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                                                                   Exhibit 10.22




                                TABLE OF CONTENTS

                                                                            Page

                                  DATED - 2001

                                REUTERS GROUP PLC

                                       and

                              INSTINET GROUP, INC.

                                       and

                            INSTINET HOLDINGS LIMITED

                 -----------------------------------------------

                       TAX SHARING AND INDEMNITY AGREEMENT

                 -----------------------------------------------
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THIS AGREEMENT IS MADE THIS      DAY OF MAY 2001

BETWEEN:-

(1)      REUTERS GROUP PLC ("Reuters"), a company incorporated in England and
         Wales (registered number 3296375) whose registered office is at 85
         Fleet Street, London and its lawful successors or assigns;

(2)      INSTINET GROUP, INC., (formerly Instinet Group LLC) ("Instinet") a
         limited liability company whose registered office is at 3 Times Square,
         New York, NY 10036, USA and its lawful successors or assigns; and

(3)      INSTINET HOLDINGS LIMITED ("Holdings"), a company incorporated in
         England and Wales (registered number 1416500) whose registered office
         is at 85 Fleet Street, London and its lawful successors and assigns.

WHEREAS:-

(A)      Reuters directly and indirectly contributed the entire share capital of
         Holdings to LLC on 29th September, 2000; (B) On 9th May, 2001 LLC
         became Instinet and Instinet assumed all of LLC's liabilities; and

(C)      The parties hereto have agreed to enter into this Agreement to provide
         for the basis on which past and future Tax Liabilities other than Tax
         Liabilities covered by the terms of the US Agreement (as defined in
         clause 2 below) will be allocated between Holdings and its Subsidiaries
         on the one hand and Reuters and its Subsidiaries (other than LLC and
         all its Subsidiaries) on the other hand.

NOW THIS AGREEMENT WITNESSES as follows:-

 1.1     DEFINITIONS.

         In this Agreement, the following words and expressions have the
meanings set opposite them:-

       "arm's length basis"             means such arrangements or provisions
                                        which would be expected to be made
                                        between independent enterprises;

       "Annual Accounts"                means the annual accounts of any
                                        Instinet International Company
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                                        prepared in respect of an accounting
                                        period of that company commencing on or
                                        before 31st December, 2000. If any such
                                        annual accounts are audited or prepared
                                        for any statutory purpose the audited or
                                        statutory version shall constitute the
                                        annual accounts for such Company for the
                                        period in question;

       "Company" or "Companies"         means any company to which this
                                        Agreement applies;

       "ICTA"                           means the Income and Corporation
                                        Taxes Act 1988;

       "Instinet International
        Business"                       means any business carried on by any
                                        Instinet International Company;

       "Instinet International
        Companies" or "Instinet
        International Company"          means Holdings and all its
                                        Subsidiaries as at 30th September, 2000,
                                        together with any Subsidiaries acquired
                                        or established after that date and
                                        Instinet Schweiz, AG, Instinet Bermuda
                                        Limited and Instinet Investments
                                        (Bermuda) Limited;

       "a continuing Reuters
        company" and "continuing
        Reuters companies"              means Reuters and any and all direct
                                        and indirect Subsidiaries (whether or
                                        not resident in the UK for tax purposes)
                                        of Reuters except LLC and all its
                                        Subsidiaries as at 30th September, 2000
                                        and any Subsidiaries of LLC acquired
                                        after that date;

       "Instinet Tax Liabilities"       means all Tax Liabilities in respect of
                                        profits, deemed profits, activities,
                                        turnover, supplies or transactions
                                        arising in any way in the course of any
                                        business conducted by an Instinet
                                        International Company at any time
                                        before, on or after 31st December, 2000
                                        including any Tax Liability arising in
                                        respect of any disposal or deemed
                                        disposal of
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                                        shares of any company conducting any
                                        such business subject to the provisions
                                        of sub-clauses 1.2 to 1.4 (inclusive)
                                        below, but excluding any Tax Liability
                                        to the extent that:-

                                        (a)     the Tax Liability was paid or
                                                otherwise discharged before the
                                                date of this Agreement; or

                                        (b)     the Tax Liability would not have
                                                arisen but for the making of a
                                                claim, election, surrender or
                                                disclaimer, the giving of a
                                                notice or consent, or the doing
                                                of any other thing under the
                                                provisions of any enactment or
                                                regulation relating to Tax, in
                                                each case after the date of this
                                                Agreement and by a continuing
                                                Reuters company; or

                                        (c)     the Tax Liability would not have
                                                arisen but for a voluntary
                                                transaction, action or omission
                                                carried out or effected by any
                                                continuing Reuters company at
                                                any time after the date of this
                                                Agreement, other than any such
                                                transaction, action or omission
                                                carried out or effected by any
                                                continuing Reuters company:-

                                                (i)     under a legally binding
                                                        commitment created on or
                                                        before the date of this
                                                        Agreement; or

                                                (ii)    with the prior consent
                                                        of LLC or any Instinet
                                                        International Company;
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       "LLC"                            means Instinet Group LLC, a Delaware
                                        limited liability company and (save
                                        where the context otherwise requires)
                                        its lawful successors and assigns;

       "non-Instinet Tax Liabilities"   means all Tax Liabilities other than
                                        Instinet Tax Liabilities;

       "Restructuring"                  means the series of transactions carried
                                        out under:-

                                        (a)     the Contribution Agreement
                                                entered into between Reuters C
                                                Corp and LLC dated 29th
                                                September, 2000;

                                        (b)     the Contribution Agreement
                                                entered into between Reuters
                                                Holdings Switzerland SA and LLC
                                                dated 29th September, 2000;

                                        (c)     the Asset Contribution Agreement
                                                entered into between Instinet
                                                Corporation and LLC dated 31st
                                                July, 2000; and

                                        (d)     the Contribution Agreement
                                                entered into between Instinet
                                                Corporation and LLC dated 25th
                                                July, 2000;

       "Subsidiaries"                   means:-

                                        (a)     in relation to Holdings any
                                                company in which Holdings owns
                                                directly or indirectly more than
                                                50 per cent. of its ordinary
                                                share capital; and
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                                        (b)     in relation to Reuters any
                                                company in which Reuters owns
                                                directly or indirectly more than
                                                50 per cent. of its ordinary
                                                share capital but excluding LLC
                                                (including the Subsidiaries of
                                                LLC) and Holdings (including the
                                                Subsidiaries of Holdings);

                                        and "Subsidiary" shall be construed
                                        accordingly;

       "Tax" or "Taxation"              means:-

                                        (a)     all forms of taxation, including
                                                any charge, tax, duty, levy,
                                                impost withholdings in the
                                                nature of taxation, including
                                                (without limitation) any excise,
                                                property, sales, use,
                                                occupation, transfer, franchise,
                                                value added and payroll taxes,
                                                and any national insurance or
                                                social security contributions or
                                                liability whether chargeable
                                                imposed for the support of
                                                national, state, federal,
                                                municipal or local government or
                                                any other person and whether of
                                                the United Kingdom or any other
                                                jurisdiction; and

                                        (b)     any penalty, fine, surcharge,
                                                interest, charges or costs
                                                payable in connection with any
                                                tax within the meaning of
                                                paragraph (a) above;

       "Tax Authority"                  means any taxing or other authority
                                        (whether within or outside the United
                                        Kingdom) competent to impose any Tax
                                        Liability;
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       "Tax Item"                       means any item of income, gain, loss,
                                        deduction or credit, or other asset that
                                        may have the effect of increasing or
                                        decreasing any liability to Tax;

       "Tax Liabilities" or
       "Tax Liability"                  means any liability of a Company to make
                                        a payment of or in respect of Taxation
                                        whether or not the same is primarily
                                        payable by that Company and whether or
                                        not that Company has or may have any
                                        right of reimbursement against any other
                                        person or persons;

       "Loss"                           means any reduction, modification, loss,
                                        counteraction, nullification,
                                        utilisation, disallowance, withdrawal or
                                        clawback for whatever reason; and

       "Relief"                         means any loss, relief, allowance,
                                        credit, exemption or set-off in respect
                                        of Taxation or any deduction in
                                        computing income, profits or gains for
                                        the purposes of Taxation.

1.2    ALLOCATION OF TAX LIABILITY COMPUTED ON A CONSOLIDATED BASIS.

       In any case where in a jurisdiction Tax is charged or collected or
       computed on any consolidated basis so that Tax in respect of an Instinet
       International Business may be charged, collected or recovered from a
       continuing Reuters company or vice versa, then the nature of the Tax
       Liability shall be determined according to the business to which the
       liability is referable and not by reference to the Company on which it
       may be chargeable and the amount of the relevant Tax shall be determined
       by making all reasonable apportionments of overall liabilities and by
       treating companies as if they had dealt with each other on an arm's
       length basis so as to ascertain the liability that would have been an
       Instinet Tax Liability and a non-Instinet Tax Liability had those
       respective liabilities been calculated on a stand alone, rather than any
       form of consolidated, basis.
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1.3      DEEMED NON-INSTINET TAX LIABILITY.

         Subject to sub-clause 1.4 below, any Tax Liability of a continuing
         Reuters company referable to its disposal of shares in an Instinet
         International Company or to any receipt of a dividend from such a
         company or to the Restructuring or which is referable to any other
         transaction which a continuing Reuters company has entered into with an
         Instinet International Company shall be treated as a non-Instinet Tax
         Liability.

1.4      DEEMED INSTINET TAX LIABILITY.

         (i)      Any liability of any Company to stamp duty, any equivalent
                  transaction Tax or capital duty occasioned in any way by way
                  of the transactions necessitated by the reorganisation of
                  Instinet International Companies within Holdings, and the
                  direct and indirect contribution of Holdings to LLC, and any
                  such liability occasioned by the transfer and contribution of
                  Instinet Schweiz, AG, Instinet Bermuda Limited and Instinet
                  International (Bermuda) Limited to LLC shall be an Instinet
                  Tax Liability.

         (ii)     Any future liability to stamp duty, capital duty and any
                  transaction Tax equivalent to stamp duty occasioned by the
                  withdrawal or other forfeiture of any Relief shall also
                  constitute an Instinet Tax Liability if the duty would
                  initially have been paid on or in respect of one of the
                  transactions referred to above but for the initial
                  availability of the Relief or exemption which has been
                  forfeited or has been the subject of withdrawal.

2.       PRIORITY OF US AGREEMENT.

         This Agreement shall not apply to any Tax Liability to the extent that
         it is covered by the terms of the Tax Sharing Agreement dated the same
         date as this Agreement and made between Reuters America Holdings, Inc.,
         Instinet Group, LLC and Instinet Global Holdings, Inc. (the "US
         Agreement").

3.       TAX LIABILITIES COVERED BY EXISTING PROVISIONS.

         Insofar as provision or reserve for Tax Liabilities has been made or
         provided for in the Annual Accounts of any Instinet International
         Company or the equivalent accounts of any continuing Reuters company
         for any period ending on or prior to 31st December, 2000, no adjustment
         shall be made to such Tax
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         Liabilities from the treatment provided for or reserved in the relevant
         accounts.

4.       PAST UNPROVIDED FOR TAX LIABILITIES.

         Insofar as any unprovided for Tax Liability arises in respect of any
         period ending on or prior to 31st December, 2000, that Tax will be
         borne by an Instinet International Company if and to the extent that
         the Tax Liability in question is an Instinet Tax Liability and it shall
         be borne by a continuing Reuters company if and to the extent that the
         Tax Liability is a non-Instinet Tax Liability. Reuters and LLC shall
         respectively procure that appropriate Instinet International Companies
         and continuing Reuters companies make the required payments, on a
         timely basis, to achieve the above objective and failing any such
         procurement Reuters and LLC will themselves make payments, on a timely
         basis, to achieve the relevant objective.

5.       FUTURE TAX LIABILITIES.

         For all periods ending after 31st December, 2000 Instinet International
         Companies shall bear and indemnify continuing Reuters companies against
         all Instinet Tax Liabilities and continuing Reuters companies shall
         bear and indemnify Instinet International Companies against all
         non-Instinet Tax Liabilities, Reuters and LLC themselves making
         payments, on a timely basis, to achieve the objective of this clause in
         the event of either of them failing to procure that other Companies
         make the required payments on a timely basis.

6.       FUTURE GROUP RELIEF ARRANGEMENTS ETC.

         Where the system of Taxation operating in any jurisdiction computes and
         charges Tax Liabilities on companies on a company by company basis but
         permits companies within any given relationship with others to
         surrender Tax losses of any description (whether income or capital in
         nature) to other companies, then for all periods on and after 31st
         December, 2000 any such surrenders involving both an Instinet
         International Company and a continuing Reuters company shall be dealt
         with on an arm's length basis and the respective parties to the
         surrender and claim shall agree the payment that is to be made for any
         Tax losses and all appropriate subsequent adjustments (including
         payment of interest where necessary) and refunds should the initial
         expected surrender of Tax losses be challenged by the Tax Authorities
         or prove ineffective in any way.
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7.       FUTURE POOLING OF CAPITAL GAINS AND LOSSES BETWEEN DIFFERENT COMPANIES.

         In the case of any system of Tax where assets can be transferred by one
         company to another on a basis whereunder the acquiring company assumes
         the latent Tax gains or losses of the transferring company referable to
         the asset or where companies can elect that the capital gains or losses
         of one company shall be treated as being realised or incurred by
         another company, then where such transfers or surrenders of gains or
         losses are made between an Instinet International Company and a
         continuing Reuters company the terms on which all such transfers and
         surrenders are made shall be agreed on an arm's length basis, with all
         appropriate provision being made for adjustment should the initial
         expectations need adjustment in any changed circumstances.

8.       UNCHALLENGED PAST SURRENDERS OF GROUP RELIEF ETC.

8.1      Subject to sub-clause 8.2 below, where such a system of Tax as is
         mentioned in clause 6 above was in operation for accounting periods
         ending on or before 31st December, 2000 and an Instinet International
         Company, prior to the date of this Agreement, has either surrendered
         Tax losses to a continuing Reuters company or vice versa, and the
         relevant surrender proves to be effective, then no adjustment shall be
         made to the existing accounts treatment of the surrender and to any
         payment that may have been made by any Company in respect of that
         surrender which has been taken into account in the relevant accounts.

8.2      If any Instinet International Company amends any provision relating to
         Tax losses in respect of an accounting period to which this clause 8
         applies as a result of which such Tax losses are increased and the
         relevant Tax Authorities accept such amendment then, if payment was
         initially made by the claimant Company for the Tax losses, an
         additional payment shall be made to the surrendering Company on such
         terms as would have been agreed between the parties had they been
         acting on an arm's length basis and the Tax rate to be applied to the
         increase in the Tax losses shall be negotiated by the parties.

9.       CHALLENGED PAST SURRENDERS OF GROUP RELIEF ETC.

         Where clause 8 would have applied but for the fact that the Tax
         Authorities have either challenged the surrender of losses or because
         the losses have not been used as initially contemplated
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         (either because of insufficiency of profits or losses), then, if
         payment was initially made by the claimant Company for the Tax losses:-

         (i)      if the agreement between the Companies originally provided for
                  appropriate adjustments and refunds to be made in the event of
                  a claim being disputed those provisions shall take effect;

         (ii)     subject to sub-paragraph (iii) below, where any agreement for
                  surrender was silent as to such matters but payment was still
                  made, such refund will be made as would have been agreed
                  between the parties had they been acting on an arm's length
                  basis, taking into account the Tax Liability that the claimant
                  Company may have to bear and any revived value of losses to
                  the Company that originally sought to surrender those losses
                  in the light of the changed circumstances; and

         (iii)    any refund referred to in sub-paragraph (ii) above in respect
                  of a past provision shall be made at the rate of corporation
                  tax in force at the date the relevant surrender of Tax losses
                  was made.

10.      CHALLENGED SURRENDER OF TAX LOSSES.

         Where clause 8 would have applied but for the fact that no payment was
         initially made to the surrendering Company for the surrender of its Tax
         losses then in the event that the surrender is challenged in either of
         the ways contemplated in clause 9, no adjustment payments will be made
         unless it was expressly agreed that a payment would be made in such a
         situation.

11.      PAST POOLING OF CAPITAL GAINS AND LOSSES BETWEEN DIFFERENT COMPANIES.

         Where a system of Tax contains such provisions as are referred to in
         clause 7 above, and assets have been transferred or Taxable profits or
         losses have effectively been transferred between an Instinet
         International Company and a continuing Reuters company for an
         accounting period ending on or prior to 31st December, 2000, then the
         general principles contained in clauses 7 to 10 shall be applied to the
         transfer of the assets or the surrender of the losses according to
         whether the latent liabilities passed to the transferee Company as
         initially expected, or whether any revisions have to be made on account
         of
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         either a challenge of the transfer or election by the Tax Authorities
         or the assumed latent gains or losses being of a different amount than
         initially contemplated.

12.      CONTROLLED FOREIGN COMPANIES PROVISION.

12.1     In the event that a continuing Reuters company is charged to Tax under
         the United Kingdom controlled foreign companies provisions as contained
         in Part XVII, Chapter IV ICTA (as amended from time to time) (the "CFC
         provisions") in respect of the distributed or undistributed profits of
         an Instinet International Company that ranks as a controlled foreign
         company for the purposes of those provisions, then that Tax Liability
         will be treated for the purposes of this Agreement as an Instinet Tax
         Liability. LLC shall procure that appropriate Instinet International
         Companies make the required payments, on a timely basis, to achieve the
         above objective.

12.2     In the event that profits that are the subject of an apportionment
         under the CFC provisions are distributed directly or indirectly by way
         of dividend to a continuing Reuters company, then the Tax that would
         have been chargeable in the United Kingdom on that dividend, had there
         been no credit or offset for UK Tax charged under the CFC provisions in
         respect of the underlying profits which were apportioned to the
         continuing Reuters company, shall be treated as a non-Instinet Tax
         Liability and the amount initially treated as an Instinet Tax Liability
         in respect of the initial apportionment shall retrospectively be
         adjusted and shall only be treated as an Instinet Tax Liability to the
         extent that the UK Tax Liability in respect of the controlled foreign
         companies apportionment exceeded the Tax Liability that would have
         arisen on the actual dividend received had there been no credit or
         offset, in calculating the Tax on the dividend for any UK Tax charged
         under the CFC provisions in respect of the apportionment, and the
         balance of the Tax charged in respect of the apportionment shall be
         treated as a non-Instinet Tax Liability. Reuters and LLC shall procure
         that appropriate continuing Reuters companies and Instinet
         International Companies (as applicable) make the required payments, on
         a timely basis, to achieve the above objective.

13.      EXCHANGE OF INFORMATION.

         Reuters and LLC shall provide such information to each other, and shall
         procure that continuing Reuters companies and Instinet
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         International Companies respectively provide such information as may be
         reasonably required:-

         (i)      for the proper calculation of all liabilities under this
                  Agreement;

         (ii)     to enable all companies to compute and record their proper Tax
                  Liabilities; and

         (iii)    to enable continuing Reuters companies to seek and obtain
                  consents under section 765 ICTA, whenever required.

14.      SECTION 765 ICTA.

         LLC shall not and shall procure that no Instinet International Company
         shall enter into any transaction or transactions to which Section 765
         ICTA applies without first obtaining the consent of H.M. Treasury as
         required by that section.

15.      TAX RETURNS.

15.1     Subject to the last sentence of this sub-clause 15.1, LLC shall have
         the exclusive right to determine with respect to any Tax return of
         either LLC or any Instinet International Company:

         (i)      the manner in which such Tax return or Tax Items shall be
                  prepared and filed, including the elections, methods of
                  accounting, positions, conventions and principles of Taxation
                  to be used and the manner in which any Tax Item shall be
                  reported;

         (ii)     whether any extensions may be requested;

         (iii)    the elections that will be made by LLC or any Instinet
                  International Company on such Tax return or with respect to
                  such Tax Items;

         (iv)     whether any amended Tax returns shall be filed;

         (v)      whether any claims for refund shall be made;

         (vi)     whether any refunds shall be paid by way or refund or credited
                  against any liability for the related Tax; and

         (vii)    whether to retain external firms to prepare or review such Tax
                  returns or Tax Items
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         PROVIDED THAT if Reuters and any continuing Reuters company together
         own directly or indirectly 50 per cent. or more of the outstanding
         stock (by reference to votes or value) of LLC:

                  (b)      Reuters shall, by the end of the relevant accounting
                           period, designate and notify LLC of the Tax returns
                           that it wishes to review and approve and LLC shall
                           submit such Tax returns to Reuters no later than
                           fifteen business days prior to the due date for the
                           filing of such Tax returns (taking into account
                           applicable extensions) for Reuters' review and
                           approval (such approval shall not be unreasonably
                           withheld); and

                  (c)      Reuters shall have the right to re-determine the
                           manner in which any Tax Item of LLC or any Instinet
                           International Company included in such Tax returns
                           including any other matters listed in sub-paragraphs
                           (i) to (vii) (inclusive) of this sub-clause 15.1 is
                           reported if the proposed reporting of such Tax Item
                           would adversely affect the Tax treatment of Reuters
                           or any continuing Reuters company to a meaningful
                           extent,

         PROVIDED FURTHER THAT the revised treatment of such Tax Item could not
         result in the imposition of penalties on LLC or any Instinet
         International Company. To the extent that any Tax Items of any
         continuing Reuters company are included on any Tax return of either LLC
         or any Instinet International Company, Reuters shall have the right to
         determine the manner in which such Tax Items are reported.

15.2     In the event that a Tax Item in a Tax return of any continuing Reuters
         company corresponds to a Tax Item in a Tax return of either LLC or any
         Instinet International Company that is filed after the date of this
         Agreement, then LLC shall or shall procure that the relevant Instinet
         International Company preparing, or causing the preparation of, such
         Tax return shall conform the treatment of the relevant Tax Item in such
         Tax return to the treatment of such Tax Item in the relevant Tax return
         of the continuing Reuters company PROVIDED THAT the revised treatment
         of such Tax Item could not result in the imposition of penalties on LLC
         or any Instinet International Company AND PROVIDED FURTHER THAT Reuters
         and any other continuing Reuters company together own directly or
         indirectly 50 per cent. or more of the outstanding stock (by reference
         to votes or value) of LLC.
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15.3     LLC shall and shall procure that each Instinet International Company
         shall provide all reasonable and necessary information to Reuters or
         its agents in order to facilitate the preparation of any Tax return
         filed after the date of this Agreement by any continuing Reuters
         company (including the making of any related elections) to the extent
         that such Tax return relates exclusively to LLC or to any Instinet
         International Company or to any of the assets, businesses and/or
         entities transferred to any Instinet International Company as part of
         the Restructuring. LLC shall procure that this information is submitted
         to Reuters at least 45 business days (or such shorter period as is
         agreed to by Reuters) prior to the due date for the filing of such Tax
         return (taking into account any applicable extensions). LLC or the
         relevant Instinet International Company shall bear its pro rata share
         of the costs associated with the preparation of such Tax return.

16.      REMEDIES AND WAIVERS.

16.1     No delay or omission by any party to this Agreement in exercising any
         right, power or remedy provided by law or under this Agreement or any
         other documents referred to in it shall:-

         (i)      affect that right, power or remedy; or

         (ii)     operate as a waiver thereof.

16.2     The single or partial exercise of any right, power or remedy provided
         by law or under this Agreement shall not preclude any other or further
         exercise of it or the exercise of any other right, power or remedy.

16.3     The rights, powers and remedies provided in this Agreement are
         cumulative and not exclusive of any rights, powers and remedies
         provided by law.

17.      ASSIGNMENT.

17.1     The rights, interests and obligations under this Agreement are personal
         to the parties and shall not be assigned, delegated, transferred or
         otherwise disposed of without the prior written consent of the other
         parties.

17.2     This Agreement and all of the provisions hereof shall be binding upon
         and inure to the benefit of the parties and their respective successors
         and permitted assigns.
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18.      ENTIRE AGREEMENT.

18.1     This Agreement shall constitute the entire agreement between the
         parties relating to the past and future allocation of Tax Liabilities
         between them.

18.2     Except in the case of fraud, no party shall have any right of action
         against any other party to this Agreement arising out of or in
         connection with any draft agreement, undertaking, representation,
         warranty, promise, assurance or arrangement of any nature whatsoever,
         whether or not in writing, relating to the subject matter of the
         Agreement made or given by any person at any time prior to the date of
         this Agreement except to the extent that it is repeated in this
         Agreement.

18.3     This Agreement may only be varied in writing signed by each party.

19.      NOTICES.

19.1     All notices, requests, demands and other communications under this
         Agreement shall only be effective if in writing.

19.2     Notices under this Agreement shall be sent to a party at its address or
         number and for the attention of the individual set out below:-

       PARTY AND TITLE OF            ADDRESS
       INDIVIDUALS

       Director of Group Tax         Reuters Group PLC
                                     85 Fleet Street
                                     London

       Robert Beynon                 Instinet Group, Inc.
                                     3 Times Square
                                     New York
                                     NY 10036, USA

       Mark Higgins                  Instinet Holdings Limited
                                     85 Fleet Street
                                     London

         PROVIDED THAT a party may change its notice details on giving notice to
         the other parties of the change in accordance with this clause. That
         notice shall only be effective on the day
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         falling five clear days after the notification has been received or
         such later date as may be specified in the notice.

19.3     Any notice given under this Agreement shall, in the absence of earlier
         receipt, be deemed to have been duly given as follows:-

         (i)      if delivered personally, on delivery;

         (ii)     if sent by first class post, three clear days after the date
                  of posting;

         (iii)    if sent by air mail, six clear days after the date of posting;
                  and

         (iv)     if sent by facsimile, provided telephonic confirmation of
                  receipt is obtained promptly, after completion of
                  transmission.

19.4     Any notice given under this Agreement outside normal business hours in
         the place to which it is addressed shall be deemed not to have been
         given until the start of the next period of normal business hours in
         such place.

20.      CONFIDENTIALITY.

20.1     Each party shall treat as confidential all information obtained as a
         result of entering into or performing this Agreement which relates to:-

         (i)      the provisions of this Agreement;

         (ii)     the negotiations relating to this Agreement;

         (iii)    the subject matter of this Agreement; and

         (iv)     any other party.

20.2     Notwithstanding the other provisions of this clause, any party may
         disclose confidential information:-

         (i)      if and to the extent required by law;

         (ii)     if and to the extent required by existing contractual
                  obligations;

         (iii)    if and to the extent required by any securities exchange or
                  regulatory or governmental body to which
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                  that party is subject, wherever situated, including (amongst
                  other bodies) the UK Listing Authority, the London Stock
                  Exchange or the Panel, whether or not the requirement for
                  information has the force of law;

         (iv)     if and to the extent required for the purposes of any
                  arbitration pursuant to clause 27.4;

         (v)      if and to the extent required to vest the full benefit of this
                  Agreement in that party;

         (vi)     to its professional advisers, auditors and bankers PROVIDED
                  THAT any such party is made subject to the same obligation as
                  to confidentiality in respect of the information which is the
                  subject of this Agreement;

         (vii)    if and to the extent the information has come into the public
                  domain through no fault of that party; or

         (viii)   if and to the extent the other parties have given prior
                  written consent to the disclosure, such consent not to be
                  unreasonably withheld or delayed.

         Any information to be disclosed pursuant to sub-clauses 20.2(ii),
         (iii), (v), (vi) or (vii) shall be disclosed only after prior written
         approval of the other parties.

20.3     The restrictions contained in this clause shall apply without limit in
         time.

21.      COUNTERPARTS.

21.1     This Agreement may be executed in two or more counterparts, and by the
         parties on separate counterparts, but shall not be effective until each
         party has executed at least one counterpart.

21.2     Each counterpart shall constitute an original of this Agreement, but
         all the counterparts shall together constitute but one and the same
         instrument.

22.      INVALIDITY.

22.1     If at any time any provision of this Agreement is or becomes illegal,
         invalid or unenforceable in any respect under the law of any
         jurisdiction, that shall not affect or impair:-
<PAGE>   19
                                       18


         (i)      the legality, validity or enforceability in that jurisdiction
                  of any other provision of this Agreement;

         (ii)     the legality, validity or enforceability under the law of any
                  other jurisdiction of that or any other provision of this
                  Agreement.

22.2     In the event that any provision of this Agreement shall be void or
         unenforceable by reason of any provision or applicable law, it shall be
         deleted and the remaining provisions hereof shall continue in full
         force and effect and, if necessary, be so amended as shall be necessary
         to give effect to the spirit of this Agreement so far as possible.

23.      LANGUAGE.

23.1     Each notice, demand, request, statement, instrument, certificate or
         other communication under or in connection with this Agreement shall
         be:-

         (i)      in English; or

         (ii)     if not in English, accompanied by an English translation made
                  by a translator, and certified by an officer of the party
                  giving the notice to be accurate.

23.2     The receiving party shall be entitled to assume the accuracy of and
         rely upon any English translation of any document provided.

24.      HEADINGS ETC.

         The headings and table of contents in this Agreement are for ease of
         reference only and shall not affect the construction hereof.

25.      THIRD PARTY RIGHTS.

         Pursuant to section 1(2) of the Contracts (Rights of Third Parties) Act
         1999 (the "Contracts Act") the parties intend that a person who is not
         a party to this Agreement has no right under the Contracts Act to
         enforce any term of this Agreement but this does not affect any right
         or remedy of a third party which exists or is available apart from the
         Contracts Act.

26.      CHOICE OF GOVERNING LAW AND JURISDICTION.
<PAGE>   20
                                       19


26.1     This Agreement shall be construed in accordance with, and governed in
         all respects by, English law.

26.2     The Courts of England shall have exclusive jurisdiction to entertain
         all disputes arising under or in relation to this Agreement.

27.      DISPUTE RESOLUTION.

27.1     If a dispute or difference arises out of this Agreement, the parties
         will attempt to settle it first by negotiation between themselves and
         then by mediation in accordance with the Centre for Dispute Resolution
         (CEDR) Model Mediation Procedure (the "Model Procedure"). To initiate a
         mediation, a party (the "Disputing Party") shall give notice in writing
         ("ADR Notice") to the other party (the "Non-Disputing Party"),
         requesting mediation in accordance with the provisions of the Model
         Procedure. A copy of the ADR Notice should also be sent to CEDR.

27.2     If such dispute or difference is not resolved within 42 days (or such
         longer period as the parties may agree) of the giving of the ADR
         Notice, or if one of the parties refuses to participate in mediation,
         the dispute shall be referred to arbitration in accordance with the
         provisions of clause 27.4.

27.3     Any unresolved dispute or difference arising out of or in connection
         with this Agreement, including any question regarding its existence,
         validity or termination, shall be referred to and finally resolved by
         arbitration.

27.4     Any dispute arising out of or in connection with this Agreement which
         remains unresolved after mediation, including any question regarding
         its existence, validity or termination, shall be referred to and
         finally resolved by arbitration under the rules of the London Court of
         International Arbitration ("LCIA"), which rules are deemed to be
         incorporated by reference into this clause.

27.5     If an ADR Notice is not given prior to the commencement of arbitration,
         the Disputing Party commencing the arbitration must serve an ADR Notice
         on the Non-Disputing Party to the arbitration within 21 days.

28.      AGENT FOR SERVICE.
<PAGE>   21
                                       20


28.1     LLC irrevocably appoints the European Tax Manager at Instinet Holdings
         Limited of 85 Fleet Street, London to be its agent for the receipt of
         Service Documents. LLC agrees that any Service Document may be
         effectively served on it in connection with proceedings in England and
         Wales by service on its agent effected in any manner permitted by the
         Civil Procedure Rules.

28.2     If the agent at any time ceases for any reason to act as such, LLC
         shall appoint a replacement agent having an address for service in
         England and shall notify Reuters of the name and address of the
         replacement agent. Failing such appointment and notification, Reuters
         shall be entitled by notice to LLC to appoint a replacement agent to
         act on behalf of LLC. The provisions of this clause applying to service
         on an agent apply equally to service on a replacement agent.

28.3     A copy of any Service Document served on an agent shall be sent by post
         to LLC. Failure or delay in so doing shall not prejudice the
         effectiveness of service of the Service Document.

28.4     "Service Document" means a claim form, application notice, order or
         judgment or other document relating to any proceedings.

29.      EXCLUSION.

         This Agreement shall not confer any benefit on a continuing Reuters
         company (other than Reuters) if it ceases to be controlled by Reuters.
         For the purposes of this clause a company shall cease to be controlled
         by Reuters if less than 51 per cent. of its ordinary share capital is
         owned (whether directly or indirectly) by Reuters.

30.      DURATION.

         This Agreement shall terminate and cease to confer any benefit on a
         continuing Reuters company if Reuters' holding (whether directly or
         indirectly) in the ordinary share capital of LLC (or any other
         successor entity which shall own Holdings, or any Instinet
         International Companies) falls either below (i) 40 per cent. for the
         purposes of the CFC provisions; or (ii) 50 per cent. in any other case.

IN WITNESS whereof the parties have executed this Agreement on the date and year
first above written.
<PAGE>   22
                                       21


Signed by REUTERS GROUP PLC acting
by its director
                                        ........................................
                                        Signature of Director

                                        ........................................
                                        Name of Director

Signed by INSTINET GROUP, INC (as
successor to INSTINET GROUP LLC)
acting by its officer.
                                        ........................................
                                        Signature of Officer

                                        ........................................
                                        Name of Officer

Signed by INSTINET HOLDINGS LIMITED
acting by its officer.                  ........................................
                                        Signature of Officer

                                        ........................................
                                        Name of Officer