Document:

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                                                                   Exhibit 10.15

                                  APBIOTECH INC

                         US EMPLOYEE STOCK PURCHASE PLAN

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                                    ARTICLE I
                                  Introduction

      Sec. 1.01 Statement of Purpose. The purpose of the APBiotech Inc US
Employee Stock Purchase Plan is to provide eligible employees of certain United
States subsidiaries of the Company, who wish to become shareholders, an
opportunity to purchase Stock in Company. The Board of Directors of the Company
believes that employee participation in stock ownership will be to the mutual
benefit of the employees and the Company.

      Sec. 1.02 Internal Revenue Code Considerations. The Plan is intended to
constitute an "employee stock purchase plan" within the meaning of section 423
of the Internal Revenue Code of 1986, as amended. The Plan will be approved by
the Company's shareholders within 12 months of the Plan being adopted by the
Board of Directors.

      Sec. 1.03 ERISA Considerations. The Plan is not intended and shall not be
construed as constituting an "employee benefit plan," within the meaning of
section 3(3) of the Employee Retirement Income Security Act of 1974, as amended.

                                   ARTICLE II
                                   Definitions

      Sec. 2.01 "Shares" means shares in the Company's Common Stock, $0.01 par
value.

      Sec. 2.02 "Board of Directors" means the board of directors of the Company
or a committee of the board of directors authorized to act on its behalf.

      Sec. 2.03 "Code" means the Internal Revenue Code of 1986, as amended, and
any successor statute of similar nature. References to specific sections of the
Code shall be taken to be references to corresponding sections of any successor
statute.

      Sec. 2.04 "Committee" means the committee appointed by the Board of
Directors to administer the Plan, as provided in Section 6.03 hereof, or any
delegate of that committee.

      Sec. 2.05 "Company" means APBiotech Inc.

      Sec. 2.06 "Effective Date" means January 1, 2001.

      Sec. 2.07 "Election Date" means each January 1 and July 1 or such other
dates as the Committee shall specify.

                  Sec. 2.08 "Eligible Employee" means each person employed as an
employee of an Employer who (a)(i) has been employed by an Employer for not less
than three (3) months and (ii) is customarily employed for more than twenty (20)
hours per week, and (b) is not

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deemed for purposes of section 423(b) (3) of the Code to own stock possessing
five percent or more of the total combined voting power or value of all classes
of stock of the Company or any Subsidiary.

      Sec. 2.09 "Employer" means each Subsidiary.

      Sec. 2.10 "Exchange Act" means the Securities Exchange Act of 1934, as
amended, and as the same may hereafter be amended.

      Sec. 2.11 "Market Value" means the last price for the Shares as reported
on NASDAQ for the date of reference. If there was no such price reported for the
date of reference, "Market Value" means the "Market Value" as of the date next
preceding the date of reference for which such price was reported.

      Sec. 2.12 "Participant" means each Eligible Employee who elects to
participate in the Plan.

      Sec. 2.13 "Plan" means the APBiotech Inc US Employee Stock Purchase Plan,
as the same is set forth herein and as the same may hereafter be amended.

      Sec. 2.14 "Purchase Agreement" means the instrument prescribed by the
Committee pursuant to which an Eligible Employee may enroll as a Participant and
subscribe for the purchase of Shares on the terms and conditions offered by the
Company. The Purchase Agreement also is intended to evidence the Company's offer
of an option to the Eligible Employee to purchase Shares on the terms and
conditions set forth therein and herein.

      Sec. 2.15 "Purchase Date" means June 30, 2001 and the last business day of
each Purchase Period ending thereafter.

      Sec. 2.16 "Purchase Period" means, beginning January 1, 2001, each
six-calendar month period or other period specified by the Committee during
which the Participant's stock purchase is funded through payroll deduction
accumulations.

      Sec. 2.17 "Subsidiary" means any present or future corporation (i) which
constitutes a "subsidiary corporation" of the Company as that term is defined in
section 424 of the Code, and (ii) is designated as a participating entity in the
Plan by the Committee. Unless the Committee specifically designates otherwise, a
subsidiary not incorporated and resident in the United States shall not be
considered a Subsidiary for purposes of the Plan, and employees of such a
subsidiary shall not be Eligible Employees.

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                                   ARTICLE III
                           Admission to Participation

      Sec. 3.01 Initial Participation. Any Eligible Employee may elect to
participate in the Plan and may become a Participant by executing and filing
with the Committee a Purchase Agreement at such time in advance of any
subsequent Election Date as the Committee shall prescribe. An Eligible
Employee's initial election to participate in the Plan may be made at any time
after he or she first becomes eligible to participate in the Plan and shall be
effective as of the next Election Date after the Eligible Employee submits in a
timely manner the necessary documentation to the Committee. After an Eligible
Employee has first become a Participant in the Plan, subsequent elections to
participate in the Plan shall be made pursuant to Section 3.03. A Participants'
Purchase Agreement shall remain in effect until modified or canceled in
accordance with the further terms of this Plan, as hereinafter set forth.

      Sec. 3.02 Discontinuance of Participation. A Participant may voluntarily
cease his or her participation in the Plan and stop payroll deductions at any
time by filing a notice of cessation of participation on such form and at such
time in advance of the effective date as the Committee shall prescribe.
Notwithstanding anything in the Plan to the contrary, if a Participant ceases to
be an Eligible Employee, his or her participation automatically shall cease and
no further purchase of shares shall be made for such Participant hereunder. In
either case, if a Participant ceases participation in the Plan before the end of
the then current Purchase Period, any amounts held for purchase of shares on
behalf of the Participant on the next subsequent Purchase Date shall be refunded
to the Participant.

      Sec. 3.03 Readmission to Participation. Any Eligible Employee who has
previously been a Participant, who has discontinued participation (whether by
cessation of eligibility or otherwise), and who wishes to be reinstated as a
Participant may again become a Participant by executing and filing with the
Committee a new Purchase Agreement. Reinstatement to Participant status shall be
effective as of any Election Date, provided the Participant files such new
Purchase Agreement with the Committee at such time in advance of such Election
Date as the Committee shall prescribe.

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                                   ARTICLE IV
                            Share Purchase and Resale

      Sec. 4.01 Reservation of Shares.

            (a) The maximum number of Shares which shall be issued under the
Plan (subject to adjustment in the capitalization of the Company in accordance
with Section 5.02 below) shall be 600,000 Shares.

            (b) Notwithstanding Section 4.01(a) above, the number of Shares that
may be purchased under the Plan in any calendar year, shall not exceed the
lesser of (i) the annual limit on such Shares, if any, established by the
Committee from time to time, or (ii) the number of Shares that would cause the
number of Shares in the Company which shall have been or may be issued in
pursuance of options or which have been or may issued otherwise than in
pursuance of options, under the Plan or under any other employees' share scheme
adopted by the Company, to exceed such number as represents 3% of the ordinary
share capital of the Company in issue at that time.

            (c) The limit at Section 4.01(b)(ii) above shall apply from the date
of adoption of the Plan by the Company until such date as determined by the
Committee, which shall not be before 1 June 2002 at the earliest.

            (d) Only those Shares which are capable of being issued before 1
June 2002 (or such later date as determined by the Directors pursuant to Section
4.01(c) above) on the exercise of any options or other awards will be relevant
for the purposes of calculating the limit in Section 4.01(b)(ii) above, and
Shares shall not be regarded as being capable of being issued by reason of any
provisions in the relevant employees' share schemes under which such options or
awards are granted allowing a person to exercise an option or award in
circumstances of leaving employment or a change of control of the Company.

      Sec. 4.02 Limitation on Shares Available.

            (a) Subject to the limitations of Section 4.04, the maximum number
of Shares that may be purchased for each Participant on a Purchase Date is the
lesser of (i) the number of whole and fractional Shares that can be purchased by
applying the full balance of the Participant's withheld funds to the purchase of
Shares at the Purchase Price, or (ii) the Participant's proportionate part of
the maximum number of Shares available under the Plan, as stated in Section
4.01.

            (b) Notwithstanding the foregoing, if any person entitled to
purchase Shares pursuant to any offering under the Plan would be deemed for
purposes of section 423(b)(3) of the Code to own stock (including any number of
Shares that such person would be entitled to purchase under the Plan) possessing
five percent or more of the total combined voting power or value of all classes
of stock of the Company, the maximum number of Shares that such person shall be
entitled to purchase pursuant to the Plan shall be reduced to that number which,
when added to the number of Shares of stock that such person is deemed to own
(excluding any number of Shares that such person would be entitled to purchase
under the Plan), is one less than

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such five percent. Any amounts withheld from a Participant's compensation that
cannot be applied to the purchase of Shares by reason of the foregoing
limitation or the limitation set forth in Section 4.02(a)(ii) shall be returned
to the Participant as soon as practicable.

      Sec. 4.03 Purchase Price of Shares. The Purchase Price per Share sold to
Participants pursuant to any offering hereunder shall be the lower of (i) 85% of
the Market Value per Share on the first day of the Purchase Period or (ii) 85%
of the Market Value per Share on the Purchase Date. Notwithstanding the
foregoing, the Board of Directors may determine that the Purchase Price for any
subsequent Purchase Period shall be the Market Value, or a percentage of the
Market Value on either of such dates or the lower of such dates, so long as such
percentage shall not be lower than 85% of such Market Value.

      Sec. 4.04 Exercise of Purchase Privilege.

            (a) Each Participant shall be granted an option to purchase Shares
as of the first day of each Purchase Period at the Purchase Price specified in
Section 4.03. The option shall continue in effect through the Purchase Date for
the Purchase Period. Subject to the provisions of Sections 3.02 and 4.02 above
and Sections 4.04(c) and 4.05 below, on each Purchase Date, the Participant
shall be automatically deemed to have exercised his or her option to purchase
Shares on the Purchase Date, unless he or she notifies the Committee, in such
manner and at such time in advance of the Purchase Date as the Committee shall
prescribe, of his or her desire not to make such purchase.

            (b) There shall be purchased for the Participant on such Purchase
Date at the Purchase Price for such Purchase Period the largest number of whole
and fractional Shares as can be purchased with the amounts withheld from the
Participant's compensation during the Purchase Period. Each such purchase shall
be deemed to have occurred on the Purchase Date occurring at the close of the
Purchase Period for which the purchase was made. Any amounts withheld from a
Participant's compensation during a Purchase Period that are not applied to
purchase Shares on the Purchase Date occurring at the close of that Purchase
Period shall be retained and applied to purchase Shares on the next subsequent
Purchase Date.

            (c) Notwithstanding the foregoing, a Participant may not purchase
Shares having an aggregate Market Value of more than $25,000, determined at the
beginning of each Purchase Period, for any calendar year in which one or more
such offerings are outstanding at any time, and a Participant may not purchase a
Share under any offering after the expiration of the Purchase Period for such
offering.

      Sec. 4.05 Payroll Deductions. Each Participant shall authorize payroll
deductions from his or her base pay for the purpose of funding the purchase of
Shares pursuant to his or her Purchase Agreement. In the Purchase Agreement,
each Participant shall authorize an after-tax payroll deduction from each
payment of his base pay during a Purchase Period, of an amount not less than $5
per paycheck and not more than a percentage of such Participant's base pay
determined by the Committee and communicated to Eligible Employees before the
beginning of that Purchase Period. A Participant may change the deduction to any
permissible level effective as of any Election Date. Such change shall be made
by the Participant's filing

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with the Committee a notice in such form and at such time in advance of the date
on which such change is to be effective as the Committee shall prescribe.

      Sec. 4.06 Payment for Shares. The Purchase Price for all Shares purchased
by a Participant under the Plan shall be paid out of the Participant's
authorized payroll deductions. All funds received or held by the Company under
the Plan are general assets of the Company, free of any trust or other
restriction, and may be used for any corporate purpose.

      Sec. 4.07 Share Ownership; Issuance of Certificates.

            (a) The Shares purchased by a Participant on a Purchase Date shall,
for all purposes, be deemed to have been issued or transferred at the close of
business on such Purchase Date. Prior to that time, none of the rights or
privileges of a shareholder of the Company shall inure to the Participant with
respect to such Shares. All the Shares purchased under the Plan shall be
delivered by the Company in a manner as determined by the Committee.

            (b) The Committee, in its sole discretion, may determine that the
Shares shall be delivered by the Company by (i) issuing and delivering to the
Participant a certificate for the number of Shares purchased by such Participant
on a Purchase Date or during a calendar year or other period determined by the
Committee, (ii) issuing and delivering a certificate or certificates for the
number of Shares purchased by all Participants on a Purchase Date or during a
calendar year or other period determined by the Committee to a firm which is a
member of the National Association of Securities Dealers, as selected by the
Committee from time to time, which shares shall be maintained by such firm in
separate brokerage accounts of each Participant, or (iii) issuing and delivering
a certificate or certificates for the number of Shares purchased by all
Participants on a Purchase Date or during the calendar year or other period
determined by the Committee to a bank or trust company or affiliate thereof, as
selected by the Committee from time to time, which shares may be held by such
bank or trust company or affiliate in "street name," but with separate accounts
maintained by such entity for each Participant reflecting such Participant's
interests in the Shares. Each certificate or account, as the case may be, shall
be in the name of the Participant.

            (c) In addition to any restrictions or limitations on the resale of
Shares purchased under the Plan set forth in Section 4.08 hereof or otherwise
hereunder, the Committee, in its sole discretion, may impose such restrictions
or limitations, as it shall determine, on the resale of Shares, the issuance of
individual stock certificates or withdrawal from any shareholder accounts
established for a Participant pursuant to the terms hereof.

            (d) Any dividends payable with respect to whole or fractional Shares
credited to a shareholder account of a Participant established pursuant to
Section 4.07(b) hereof will be reinvested in Shares and credited to such
Participant's account. Such reinvestment shall be made based on the Market Value
of the Shares on the date of the reinvestment, with no discount from Market
Value.

      Sec. 4.08 Withdrawal of Shares or Resale of Shares

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            (a) A Participant may (i) sell any Shares purchased hereunder by
requesting the sale of those Shares at any time in such form and at such time as
the Committee shall prescribe, or (ii) withdraw his or her Shares from any
shareholder account established pursuant to Section 4.07(b) hereof by requesting
the withdrawal of those Shares in such form and at such time as the Committee
shall prescribe, but not earlier than the second anniversary of the first day of
the Purchase Period for which options to purchase such Shares were granted.

            (b) If a Participant is to receive a withdrawal of Shares, the
withdrawal shall be paid in whole Shares, with fractional Shares paid in cash.

                                    ARTICLE V
                               Special Adjustments

      Sec. 5.01 Shares Unavailable. If, on any Purchase Date, the aggregate
funds available for the purchase of Shares would purchase a number of Shares in
excess of the number of shares then available for purchase under the Plan, the
following events shall occur:

            (a) The number of Shares that would otherwise be purchased by each
      Participant shall be proportionately reduced on the Purchase Date in order
      to eliminate such excess; and

            (b) The Plan shall automatically terminate immediately after the
      Purchase Date as of which the supply of available Shares is exhausted.

      Sec. 5.02 Anti-Dilution Provisions. The aggregate number of Shares
reserved for purchase under the Plan, as hereinabove provided, and the
calculation of the Purchase Price per Share may be appropriately adjusted to
reflect any increase or decrease in the number of issued Shares resulting from a
subdivision or consolidation of Shares or other capital adjustment, or the
payment of a stock dividend, or other increase or decrease in such Shares, if
effected without receipt of consideration by the Company. Any such adjustment
shall be made by the Committee acting with the consent of, and subject to the
approval of, the Board of Directors.

      Sec. 5.03 Effect of Certain Transactions. Subject to any required action
by the shareholders, if the Company shall be the surviving or resulting
corporation in any merger or consolidation, any offering hereunder shall pertain
to and apply to the Shares of the Company. In the event of a merger or
consolidation in which the Company is not the surviving or resulting
corporation, the Purchase Date for the Purchase Period during which such
transaction shall occur shall be the last business day preceding the closing
date for such transaction. In the event of a dissolution or liquidation of the
Company, the Plan and any offering hereunder shall terminate upon the effective
date of such dissolution, liquidation, merger or consolidation, and the balance
of any amounts withheld from the Participant's compensation, which had not by
such time been applied to the purchase of Shares shall be returned to the
Participant.

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                                   ARTICLE VI
                                 Miscellaneous.

      Sec. 6.01 Non-Alienation. The right to purchase Shares under the Plan is
personal to the Participant, is exercisable only by the Participant during the
Participant's lifetime except as hereinafter set forth, and may not be assigned
or otherwise transferred by the Participant. Notwithstanding the foregoing,
there shall be delivered to the executor, administrator or other personal
representative of a deceased Participant such Shares and such residual amounts
as may remain to the Participant's credit from amounts withheld from the
Participant's compensation as of the Purchase Date occurring at the close of the
period in which the Participant's death occurs, including Shares purchased as of
that date or prior thereto with moneys withheld from the Participant's
compensation.

      Sec. 6.02 Administrative Costs. The Company shall pay all Company related
administrative expenses, including stamp duty, associated with the operation of
the Plan.

      Sec. 6.03 The Committee. The Board of Directors shall appoint a Committee,
which shall have the authority and power to administer the Plan and to make,
adopt, construe, and enforce rules and regulations not inconsistent with the
provisions of the Plan. The Committee shall adopt and prescribe the contents of
all forms required in connection with the administration of the Plan, including,
but not limited to, the Purchase Agreement, payroll withholding authorizations,
withdrawal documents, and all other notices required hereunder. The Committee
shall have the fullest discretion permissible under law in the discharge of its
duties. The Committee's interpretations and decisions in respect of the Plan,
the rules and regulations pursuant to which it is operated, and the rights of
Participants hereunder shall be final and conclusive.

                  Sec. 6.04 Withholding of Taxes. All acquisitions of Shares
under the Plan shall be subject to applicable federal, state and local tax
withholding requirements if the Internal Revenue Service or other taxing
authority requires such withholding. The Company may require that Participants
pay to the Company (or make other arrangements satisfactory to the Company for
the payment of) the amount of any federal, state or local taxes that the Company
is required to withhold with respect to the purchase of Shares or the sale of
Shares acquired under the Plan, or the Company may deduct from the Participants
wages or other compensation the amount of any withholding taxes dues with
respect to the purchase of Shares or the sale of Shares acquired under the Plan.

      Sec. 6.05 Amendment of the Plan. The Board of Directors (or its delegate)
may amend or terminate the Plan at any time; provided, however, that the Board
of Directors (or its delegate)

            (a) shall not amend the Plan without stockholder approval if such
      approval is required by section 423 of the Code, and

            (b) shall not amend provisions relating to eligibility, limits on
      the purchase or availability of Shares, or other material Participant
      entitlements, where such amendments would be to the advantage of
      Participants, without prior stockholder approval

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      (provided that this requirement to obtain stockholder approval will not
      apply to any minor amendment to benefit the administration of the Plan, to
      take account of a change in legislation or to obtain or maintain
      favourable tax, exchange control, or regulatory treatment for Participants
      or the Company or any Subsidiary).

      Sec. 6.06 Expiration and Termination of the Plan. The Plan shall continue
in effect for 10 years from the date the Plan is approved by stockholders,
unless terminated prior thereto pursuant to the provisions of the Plan or
pursuant to action by the Board of Directors, which shall have the right to
terminate the Plan at any time without prior notice to any Participant and
without liability to any Participant. Upon the expiration or termination of the
Plan, the balance, if any, then standing to the credit of each Participant from
amounts withheld from the Participant's compensation which had not, by such
time, been applied to the purchase of Shares shall be refunded to the
Participant.

      Sec. 6.07 Repurchase of Shares. The Company shall not be required to
purchase or repurchase from any Participant any of the Shares that the
Participant acquired under the Plan.

      Sec. 6.08 Notice. A Purchase Agreement and any notice that a Participant
files pursuant to the Plan shall be on the form prescribed by the Committee and
shall be effective only when received by the Committee. Delivery of such forms
may be made by hand or by certified mail, sent postage prepaid. Forms shall be
addressed to Director of Compensation, Amersham Pharmacia Biotech, Inc., 80
Centennial Avenue, P. O. Box 1327, Piscataway, N.J. 08855. Delivery by any other
mechanism shall be deemed effective at the option and discretion of the
Committee.

      Sec. 6.09 Government Regulation. The Company's obligation to sell and to
deliver the Shares under the Plan is at all times subject to all approvals of
any governmental authority required in connection with the authorization,
issuance, sale or delivery of such Shares.

      Sec. 6.10 Headings, Captions, Gender. The headings and captions herein are
for convenience of reference only and shall not be considered as part of the
text. The masculine shall include the feminine, and vice versa.

      Sec. 6.11 Severability of Provisions, Prevailing Law. The provisions of
the Plan shall be deemed severable. In the event any such provision is
determined to be unlawful or unenforceable by a court of competent jurisdiction
or by reason of a change in an applicable statute, the Plan shall continue to
exist as though such provision had never been included therein (or, in the case
of a change in an applicable statute, had been deleted as of the date of such
change). The Plan shall be governed by the laws of the State of New Jersey to
the extent such laws are not in conflict with, or superseded by, federal law.

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                                                                   EXHIBIT 10.16

                                  RULES OF THE

                                  APBIOTECH INC

                       SAVINGS RELATED SHARE OPTION SCHEME

                                    New Bridge Street Consultants
                                    20 Little Britain
                                    London  EC1A  7DH
                                    Inland Revenue Reference: SRS 2530/ELW
                                    Date adopted: February 16, 2001
                                    Ref: N\1021\ARUNDEL\SRSOS JUN2000 v5

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                                    CONTENTS

                                                                          PAGE

1.   DEFINITIONS.............................................................1

2.   OFFERS OF OPTIONS.......................................................4

3.   OFFER AND APPLICATION...................................................4

4.   GRANT OF OPTIONS........................................................5

5.   LIMITATIONS.............................................................6

6.   EXERCISE OF OPTIONS.....................................................6

7.   RIGHTS OF EXERCISE AND LAPSE OF OPTIONS.................................7

8.   EXERCISE OF OPTIONS.....................................................9

9.   VARIATIONS.............................................................11

10.  ADMINISTRATION.........................................................12

11.  GENERAL................................................................12

12.  ALTERATIONS TO THIS SCHEME.............................................12

13.  GOVERNING LAW..........................................................13

<PAGE>   3

1.      DEFINITIONS

1.1     In this Scheme, except where inconsistent with the subject or context,
        words or expressions defined in or bearing a specific meaning for the
        purposes of Schedule 9 of the Taxes Act (or any statutory modification
        or re-enactment thereof - the "Statutory Provisions") or a relevant
        provision thereof shall bear the same meaning; and the words and
        expressions set out below shall bear the following respective meanings,
        namely:

        ACQUIRING COMPANY:   Any company which obtains control or becomes bound
                             or entitled to acquire Shares in accordance with
                             Rule 7.7;

        APPLICATION DATE:    In relation to any Offer, the date specified by
                             the Directors as the last day for receipt of
                             applications which shall be no less than 14 days
                             and no more than 21 days;

        AUDITORS:            The auditors for the time being of the Company;

        COMPANY:             APBiotech  Inc or in the event of another company
                             gaining control of APBiotech  Inc, and only in
                             relation to new rights granted in accordance with
                             Rule 7.7, the acquiring company (but so as not to
                             extend to the term the "Company" included in the
                             definitions of the "Group" or "Subsidiary");

        DIRECTORS:           The Board of Directors of the Company or a duly
                             authorised committee thereof;

        EMPLOYEE:            An employee (including a director holding a
                             salaried employment or office) of any member of
                             the Group;

        GROUP:               The Company and any Subsidiary for the time being
                             designated by the Directors as a member of the
                             Group for the purposes of this Scheme or, where the
                             context permits, any one or more of them;

        MARKET VALUE:        The market value (within the meaning of Part VIII
                             of the Taxation of Chargeable Gains Act 1992) of
                             shares of that class, as agreed in advance for the
                             purposes of this Scheme with the Shares Valuation
                             Division of the Inland Revenue;

        NEW OPTION:          An option granted pursuant to Rule 7.7;

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        OFFER:                A general invitation to Qualifying Employees to
                              apply for an Option;

        OFFER DATE:           The date on which an Offer is made;

        OLD OPTION:           Option released pursuant to Rule 7.8;

        OPTION:               A right to acquire Shares granted to a Qualifying
                              Employee in pursuance of this Scheme and for the
                              time being subsisting;

        OPTION EXERCISE DATE: The date when an Option is effectively exercised
                              upon compliance with the provisions of Rule 8.1;

        OPTION HOLDER:        A person holding an Option or, where the context
                              requires or permits, his legal personal
                              representatives (but not his trustee in
                              bankruptcy);

        OPTION PRICE:         In relation to any Option:

                              (i)  as at the Offer Date, such price per Share as
                                   may have been determined by the Directors
                                   being an amount not less than whichever shall
                                   be the greater of the Market Value minus the
                                   lesser of:

                                   (a) the discount allowable under the
                                       applicable legislation; and

                                   (b) 20 per cent, thereof and, if the
                                       Shares are to be subscribed, the nominal
                                       amount of an Share; and

                              (ii) as at any other date, such price as adjusted
                                   pursuant to this Scheme;

        ORIGINAL SHAREHOLDER: means Nycomed  Amersham plc (or a subsidiary  of
                              Nycomed  Amersham plc) or Pharmacia Corp (or any
                              subsidiary of Pharmacia Corp);

        QUALIFYING EMPLOYEE:  As at such date as the Directors  may  prescribe
                              (being as near as conveniently practicable to the
                              related  Offer  Date), any Employee who either:

                              (i)  (a)  is chargeable to tax in respect of his
                                        office or employment under

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<PAGE>   5

                                        Case 1 of Schedule E of the Taxes Act;
                                        and

                                   (b)  has such qualifying period (if any) of
                                        continuous employment (being a period
                                        commencing not earlier than five years
                                        prior to the Date of Grant) as the
                                        Directors may determine; or

                              (ii) is nominated by the Directors as a
                                   Qualifying Employee.

        RELATED SAVINGS CONTRACT:  In relation to any Option, a Savings Contract
                                   in respect whereof a duly signed proposal is
                                   delivered to the Company in accordance with
                                   Rule 3.2.2;

        RELEVANT ANNIVERSARY:      The date on which any bonus becomes payable
                                   under the terms of a Related Savings
                                   Contract;

        RELEVANT EVENT:            Any variation in the share capital of the
                                   Company arising from any reduction of capital
                                   or subdivision or consolidation of capital or
                                   issue of shares by way of capitalisation of
                                   profits or reserves or by way of rights;

        REPAYMENT AMOUNT:          In relation to any Option Holder, that part
                                   of the amount payable to him upon the
                                   termination of a Related Savings Contract as
                                   is equal to the aggregate amount of all
                                   contributions made by him thereunder (and so
                                   that there shall be disregarded any
                                   contributions whose due date would have
                                   fallen more than one month after such
                                   termination) and any bonus, maximum bonus or
                                   payment of interest received;

        SAVINGS CONTRACT:          A contract under a certified contractual
                                   savings scheme approved by the Board of
                                   Inland Revenue for the purposes of the
                                   Statutory  Provisions and within the meaning
                                   of S326 of the Taxes Act;

        SCHEME:                    This scheme in its present form or as from
                                   time to time altered in accordance with the
                                   provisions hereof;

        SHARES:                    Shares in the Company's common stock,
                                   US$ 0.01- par value which satisfy the
                                   conditions

                                      - 3 -
<PAGE>   6

                                   specified in Paragraphs 10 to 14 (inclusive)
                                   of Schedule 9 of the Taxes Act;

        SPECIFIED AGE:             Age 65;

        SUBSIDIARY:                Any company which is for the time being under
                                   the control of the Company;

        TAXES ACT:                 The Income and Corporation Taxes Act 1988.

        TRUSTEES:                  The trustee or trustees for the time being of
                                   any employee benefit trust established for
                                   the benefit of beneficiaries including all or
                                   substantially all of the Employees, including
                                   a qualifying employee share ownership trust
                                   within the meaning of the Finance Act 1989,
                                   which has confirmed to the Company that it
                                   will comply with the Scheme.

2.      OFFERS OF OPTIONS.

2.1     Subject to the restrictions hereinafter contained, the Directors may
        from time to time make an Offer to all Qualifying Employees. Each Offer
        may be limited to such maximum number of Shares over which Options may
        be granted as shall be specified by the Directors.

2.2     An offer shall only be made at such times as may be permitted by
        applicable securities laws and no offer shall be made until approval of
        the Scheme by the Board of the Inland Revenue pursuant to Schedule 9 of
        the Taxes Act.

3.      OFFER AND APPLICATION.

3.1     The directors may make an Offer by whatever means (whether by notice,
        advertisement, circular or otherwise and whether addressed to Qualifying
        Employees generally or individually) they think fit. Each Offer shall
        constitute an invitation to each Qualifying Employee to apply on or
        before the related Application Date for the grant of an Option over such
        number of Shares as may be appropriate pursuant to the provisions of
        Rule 4.

3.2     Each application for an Option must:

        3.2.1   be made on the prescribed application form in accordance with
                any related instructions

        3.2.2   be accompanied by a duly signed proposal for a Savings Contract
                which will oblige the Qualifying Employee concerned to make
                monthly contributions of an aggregate amount of not more than
                that specified in the related Offer;.

        3.2.3   be accompanied by an authority for the contributions to be
                payable thereunder to be deducted from his remuneration;

        3.2.4   specify whether the Repayment Amount is to include the bonus
                under the Related Savings Contract

                                      - 4 -
<PAGE>   7

4.      GRANT OF OPTIONS.

4.1     As soon as practicable after each Application Date (but not later than
        30 days or, in the event of the Company having to scale down
        applications pursuant to Rule 4.2, 42 days after the first date by
        reference to which the Market Value was established for the purpose of
        the related Offer) each Qualifying Employee who has applied for an
        Option pursuant to the related Offer (provided that he is then an
        Employee and that his application has not been withdrawn) shall be
        granted a non-transferable Option at the applicable Option Price and for
        the applicable duration over the least of:

        4.1.1   the number of Shares which are the subject of such application;

        4.1.2   any lesser number in respect of which such application is
                accepted in order to ensure, following any scaling down under
                Rule 4.2, that the total number of Shares over which options are
                granted pursuant to the related Offer does not exceed any number
                specified in that Offer;

        4.1.3   the number of Shares over which an Option may be granted under
                Rule 5.

4.2     If following any Offer, the Company receives valid applications which
        would result in the total number of Shares over which Options are
        granted pursuant to that Offer exceeding any maximum number specified in
        that Offer pursuant to Rule 2.1 or any maximum specified in Rule 5.4,
        the Directors shall scale down applications by taking at their absolute
        discretion - any one or more of the following methods steps until the
        number of Shares available equals or exceeds the number of Shares
        applied for:

        4.2.1   by selecting applications by lot, each based on the proposed
                monthly amounts specified in the agreed invitations reduced pro
                rata to the excess over (pound)10; or

        4.2.2   by treating each election for a bonus as an election for no
                bonus; or

        4.2.3   by reducing the proposed monthly amounts specified in the
                invitation pro rata to the excess over(pound)10 to the extent
                necessary.

        If the number of Shares available is insufficient to enable an Option
        based on monthly contributions of the minimum monthly amount specified
        in the Offer to be granted to each Qualifying Employee making a valid
        application, the Directors may, as an alternative to the above,
        determine in their absolute discretion that no Options shall be granted.

        If the Directors so determine, the provisions in Rule 4.2.1, 4.2.2 and
        4.2.3 may be modified or applied in any manner as may be agreed in
        advance with the Inland Revenue.

4.3     No payment shall be required for the grant of any Option. Each Option
        shall be granted by means of a certificate under the autographic or
        facsimile signatures of a Director and the Secretary or executed in such
        other manner as appropriate or as may be required from time to time by
        legislation or by the Directors.

                                     - 5 -
<PAGE>   8
5.      LIMITATIONS

5.1     No Option shall be granted to any Qualifying Employee pursuant to any
        Offer if the monthly amount agreed to be saved in respect of that Option
        under the Related Savings Contract:

        5.1.1   would be less than the minimum amount specified in the Offer;
                and

        5.1.2   would exceed the maximum monthly contribution as may be
                permitted pursuant to paragraph 24 of Schedule 9 to the Taxes
                Act (or such lower monthly maximum contribution as may be
                determined from time to time by the Directors) when taken
                together with any monthly contributions he makes under any other
                Savings Contract related to options.

5.2     No person shall be eligible to receive or exercise an Option at any time
        when he has (or had within the preceding 12 months) a material interest
        within the meaning of Section 187(3)(a) of the Taxes Act in (if it is at
        that time a close company) the Company or in a close company which has
        control of the Company or is a member of a consortium which owns the
        Company.

5.3     No Option shall be granted more than 10 years after the date of adoption
        of the Scheme.

5.4     5.4.1  Subject to Rules 5.4.2 and 5.4.3 below, no Options shall be
               granted under the Scheme which would, at the time they are
               granted, cause the number of Shares which may be issued in
               pursuance of Options granted under the Scheme, or in pursuance
               of options or other awards made under any other employees' share
               scheme of the Company, to exceed such number as represents 3% of
               the ordinary share capital of the Company from time to time.

        5.4.2  The limit at Rule 5.4.1 above shall apply from the date of
               adoption of the Scheme by the Company until such date as
               determined by the Directors, which shall not be before 1 June
               2002 at the earliest.

        5.4.3  Only those Shares which are capable of being issued before 1
               June 2002 (or such later date as determined by the Directors
               pursuant to Rule 5.4.2 above) on the exercise of any options
               or other awards will be relevant for the purposes of calculating
               the limit in rule 5.4.1 above, and Shares shall not be regarded
               as being capable of being issued by reason of any provisions in
               the relevant employees' share schemes under which such options or
               awards are granted allowing a person to exercise an option or
               award in circumstances of leaving employment or a change of
               control of the Company.

6.      EXERCISE OF OPTIONS

6.1     Save as hereinafter provided, an Option may be exercised only during the
        period of six months commencing on the Relevant Anniversary of the
        Related Savings Contract; and (notwithstanding any other provision of
        this Scheme);

        6.1.1   it may only be exercised after such period pursuant to Rule 7.1;
                and

        6.1.2   it may only (save as provided in Rules 7.1, 7.3, 7.4 and 7.8)
                be exercised by a person who is an Employee at the date of
                exercise.

                                      - 6 -
<PAGE>   9

6.2     Save as provided in Rule 7, in the event of an Option Holder ceasing to
        be an Employee all his Options shall thereupon cease and determine;
        provided that, for the purposes of this provision and of Rules 7.3, 7.4
        and 7.8 no person shall be treated as ceasing to be an Employee until he
        ceases to be an employee or a director holding a salaried employment or
        office of the Company or of any company which is controlled by, or is an
        associated company of, the Company.

6.3     If, before the earliest time when, in accordance with the provisions of
        the Scheme, an Option Holder may exercise an Option he gives (or is
        deemed to have given) notice that he intends to stop paying
        contributions under a Related Savings Contract, such Option shall
        thereupon cease and determine.

6.4     If an Option Holder is adjudicated bankrupt, any Options held by him
        shall automatically cease and determine.

7.      RIGHTS OF EXERCISE AND LAPSE OF OPTIONS.

7.1     If an Option Holder dies whilst any Option remains in whole or in part
        available for future exercise by him, such Option may be exercised in
        whole or in part at any time during the period of 12 months from the
        earlier of

        7.1.1   the date of his death; and.

        7.1.2   the Relevant Anniversary of the Related Savings Contract

        To the extent that any Option so exercisable is not exercised within
        such period, it shall thereupon cease and determine.

7.2     If an Option Holder remains an Employee  after he has reached the
        Specified  Age, he may exercise an Option in whole or in part within
        six months after attaining such age.

7.3     If an Option Holder ceases to be an Employee by reason of:

        7.3.1   injury or disability (evidenced to the satisfaction of the
                Directors); or

        7.3.2   redundancy; or.

        7.3.3   retirement on reaching the Specified Age or any other age at
                which he is bound to retire in accordance with the terms of his
                contract of employment; or

        7.3.4   his employing company ceasing to be under the Control of the
                Company or the business or part of a business in which he is
                employed being transferred to a person who is neither an
                Associated Company nor a company of which the Company has
                Control;

        he may exercise any Option in whole or in part within six months
        thereafter. To the extent that any Option so exercisable is not
        exercised within such period, it shall thereupon cease and determine.

7.4     If, after the third anniversary of the grant of an Option, an Option
        Holder ceases to be an Employee by reason of circumstances other than
        those specified in Rule 7.3 he may within six months of so ceasing
        exercise any Option in whole or in part. To the extent

                                     - 7 -
<PAGE>   10

        that any Option so exercisable is not exercised within such period, it
        shall thereupon cease and determine.

7.5     7.5.1     If, in consequence of any offer made to the holders of
                  Shares, the Directors become aware that the right to cast more
                  than 50 per cent of the votes which may ordinarily be cast on
                  a poll at a general meeting of the Company has or will become
                  vested in the offeror and/or any company controlled by the
                  offeror and/or any person associated with or acting in concert
                  with the offeror, the Directors shall, within 30 days of
                  becoming so aware, notify every Option Holder accordingly.

        7.5.2     An Option Holder shall be entitled at any time during the
                  Change of Control Period to exercise all his Options (whether
                  or not otherwise exercisable) in whole or in part. The Options
                  shall not lapse on the expiry of the Change of Control Period
                  but all Options not exercisable immediately prior to the
                  beginning of the Change of Control Period shall cease to be
                  exercisable on the expiry of the Change of Control Period.

        7.5.3     For the purposes of this Rule 7.5, "Change of Control Period"
                  means the period commencing on the date of the giving of the
                  Directors' notification under this Rule 7.5 and ending three
                  months after that.

        7.5.4     Unless the Directors decide otherwise, the provisions of this
                  Rule 7.5 shall not apply if an Original Shareholder shall
                  become entitled to cast more than 50% of the votes which may
                  ordinarily be cast on a poll at a general meeting of the
                  Company.

7.6     In the event of the proposed dissolution or liquidation of the Company,
        all outstanding Options will terminate immediately prior to the
        consummation of such proposed action, unless otherwise provided by the
        Option Committee; provided, however, that if the rights of a Option
        Holder (or his personal representatives if appropriate) have not
        otherwise terminated and expired, the Option Holder (or his personal
        representatives if appropriate) will have the right immediately prior to
        such dissolution or liquidation to exercise any Option to the extent
        that the Option is exercisable as of the date immediately prior to such
        dissolution or liquidation, and the Option Committee may, in the
        exercise of its sole discretion in such instances, accelerate the date
        on which any Option becomes exercisable or fully vests and/or declare
        that any Option shall terminate as of a specified date.

7.7     If any company (the "Acquiring Company"):.

        7.7.1   obtains control of the Company as a result of making:

               (a)     a general offer to acquire the whole of the issued
                       ordinary share capital of the Company which is made on a
                       condition such that if it is satisfied the Acquiring
                       Company will have control of the Company; or

               (b)     a general offer to acquire all the shares in the Company
                       which are the same class as the ordinary shares which may
                       be acquired by the exercise of Options; in either case
                       ignoring any shares which are already owned by it or a
                       member of the same group of companies; or

                                     - 8 -
<PAGE>   11

        7.7.2   obtains control of the Company in pursuance of a compromise or
                arrangement sanctioned by the Court under Section 425 of the
                Companies Act 1985; or

        7.7.3   becomes bound or entitled to acquire Ordinary Shares under
                Sections 428 to 430F of the Companies Act 1985

                any Option Holder may at any time within the appropriate period
                as defined in paragraph 15(2) of Schedule 9 to the Taxes Act, by
                agreement with the Acquiring Company, release his rights under
                the Scheme in consideration of the grant to him of rights which
                are equivalent but relate to shares in a different company
                (whether the Acquiring Company itself or some other company
                falling within paragraph (b) or (c) of paragraph 10, Schedule 9
                of the Taxes Act). New rights will not be equivalent to old
                rights unless the conditions set out in paragraph 15(3) of
                Schedule 9 to the Taxes Act are satisfied but so that the
                provisions of the Scheme shall for this purpose be construed as
                if:-

                (a)  the New Option were an option granted under the Scheme at
                     the same time as the Old Option; and

                (b)  except for the purposes of the definitions of the Group
                     and Subsidiary in Rule 1, the reference to AP Biotech
                     Inc in the definition of the Company in Rule 1 were a
                     reference to the different company mentioned in this
                     Rule 7.8

7.8     If an Option Holder ceases or has ceased to be an Employee, but at the
        date of the Relevant Anniversary of the Related Savings Contract is an
        employee or executive director of any company which is under the control
        or is an associated company of the Company, he may exercise his Option
        within 6 months of that date.

7.9     In the event of any conflict between any of the provisions of this Rule
        7, the provision which results in the earliest lapsing of the Option in
        question shall prevail.

8.      EXERCISE OF OPTIONS.

8.1     To exercise an Option in whole or in part, an Option Holder must deliver
        to the Secretary of the Company a notice in writing specifying the
        related Repayment Amount and the number of Shares over which the Option
        is exercised and accompanied by either (a) evidence of the termination
        of the Related Savings Contract and by payment in full of the aggregate
        Option Price; or (b) an authority for the Company to terminate the
        Related Savings Contract on the Option Holder's behalf and receive the
        Option Price from the proceeds of that contract. The date of such
        delivery shall constitute the date of such exercise.

8.2     No Option shall be capable of exercise to the extent that the aggregate
        Option Price on such exercise exceeds the related Repayment Amount less
        so much thereof as has already been taken into account upon the exercise
        (in whole or in part) of any Option.

8.3     No Option  shall be capable of exercise in part (other than as to the
        full extent then  exercisable)  as to an aggregate Option Price of less
        than(pound)100.

8.4     Subject to Rule 8.5 below, Shares to be issued pursuant to the exercise
        of an Option shall be allotted within 30 days of the Option Exercise
        Date and the Directors shall procure

                                     - 9 -
<PAGE>   12
        that Shares to be transferred pursuant to the exercise of an Option
        shall be transferred within 30 days following the Option Exercise Date.

8.5     8.5.1     All allotments, issues and transfers of Shares will be
                  subject to such consents (if any) of H M Treasury or other
                  authorities as may for the time being be necessary and it
                  shall be the responsibility of the Option Holder to comply
                  with any requirements to be fulfilled in order to obtain or
                  obviate the necessity for any such consent.

        8.5.2     In a case where any company which is a Member of the Group is
                  obliged to (or would suffer a disadvantage if it were not to)
                  account for any tax (in any jurisdiction) for which the person
                  exercising an option is liable by virtue of the exercise of
                  the option and/or for any social security contributions
                  recoverable from the person in question (together, the "Tax
                  Liability"), no Shares shall be issued or allotted following
                  the exercise of the Option unless that person has either:

                  (a)    made a payment to the Group Company of an amount equal
                         to the Tax Liability; or

                  (b)    entered into arrangements acceptable to that or another
                         Group Company to secure that such a payment is made
                         (whether by authorising the sale or some or all of the
                         shares on his behalf and the payment to the Group
                         Company of the relevant amount out of the proceeds of
                         sale or otherwise).

8.6     If, under the terms of a resolution passed or an announcement made by
        the Company prior to the Option Exercise Date, a dividend is to be or is
        proposed to be paid to holders of Shares on the register on a date prior
        to such Option Exercise Date, the Shares to be issued upon such exercise
        will not rank for such dividend. Subject as aforesaid the Shares so to
        be issued shall be identical and rank pari passu in all respects with
        the fully paid Shares in issue on the Option Exercise Date.

8.7     Where Shares are to be transferred to an Option Holder, he shall be
        entitled to any rights attaching to Shares by reference to a record date
        on or after the date of the Option Exercise Date.

8.8     Subject to Rule 8.9, where an Option is to be satisfied by the transfer
        of Shares by the Trustees any monies received by the Company shall be as
        agent for the Trustees PROVIDED THAT if at any time of exercise:

        8.8.1   an offer (which has not lapsed or been withdrawn) has been made
                (and the offer is recommended, or if not recommended, the Option
                is exercised not earlier than seven days before the first
                closing date of the offer) to acquire the whole or part of the
                share capital of the Company (with or without exceptions for
                persons connected with or acting in concert with the offeror or
                for shares held by such persons) such that if the offer is
                completed the person making the offer will obtain control of the
                Company, whether or not such offer has become or has been
                declared unconditional; or

                                     - 10 -
<PAGE>   13

        8.8.2   an application has been made (and the application has not been
                withdrawn or rejected by the Court) to the Court under Section
                425 of the Companies Act 1985 to sanction a compromise or
                arrangement proposed for the purpose of or in connection with a
                scheme for the reconstruction of the Company or its amalgamation
                with any other company or companies;

                then such payments shall be made to the Company as principal.

8.9     Notwithstanding the provisions of Rule 8.8 above on the exercise of any
        Option the exercise of which is to be satisfied by the transfer of
        Shares from an employee benefit trust established by the Company or any
        company within the same group of companies as the Company (other than a
        trust qualifying as a qualifying employee share ownership trust for the
        purposes of the Finance Act 1989), the monies paid for Shares on
        exercise should be payable to such companies, individual or individuals
        as the Board may from time to time direct.

9.      VARIATIONS

9.1     Upon the occurrence of a Relevant Event:.

        9.1.1   the number or nominal amount of Shares comprised in each
                Option; and/or.

        9.1.2   the Option Price;

        may be adjusted in such manner as the Directors may deem appropriate
        subject to the prior approval of the Inland Revenue and to the written
        concurrence of the Auditors that in their opinion the adjustments
        proposed are fair and reasonable. Adjustments may take effect from the
        date of the Relevant Event. No increase shall be made in the aggregate
        Option Price in relation to any Option.

9.2     This Rule 9.2 applies where an adjustment under Rule 9.1 above would
        have the effect of reducing the Option Price to less than the nominal
        value of a Share. Where an Option subsists over both issued and unissued
        Shares the adjustment may only be made if the reduction of the Option
        Price of Options over issued and unissued Shares can be made to the same
        extent. Any adjustment reducing the option price of unissued shares to
        less than nominal value shall only be made if and to the extent that the
        Board shall be authorised to capitalise from the reserves of the Company
        a sum equal to the amount by which the nominal value of the Ordinary
        Shares in respect of which the Option is exercisable exceeds the
        adjusted Option Price. The Board may apply such sum in paying up such
        amount on such Ordinary Shares so that on exercise of any Option in
        respect of which such a reduction shall have been made the Board shall
        capitalise such sum (if any) and apply the same in paying up such amount
        as aforesaid.

9.3     Options may be adjusted, following variations in the share capital of
        the Company, other than those specified in Rule 9.1 but only with the
        prior approval by Ordinary resolution of the members of the Company in
        general meeting. Any such adjustments shall be made in accordance with
        Rules 9.1 and 9.2 inclusive.

9.4     Notice of any adjustment made pursuant to this Rule shall be given to
        all Option Holders.

                                     - 11 -
<PAGE>   14
10.     ADMINISTRATION

10.1    Any notice or other document which the Company is required or may desire
        to give to any Option Holder pursuant to this Scheme shall be
        sufficiently given if delivered to him (if he is still an Employee) at
        his place of work or sent through the post in a pre-paid cover addressed
        to the Option Holder at his address last known to the Company and if so
        sent shall be deemed to have been duly given on the date of posting. Any
        document so sent to an Option Holder shall be deemed to have been duly
        delivered notwithstanding that he be then deceased (and whether or not
        the Company has notice of his death) except where his legal personal
        representatives have established their title to the satisfaction of the
        Company and supplied to the Company an address to which documents are to
        be sent.

10.2    Option Holders not otherwise entitled thereto shall be sent copies of
        all notices and (so far as appropriate) other documents sent by the
        Company to its shareholders generally.

10.3    The Directors shall have power from time to time to make or vary
        regulations for the administration and operation of this Scheme provided
        that such regulations are not inconsistent with the provisions of this
        Scheme.

11.     GENERAL

11.1    The Directors shall at all times keep available for issue such
        authorised and unissued Shares as may be required to meet all Options
        under which Shares may be subscribed or to procure that sufficient
        Shares are available for transfer to satisfy all Options under which
        Shares may be acquired.

11.2    The decision of the Directors in any dispute or question affecting any
        Option Holder shall be final and conclusive subject to the concurrence
        of the Auditors whenever required under the provisions of this Scheme.

11.3    The Company in General Meeting or the Directors may at any time resolve
        to terminate this Scheme in which event no further Options shall be
        granted but the provisions of this Scheme shall in relation to Options
        then subsisting continue in full force and effect.

11.4    The rights and obligations of any individual under the terms of his
        office or employment with the Company or any member of the Group shall
        not be affected by his participation in the Scheme or any right which he
        may have to participate therein, and an individual who participates
        therein thereby waives all and any rights to compensation or damages in
        consequence of the termination of his office or employment with any such
        company for any reason whatsoever insofar as those rights arise or may
        arise from his ceasing to have rights under or be entitled to exercise
        any Option under the Scheme as a result of such termination or from the
        loss or diminution in value of such rights or entitlements.

12.     ALTERATIONS TO THIS SCHEME

12.1    This Scheme may be altered by the Directors from time to time in any
        manner subject to the following provisions:

        12.1.1  if the approved status of the Scheme is to be maintained no
                amendment or alteration made to the Scheme after it has become
                an Approved Scheme shall have effect unless and until such
                amendment has been approved by the Board of the Inland Revenue;
                and

                                     - 12 -
<PAGE>   15

        12.1.2  no alteration shall be effective to abrogate or alter adversely
                any of the subsisting rights of Option Holders except with the
                consent or sanction of the Option Holders.

13.     GOVERNING LAW

        The Scheme and all Options shall be governed by and construed in
accordance with English law.

                                     - 13 -

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