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                                                                    EXHIBIT 4.18

                       RULES OF THE BOOKHAM TECHNOLOGY PLC

                   2001 APPROVED EMPLOYEE SHARE OPTION SCHEME

        Established by ordinary resolution of shareholders of the Company

          On 13 March 2000 (amended on 26 April 2001 and 12 June 2002)

                           Inland Revenue Ref: X20782

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<Caption>
RULE                                                                                             PAGE NO
<S>                                                                                              <C>
1.       Interpretation                                                                          1

2.       Granting Options                                                                        4

3.       Size of the Scheme                                                                      5

4.       Limits on Employee's Participation                                                      5

5.       When Options can be Exercised.                                                          6

6.       Death of Option-holder                                                                  7

7.       Termination of Employment                                                               7

8.       Changes in Who Controls the Company                                                     8

9.       Changes in the Company's Share Capital                                                  10

10.      How to Exercise Options                                                                 10

11.      Administration                                                                          11

12.      Tax Indemnity                                                                           15

13.      Changing the Scheme                                                                     12

14.      Ending the Scheme                                                                       13
</Table>

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                       RULES OF THE BOOKHAM TECHNOLOGY PLC

                   2001 APPROVED EMPLOYEE SHARE OPTION SCHEME

1      INTERPRETATION

1.1    In this Scheme (unless the context otherwise requires):-

       "ACQUIRING COMPANY" means any company which:-

       -      obtains Control of the Company either:-

              (a)    as a result of making a Takeover Offer; or

              (b)    pursuant to a Compromise; or

       -      serves Section 429 Notices.

       "ACQUIRING PERSON" means any person who either alone or together with any
       person acting in concert with him:-

       -      obtains Control of the Company; or

       -      having Control makes a general offer to acquire the whole of the
              issued share capital of the Company (other than that which is
              already owned by him and/or any person acting in concert with
              him).

       "ACQUISITION PRICE" means the amount payable to exercise an Option, being
       (after any adjustment pursuant to Rule 9) the price per Scheme Share as
       determined by the Board multiplied by the number of Scheme Shares in
       respect of which the Option is exercised. The price of each Scheme Share
       determined by the Board cannot be less than the greater of:-

       -      the nominal value of a Scheme Share; and

       -      the Market Value.

       "ACT" means the Income and Corporation Taxes Act 1988.

       "ADOPTION DATE" means the date on which this Scheme is adopted by the
       Company.

       "APPROPRIATE PERIOD" means:

       -      6 months beginning with the time:-

              (a)    an Acquiring Company or Acquiring Person (as the case may
                     be) obtains Control of the Company and, in the case of a
                     Takeover Offer, any condition subject to which the Takeover
                     Offer is made is satisfied;

              (b)    an Acquiring  Person  having  Control of the Company makes
                     a general offer for the whole of the issued share capital;
                     or

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              (c)    in the case of a Compromise, the court sanctions the
                     compromise or arrangement; or

       -      in relation to a Section 429 Notice, the period during which the
              Acquiring Company is entitled and bound to acquire shares on the
              terms of the offer contained in that Section 429 Notice.

       "AUDITORS" means the auditors for the time being of the Company.

       "BOARD" means the Board of Directors for the time being of the Company,
       the Directors present at a duly convened meeting of that Board of
       Directors or a duly appointed committee of that Board of Directors
       consisting where possible wholly or mainly of non-executive directors of
       the Company.

       "COMPANY" means Bookham Technology plc (company number 2298887) having
       its registered office at 90 Milton Park, Abingdon, Oxfordshire, OX14 4RY.

       "COMPROMISE" means, in relation to the Company, a compromise or
       arrangement sanctioned by the court under section 425 of the Companies
       Act 1985.

       "CONDITION" means a condition or limitation imposed under Rule 2.2.

       "CONTROL" has the same meaning as in section 840 of the Act.

       "DATE OF GRANT" means the date on which an Option is granted to an
       Employee under Rule 2.1.

       "EMPLOYEE" means an employee (other than a director) of a Group Company
       or a full-time director of a Group Company whose hours of work are at
       least 25 hours per week (excluding meal breaks) and who in either case is
       not precluded from participating by paragraph 8 of Schedule 9.

       "EMPLOYEES SHARE SCHEME" means the Bookham Technology plc 1998 Employee
       Share Option Scheme, the Bookham Technology plc 2001 Approved Sharesave
       Scheme, the Bookham Technology Employee Stock Purchase Plan together with
       any arrangement within the meaning of section 743 Companies Act 1985.

       "GROUP COMPANY" means the Company or a company which is for the time
       being a Subsidiary and over which the Company has Control and which has
       been nominated by the Board to participate for the time being in this
       Scheme.

       "LISTING" means the admission to trading or dealing of all or any part of
       the Ordinary Share Capital on a Recognised Investment Exchange.

       "MARKET VALUE" means:-

       -      in the case of Options granted under this Scheme:

              (a)    (if at the relevant time the Scheme Shares are listed on
                     the Daily Official List of the London Stock Exchange) an
                     amount equal to the middle market price of a Scheme Share
                     (as derived from that exchange) on the last dealing

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                     day immediately preceding the Date of Grant or (where the
                     context requires) the Option Rollover date; or

              (b)    (if paragraph (a) above does not apply) the market value of
                     a Scheme Share determined by the Board in accordance with
                     Part VIII of the Taxation of Chargeable Gains Act 1992 and
                     agreed with the Revenue (i) on the Date of Grant or such
                     earlier date or dates as may be agreed with the Revenue but
                     so that no Option may be granted later than 28 days after
                     that value has been agreed or (ii) (where the context
                     requires) the Option Rollover date or

       -      in the case of options granted under any other share option scheme
              approved under the provisions of Schedule 9, the market value of
              an ordinary share determined under the rules of that scheme.

       "OPTION" means a subsisting right to acquire Scheme Shares at the
       Acquisition Price granted to an Employee under the provisions of this
       Scheme. It includes such a right which has been partially exercised.

       "OPTION CERTIFICATE" means a certificate issued under Rule 2.3;

       "OPTION-HOLDER" means any person who holds an Option or (where the
       context admits) his personal representative(s).

       "OPTION NOTICE" means a notice in writing by an Option-holder to exercise
       an Option in the form prescribed by the Board.

       "OPTION ROLLOVER" means in relation to an Option a release by the
       Option-holder with the consent of the Acquiring Company of his rights
       ("old rights") under the Scheme in consideration of the grant to him of
       rights ("new rights") which are equivalent to the old rights but which
       relate to shares in:

       -      the Acquiring Company; or

       -      a company which has Control of the Acquiring Company; or

       -      a company which either is, or has Control of, a company which is a
              member of a consortium owning either the Acquiring Company or a
              company having Control of the Acquiring Company; and

       where the term "equivalent" shall be construed in accordance with
       Rule 8.3.

       "ORDINARY SHARE CAPITAL" means the ordinary share capital of the Company
       as defined in section 832(1) of the Act.

       "QUOTED COMPANY" means a company whose shares are traded on or dealt in a
       Recognised Investment Exchange.

       "RECOGNISED INVESTMENT EXCHANGE" has the same meaning as in section 207
       of the Financial Services Act 1986.

       "REVENUE" means the Commissioners of Inland Revenue.

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       "ROLLED-OVER" means the action of effecting an Option Rollover or its
       completion.

       "SCHEDULE 9" means Schedule 9 of the Act.

       "THIS SCHEME" means this Scheme in its present form or as from time to
       time amended in accordance with the Rules.

       "SCHEME SHARES" means fully paid shares forming part of the Ordinary
       Share Capital for the time being, or any shares representing the same,
       which satisfy the conditions specified in paragraphs 10 to 14 of Schedule
       9.

       "SECTION 429 NOTICE" means in relation to the Company means a notice
       served by a person who has become entitled to serve that notice on the
       shareholders of the Company under section 429 of the Companies Act 1985.

       "SHARE" an ordinary share in the capital of the Company.

       "SUBSIDIARY" means a company which is a subsidiary of the Company within
       the meaning of section 736 of the Companies Act 1985.

       "TAKEOVER OFFER" in relation to the Company means either:

       -      a general offer to acquire the whole of the issued share capital
              of the Company which is made on a condition that if it is
              satisfied the person making the offer will have Control of the
              Company; or

       -      a general offer to acquire all the shares in the Company of the
              same class as the Scheme Shares.

1.2    Words or expressions used in this Scheme shall:-

       1.2.1      when denoting the masculine gender include the feminine;

       1.2.2      when denoting the singular include the plural and vice versa;

       1.2.3      unless the context otherwise requires have the same meanings
                  as in Schedule 9;

       1.2.4      when  referring to any  enactment  be  construed  as a
                  reference to that  enactment as for the time being amended or
                  re-enacted; and

       1.2.5      when referring to "Rules" or a "Rule" throughout this Scheme
                  refer to the Rules of this Scheme.

2      GRANTING OPTIONS

2.1    Subject to statutory  restrictions and subject to the provisions of this
       Scheme, the Board may grant any Employee an Option

2.2    In granting any Option the Board may in their discretion impose any
       objective conditions or limitations (in addition to any conditions or
       limitations in these Rules) on the exercise of that Option; provided that
       those additional conditions or limitations are:

       2.2.1      set out in full in the Option Certificate;

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       2.2.2      so that the Option-holder's right to exercise his Option after
                  the fulfilment or attainment of any conditions and/or
                  limitations shall not depend on the further discretion of any
                  person; and

       2.2.3      capable of being changed if the Board reasonably believes that
                  events have happened which require it to do so to give a
                  fairer measure of performance (provided that any change cannot
                  make the condition more difficult to satisfy than it was
                  before the change took place)

       and the Board shall allow the Option to be exercised in whole or in part
       in accordance with the terms of the Option Certificate.

2.3    All Options shall be granted by a certificate executed by way of Deed
       specifying;

       2.3.1      the Date of Grant;

       2.3.2      the number of Scheme Shares which are the subject of the
                  Option;

       2.3.3      the Acquisition Price; and

       2.3.4      any Conditions.

2.4    An Option-holder may renounce their Option by giving notice in writing to
       the Company. The notice must be received not later than 14 days after the
       Date of Grant of that Option. If this is done, the Option shall be deemed
       never to have been granted.

2.5    Options may only be granted:

       2.5.1      after approval and within 10 years after the Adoption Date;
                  and

       2.5.2      (if at the relevant time the Scheme Shares are not listed on
                  the Daily Official List of the London Stock Exchange) within
                  28 days after the agreement by the Revenue of the Market Value
                  of the Scheme Shares which are the subject of the proposed
                  Option.

2.6    Options are not capable of being transferred, assigned or charged. If an
       Option-Holder purports to transfer, assign or charge an Option, that
       Option will be automatically cancelled. However, if an Option-holder
       dies, his Option may be exercised by his personal representatives under
       Rule 6.

3      SIZE OF THE SCHEME

3.1    Subject to Rules 3.2, 3.3 and 3.4, the number of Shares which may be
       allocated under this Scheme on any day shall not, when aggregated with
       the number of Shares which have been allocated in the previous ten years
       under this Scheme and any other Employees Share Scheme adopted by the
       Company, exceed such number as represents ten per cent (10%) of the
       ordinary share capital of the Company in issue immediately prior to that
       day.

3.2    References in Rule 3.1 to "allocation" of Shares shall mean:

       3.2.1      in the case of any share option scheme:

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                  3.2.1.1   the placing of unissued Shares under option;  and

                  3.2.1.2   insofar as not taken into account under Rule 3.2.1.2
                            above, any subscription for Shares which are issued
                            for the purposes of satisfying any option; and

       3.2.2      in relation to other types of Employees Share Scheme, shall
                  mean the issue and allotment of Shares,

       and references to "allocated" shall be construed accordingly.

3.3    In applying the limit contained in Rule 3.1 no account will be taken of
       Shares subject to an option or other right which has lapsed or been
       released, surrendered or cancelled.

3.4    All options and other rights granted prior to April 18, 2000, the date of
       the Company's initial public offering, shall be disregarded for the
       purposes of Rule 3.1

4      LIMITS ON EMPLOYEE'S PARTICIPATION

4.1    The number of Scheme Shares over which the Board may grant an Option to
       an Employee on any date shall be limited so that the aggregate Market
       Value of those Scheme Shares and any Scheme Shares subject to any other
       subsisting Options or any shares subject to options under any other share
       option scheme (other than a savings relating share option scheme)
       approved under Schedule 9 and established by the Company or any
       associated company of the (Company within the meaning of section 416 of
       the Act) does not exceed L 30,000.

5      WHEN OPTIONS CAN BE EXERCISED

5.1    Save as provided in Rules 6 and 8, an Option cannot be exercised:

       5.1.1      within 3 years after its Date of Grant; and

       5.1.2      unless any Conditions imposed on the Option have been
                  fulfilled.

5.2    An Option cannot be exercised more than 10 years after its Date of Grant.

5.3    The Board acting fairly and reasonably may, if events occur, invite all
       Option-holders to exercise their Options on different terms to those
       stated in Rule 5.1. The Board shall specify in its invitation the period
       in which the Options may be exercised. This may not result in the
       deferral of the exercise of any part of an Option. In exercising its
       discretion under this Rule 5.3, the Board shall not discriminate between
       individual Option-Holders.

5.4    Where it is provided in these Rules that an Option shall lapse, that
       Option shall immediately cease to be exercisable, notwithstanding any
       other provision of these Rules.

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6      DEATH OF OPTION-HOLDER

       If an Option-holder dies, his legal personal representatives may exercise
       all or any of his Options (subject to Rule 5.1) in whole or in part
       within twelve months of his death. Any Options which have not been
       exercised on the expiry of that period shall lapse.

7      TERMINATION OF EMPLOYMENT

7.1    All of an Option-holder's Options shall immediately lapse if he is given
       notice by a Group Company to terminate his employment within the Group.
       They will lapse even if the Group Company is in repudiatory breach of the
       Option-holder's contract of employment.

7.2    If an Option-holder gives notice to terminate his employment within the
       Group, or that employment ceases where Rules 7.3 or 7.4 do not apply, all
       his Options shall immediately lapse. However, the Board may (subject to
       Rule 5.1), consent to the exercise of any Option by the Option-holder
       within 6 months after the later of:-

       7.2.1      the notice; or

       7.2.2      cessation of employment.

7.3    If an Option-holder ceases to be employed by any Group Company by reason
       of:

       7.3.1      injury or disability (and the Board has received satisfactory
                  evidence of this);

       7.3.2      redundancy within the meaning of the Employment Rights Act
                  1996; or

       7.3.3      retirement on reaching retirement age under his contract of
                  employment

       he may, subject to Rule 5.1 exercise all or any of his Options in whole
       or in part within six months after that cessation.

7.4    If any Optionholder ceases being employed in any Group Company solely
       because:-

       7.4.1      the company he is employed by ceases to be a Group Company; or

       7.4.2      the undertaking or part of the undertaking in which the
                  Option-Holder  is employed is transferred to a transferee
                  which is not a Group Company

       then he may, subject to Rule 5.1, exercise all or any of his Options in
       whole or in part six months after that cessation or transfer (as the case
       may be).

7.5    If an Optionholder ceases being employed in any Group Company, his rights
       and benefits under this Scheme or any loss of those rights and benefits
       shall not entitle him to claim for compensation against the Company,
       notwithstanding that he may have been dismissed wrongfully or unfairly
       (within the meaning of the Employment Rights Act 1996).

7.6    The Board may,  subject to  Rule 5.1,  extend the periods of six months
       specified in Rules 7.2, 7.3 and 7.4 up to a maximum period expiring on
       the later of:-

       7.6.1      three years and six months after the Date of Grant; or

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       7.6.2      three years and six months after the last occasion on which
                  the Option-holder exercised an Option in circumstances
                  qualifying for relief from income tax under section 185 of the
                  Act.

7.7    The Options held by an  Option-holder  will lapse if one of Rules 7.2,
       7.3 and 7.4 apply and the periods referred to in those Rules (as they may
       be extended under Rule 7.6) have expired.

8      CHANGES IN WHO CONTROLS THE COMPANY

8.1    If after the Adoption Date an Acquiring Company:

       8.1.1      obtains Control of the Company; or

       8.1.2      serves a Section 429 Notice

       the Board shall as soon as practicable afterwards notify every
       Option-holder accordingly and each Option-holder may within the
       Appropriate Period:

       -      exercise his Options in whole or in part; and

       -      to the extent that an Option has not been  exercised,  execute
              with the consent of the Acquiring Company an Option Rollover

8.2    If Rule 8.1 applies but any Option has not been exercised or Rolled-over
       by the end of the Appropriate Period, that Option shall lapse.

8.3    For the purposes of an Option Rollover the new rights shall only be
       regarded as equivalent to the old rights if:

       8.3.1      the shares to which they relate satisfy the conditions of
                  paragraphs 10 to 14 of Schedule 9;

       8.3.2      the new rights are  exercisable  in the same  manner as the
                  old rights and subject to the provisions of this Scheme as it
                  had effect immediately before an Option Rollover;

       8.3.3      the total Market Value of Scheme Shares subject to an Option
                  which is being Rolled-over is equal immediately before the
                  Option Rollover to the total Market Value (determined in
                  accordance with Part VIII of the Taxation of Chargeable Gains
                  Act 1992) of the shares in respect of which an Option-holder's
                  new rights are being granted immediately after the Option
                  Rollover; and

       8.3.4      the total amount payable in respect of an Option following an
                  Option Rollover is equal to the total Acquisition Price
                  immediately before the Option Rollover.

8.4    For the purposes of any application of the provisions of this Scheme
       following an Option Rollover:

       8.4.1      any new  rights  granted  under  Rule 8  shall  be  regarded
                  as having been granted at the time the corresponding old
                  rights were granted;

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       8.4.2      Rules 8, 9, 10, 11.1, 11.2, and 11.3 shall, in relation to the
                  new rights, have the meanings assigned to them in this Rule
                  8.4 and not the meanings assigned to them in Rule 1.1:

                  "AUDITORS" means the auditors for the time being of the
                  company in respect of whose shares rights have been granted or
                  where there are joint auditors such one of them as the
                  directors of that company shall nominate;

                  "COMPANY" means the new company in respect of whose shares
                  new rights have been granted;

                  "THE BOARD" means the Board of Directors for the time being of
                  the company in respect of whose shares new rights have been
                  granted, the directors present at a duly convened meeting of
                  that Board of Directors or a duly appointed committee of that
                  Board of Directors; and

       8.4.3      for the purposes of Rules 3, 7, 8, 9, 10, 11.1, 11.2, and 11.3
                  the following terms shall, in relation to the new rights, have
                  the following meanings and not the meanings assigned to them
                  in Rule 1.1:

                  "SCHEME SHARES" means fully paid ordinary shares in the
                  capital of the company over whose shares new rights have been
                  granted and which satisfy the conditions specified in
                  paragraphs 10 to 14 of Schedule 9;

                  "SHARES" means ordinary shares in the capital of the company
                  over whose shares new rights have been granted; and

                  "SHARES SUBJECT TO THIS SCHEME" means Scheme Shares.

8.5    If after the Adoption Date an Acquiring Person:-

       8.5.1      obtains Control of the Company; or

       8.5.2      having  Control of the Company  makes a general offer to
                  acquire the whole of the issued share capital of the Company

       the Board shall as soon as practicable afterwards notify every
       Option-holder accordingly and each Option-holder may within the
       Appropriate Period exercise his Options in whole or part. If this Rule
       8.5 applies but any Option has not been exercised by the end of the
       Appropriate Period, that Option shall lapse.

8.6    If notice is duly given of a General Meeting at which a resolution will
       be proposed for the voluntary winding-up of the Company (other than for
       the purposes of reconstruction or amalgamation) an Option shall, subject
       to Rule 5.1, be exercisable in whole or part. Any exercise of an Option
       under this Rule 8.6 shall be conditional on the passing of that
       resolution. An Option may be exercised under this Rule 8.6 at any time
       after the notice is given until the resolution is duly passed, defeated
       or the Meeting is concluded or adjourned, whichever happens first. If the
       resolution is passed, any Options which have not been exercised shall
       lapse.

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9      CHANGES IN THE COMPANY'S SHARE CAPITAL

       If the share capital of the Company is changed by way of a
       capitalisation, open offer, rights issue, or any reduction, sub-division
       or consolidation, the following things shall be adjusted by the Board:-

9.1    the number of shares subject to this Scheme and/or comprised in any
       Option; and/or

9.2    the Acquisition Price per Scheme Share.

       Any adjustment must be in a way that the Auditors have confirmed in
       writing to be in their opinion fair and reasonable. No adjustment may be
       made without the prior approval of the Revenue or which would cause the
       price per Scheme Share to be less than the nominal value of that Scheme
       Share. Notice of any adjustment shall be given to the Option-holders by
       the Board who may call in Option Certificates for endorsement.

10     HOW TO EXERCISE OPTIONS

10.1   Exercise of an Option or new rights under this Scheme may be in whole or
       in part. It is done by the Option-holder giving the Company an Option
       Notice, together with payment in full for the Scheme Shares concerned.
       The date of exercise of the Option shall be the date that the Option
       Notice is received or deemed to be received by the Board in accordance
       with Rule 11.2.

10.2   An Option Rollover under Rule 8 of this Scheme is done by the
       Option-holder giving the Company a notice in writing in a form prescribed
       by the Board. The Option Rollover shall be executed within the
       Appropriate Period.

10.3   All allotments and issues of Scheme Shares are subject to any necessary
       consents of H.M. Treasury or other authorities in the United Kingdom or
       elsewhere. It is the responsibility of the Option-holder to comply with
       any requirement so that a consent is not necessary.

10.4   No option may be  exercised  by an  Option-holder  at any time if he is
       precluded by paragraph 8 of Schedule 9 from participating in this Scheme.

10.5   The Company shall, within 28 days after receiving an Option Notice, allot
       and issue as fully paid to the Option holder and register in his name the
       number of Scheme Shares specified in the Option Notice. The Company shall
       within the same period deliver to the Option-holder an appropriately
       endorsed share certificate in respect of those Scheme Shares together
       with (in the case of a partial exercise of an Option) an Option
       Certificate for the balance of the Option-holder's Options.

10.6   Unless there are rights attaching to Scheme Shares by reference to a
       record date before the date on which the Scheme Shares are allotted and
       issued, all Scheme Shares which are issued on the exercise of Options
       shall be identical and will rank pari passu in all respects with the
       Scheme Shares then in issue.

10.7   If the Company is a Quoted Company at the time when an option is
       exercised, the Company shall use its best endeavours to ensure that, as
       soon as practicable after the

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       allotment of any Scheme Shares under this Scheme, those Scheme Shares
       shall be admitted to the relevant Recognised Investment Exchange.

11     ADMINISTRATION

11.1   The Company shall maintain enough authorised and unissued Scheme Shares
       to satisfy the exercise to the full extent still possible of all Options
       which have neither lapsed nor been fully exercised, and taking account of
       any other obligations of the Company to issue unissued Scheme Shares.

11.2   Any notice or other document required to be given to any Option-holder
       under these Rules shall be delivered to him or sent by post to him at his
       home address according to the records of the Company or to any other
       address that appears appropriate to the Board. Any notice or other
       document required to be given to the Board shall be delivered to them or
       sent by post to them care of the registered office of the Company.
       Notices sent by post shall be deemed to have been given on the second day
       after the date of posting.

11.3   The Company shall not be obliged to provide Option-holders with copies of
       any notices, circulars or other documents sent to holders of Scheme
       Shares.

11.4   The Directors by resolution may at any time resolve that no further
       Options be granted under this Scheme. If they do this, no further Options
       will be granted but in all other respects this Scheme shall remain in
       force.

11.5   If the Auditors are required to act under these Rules, they shall be
       deemed to be acting as experts and not as arbitrators and their decision
       shall be final and binding. Subject to that, the decision of the Board in
       any dispute or question relating to any Option or to the interpretation
       of the Rules shall be final and conclusive.

11.6   The Company shall pay the costs of introducing and administering this
       Scheme.

12     TAX INDEMNITY

12.1   Each Option-holder must indemnify each Group Company against any
       Option-holder's tax liability on the grant or exercise of an Option where
       that Group Company must account for the tax to any tax authority. This
       includes, without limitation, any Group Company's obligation to account
       to the Inland Revenue for PAYE on the exercise of any Option.

12.2   Where any Group Company must account for any tax under Rule 12.1, the
       Company may:-

       12.2.1     require the  Option-holder  to pay the amount of the tax to
                  the relevant  Group Company before the Option may be
                  exercised;

       12.2.2     deduct the amount of the tax from the Option-holder's salary;
                  or

       12.2.3     (with the consent of the Option-holder) withhold any Scheme
                  Shares and sell them on behalf of the Option-holder up to the
                  amount necessary to pay the tax (and any other taxes or duties
                  arising on the sale) and any costs of sale.

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12.3   The secretary for the time being of the Company (or any other person that
       the Board nominates) is appointed the Option-holder's attorney to sell
       Scheme Shares pursuant to Rule 12.2.3 and to execute all necessary
       transfer forms or other documents in connection with the sale.

12.4   For the purpose of this Rule 12 and for Rule 13.6 "tax" includes income
       tax, capital gains tax, national insurance, stamp duty and any other
       taxes or duties of any kind in any country.

13     CHANGING THE SCHEME

13.1   The Board may at any time make any necessary alterations (including
       additions) to the Rules of the Scheme to secure that they receive initial
       approval from the Revenue under Schedule 9 and continue to be approved.

13.2   Subject to Rules 13.1 and 13.4, the Board may from time to time amend any
       of the Rules of this Scheme provided that, except with the prior approval
       of the Company in General Meeting, no amendment to the advantage of
       Option-holders shall be made to:

       13.2.1     the definitions in Rule 1.1 of:-

                  -      Employee;

                  -      Market Value;

                  -      Scheme Shares; or

                  -      Acquisition Price; or

       13.2.2     Rules 2.1, 2.6, 3, 9, 10.6, 13.2, and 13.4

       SAVE THAT the Board may make changes to the Rules listed in Rules 13.2.1
       and 13.2.2 if the change is, in the opinion of the Board, a minor
       amendment:

       -      to benefit the administration of this Scheme; or

       -      to take account of a change in legislation or to maintain Inland
              Revenue approval or obtain or maintain favourable tax, exchange
              control or regulatory treatment for existing or new Option-holders
              or for any Group Company; and

       -      no such alternation or addition to any provision of this Scheme
              shall be made in relation to Options granted by a body other than
              the Company without the consent of such grantor.

13.3   Subject to Rule 13.1, no amendment, waiver or replacement to this Scheme
       may be made which would have the effect of abrogating or altering
       adversely any of the subsisting rights of Option-holders unless they give
       their consent. The consent that is required is the same as that which
       would be required by the Company's Articles of Association if the Scheme
       Shares that would be issued on the exercise of all the unexercised
       Options were issued and constituted a separate class of share capital.

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13.4   No amendment to this Scheme will have effect until it has been approved
       in advance by the Revenue.

13.5   Written notice of any amendment made or to be made in accordance with
       this Rule 13 and which materially affects the rights of existing
       Option-holders shall be given to those Option-holders.

13.6   The Board shall have the power from time to time to make or vary
       regulations for the administration of the Scheme and to impose further
       conditions on the grant and exercise of Options to take account of
       overseas tax and securities laws. However, those regulations and
       conditions shall not be inconsistent with the provisions of this Scheme
       and shall not stop this Scheme from satisfying Schedule 9. If there is
       any dispute or disagreement as to the interpretation of this Scheme or of
       those regulations or conditions or as to any question or right arising
       from or related to this Scheme, the decision of the Directors shall (save
       for any matter which has to be determined by the Auditors under this
       Scheme) be final and binding upon all persons.

14     ENDING THE SCHEME

       This Scheme may be terminated at any time by a resolution of the Board
       after consultation with the Directors or by a resolution of the Company
       in General Meeting. It shall in any event terminate on the tenth
       anniversary of the Adoption Date. Any termination shall not affect the
       outstanding rights of any Option-holder.