the occurrence
             -----------------
of any of the following events:
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                (i) the approval by stockholders of the Company of a merger or
     consolidation of the Company with any other corporation, other than a
     merger or consolidation which would result in the voting securities of the
     Company outstanding immediately prior thereto continuing to represent
     (either by remaining outstanding or by being converted into voting
     securities of the surviving entity) more than fifty percent (50%) of the
     total voting power represented by the voting securities of the Company or
     such surviving entity outstanding immediately after such merger or
     consolidation;

        (ii) the approval by the stockholders of the Company of a plan of
     complete liquidation of the Company or an agreement for the sale or
     disposition by the Company of all or substantially all of the Company's
     assets;

        (iii) any "person" (as such term is used in Sections 13(d) and 14(d) of
     the Securities Exchange Act of 1934, as amended) becoming the "beneficial
     owner" (as defined in Rule 13d-3 under said Act), directly or indirectly,
     of securities of the Company representing 50% or more of the total voting
     power represented by the Company's then outstanding voting securities; or

        (iv) a change in the composition of the Board, as a result of which
     fewer than a majority of the directors are Incumbent Directors. "Incumbent
     Directors" shall mean directors who either (A) are directors of the Company
     as of the date hereof, or (B) are elected, or nominated for election, to
     the Board with the affirmative votes of at least a majority of those
     directors whose election or nomination was not in connection with any
     transactions described in subsections (i), (ii), or (iii) or in connection
     with an actual or threatened proxy contest relating to the election of
     directors of the Company.

        (c)  Involuntary Termination.  "Involuntary Termination" shall mean (i)
             -----------------------
without the Employee's express written consent, a significant reduction of the
Employee's duties, position or responsibilities relative to the Employee's
duties, position or responsibilities in effect immediately prior to such
reduction, or the removal of the Employee from such position, duties and
responsibilities; provided, however, that a reduction in duties, position or
responsibilities solely by virtue of the Company being acquired and made part of
a larger entity (as, for example, when the Chief Financial Officer of the
Company remains as such following a Change of Control but is not made the Chief
Financial Officer of the acquiring corporation) shall not constitute an
"Involuntary Termination;" (ii) without the Employee's express written consent,
a substantial reduction, without good business reasons, of the facilities and
perquisites (including office space and location) available to the Employee
immediately prior to such reduction; (iii) without the Employee's express
written consent, a reduction by the Company of the Employee's base salary as in
effect immediately prior to such reduction; (iv) without the Employee's express
written consent, a material reduction by the Company in the kind or level of
employee benefits to which the Employee is entitled immediately prior to such
reduction with the result that the Employee's overall benefits package is
significantly reduced; (v) without the Employee's express written consent, the
relocation of the Employee to a facility or a location more than fifty (50)
miles from his current location; (vi) any purported termination of the Employee
by the Company which is not effected for Cause; or (vii) the failure of the
Company to obtain the assumption of this Agreement by any successors
contemplated in Section 6 below.

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        (d)  Options.  "Options" shall mean all options to purchase shares of
             -------
the Company's Common Stock previously granted by Company to Employee under the
Company's 1997 Stock Plan or options to purchase shares of the Company's Common
Stock that are granted by Company to Employee after the date hereof and prior to
the date of a Change of Control, if any, under the Company's equity incentive
plans as may be in effect from time to time.

        (e) Purchased Stock.  "Purchased Stock" shall mean all shares of the
            ---------------
Company's Common Stock purchased by Employee from the Company (whether purchased
prior to or after the date hereof) prior to the date of a Change of Control that
is subject to a right of repurchase in favor of the Company (or its successor),
which right lapses over time.

        (f) Termination Date.  "Termination Date" shall mean the effective
            ----------------
date of any notice of termination delivered by one party to the other
hereunder.

  2.  Term of Agreement.  This Agreement shall terminate upon the date that all
      -----------------
obligations of the parties hereto under this Agreement have been satisfied or,
if earlier, on the date, prior to a Change of Control, Employee is no longer
employed by the Company.

  3.  At-Will Employment.  The Company and the Employee acknowledge that the
      ------------------
Employee's employment is and shall continue to be at-will, as defined under
applicable law.  If the Employee's employment terminates for any reason, the
Employee shall not be entitled to any payments, benefits, damages, awards or
compensation other than as provided by this Agreement, or as may otherwise be
established under the Company's then existing employee benefit plans or policies
at the time of termination.

  4.  Accelerated Vesting Benefits.
      ----------------------------

        (a)  Upon a Change of Control.  Upon a Change of Control, seventy-five
             ------------------------
percent (75%) of the then unvested Options granted by the Company to the
Employee prior to the Change of Control shall become fully vested and
exercisable as of the effective date of the Change of Control and all Purchased
Stock that was purchased prior to the Change of Control shall have such right of
repurchase lapse with respect to seventy-five percent (75%) of the then unvested
shares of Purchased Stock as of the effective date of the Change of Control;

        (b)  Termination Following A Change of Control.  If the Employee's
             -----------------------------------------
employment with the Company terminates as a result of an Involuntary Termination
at any time after a Change of Control, the remaining unvested Options granted by
the Company to the Employee prior to the Change of Control shall become fully
vested and exercisable effective as of the Termination Date and all Purchased
Stock that was purchased prior to the Change of Control shall have such right of
repurchase lapse with respect to the remaining unvested shares of Purchased
Stock effective as of the Termination Date.

        (c)  Termination Apart from a Change of Control.  If the Employee's
             ------------------------------------------
employment with the Company terminates other than as a result of an Involuntary
Termination following a Change of Control, then the Employee shall not be
entitled to receive the benefits hereunder.

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  5. Limitation on Payments.  In the event that the accelerated vesting benefits
     ----------------------
provided for in this Agreement (i) constitute "parachute payments" within the
meaning of Section 280G of the Code, and (ii) would be subject to the excise tax
imposed by Section 4999 of the Code (the "Excise Tax"), then Employee's benefits
under this Agreement shall be either

        (a)  delivered in full, or

        (b) delivered as to such lesser extent which would result in no portion
of such benefits being subject to the Excise Tax,

     whichever of the foregoing amounts, taking into account the applicable
federal, state and local income taxes and the Excise Tax, results in the receipt
by Employee on an after-tax basis, of the greatest amount of benefits,
notwithstanding that all or some portion of such benefits may be taxable under
Section 4999 of the Code.

     Unless the Company and the Employee otherwise agree in writing, any
determination required under this Section shall be made in writing by the
Company's independent public accountants (the "Accountants"), whose
determination shall be conclusive and binding upon the Employee and the Company
for all purposes.  For purposes of making the calculations required by this
Section, the Accountants may make reasonable assumptions and approximations
concerning applicable taxes and may rely on reasonable, good faith
interpretations concerning the application of Section 280G and 4999 of the Code.
The Company and the Employee shall furnish to the Accountants such information
and documents as the Accountants may reasonably request in order to make a
determination under this Section.  The Company shall bear all costs the
Accountants may reasonably incur in connection with any calculations
contemplated by this Section.

  6.  Successors.
      ----------

        (a)  Company's Successors.  Any successor to the Company (whether
             --------------------
direct or indirect and whether by purchase, lease, merger, consolidation,
liquidation or otherwise) to all or substantially all of the Company's business
and/or assets shall assume the Company's obligations under this Agreement and
agree expressly to perform the Company's obligations under this Agreement in the
same manner and to the same extent as the Company would be required to perform
such obligations in the absence of a succession. For all purposes under this
Agreement, the term "Company" shall include any successor to the Company's
business and/or assets which executes and delivers the assumption agreement
described in this subsection (a) or which becomes bound by the terms of this
Agreement by operation of law.

        (b)  Employee's Successors.    Without the written consent of the
             ---------------------
Company, Employee shall not assign or transfer this Agreement or any right or
obligation under this Agreement to any other person or entity. Notwithstanding
the foregoing, the terms of this Agreement and all rights of Employee hereunder
shall inure to the benefit of, and be enforceable by, Employee's personal or
legal representatives, executors, administrators, successors, heirs,
distributees, devisees and legatees.

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    7.  Notices.
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        (a)  General.  Notices and all other communications contemplated by this
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Agreement shall be in writing and shall be deemed to have been duly given when
personally delivered or when mailed by U.S. registered or certified mail, return
receipt requested and postage prepaid. In the case of the Employee, mailed
notices shall be addressed to him at the home address which he most recently
communicated to the Company in writing. In the case of the Company, mailed
notices shall be addressed to its corporate headquarters, and all notices shall
be directed to the attention of its Secretary.

        (b)  Notice of Termination.  Any termination by the Company for Cause
             ---------------------
or by the Employee as a result of a voluntary resignation or an Involuntary
Termination shall be communicated by a notice of termination to the other party
hereto given in accordance with this Section. Such notice shall indicate the
specific termination provision in this Agreement relied upon, shall set forth in
reasonable detail the facts and circumstances claimed to provide a basis for
termination under the provision so indicated, and shall specify the Termination
Date (which shall be not more than 30 days after the giving of such notice). The
failure by the Employee to include in the notice any fact or circumstance which
contributes to a showing of Involuntary Termination shall not waive any right of
the Employee hereunder or preclude the Employee from asserting such fact or
circumstance in enforcing his rights hereunder.

    8.  Arbitration.
        -----------

        (a) Any dispute or controversy arising out of, relating to, or in
connection with this Agreement, or the interpretation, validity, construction,
performance, breach, or termination thereof, shall be settled by binding
arbitration to be held in Alameda County in accordance with the National Rules
for the Resolution of Employment Disputes then in effect of the American
Arbitration Association (the "Rules"). The arbitrator may grant injunctions or
other relief in such dispute or controversy. The decision of the arbitrator
shall be final, conclusive and binding on the parties to the arbitration.
Judgment may be entered on the arbitrator's decision in any court having
jurisdiction.

        (b) The arbitrator(s) shall apply California law to the merits of any
dispute or claim, without reference to conflicts of law rules. The arbitration
proceedings shall be governed by federal arbitration law and by the Rules,
without reference to state arbitration law. Employee hereby consents to the
personal jurisdiction of the state and federal courts located in California for
any action or proceeding arising from or relating to this Agreement or relating
to any arbitration in which the parties are participants.

        (c) Employee understands that nothing in this Section modifies
Employee's at-will employment status. Either Employee or the Company can
terminate the employment relationship at any time, with or without Cause.

        (d) EMPLOYEE HAS READ AND UNDERSTANDS THIS SECTION, WHICH DISCUSSES
ARBITRATION. EMPLOYEE UNDERSTANDS THAT SUBMITTING ANY

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CLAIMS ARISING OUT OF, RELATING TO, OR IN CONNECTION WITH THIS AGREEMENT, OR
THE INTERPRETATION, VALIDITY, CONSTRUCTION, PERFORMANCE, BREACH OR TERMINATION
THEREOF TO BINDING ARBITRATION, CONSTITUTES A WAIVER OF EMPLOYEE'S RIGHT TO A
JURY TRIAL AND RELATES TO THE RESOLUTION OF ALL DISPUTES RELATING TO ALL ASPECTS
OF THE EMPLOYER/EMPLOYEE RELATIONSHIP, INCLUDING BUT NOT LIMITED TO, THE
FOLLOWING CLAIMS:

        (i)   ANY AND ALL CLAIMS FOR WRONGFUL DISCHARGE OF EMPLOYMENT; BREACH OF
     CONTRACT, BOTH EXPRESS AND IMPLIED; BREACH OF THE COVENANT OF GOOD FAITH
     AND FAIR DEALING, BOTH EXPRESS AND IMPLIED; NEGLIGENT OR INTENTIONAL
     INFLICTION OF EMOTIONAL DISTRESS; NEGLIGENT OR INTENTIONAL
     MISREPRESENTATION; NEGLIGENT OR INTENTIONAL INTERFERENCE WITH CONTRACT OR
     PROSPECTIVE ECONOMIC ADVANTAGE; AND DEFAMATION.

        (ii)  ANY AND ALL CLAIMS FOR VIOLATION OF ANY FEDERAL STATE OR MUNICIPAL
     STATUTE, INCLUDING, BUT NOT LIMITED TO, TITLE VII OF THE CIVIL RIGHTS ACT
     OF 1964, THE CIVIL RIGHTS ACT OF 1991, THE AGE DISCRIMINATION IN EMPLOYMENT
     ACT OF 1967, THE AMERICANS WITH DISABILITIES ACT OF 1990, THE FAIR LABOR
     STANDARDS ACT, THE CALIFORNIA FAIR EMPLOYMENT AND HOUSING ACT, AND LABOR
     CODE SECTION 201, et seq;

        (iii) ANY AND ALL CLAIMS ARISING OUT OF ANY OTHER LAWS AND REGULATIONS
     RELATING TO EMPLOYMENT OR EMPLOYMENT DISCRIMINATION.

    9.  Miscellaneous Provisions.
        ------------------------

        (a)  No Duty to Mitigate.  The Employee shall not be required to
             -------------------
mitigate the amount of any payment contemplated by this Agreement, nor shall any
such payment be reduced by any earnings that the Employee may receive from any
other source.

        (b)  Waiver.  No provision of this Agreement may be modified, waived or
             ------
discharged unless the modification, waiver or discharge is agreed to in writing
and signed by the Employee and by an authorized officer of the Company (other
than the Employee). No waiver by either party of any breach of, or of compliance
with, any condition or provision of this Agreement by the other party shall be
considered a waiver of any other condition or provision or of the same condition
or provision at another time.

        (c)  Integration; Conflict.  This Agreement and any outstanding stock
             ---------------------
option agreements and restricted stock purchase agreements between the Company
and Employee represent the entire agreement and understanding between the
parties as to the subject matter herein and supersede all prior or
contemporaneous agreements, whether written or oral, with respect to this
Agreement and any stock option agreement or restricted stock purchase agreement.
To the extent the terms and conditions of Section 1 or Section 4 of this
Agreement are different from or conflict with

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similar terms and conditions set forth in any outstanding stock option
agreements or restricted stock purchase agreements between the Company and
Employee, Section 1 and Section 4 of this Agreement shall govern.

        (d)  Choice of Law.  The validity, interpretation, construction and
             -------------
performance of this Agreement shall be governed by the internal substantive
laws, but not the conflicts of law rules, of the State of California.

        (e)  Severability.  The invalidity or unenforceability of any provision
             ------------
or provisions of this Agreement shall not affect the validity or enforceability
of any other provision hereof, which shall remain in full force and effect.

        (f)  Employment Taxes.  All payments made pursuant to this Agreement
             ----------------
shall be subject to withholding of applicable income and employment taxes.

        (g)  Counterparts.  This Agreement may be executed in counterparts,
             ------------
each of which shall be deemed an original, but all of which together will
constitute one and the same instrument.

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IN WITNESS WHEREOF, each of the parties has executed this Agreement, in the case
of the Company by its duly authorized officer, as of the day and year first
above written.


COMPANY:                                THERASENSE, INC.

                                        By:
                                           ----------------------------
                                        Title:
                                              -------------------------

EMPLOYEE:
                                        -------------------------------
                                        Signature


                                        -------------------------------
                                        Printed Name

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