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                                                                  Exhibit 10.37



                                                                        27-10-00


                       TESTING AND CERTIFICATION AGREEMENT

Date: November 7, 2000

1)    Instinet UK Limited ("Instinet") of Commodity Quay, East Smithfield,
      London E1W 1AZ

      and

2)    Effix SA ("Vendor") of 6 rue Godefroy, F-92821 Puteaux, Cedex, France


BACKGROUND

(A) Vendor has developed, on behalf of the Reuters Group, the software and/or
system(s) more fully described in Exhibit A attached hereto and made a part
hereof (the "Vendor Product(s)"); and

(B) Instinet has created, and provided to Vendor for evaluation, specifications
using the Financial Information Exchange ("FIX") protocol for the development or
enabling of access to the Instinet System (the "Fix Specifications") for
delivery by Instinet of the securities order entry and trade reporting services
described in the Specifications (the "Instinet Services") to mutual clients of
Reuters and Instinet; and

(C) Instinet and Vendor agree that Vendor may integrate Instinet's proprietary
OpenInstinet application, ("OpenInstinet") as more fully described in the
specification dated January 15, 2000, (the "OpenInstinet BookMark
Specification"); and

(D) Instinet is willing to grant Vendor a limited license to use the
OpenInstinet BookMark Specification for the sole purpose of integrating
OpenInstinet into the Vendor Products and a limited license to use the FIX
Specification for the sole purpose of testing and certifying the integration of
the Vendor product with the Instinet System to allow mutual clients of Instinet
and Reuters to access Instinet Services through the Vendor Product(s), all
subject to the terms and conditions contained in this Agreement;


AGREEMENT

1.    VENDOR'S GENERAL OBLIGATIONS.

      1.1   Development, Integration and Testing. Vendor shall provide the
      ability to access the Instinet Services and OpenInstinet via the Vendor's
      Product(s) and shall test the Vendor Product(s) to ensure that such access
      operates in accordance with, and conforms to the Fix Specification and
      OpenInstinet Specification (jointly, the "Specifications").
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      Vendor shall be solely responsible for any and all costs and expenses
      incurred in the development, testing and installation of the Vendor
      Product(s). The Vendor Product(s), except for OpenInstinet, are and shall
      remain the property of Vendor.

      1.2   Acceptance. Upon completion of Vendor's testing pursuant to Section
      1.1 of this Agreement, Vendor shall test the Vendor Product(s) with
      Instinet (the "Acceptance Testing") until Instinet, in its sole
      discretion, has certified the Vendor Product(s) for connection to the
      Instinet System and provision of the Instinet Services and OpenInstinet
      via the Vendor Product(s) to customers, ("Acceptance").

      1.3   Upgrades and Alterations.

      1.3.1 Vendor. Vendor shall notify Instinet in writing as promptly as
      practicable prior to the release of any upgrade or alteration to the
      Vendor Product(s) that would affect the architecture of the Vendor
      Product(s) as it pertains to any order directed to Instinet by mutual
      clients of Reuters and Instinet (the "Customer Orders"), the Instinet
      Services and/or OpenInstinet. In the event any upgrade or modification to
      the Vendor Product(s) causes any harm to Instinet or interferes in any way
      with Customer Orders, the Instinet System, the Instinet Services, and/or
      OpenInstinet Vendor shall either promptly (i) rectify the harm or (ii)
      revert to the previously certified version of the Vendor Product(s) at
      Instinet's request. Instinet shall have the right to perform Acceptance
      Testing, in accordance with Section 1.2 herein, on all upgrades or
      modifications of the Vendor Product(s) which pertain to Customer Orders,
      the Instinet System, the Instinet Services and/or OpenInstinet, prior to
      release of any such upgrade or modification.

      1.3.2 Instinet. Instinet may upgrade and/or alter the Specifications, in
      its sole discretion, from time to time during the term of this Agreement.
      Instinet shall notify Vendor of such upgrade and/or alteration and provide
      to Vendor revised Specifications reflecting such upgrade and/or alteration
      (the "Revised Specifications") as promptly as practicable.

      1.4   Support Services and Training. Vendor shall make available a
      commercially reasonable number of personnel expertly trained to respond to
      questions from Instinet regarding the Vendor's Product(s) as pertaining to
      Customer Orders, the Instinet System, the Instinet Services and/or
      OpenInstinet during Vendor's normal business hours

      1.5   Access Parity. Vendor shall ensure that the Vendor Product(s)
      provides access to Instinet Services and OpenInstinet in a manner that is
      at least as favourable, both with respect to the time required to access
      the Instinet Services and the mechanics by which the Instinet Services and
      OpenInstinet are accessed, as the manner in which the Vendor Product(s)
      provide such access to the services of any other broker-dealer, Electronic
      Communication Network ("ECN") or other order entry or trade reporting
      service or destination. In the event that Vendor becomes aware (through
      notice from Instinet, a customer or otherwise) that access to Instinet
      Services is not available in accordance with the foregoing sentence,
      without limiting any remedies available under this


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      Agreement or otherwise under law, Vendor shall use its best efforts to
      make such access to Instinet Services compliant with the foregoing
      sentence.

      Notwithstanding the foregoing, nothing herein shall prevent Vendor from
      entering into any strategic business alliance with any broker-dealer, ECN
      or other order entry or trade reporting service or destination where the
      specific terms and conditions of such alliance require Vendor to provide
      access to the counterparty's destination in a manner that is more
      favourable than the access Vendor provides to other destinations,
      including the Instinet Services.

      1.6   Order Handling. Vendor shall not do anything that would prevent the
      Customer Orders being routed to Instinet in accordance with the
      Specifications and identified to Instinet as the orders of the customers
      from whom they originate. In no event shall Vendor allow the vendor
      product or its integration to (i) redirect Customer Orders to any other
      ECN, order entry system or any other destination, (ii) conglomerate or
      aggregate Customer Orders with other Customer Orders or any other orders
      whatsoever, (iii) use any information derived from the Customer Orders for
      any purposes other than the fulfillment of its obligations under this
      Agreement (iv) match or otherwise fill Customer Orders, or (v) take any
      action that would compromise the anonymity of a Customer Order.

      1.7   Instinet Branding. Vendor shall ensure that all access to the
      Instinet Services through the Vendor Product(s) are clearly labeled as
      connecting to Instinet ("Instinet Branding"). The Instinet Branding for
      the Vendor Product(s) and/or any upgrade or modification thereto shall be
      mutually agreed by Vendor and Instinet.


2.    CONFIDENTIALITY.

      2.1   Provision of Confidential Matter. During the term of this Agreement,
      the Parties shall provide and/or disclose to each other certain
      information, which may be written or oral, that the Parties, their
      respective affiliates or their customers deem confidential and
      proprietary, whether or not such information is labeled as confidential or
      proprietary at the time it is provided or disclosed ("Confidential
      Matter"). Confidential Matter also shall include information relating to
      third party vendors or information that is proprietary to the disclosing
      Party's customers or affiliates. (The Party providing Confidential Matter
      is referred to in this Section 2 as the "Providing Party," and the Party
      receiving Confidential Matter is referred to in this Section 2 as the
      "Receiving Party").

      For purposes of this Agreement, Confidential Matter shall not include (a)
      information that was in the Receiving Party's possession, without
      restriction, prior to its disclosure to the Receiving Party by the
      Providing Party, (b) information that lawfully enters the public domain
      without violation of this Section 2 by the Receiving Party, (c)
      information that the Receiving Party lawfully receives from a third party
      without restriction and without


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      violation of any duty of confidentiality owed to the Providing Party, and
      (d) information that is independently developed by the Receiving Party.

      2.2   Non-Disclosure. Except (i) as set forth in Section 2.4, and (ii) as
      may be required by law or any regulatory body or court (but only after
      compliance with Section 2.6) the Receiving Party shall maintain as
      confidential and shall not disclose Confidential Matter in whole or in
      part, directly or indirectly, to any other individual, firm, corporation
      or government authority.

      2.3   Use of Confidential Matter. Following the receipt of Confidential
      Matter, the Receiving Party shall (i) use at least the same degree of
      care, but in no event less than reasonable care, to protect such
      Confidential Matter as the Receiving Party uses with respect to its own
      confidential and proprietary information; and (ii) use such Confidential
      Matter only to fulfill its obligations under this Agreement and only in
      accordance with the terms and conditions of this Agreement.

      2.4   Representatives of the Receiving Party. Notwithstanding the
      restrictions set forth in Section 2.2, the Receiving Party may furnish the
      Confidential Matter to any of its directors, officers and employees
      (collectively, "Representatives") who need to know such information for
      the purposes set forth in Section 2.3; provided, however, that such
      Representatives are instructed to keep such information confidential in
      accordance with this Section 2. The Receiving Party shall be responsible
      for any breach of this Section 2 by any of its Representatives and agrees,
      at its sole expense, to take all reasonable measures (including but not
      limited to court proceedings) to restrain its Representatives from
      prohibited or unauthorised disclosure or use of any Confidential Matter.

      2.5   No Other Rights. Nothing contained in this Section 2 shall be
      construed as granting or conferring any rights by license or otherwise to
      the Receiving Party in any Providing Party's Confidential Matter.

      2.6   Required Disclosure. If a Receiving Party is requested or required
      in any judicial or administrative proceeding or by any regulatory body or
      court to disclose any Confidential Matter, such Receiving Party shall (i)
      use its best efforts to give the Providing Party prompt notice of such
      request so that it may seek an appropriate protective order or other
      remedy and (ii) consult with the Providing Party as to the advisability of
      taking legally available steps to resist or narrow such request or
      requirement. The Receiving Party shall cooperate fully with the Providing
      Party in obtaining such an order or other remedy. If in the absence of an
      appropriate protective order or other remedy the Receiving Party is
      nonetheless legally required to disclose Confidential Matter, the
      Receiving Party may make such disclosure without liability hereunder;
      provided, however, that the Receiving Party shall use its best efforts to
      give the Providing Party written notice of the information to be disclosed
      as far in advance of its disclosure as is practicable and, upon the
      Providing Party's request and at its expense, use its best efforts to
      obtain reasonable assurances that confidential treatment will be accorded
      to such Confidential Matter.

      2.7   NOTWITHSTANDING THE FOREGOING, VENDOR IS EXPRESSLY PROHIBITED FROM
      RELEASING THE IDENTITY OF ANY AUTHORISED CUSTOMER TO ANY OTHER AUTHORISED
      CUSTOMER OR THIRD PARTY


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      WITHOUT FIRST OBTAINING THE WRITTEN CONSENT OF SUCH AUTHORISED CUSTOMER
      AND PROVIDING A COPY THEREOF TO INSTINET.


3.    REPRESENTATIONS AND WARRANTIES.

      3.1   Vendor Representations, Warranties and Covenants. Vendor represents,
      warrants and covenants to Instinet that:

      3.1.1 the execution and delivery by Vendor of this Agreement and the
      performance of its obligations hereunder have been Authorised by all
      necessary action, corporate and otherwise, and that this Agreement
      constitutes a legal, valid and binding obligation of Vendor enforceable in
      accordance with its terms, except to the extent that such enforceability
      is subject to or limited by bankruptcy, insolvency or similar laws
      relating to the enforcement of creditor's rights;

      3.1.2 the execution and delivery by Vendor of this Agreement and the
      performance of its obligations hereunder does not breach any law, rules or
      regulations to which Vendor is subject or any agreement, obligation or
      restriction by which Vendor is bound, and Vendor will not enter into or
      assume any agreement, obligation or restriction that will interfere with
      any of its obligations hereunder or the rights granted herein.

      3.2   Instinet Representations, Warranties and Covenants. Instinet
      represents, warrants and covenants to Vendor that:

      3.2.1. the execution and delivery by Instinet of this Agreement and the
      performance of its obligations hereunder have been Authorised by all
      necessary action, corporate and otherwise, and this Agreement constitutes
      a legal, valid and binding obligation of Instinet enforceable in
      accordance with its terms, except to the extent that such enforceability
      is subject to or limited by bankruptcy, insolvency or similar laws
      relating to the enforcement of creditor's rights;

      3.2.2 the execution and delivery by Instinet of this Agreement and the
      performance of its obligations hereunder does not breach any law, rules or
      regulations to which Instinet is subject or any agreement, obligation or
      restriction by which Instinet is bound and Instinet will not enter into or
      assume any agreement, obligation or restriction that will interfere with
      any of its obligations hereunder or the rights granted herein; and

      3.2.3 Instinet has the right and authority to grant the license to the
      Specifications.

4.    DISCLAIMER OF WARRANTIES AND LIMITATION OF LIABILITY.  EXCEPT AS SET
      FORTH IN SECTION 3.1 OF THIS AGREEMENT WITH RESPECT TO VENDOR, AND
      SECTION 3.2 OF THIS AGREEMENT WITH RESPECT TO INSTINET, (I) THE VENDOR
      PRODUCT(S), WITH RESPECT TO VENDOR, AND (II) THE SPECIFICATIONS AND
      INSTINET SERVICES, WITH RESPECT TO INSTINET, ARE PROVIDED "AS IS"
      WITHOUT WARRANTY OF ANY KIND BY


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      VENDOR OR INSTINET, RESPECTIVELY, INCLUDING BUT NOT LIMITED TO ANY IMPLIED
      WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. EXCEPT
      WITH RESPECT TO THE INDEMNIFICATION OBLIGATIONS CONTAINED IN SECTION 5 OF
      THIS AGREEMENT OR ANY INTENTIONAL MATERIAL BREACH OF THE CONFIDENTIALITY
      OBLIGATIONS CONTAINED IN SECTION 2 OF THIS AGREEMENT, NEITHER PARTY SHALL
      BE LIABLE TO THE OTHER OR ANY THIRD PARTY CLAIMING THROUGH THE OTHER, FOR
      ANY SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
      FURNISHING, PERFORMANCE, OR USE OF, OR INABILITY TO USE, THE
      SPECIFICATIONS, THE VENDOR PRODUCTS(S) OR THE INSTINET SERVICES PROVIDED
      UNDER THIS AGREEMENT.

5.    INDEMNIFICATION

      5.1   Vendor Indemnification of Instinet. Subject to the limitations set
      forth in this Section 5.1, Vendor, at its own expense, shall: (i)
      indemnify, defend and hold Instinet and/or any of its affiliates and its
      or their respective officers, directors, partners, employees, agents or
      representatives (collectively, the "Instinet Indemnitees"), harmless from
      and against (or at its option, but with Instinet's prior agreement,
      settle) any claim, action, suit or proceeding against Instinet or any of
      its affiliates and any of their respective officers, directors, partners,
      employees, agents and representatives on the basis of (A) any alleged
      infringement in whole or in part, of any third party's patent, copyright,
      trade secret or other intellectual property rights by the Vendor
      Product(s), and (B) any breach by Vendor of the obligations in Sections
      1.5, 1.6, 1.7, or the representations, warranties or covenants set forth
      in Section 3.1 of this Agreement; (ii) pay any final judgment entered or
      settlement against Instinet and indemnify and defend and hold Instinet
      harmless from and against all damages, liabilities, costs and expenses
      incurred by Instinet arising out of or in connection with any such claim,
      action, suit or proceeding. Vendor shall have no obligation to any of the
      Instinet Indemnitees pursuant to this Section 5.1 unless: (A) Instinet
      provides Vendor prompt written notice of the claim, action, suit or
      proceeding after Instinet's discovery thereof; (B) Vendor is given the
      right to control and direct the investigation, preparation, defense and
      settlement of the claim, action, suit or proceeding; provided, however,
      that Instinet shall retain the right to file an answer or take any other
      action necessary to prevent the entry of a default judgment or injunction
      against it and the right to consult with Vendor regarding the litigation
      or settlement; and (C) Instinet gives Vendor reasonable assistance and
      information at Instinet's expense in connection with such claim, action,
      suit or proceeding.

      5.2   Instinet Indemnification of Vendor. Subject to the limitations set
      forth in this Section 5.2, Instinet, at its own expense, shall: (i)
      indemnify, defend and hold Vendor and/or any of its affiliates and its or
      their respective officers, directors, partners, employees, agents or
      representatives (collectively, the "Vendor Indemnitees"), harmless from
      and against (or at its option, but with Vendor's prior agreement, settle)
      any claim, action, suit or proceeding against Vendor or any of its
      affiliates and any of their respective officers, directors, partners,
      employees, agents and representatives on the basis


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      of (A) any alleged infringement in whole or in part, of any third party's
      intellectual property rights by the Specifications (unless such
      Specifications are jointly developed by Instinet and Vendor) (B) the
      Instinet Services (unless such Instinet Services are modified or altered
      by Vendor); and (C) any breach by Instinet of the representations,
      warranties or covenants set forth in Section 3.2 of this Agreement; and
      (ii) pay any final judgment entered or settlement against Vendor and
      indemnify and defend and hold Vendor harmless from and against all
      damages, liabilities, costs and expenses incurred by Vendor arising out of
      or in connection with any such claim, action, suit or proceeding. Instinet
      shall have no obligation to any of the Vendor Indemnitees pursuant to this
      Section 5.2 unless: (A) Vendor provides Instinet prompt written notice of
      the claim, action, suit or proceeding after Vendor's discovery thereof;
      (B) Instinet is given the right to control and direct the investigation,
      preparation, defense and settlement of the claim, action, suit or
      proceeding; provided, however, that Vendor shall retain the right to file
      an answer or take any other action necessary to prevent the entry of a
      default judgment or injunction against it and the right to consult with
      Instinet regarding the litigation or settlement; and (C) Vendor gives
      Instinet reasonable assistance and information at Vendor's expense in
      connection with such claim, action, suit or proceeding.

6.    TERM, TERMINATION, EFFECT OF TERMINATION AND SURVIVAL.

      6.1   Term. This Agreement shall be deemed effective as of 25th April 2000
      and shall remain in effect until terminated by either Party pursuant to
      this Section 6.

      6.2   Termination.

      6.2.1 Termination by Instinet. Instinet may terminate this Agreement and
      the limited license granted hereunder in its sole discretion, at any time,
      with or without cause, by giving thirty (30) days' prior written notice to
      Vendor. Instinet may terminate this Agreement and the limited license
      granted hereunder without prior notice, effective immediately, in the
      event that (A) Vendor commits a material breach of its obligations under
      this Agreement, (B) Instinet determines that the continued provision of
      the Instinet Services via the Vendor Product(s) would be detrimental to
      Instinet or any of its customers, or (C) Vendor fails to meet its
      obligations under Section 1.5, 1.6, 1.7 hereof.

      6.2.2 Termination by Vendor. Vendor may terminate this Agreement and the
      limited license granted hereunder (i) in its sole discretion, with or
      without cause, upon 30 days' prior written notice, or (ii) without prior
      notice, effective immediately, in the event Instinet commits a material
      breach of its obligations under this Agreement.

      6.3   Effect of Termination and Survival.

      6.3.1 Instinet and Vendor. Upon termination of this Agreement pursuant to
      this Section 8, the Parties shall promptly return to the other Party any
      tangible Confidential Matter in its possession, purge all Confidential
      Matter from its electronic records, and immediately


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      cease all marketing efforts, including any use of the other Party's name,
      trademark, service mark or logo.

      6.3.2 Survival. Sections 2, 4, 5, and 7.6 of this Agreement shall survive
      any termination of this Agreement for any reason.

7.    MISCELLANEOUS.

      7.1   Equitable Relief. The Parties agree that the remedy at law for any
      breach by either Party of the terms of Sections 2 and 1.7hereof will be
      inadequate and that, accordingly, in addition to any remedies either Party
      may have at law, both Parties will be entitled to apply for and obtain
      equitable relief in any court of competent jurisdiction to restrain the
      breach or threatened breach of, or otherwise to specifically enforce such
      terms.

      7.2   Notices. All notices which are required to be given pursuant to this
      Agreement shall be in writing and shall be hand delivered, sent by
      overnight courier (such as Federal Express), or sent by facsimile
      transmission, with a confirming copy sent by first class mail, postpaid,
      or sent by registered or certified mail, return receipt requested, to the
      following address or to such other address as a Party may from time to
      time designate by notice. Such notices shall be deemed given upon receipt
      if hand delivered, on the next business day if sent by overnight courier,
      upon receipt of a confirmation of transmission if sent via facsimile or
      three (3) business days after mailing if sent via registered or certified
      mail:

      If to Instinet:                     Commodity Quay,
                                          East Smithfield
                                          London E1W 1AZ
                        Attention:        Ruth Liggett

                        With a copy to:   Address as above
                        Attention:        European General Counsel


      If to Vendor:                       6, rue Godefroy
                                          92821 PUTEAUX CEDEX
                                          FRANCE



      7.3   Entire Agreement and Amendment. This Agreement, including the
      Exhibits, if any, contains the entire agreement between the parties with
      respect to the subject matter hereof and supersedes all other prior or
      contemporaneous oral or written communications, proposals, agreements and
      representations with respect to the subject matter. No amendment or
      modification to this Agreement shall be binding, unless it is in writing
      and executed by each Party.



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      7.4   Assignment. This Agreement and the rights granted and obligations
      undertaken hereunder may not be transferred, assigned or delegated, by
      operation of law or otherwise, in any manner by Vendor.

      7.5   Waiver of Compliance and Severability. Any waiver of any provision
      of this Agreement, or any delay by either party in the enforcement of any
      right hereunder, shall neither be construed as a continuing waiver nor
      create an expectation of non-enforcement of that or any other provision or
      right. In the event any one or more of the provisions of this Agreement
      shall for any reason be held to be invalid, illegal or unenforceable, the
      remaining provisions of this Agreement shall be unimpaired, and the
      Parties shall negotiate in good faith to substitute a provision of like
      economic intent and effect.

      7.6   Governing Law and Choice of Forum. This Agreement is made under and
      shall be governed by and construed in accordance with the laws of England
      and Wales. Both parties consent to the jurisdiction of the courts of
      England and Wales, and agree to institute any and all actions relating to
      this Agreement in such courts.

      7.7   Interpretation. The section headings contained in this Agreement are
      solely for the purpose of reference, are not part of the agreement between
      the parties and shall not in any way affect the meaning or interpretation
      of this Agreement.

      7.8   Counterparts. This Agreement may be executed in one or more
      counterparts, each of which shall be deemed an original, and both of which
      together shall constitute one and the same instrument.

      IN WITNESS WHEREOF, the authorised officers of the parties hereto have
executed this Vendor Interface Agreement as of the date first written above.

EFFIX SA                                  INSTINET UK LIMITED


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



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EXHIBIT A

                        DESCRIPTION OF VENDOR PRODUCT(S)






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