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                                                                    EXHIBIT 2.10

                  CONTRIBUTION AND ASSUMPTION AGREEMENT, dated as of November
24, 2003, by and between Instinet Group Incorporated, a Delaware corporation
("IGI"), and Instinet Group, LLC, a Delaware limited liability company
("IGLLC").

                  WHEREAS, IGI and certain other direct and indirect
subsidiaries of IGI are engaging in an internal restructuring (the
"Restructuring") pursuant to resolutions of the Board of Directors of IGI dated
October 7, 2003;

                  WHEREAS, IGLLC is a wholly-owned subsidiary of IGI;

                  WHEREAS, as part of the Restructuring, IGI desires to
contribute to IGLLC as a contribution to capital, and IGLLC desires to acquire
from IGI, the assets listed on Schedule 1 hereto (the "Transferred Assets");

                  WHEREAS, in connection with the acquisition of the Transferred
Assets, ICorp also desires to transfer to IGLLC, and IGLLC desires to accept,
the employment of the employees listed on Schedule 2 (the "Transferred
Employees") to IGLLC;

                  NOW, THEREFORE, in consideration of the foregoing and the
respective premises, mutual covenants and agreements of IGI and IGLLC, and other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, and subject to the terms and conditions hereof, IGI and IGLLC
agree as follows:

                                   ARTICLE I

                                  DEFINITIONS

                  1.1. Definitions. For the purpose of this Agreement the
following terms shall have the following meanings:

                  "Action" means any demand, action, suit, countersuit,
arbitration, inquiry, proceeding or investigation by or before any federal,
state, local, foreign or international Authority or any arbitration or mediation
tribunal.

                  "Agreement" means this Contribution and Assumption Agreement,
including all of the Schedules hereto.

                  "Assumed Liabilities" has the meaning set forth in Section
2.3.

                  "Authority" means any governmental, judicial, legislative,
executive, administrative, or regulatory authority of the United States, or of
any state, local or foreign government, or any government of any possession or
territory of the United States, or any subdivision, agency, commission, office
or authority of any of the foregoing, or any Self-Regulatory Organization.

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                  "Consents" means any consents, waivers, approvals or
authorizations from, or notification requirements to, any third parties or any
Authority or any reports or other filings to be made to, or registrations or
permits or authorizations to be obtained from, any Authority.

                  "Effective Time" means 1:25 AM EST, December 1, 2003.

                  "IGI" has the meaning set forth in the preamble.

                  "IGLLC" has the meaning set forth in the preamble.

                  "Indemnified Party" has the meaning set forth in Section
4.4(a).

                  "Indemnifying Party" has the meaning set forth in Section
4.4(a).

                  "Instinet" has the meaning set forth in the recitals.

                  "Liabilities" means any and all losses, claims, charges,
debts, demands, Actions, causes of action, suits, damages, obligations,
payments, costs and expenses, sums of money, accounts, reckonings, indemnities,
and similar obligations, exonerations, covenants, contracts, controversies,
agreements, promises, doings, omissions, variances, guarantees, make whole
agreements and similar obligations, and other liabilities, including all
contractual obligations, whether absolute or contingent, matured or unmatured,
liquidated or unliquidated, accrued or unaccrued, known or unknown, whenever
arising, and including those arising under any law, rule, regulation, Action,
threatened or contemplated Action (including the costs and expenses of demands,
assessments, judgments, settlements and compromises relating thereto and
attorneys' fees and any and all costs and expenses whatsoever reasonably
incurred in investigating, preparing or defending against any such Actions or
threatened or contemplated Actions), order or consent decree of any Authority or
any award of any arbitrator or mediator of any kind, and those arising under any
contract, commitment or undertaking, including those arising under this
Agreement, whether or not recorded or reflected or required to be recorded or
reflected on the books and records or financial statements of any Person.

                  "Person" means an individual, a general or limited
partnership, a corporation, a trust, a joint venture, an unincorporated
organization, a limited liability entity, any other entity and any Authority.

                  "Restructuring" has the meaning set forth in the recitals.

                  "Self Regulatory Organization" has the meaning set forth in
section 3(a)(26) of the Securities Exchange Act of 1934, and the rules and
regulations promulgated thereunder, as amended.

                  "Transferred Assets" has the meaning set forth in the
recitals.

                  "Transferred Employees" has the meaning set forth in the
recitals.

                  1.2. Interpretation. In this Agreement and in the Schedules
hereto:

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                  (a)      unless otherwise specified, references to Articles,
Sections, clauses and Schedules are references to Articles, Sections and clauses
of, and Schedules to, this Agreement;

                  (b)      the headings in this Agreement are for reference only
and shall not control or affect the meaning or construction of any of the
provisions hereof;

                  (c)      references to any document or agreement, including
this Agreement, shall be deemed to include references to such document or
agreement as amended, supplemented or replaced from time to time in accordance
with its terms and (where applicable) subject to compliance with the
requirements set forth therein; and

                  (d)      references to any party to this Agreement or any
other document or agreement shall include its successors and permitted assigns.

                                   ARTICLE II

                TRANSFER OF ASSETS AND ASSUMPTION OF LIABILITIES

                  2.1. Transfer of Assets and Assumption of Liabilities. Subject
to the receipt of all Consents, approvals or authorizations of any Authority, or
any other Person, necessary to consummate the transactions contemplated herein,
upon the terms and subject to the conditions set forth in this Agreement, as of
the Effective Time, (a) IGI shall hereby contribute, assign, transfer, convey
and deliver to IGLLC on an as-is, where-is basis, and IGLLC shall hereby accept
from IGI, all of IGI's right, title and interest in and to the Transferred
Assets and (b) IGLLC shall hereby assume and agree faithfully to perform and
fulfill all the Assumed Liabilities in accordance with their respective terms.

                  2.2 Transfer of Employees. As of the Effective Time, IGI shall
hereby transfer to IGLLC, and IGLLC shall hereby accept, the employment of the
Transferred Employees. For the avoidance of doubt, the transfer of employment of
the Transferred Employees shall not constitute a termination of employment for
purposes of any compensation or benefit plan, program, policy, agreement or
other arrangement and, after the Effective Time, subject to the terms of any
agreement between any Transferred Employee, on the one hand, and IGLLC and its
affiliates, on the other hand, the employment of any such Transferred Employees
shall be at-will and terminable at any time for any or no reason whatsoever.

                  2.3. Assumed Liabilities. "Assumed Liabilities" shall mean all
of the Liabilities relating to or arising out of the Transferred Assets and
Transferred Employees, and business activity related to such Transferred Assets
and Transferred Employees, from and after the Effective Time.

                                   ARTICLE III

                                    COVENANTS

                  3.1. Documents Relating to Transfers of Assets and Assumption
of Liabilities. In furtherance of the contribution, assignment, transfer and
conveyance of the Transferred Assets,

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the transfer of employment of the Transferred Employees and the assumption of
the Assumed Liabilities as set forth in Sections 2.1 and 2.2, as of the
Effective Time, (a) IGI shall execute and deliver such bills of sale,
certificates of title, assignments of contracts and other instruments of
transfer, conveyance and assignment as and to the extent necessary to evidence
the contribution, transfer, conveyance and assignment of all of IGI's right,
title and interest in and to the Transferred Assets to IGLLC and the transfer of
employment of the Transferred Employees, and (b) IGLLC shall execute and deliver
to IGI such bills of sale, certificates of title, assumptions of contracts and
other instruments of assumption as and to the extent necessary to evidence the
valid and effective contribution, transfer, conveyance and assignment of the
Transferred Assets and the transfer of employment of the Transferred Employees
to, and assumption of the Assumed Liabilities by, IGLLC.

                  3.2. Further Assurances. (a) In addition to the actions
specifically provided for elsewhere in this Agreement, each party shall use its
reasonable best efforts from the date hereof to take, or cause to be taken, all
actions, and to do, or cause to be done, all things, reasonably necessary,
proper or advisable under applicable laws, regulations and agreements to
consummate and make effective the transactions contemplated by this Agreement.

                  (b)      Without limiting the foregoing, on and after the date
hereof, each party shall cooperate with the other party, and without any further
consideration, to execute and deliver, or use its reasonable best efforts to
cause to be executed and delivered, all instruments, including instruments of
conveyance, assignment and transfer, and to make all filings with any Authority,
and to obtain all Consents under any permit, license, agreement, indenture or
other instrument, and to take all such other actions as such party may
reasonably be requested by the other party from time to time, consistent with
the terms of this Agreement in order to effectuate the provisions and purposes
of this Agreement and the transfer of the Transferred Assets, the transfer of
employment of the Transferred Employees, and the assignment and assumption of
the Assumed Liabilities and the other transactions contemplated hereby. Without
limiting the foregoing, each party will, at the reasonable request of the other
party, take such other actions as may be reasonably necessary to vest in such
other party good and marketable title to the Transferred Assets if and to the
extent it is practicable to do so.

                  3.3. Delayed Transfers. To the extent that any Transferred
Asset or Assumed Liability that would otherwise be assigned to, or assumed by,
IGLLC at the Effective Time pursuant to Section 2.1 is not capable of being
assigned or assumed without obtaining a Consent, which Consent has not been
received on or prior to the Effective Time, any such Transferred Asset or
Assumed Liability will be assigned or assumed on the date the requisite Consent
is received and until such time, IGI shall be deemed to have assigned to IGLLC
hereby the economic benefit received by IGI from and after the Effective Time
with respect to the applicable rights and/or interests under such Transferred
Assets and shall hold such Transferred Asset in trust for IGLLC, and IGLLC shall
have been deemed to have assumed the economic detriment incurred by IGI from and
after the Effective Time with respect to the Assumed Liabilities, except to the
extent that any such deemed transfer or assumption itself requires a Consent,
which Consent has not been received on or prior to the Effective Time; provided
that in the event such Consent is not received prior to the first anniversary of
this Agreement, such Transferred Asset or Assumed Liability shall not be
assigned or assumed by IGLLC pursuant to

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the terms of this Agreement and shall be deemed not to be a Transferred Asset or
an Assumed Liability.

                                   ARTICLE IV

                                 INDEMNIFICATION

                  4.1. Indemnification By IGLLC. IGLLC shall indemnify, defend
and hold harmless IGI and its directors, officers and employees, and each of the
heirs, executors, successors and assigns of any of the foregoing, from and
against any and all Liabilities relating to, arising out of or resulting from
any of the following items (without duplication):

                  (a)      the failure of IGLLC or any other Person to pay,
perform or otherwise promptly discharge any Assumed Liability in accordance with
its terms, whether prior to or after the date hereof; and

                  (b)      the breach of any representation, warranty, covenant
or agreement by IGLLC contained in this Agreement.

                  4.2. Indemnification By IGI. IGI shall indemnify, defend and
hold harmless IGLLC and its directors, officers and employees, and each of the
heirs, executors, successors and assigns of any of the foregoing, from and
against any and all Liabilities relating to, arising out of or resulting from
the breach of any representation, warranty, covenant or agreement by IGI
contained in this Agreement.

                  4.3. Consequential Damages. Except as provided in the
following sentence, in no event shall any indemnity pursuant to Section 4.1 or
Section 4.2 include any incidental, consequential, indirect, special or punitive
damages. However, any indemnity pursuant to Section 4.1 or Section 4.2 shall
include any such incidental, consequential, indirect, special or punitive
damages recovered by any third party pursuant to a claim against an Indemnified
Party.

                  4.4. Defense of Claims. All rights of a party to
indemnification under this Article IV shall be asserted and resolved as follows:

                  (a)      Promptly after receipt by a party entitled to
indemnification under Section 4.1 or Section 4.2 (an "Indemnified Party") of
notice of any pending or threatened claim, such Indemnified Party shall give
notice to the party to whom the Indemnified Party is entitled to look for
indemnification (the "Indemnifying Party") of the commencement thereof; provided
that the failure so to notify the Indemnifying Party shall not relieve it of any
liability that it may have to the Indemnified Party hereunder, except to the
extent that the Indemnifying Party demonstrates that it is actually prejudiced
thereby.

                  (b)      In case any claim shall be brought against an
Indemnified Party and it shall give notice to the Indemnifying Party of the
commencement thereof, the Indemnifying Party shall be entitled to participate
therein and, if it so desires, to assume the defense thereof with counsel
reasonably satisfactory to the Indemnified Party and, after notice from the
Indemnifying Party to the Indemnified Party of its election to assume the
defense thereof, except as provided below, the Indemnifying Party shall not be
liable to such Indemnified Party under

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this Article IV for any fees of other counsel or any other expenses, in each
case subsequently incurred by such Indemnified Party in connection with the
defense thereof, other than reasonable out-of-pocket costs of investigation.
Notwithstanding an Indemnifying Party's election to assume the defense of a
claim, the Indemnified Party shall have the right to employ separate counsel and
to participate in the defense of such claim, and the Indemnifying Party shall
bear the reasonable fees, costs and expenses of such separate counsel, if (i)
the use of counsel chosen by the Indemnifying Party to represent the Indemnified
Party would present, in the advice of counsel, such counsel with a conflict of
interest, (ii) the actual or potential defendants in, or targets of, any such
claim include both the Indemnifying Party and the Indemnified Party, and the
Indemnified Party shall have reasonably concluded, upon the advice of counsel,
that there may be legal defenses available to it which are different from or
additional to those available to the Indemnifying Party (in which case the
Indemnifying Party shall not have the right to assume the defense of such claim
on the Indemnified Party's behalf), (iii) the Indemnifying Party shall not have
employed counsel reasonably satisfactory to the Indemnified Party to represent
the Indemnified Party within a reasonable time after notice of the institution
of such claim, or (iv) the Indemnifying Party shall authorize the Indemnified
Party to employ separate counsel at the Indemnifying Party's expense. If an
Indemnifying Party assumes the defense of a claim, no compromise or settlement
thereof may be effected by the Indemnifying Party without the Indemnified
Party's written consent unless (i) there is no finding or admission of any
violation of law and no effect or any other claims that may be made against the
Indemnified Party and (ii) the relief provided shall be paid in full or
otherwise satisfied by the Indemnifying Party.

                  (c)      In the event any Indemnified Party should have a
claim against any Indemnifying Party hereunder which does not involve a claim
being asserted by a third party, the Indemnified Party shall as promptly as is
practical notify the Indemnifying Party of such claim, describing such claim,
the amount thereof (if known) and the method of computation of the amount of the
claim, all with reasonable particularity. The failure to give any such notice
shall not relieve the Indemnifying Party of its obligations hereunder except to
the extent that such failure results in actual prejudice to the Indemnifying
Party. Upon the giving of such written notice as aforesaid, the Indemnified
Party shall have the right to commence legal proceedings for the enforcement of
its rights under Section 4.1 or Section 4.2.

                  4.5. Survival of Indemnities. The rights and obligations of
each party under this Article IV shall survive the closing of the transactions
contemplated hereby and the sale or other transfer by any party of any assets or
businesses or the assignment by it of any Liabilities.

                                   ARTICLE V

                                 MISCELLANEOUS

                  5.1. Counterparts; Entire Agreement; Corporate Power.

                  (a)      This Agreement may be executed in one or more
counterparts, all of which shall be considered one and the same agreement, and
shall become effective when one or more counterparts have been signed by each of
the parties and delivered to the other party.

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                  (b)      This Agreement and the Schedules hereto contain the
entire agreement between the parties with respect to the subject matter hereof
and supersede all previous agreements and understandings with respect to such
subject matter.

                  (c)      Each of IGI and IGLLC represents on behalf of itself
to the other as follows:

                           (i)      each such Person has the requisite corporate
         or other power and authority and has taken all corporate or other
         action necessary in order to execute, deliver and perform this
         Agreement and to consummate the transactions contemplated hereby; and

                           (ii)     this Agreement has been duly executed and
         delivered by it and constitutes a valid and binding agreement of it
         enforceable in accordance with the terms hereof, subject to bankruptcy,
         insolvency, fraudulent conveyance, reorganization, moratorium or other
         similar laws relating to the enforcement of creditors' rights generally
         and by general principles of equity.

                  5.2. Governing Law. This Agreement shall be construed in
accordance with and governed by the laws of the State of New York, irrespective
of the choice of laws principles of the State of New York.

                  5.3. Submission to Jurisdiction. Each party hereby irrevocably
agrees that any legal action or proceeding against it arising out of this
Agreement or the transactions contemplated hereby shall be brought only in the
State of New York in and for the County of New York or the U.S. District Court
for the Southern District of New York.

                  5.4. Assignability. This Agreement shall be binding upon and
inure to the benefit of the parties and their respective successors and assigns;
provided that no party may assign its respective rights or delegate its
respective obligations under this Agreement without the express prior written
consent of the other party hereto.

                  5.5. No Third Party Beneficiaries. Except as provided in
Article IV, there are no third party beneficiaries of this Agreement and the
provisions of this Agreement are solely for the benefit of the parties and are
not intended to confer upon any Person except the parties any rights or remedies
hereunder.

                  5.6. Notices. Any and all notices or other communications
permitted or required to be delivered or given under this Agreement shall be in
writing and signed by the party giving such notice or other communication and
shall be sent by telecopy or similar means of simultaneous transmission and
receipt or shall be delivered personally, or sent by registered or certified
mail, postage prepaid and addressed as follows:

         If to IGI, to:             Instinet Group Incorporated
                                    3 Times Square
                                    New York, NY 10036
                                    Attn: Paul Merolla, Esq.
                                    Fax: (646) 233-9017

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         If to IGLLC, to:           Instinet Group, LLC
                                    c/o Instinet Group Incorporated
                                    3 Times Square
                                    New York, NY 10036
                                    Attn: Paul Merolla, Esq.
                                    Fax: (646) 233-9017

In the case of personal delivery, the date of personal delivery or, in the case
of telecopy or similar means of simultaneous transmission and receipt, the date
of transmission or, in the case of mailing, the date of receipt, as the case may
be, shall be the date of the delivery or giving of such notice. Any party may,
by notice to the other party, change the address to which such notices are to be
given.

                  5.7. Severability. If any provision of this Agreement or the
application thereof to any Person or circumstance is determined by a court of
competent jurisdiction to be invalid, void or unenforceable, the remaining
provisions hereof, or the application of such provision to Persons or
circumstances or in jurisdictions other than those as to which it has been held
invalid or unenforceable, shall remain in full force and effect and shall in no
way be affected, impaired or invalidated thereby, so long as the economic or
legal substance of the transactions contemplated hereby is not affected in any
manner adverse to any party. Upon such determination, the parties shall
negotiate in good faith in an effort to agree upon such a suitable and equitable
provision to effect the original intent of the parties.

                  5.8. Waivers of Default. Waiver by any party of any default by
the other party of any provision of this Agreement shall not be deemed a waiver
by the waiving party of any subsequent or other default, nor shall it prejudice
the rights of the other party.

                  5.9. Amendments. No provisions of this Agreement shall be
deemed waived, amended, supplemented or modified by any party, unless such
waiver, amendment, supplement or modification is in writing and signed by the
authorized representative of the party against whom it is sought to enforce such
waiver, amendment, supplement or modification.

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                  IN WITNESS WHEREOF, the parties have caused this Agreement to
be executed by their duly authorized representatives.

                                      INSTINET GROUP INCORPORATED

                                      By: /s/ John Fay
                                          --------------------------------------
                                          Name: John Fay
                                          Title: Chief Financial Officer

                                      INSTINET GROUP, LLC

                                      By: /s/ Alex Goor
                                          --------------------------------------
                                          Name: Alex Goor
                                          Title: Executive Vice President

            [Signature Page to Contribution and Assumption Agreement]

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                                   SCHEDULE 1

SCHEDULE 1(a)(vi)  FIXED ASSETS FROM IGI TO IGLLC

SCHEDULE 1(b)-OTHER ASSETS TRANSFERRED FROM IGI TO IGLLC

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                                   SCHEDULE 2

Employees transferred from IGI to IGLLC

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