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                                                                   Exhibit 10.30



            Amendment No. 1, dated as of October 1, 2001 (this "Amendment"), to
the Interest Purchase Agreement (the "Purchase Agreement"), dated as of July 23,
2001, among Instinet Group Incorporated, a Delaware corporation ("Buyer"), and
Overunder, LLC, a Delaware limited liability company, David G. Jamail, an
individual residing in Austin, Texas, David R. Burch, an individual residing in
Austin, Texas, John A. McEntire IV, an individual residing in Austin, Texas,
John Bunda, an individual residing in Austin, Texas, Laura Horne, an individual
residing in Austin, Texas, Currin Van Eman, an individual residing in Austin,
Texas, any Drag-Along Partners (as defined in the Purchase Agreement)
(collectively, the "Sellers") and Shayne Young, an individual residing in
Austin, Texas ("Young"). Capitalized terms used but not otherwise defined herein
shall have the meanings ascribed to such terms in the Purchase Agreement.

                              W I T N E S S E T H:

            WHEREAS, Buyer, Sellers and Young have entered into the Purchase
Agreement; and

            WHEREAS, Buyer, Sellers and Young desire to amend the Purchase
Agreement, in accordance with Section 11.6 thereof.

            NOW THEREFORE, in consideration of the premises and the mutual
agreements and covenants hereinafter set forth, Buyer, each Seller and Young
agree as follows:

            1) Amendment to Section 1.1. Section 1.1 of the Purchase Agreement
      is hereby amended as follows:

            (a)   The following definitions shall be added to Section 1.1:

            "Aggregate General Indemnity Cash" means $21,521,383.62 in cash or
      immediately available funds.

            "Aggregate General Indemnity Shares" means the aggregate number of
      shares of Instinet Common Stock equal to the quotient of $38,478,625.75
      divided by the Instinet Share Price determined as of the Closing Date.

            "Aggregate Grigsby Cash" means $9,618,949.99 in cash or immediately
      available funds.

            "Aggregate Grigsby Shares" means an aggregate number of shares of
      Instinet Common Stock equal to the quotient of $381,035.89 divided by the
      Instinet Share Price determined as of the Closing Date.

            "Aggregate Stock Consideration" means an aggregate number of shares
      of Instinet Common Stock equal to the quotient of $49,999,996.92 divided
      by the Instinet Share Price determined as of the Closing Date.

            "Austin-Las Cimas Lease" shall have the meaning specified in Section
      5.14.



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<PAGE>
            "Contingency Deposit Amount" means the Contingency Escrow Amount
      less the McEntire Contingency Escrow Share.

            "Contingent Tax Liabilities" means the two potential tax liabilities
      of the ProTrader Group previously identified by the Class A Unit Holders
      and Buyer.

            "EIN" means, with respect to Persons listed on Schedule 8.1, the
      last 4 digits of such Person's social security number, or, such other code
      as ProTrader LP uses to identify such Person.

            "Grigsby Deposit Amount" means the Grigsby Escrow Amount less the
      McEntire Grigsby Escrow Share.

            "Grigsby Escrow Amount" means the Aggregate Grigsby Cash plus the
      Aggregate Grigsby Shares.

            "Houston Deposit Amount" means the Houston Interests Escrow Amount
      less the McEntire Houston Escrow Share.

            "Indemnity Deposit Amount" means (i) an amount of cash or
      immediately available funds equal to the Aggregate General Indemnity Cash
      less the McEntire General Indemnity Cash and (ii) the Aggregate General
      Indemnity Shares less the McEntire General Indemnity Shares.

            "Initial Purchase Price" shall have the meaning specified in Section
      2.2.

            "Lease Claims" shall have the meaning specified in Section 5.14.

            "Lease Claims Amount" means $700,000 in cash or immediately
      available funds.

            "Los Angeles Lease" shall have the meaning specified in Section
      5.14.

            "Management Appreciation Program" means the program for making
      incentive payments to certain members of management of the ProTrader
      Group.

            "Management Appreciation Program Amount" means an amount in cash or
      immediately available funds equal to $628,000, which is the aggregate
      amount to be paid pursuant to the Management Appreciation Program.

            "McEntire Advance" shall have the meaning specified in Section
      2.3(c).

            "McEntire Cash Consideration" means $7,338,460.00.

            "McEntire Class A Units" means the 670.930 Class A Units owned by
      McEntire as of the Closing Date.



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<PAGE>
            "McEntire Contingency Escrow Share" means an amount in cash or
      immediately available funds equal to the product of $4,500,000.01
      multiplied by McEntire's Pro-Rata Portion.

            "McEntire Escrow Claim Amount" shall have the meaning specified in
      Section 2.4(f).

            "McEntire General Indemnity Cash" means an amount in cash equal to
      the product of the Aggregate General Indemnity Cash multiplied by
      McEntire's Pro-Rata Portion.

            "McEntire General Indemnity Shares" means the number of shares of
      Instinet Common Stock equal to the product of the Aggregate General
      Indemnity Shares multiplied by McEntire's Pro-Rata Portion.

            "McEntire Grigsby Cash" means an amount in cash equal to the product
      of the Aggregate Grigsby Cash multiplied by McEntire's Pro-Rata Portion.

            "McEntire Grigsby Shares" means the number of shares of Instinet
      Common Stock equal to the product of the Aggregate Grigsby Shares
      multiplied by McEntire's Pro-Rata Portion.

            "McEntire Houston Escrow Share" means the number of shares of
      Instinet Common Stock equal to the product of the Houston Interests Escrow
      Amount multiplied by McEntire's Pro-Rata Portion.

            "McEntire Indemnity Escrow Share" means McEntire's Pro-Rata Portion
      of the Indemnity Escrow Amount, consisting of (i) the McEntire General
      Indemnity Cash and the (ii) the McEntire General Indemnity Shares.

            "McEntire Purchase Price" has the meaning set forth in Section 2A.2
      of this Agreement.

            "McEntire Grigsby Escrow Share" means McEntire's Pro-Rata Portion of
      the Grigsby Escrow Amount, consisting of (i) the McEntire Grigsby Cash and
      (ii) the McEntire Grigsby Shares.

            "McEntire Stock Consideration" means an aggregate number of shares
      of Instinet Common Stock equal to $3,863,131.00 divided by the Instinet
      Share Price determined as of the Closing Date.

            "Proprietary Trading Parties" shall have the meaning specified in
      Section 5.14.

            "Pro-Rata Portion" means, with respect to any Seller's or Young's
      participation in an escrow account established pursuant to Section 2.4,
      such Person's respective percent participation in such Escrow Account as
      reflected on Schedule 2.2 and, with respect to any Seller or Young for
      other purposes, such Person's respective percent contribution.



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<PAGE>
            "San Diego Lease" shall have the meaning specified in Section 5.14.

            "Second Closing" and "Second Closing Date" have the meanings set
      forth in Article IIA of this Agreement.

            "Section 8.1(b) Payments" shall have the meaning specified in
      Section 8.1(b).

            "Sellers' Reimbursement Account" means a bank account established
      for the benefit of Sellers and Young.

            "Tax Contingency Escrow Amount" means $1,100,000 in cash or
      immediately available funds.

            "Trader Appreciation Program" means the program for making incentive
      payments to customers of ProTrader LP or certain of its Affiliates.

            "Trader Appreciation Program Amount" means the amount in cash or
      immediately available funds equal to $ 2,957,529, which is the aggregate
      amount to be paid pursuant to the Trader Appreciation Program.

            "Transfer Agreement" shall have the meaning specified in Section
      5.14.

            "Transferred Leases" shall have the meaning specified in Section
      5.14.

            "Waiver" shall have the meaning specified in Section 8.1(a).

            (b)   The definitions of the following terms set forth in the
Agreement shall be deleted in their entirety, and the following shall be
substituted in lieu thereof:

            "Cash Consideration" means an amount in cash or immediately
      available funds equal to $100,000,000 less the Redemption Obligation
      Amount.

            "Contingency Escrow Amount" means $4,500,000.01 in cash or
      immediately available funds.

            "Execution Escrow Amount" means $15,000,000 in cash or immediately
      available funds.

            "Houston Interests Escrow Amount" means (a) an aggregate number of
      shares of Instinet Common Stock equal to the quotient of $9,999,984.07
      divided by the Instinet Share Price determined as of the Closing Date and
      (b) an amount in cash equal to $55.80.

            "Indemnity Escrow Amount" means Aggregate General Indemnity Cash
      plus the Aggregate General Indemnity Shares.

            "Instinet Common Stock" means the common stock, $0.01 par value, of
      Buyer.



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<PAGE>
            "Redemption Obligation Amount" means $6,949,645, which is the
      maximum amount payable to Grigsby as of the date hereof in respect of the
      Redemption Obligation.

            "Sellers' Expenses" means all fees and expenses payable to Bear,
      Stearns & Co. Inc. in connection with the transactions contemplated by
      this Agreement, the UAR payments and other fees and expenses (including
      legal and accounting) associated with the transaction, in each case in the
      amounts set forth in Schedule A.

            (c)   The definitions of "Purchase Price" and "Sellers' Section 8.1
Payments" set forth in the Agreement shall be deleted in their entirety.

            2) Amendment to Article II. Article II of the Purchase Agreement is
      hereby deleted and amended to read in its entirety as follows:



                                   ARTICLE II

                                  FIRST CLOSING

      On October 1, 2001 (or such other day as the Parties may agree), the
closing of the transactions provided for in this Agreement other than the
transactions contemplated in Article IIA (the "Closing") shall be held (but only
if all of the conditions set forth in Article VI (other than those conditions
that are specified as applying only to the Second Closing) shall have been
satisfied or waived prior to the Closing) at the offices of Instinet Group
Incorporated, 3 Times Square, New York, NY 10036 (such date, the "Closing
Date"). Each of the Parties hereby agrees that the following actions shall occur
and be effective at and as of the Closing.

      2.1   Acquisition and Transfer of certain ProTrader LP Units and the
ProTrader LLC Interests. In reliance upon the representations, warranties,
covenants and agreements contained herein and upon the terms and subject to the
conditions set forth in Article VI hereof, at the Closing:

            (A)   Burch, Jamail and Overunder shall sell, assign, transfer,
convey and deliver to Buyer, and Buyer shall purchase, acquire and accept from
Burch, Jamail and Overunder, in each case free and clear of all Liens (other
than Liens created by the terms of the ProTrader LP Partnership Agreement or the
ProTrader LLC Limited Liability Company Agreement, as applicable, which, with
respect to any holders (other than Buyer) of Units or ProTrader LLC Membership
Interests as of or prior to Closing, shall be extinguished or irrevocably waived
upon the Closing) (i) all of the Class A Units (other than the McEntire Class A
Units) and (ii) one hundred percent (100%) of the ProTrader LLC Membership
Interests (other than the ProTrader LLC Membership Interests owned by McEntire
as of the Closing);

            (B)   the Class B Unit Holders shall sell, assign, transfer, convey
and deliver to Buyer, and Buyer shall purchase, acquire and accept from such
Class B Unit Holders, free and clear of all Liens (other than Liens created by
the terms of the ProTrader LP Partnership Agreement or the ProTrader LLC Limited
Liability Company Agreement, as applicable, which,


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with respect to any holders (other than Buyer) of Units or ProTrader LLC
Membership Interests as of or prior to Closing, shall be extinguished or
irrevocably waived upon the Closing) all of the Class B Units; and

            (C)   the Class C Units Holders shall sell, assign, transfer, convey
and deliver to Buyer, and Buyer shall purchase, acquire and accept from the
Class C Unit Holders, free and clear of all Liens (other than Liens created by
the terms of the ProTrader LP Partnership Agreement or the ProTrader LLC Limited
Liability Company Agreement, as applicable, which, with respect to any holders
(other than Buyer) of Units or ProTrader LLC Membership Interests as of or prior
to Closing, shall be extinguished or irrevocably waived upon the Closing), all
of the Class C Units.

      2.2   Initial Purchase Price. The aggregate consideration (the "Initial
Purchase Price") for the Class A Units (other than the McEntire Class A Units),
the Class B Units (if any), the Class C Units and the ProTrader LLC Membership
Interests owned by the Sellers (other than McEntire) shall be (i) the Cash
Consideration less the McEntire Cash Consideration and (ii) the Aggregate Stock
Consideration less the McEntire Stock Consideration.

      2.3   Payment Priority.

      (a)   At, or where indicated below promptly after, the Closing, the
Initial Purchase Price shall be paid in the following manner: (i) Buyer shall
deliver the Indemnity Deposit Amount to the Escrow Agent pursuant to the terms
of the Escrow Agreement in accordance with Section 2.4(a), (ii) unless the
purchase of the Houston Interests is consummated at or prior to Closing, Buyer
shall deliver the Houston Deposit Amount to the Escrow Agent pursuant to the
terms of the Escrow Agreement in accordance with Section 2.4(b), (iii) Buyer
shall deliver the Contingency Deposit Amount to the Escrow Agent pursuant to the
terms of the Escrow Agreement in accordance with Section 2.4(c), (iv) Buyer
shall deliver the Execution Escrow Amount pursuant to the terms of the Escrow
Agreement in accordance with Section 2.4(d), (v) Buyer shall deliver the Grigsby
Escrow Amount to the Escrow Agent pursuant to the terms of the Escrow Agreement
in accordance with Section 2.4(e), (vi) Buyer shall pay, at or promptly after
the Closing, to the Persons specified on Schedule A on behalf of ProTrader LP
out of the Cash Consideration an amount equal to the aggregate Sellers' Expenses
less an amount equal to the product of (x) the aggregate Sellers' Expenses
multiplied by (y) 8.75377%, (vii) Buyer shall, as promptly as practical after
the Closing, pay on behalf of ProTrader LP out of the Cash Consideration an
amount equal to (x) a portion of the Section 8.1(b) Payments equal to $1,370,652
plus $ 2,262,861 (which equals the aggregate amounts indicated in the column
"Vested Obligation" on Schedule 8.1 with respect to the holders of vested
Options) to the Persons whose EINs are set forth on Schedule 8.1 plus the Trader
Appreciation Program Amount to the Persons to whom such amounts are to be paid
plus the Management Appreciation Program Amount to the Persons to whom such
amounts are to be paid less (y) an amount equal to the sum of the amounts listed
above in Section 2.3(a)(vii)(x) multiplied by 8.75377% and (viii) Buyer shall
deposit out of the Cash Consideration an amount equal to $3,727,838.00 in cash
or immediately available funds into the Sellers' Reimbursement Account, in
accordance with the wire transfer instructions previously provided to Buyer. The
Trader Appreciation Program Amount shall be paid to such Persons, in such
amounts, and subject to such terms and conditions as set by McEntire in his
reasonable discretion. Buyer shall endeavor in good faith to obtain


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releases, in a form reasonably satisfactory to the Seller's Representative, from
the recipients of such payments prior to making such payments. To the extent
that the actual aggregate dollar amount of the invoices delivered in connection
with the expenses itemized on Schedule A is less than the aggregate amounts
reflected on Schedule A, Buyer shall cause the difference to be deposited in the
Seller's Reimbursement Account, as promptly as practicable after the payment in
full of such invoices. Buyer shall pay the remaining Initial Purchase Price to
the Persons as specified in Section 2.3(b). The Parties acknowledge that the
amounts paid pursuant to Section 2.3(a)(vii) (other than the amount related to
the Trader Appreciation Program) are obligations of ProTrader LP that accrued
immediately prior to, and as a result of, the Closing and shall be paid by, or
on behalf of, ProTrader LP promptly after the Closing and that any tax deduction
related to such amounts (other than the amount related to the Trader
Appreciation Program) shall be taken into account on a tax return for ProTrader
LP for the period ending on the Closing Date.

      (b)   Buyer shall wire transfer the remainder of the Cash Consideration
(other than (i) the McEntire Cash Consideration or (ii) any portion of the Cash
Consideration to be paid to the Houston Trader Group at the Closing) to the
Sellers (other than McEntire) and Young in the amounts specified on Schedule 2.2
as cash proceeds at close in immediately available funds to a bank account or
bank accounts designated by Sellers no later than five (5) Business Days prior
to the Closing and shall deliver to Sellers (other than McEntire) and Young the
portion of the Stock Consideration specified as stock proceeds at close on
Schedule 2.2.

      (c)   In addition to the amounts to be paid in accordance with Sections
2.3(a) and 2.3(b), the following amounts shall be paid at, or where indicated
below promptly after, the Closing in the following manner: (i) Buyer shall pay
to the Persons specified on Schedule A on behalf of ProTrader LP an amount equal
to the aggregate Sellers' Expenses multiplied by 8.75377%, (ii) Buyer shall
promptly after the Closing pay in accordance with Section 2.3(a) on behalf of
ProTrader LP an amount equal to the product of (A) the sum of the amounts listed
in Section 2.3(a)(vii)(x) multiplied by (B) 8.75377% and (iii) Buyer shall
deposit an amount equal to $357,633.00 in cash or immediately available funds
into the Sellers' Reimbursement Account, in accordance with the wire transfer
instructions previously provided to Buyer. The amounts paid at Closing by Buyer
pursuant to this Section 2.3(c) shall bear interest at a rate of 5% per annum
and shall be considered an advance (such amounts, including accrued interest,
the "McEntire Advance") of (x) a portion of the McEntire Cash Consideration to
be paid by Buyer at the Second Closing and (y) any other amounts to be paid by
Buyer or any of its Affiliates to McEntire under any agreement between Buyer, or
any of its Affiliates, and McEntire. The McEntire Advance may be deducted by
Buyer from the McEntire Purchase Price in accordance with Section 2A.2 or, if
the Second Closing does not occur prior to January 2, 2002, from any other
amounts to be paid by Buyer or any of its Affiliates to McEntire under any
agreement between Buyer, or any of its Affiliates, and McEntire. The Parties
acknowledge that the amounts paid by Buyer pursuant to Section 2.3(c)(ii) (other
than the amount related to the Trader Appreciation Program) are obligations of
ProTrader LP that accrued immediately prior to, and as a result of, the Closing
and shall be paid by or on behalf of ProTrader LP promptly after the Closing and
that any tax deduction related to such amounts shall be taken into account on a
tax return for ProTrader LP for the period ending on the Closing Date.



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<PAGE>
      2.4   Escrow Accounts.

      (a)   Buyer shall place the Indemnity Deposit Amount into an escrow
account (or separate escrow accounts) (the "Indemnification Escrow Account")
pursuant to the Escrow Agreement (as defined below). Subject to the other
provisions of this Section 2.4, the Indemnity Deposit Amount shall be maintained
to provide Buyer with payment of indemnification claims that may become owing by
the Class A Unit Holders under the provisions of this Agreement. Such escrow
will be established pursuant to an escrow agreement, dated the date hereof (the
"Escrow Agreement") among Buyer, Sellers, Young and Comerica Securities, Inc.
(the "Escrow Agent") in a form agreed to by Buyer, Sellers, Young and the Escrow
Agent. The Indemnity Deposit Amount, together with the McEntire Indemnity Escrow
Share to be delivered to the Escrow Agent pursuant to Section 2A.4, constitute
the Indemnification Escrow Amount. On the first anniversary of the Closing and
subject to the last sentence of this Section 2.4(a), any portion of the
Indemnification Escrow Amount that has not been released to Buyer for the
payment of such amounts as may be due under Section 9.2 and are not subject to
pending indemnification claims shall be released to the Class A Unit Holders in
their respective percent participation in the Indemnification Escrow Account and
in accordance with the terms of the Escrow Agreement. Any portion of the
Indemnification Escrow Amount that is not so released pending an indemnification
claim shall be released when the claim is resolved. Anything in this Section
2.4(a) to the contrary notwithstanding, (i) the Tax Contingency Escrow Amount
shall remain in the Indemnification Escrow Account until the later to occur of
(x) the lapse of all applicable statutes of limitations for any claims relating
to the Contingent Tax Liabilities or (y) the final termination of any audit
relating to the Contingent Tax Liabilities if such audit shall have commenced
prior to the occurrence of (x); provided that, after the first anniversary of
the Closing, the Class A Unit Holders may substitute for the Tax Contingency
Amount in escrow an irrevocable letter of credit for the benefit of Buyer in a
form reasonably satisfactory to Buyer, for a term no shorter than the term that
would have applied to the escrow of such Tax Contingency Amount in the absence
of such substitution and in an amount equal to the Tax Contingency Escrow Amount
and (ii) the Lease Claims Amount shall remain in the Indemnification Escrow
Account until the earlier to occur of (x) the receipt by Buyer of releases duly
executed by the lessors under the Transferred Leases, releasing each member of
the ProTrader Group, which is the lessee or is otherwise liable under the
applicable Transferred Lease from the Lease Claims, (y) the lapse of all
applicable statutes of limitations for any claims relating to the Lease Claims
or (z) the termination of all Transferred Leases and the receipt by Buyer of
evidence (in a form reasonably satisfactory to Buyer) that all rent owed and
other amounts due under the Transferred Leases have been paid in full.

      (b)   Unless the purchase of the Houston Interests is consummated at or
prior to the Closing, Buyer also shall place the Houston Deposit Amount in
separate subaccounts of the Indemnification Escrow Account (or in separate
escrow accounts) pursuant to the Escrow Agreement. The Houston Deposit Amount,
together with the McEntire Houston Escrow Share to be delivered to the Escrow
Agent pursuant to Section 2A.4, constitute the Houston Interests Escrow Amount.
The Houston Interests Escrow Amount shall be used to compensate Buyer for, or to
allow Buyer to pay on behalf of itself or the ProTrader Group, any liability
relating to the subject matter of Section 5.7 and shall be maintained until the
closing of the purchase of Houston Interests pursuant to Section 5.7. Buyer,
Sellers and Young agree that the Houston Interests


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Escrow Amount (i) does not represent an acknowledgement on the part of any Party
on the amount of any potential liability to the Trader Group and (ii) is
substantially in excess of any such potential liability. Notwithstanding the
preceding sentence, Buyer, Sellers and Young agree that Buyer shall be entitled
to obtain up to the full amount of the Houston Interests Escrow Amount in order
to compensate Buyer for, or to allow Buyer to pay on behalf of itself or the
ProTrader Group, any liability relating to the subject matter of Section 5.7.
Any portion of the Houston Interests Escrow Amount that has not been released to
Buyer and is not subject to a pending claim shall be released to Sellers and
Young based on their respective Pro-Rata Portion of such Escrow Amount upon the
earlier to occur of (i) the consummation of the acquisition of the Houston
Interests pursuant to the Tag-Along Agreement or (ii) the lapse of all
applicable statutes of limitations for any claim or potential claim under
Section 5.7.

      (c)   Buyer also shall place the Contingency Deposit Amount in separate
subaccounts of the Indemnification Escrow Account (or in separate escrow
accounts) pursuant to the Escrow Agreement. The Contingency Deposit Amount,
together with the McEntire Contingency Escrow Share to be delivered to the
Escrow Agent pursuant to Section 2A.4, constitute the Contingency Escrow Amount.
The Contingency Escrow Amount shall be used to compensate Buyer for, or to allow
Buyer to pay on behalf of itself or the ProTrader Group, any liability relating
to the subject matter of Section 5.10. Buyer, Sellers and Young hereby agree and
acknowledge that nothing in this Section 2.4(c) is or shall be deemed an
admission or recognition by any Party of liability with respect to any claim or
potential claim that may be brought against such Party with respect to the
subject matter hereof. In addition, Buyer, Sellers and Young agree that the
Contingency Escrow Amount represents a substantial over-collateralization for
any foreseeable liability arising out of the subject matter hereof.
Notwithstanding the preceding sentence, Buyer, Sellers and Young agree that
Buyer shall be entitled to obtain up to the full amount of the Contingency
Escrow Amount in order to compensate Buyer for, or to allow Buyer to pay on
behalf of itself or the ProTrader Group, any liability relating to the subject
matter of Section 5.10. Any portion of the Contingency Escrow Amount not
released to Buyer or subject to a pending claim shall be released to Sellers and
Young based on their respective Pro-Rata Portion of such Escrow Amount upon the
earliest to occur of (i) settlement of all claims arising pursuant to Section
5.10 or (ii) the lapse of all applicable statutes of limitations for any claim
or potential claim under Section 5.10.

      (d)   Buyer also shall place the Execution Escrow Amount in escrow, such
escrow to be maintained until sixty (60) days after the third anniversary of the
Closing Date to provide for the payment of certain minimum commission amounts
that will be owed under the Execution Agreement. Such escrow will be established
pursuant to the Escrow Agreement. On a monthly basis (and for each month, in no
event later than the 15th calendar day of the succeeding month), for every $1
million of Fees (as defined in the Execution Agreement) accrued under the
Execution Agreement, an aggregate of $500,000 from the Execution Escrow Amount
shall be released to Burch, Jamail and Overunder, to be divided among them
according to their respective Pro-Rata Shares (as defined in the Execution
Agreement). If Buyer or any of its Affiliates have not received the minimum
commission payments due under the Execution Agreement within 3 days of such
amounts being due, Buyer shall be entitled to obtain payment of all or a portion
of such minimum commission payment due from the Execution Escrow Amount.



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<PAGE>
      (e)   Buyer also shall place the Grigsby Deposit Amount in separate
subaccounts of the Indemnification Escrow Account (or in separate escrow
accounts) pursuant to the Escrow Agreement. The Grigsby Deposit Amount, together
with the McEntire Grigsby Escrow Share to be delivered to the Escrow Agent
pursuant to Section 2A.4 constitutes the Grigsby Escrow Amount. The Grigsby
Escrow Amount shall be used to compensate Buyer for, or to allow Buyer to pay on
behalf of itself or the ProTrader Group, any amounts owed to Grigsby (whether
under the Redemption Agreement or otherwise) in excess of the Redemption
Obligation Amount (x) by any member of the ProTrader Group or (y) by Buyer as
the result of the transactions contemplated by this Agreement. Buyer, Sellers
and Young hereby agree and acknowledge that nothing in this Section 2.4(e) is or
shall be deemed an admission or recognition by any Party of liability with
respect to any claim or potential claim that may be brought against such Party
with respect to the subject matter hereof. Notwithstanding the preceding
sentence, Buyer, Sellers and Young agree that Buyer shall be entitled to obtain
up to the full amount of the Grigsby Escrow Amount in order to compensate Buyer
for, or to allow Buyer to pay on behalf of itself or the ProTrader Group, any
liability relating to the subject matter hereof. Any portion of the Grigsby
Escrow Amount not released to Buyer or subject to a pending claim shall be
released to Sellers and Young based on their respective Pro-Rata Portion of such
Escrow Amount upon the earliest to occur of (i) the settlement of all claims by
Grigsby against Buyer or any member of the ProTrader Group or (ii) the lapse of
all applicable statutes of limitations for any claim or potential claim that
could by brought by Grigsby (x) against any member of the ProTrader Group or (y)
against Buyer as the result of the transactions contemplated by this Agreement.
Notwithstanding any other provision herein to the contrary, the Parties agree
that any amounts owed to Buyer pursuant to this Section 2.4(e) shall be offset
to the extent of any amounts paid by Grigsby to ProTrader LP or any of its
Affiliates pursuant to the indemnification provisions of the Grigsby Redemption
Agreement.

      (f)   Anything in this Agreement to the contrary notwithstanding, the
McEntire Indemnity Escrow Share, the McEntire Houston Escrow Share, the McEntire
Contingency Escrow Share and the McEntire Grigsby Escrow Share shall be deemed
to have been deposited into escrow as of the Closing to cover McEntire's share
of the escrow obligations under this Section 2.4 and the Escrow Agreement.
McEntire hereby agrees to be responsible for, and to pay, his Pro-Rata Portion
of any payments to be made pursuant to the applicable terms of this Agreement
and the Escrow Agreement. In the event Buyer makes a valid claim payable under
the Escrow Agreement prior to the actual deposit in escrow of the McEntire
Indemnity Escrow Share, the McEntire Houston Escrow Share, the McEntire
Contingency Escrow Share and the McEntire Grigsby Escrow Share, McEntire's
Pro-Rata Portion of all such claims (the "McEntire Escrow Claim Amount") will be
deemed to be deducted from the applicable subaccount for the purposes of
determining the other Sellers' respective Pro-Rata Portions and the McEntire
Purchase Price shall be reduced by the McEntire Escrow Claim Amount or, if the
Second Closing has not occurred on or before January 2, 2002 (or such later date
as mutually agreed by Buyer and McEntire), McEntire shall promptly pay the
McEntire Escrow Claim Amount to Buyer.



                                       10
<PAGE>
      (g)   On or after the Closing Date upon three Business Days' notice to
Buyer:

                  (i)   any Class A Unit Holder may substitute an amount in cash
      for such Class A Unit Holder's Pro-Rata Portion of the shares of Instinet
      Common Stock then held in escrow pursuant to Section 2.4(a) (or any
      portion thereof) equal to such Seller's Pro-Rata Portion of $38,478,625.75
      less amounts previously paid out pursuant to the indemnification
      provisions of this Agreement and the Escrow Agreement;

                  (ii)  any Seller or Young may substitute an amount in cash for
      such Person's Pro-Rata Portion of the shares of Instinet Common Stock then
      held in escrow pursuant to Section 2.4(b) (or any portion thereof) equal
      to such Person's Pro-Rata Portion of $9,999,984.07 less amounts previously
      paid out pursuant to the indemnification provisions of this Agreement and
      the Escrow Agreement; and

                  (iii) any Seller or Young may substitute an amount in cash for
      such Person's Pro-Rata Portion of the shares of Instinet Common Stock then
      held in escrow pursuant to Section 2.4(e) (or any portion thereof) equal
      to such Person's Pro-Rata Portion of $381,035.89 less amounts previously
      paid out pursuant to the indemnification provisions of this Agreement and
      the Escrow Agreement;

                  (iv)  in the event that all of the Instinet Common Stock held
      in escrow pursuant to Sections 2.4(a), 2.4(b) or 2.4(e) has been
      substituted with cash pursuant to this Section 2.4(g), any Class A Unit
      Holder, with respect to Section 2.4(a), or any Seller or Young, with
      respect to Sections 2.4(b) or 2.4(e), may withdraw such Person's Pro-Rata
      Portion of any amount then held in such escrow in excess of $50,000,000,
      with respect to Section 2.4(a), $10,000,000, with respect to Sections
      2.4(b) and $381,035.89, with respect to Section 2.4(e).

      2.5   Closing and Pre-Closing Deliveries.

      (a)   Sellers shall deliver to Buyer, no later than five (5) Business Days
prior to the Closing Date, (i) Schedule 2.2 setting forth (A) for each Seller,
the number of Class A Units, Class B Units, Class C Units and Class D Units and
percentage of ProTrader LLC Membership Interests, as applicable, that such
Sellers shall convey to Buyer at the Closing pursuant to Section 2.1 (or, in the
case of McEntire, that will be conveyed at the Second Closing) and (B) each of
the Sellers' and Young's Pro-Rata Portion, (ii) a certificate duly executed by
the Class A Unit Holders certifying the Redemption Obligation Amount as of the
Closing Date and detailing any amounts paid to Grigsby in connection with the
Redemption Obligation since May 31, 2001, (iii) Schedule A setting forth the
Sellers' Expenses and (iv) an updated Schedule 8.1.

      (b)   No later than five (5) Business Days prior to the Closing Date,
Sellers shall deliver to Buyer a completed consolidated statement of income of
ProTrader LP from May 31, 2001 until the date of delivery, duly executed by the
Class A Unit Holders, setting forth the Class A Unit Holders' good faith
estimate of the consolidated net income of ProTrader LP (the "Interim Net Income
Statement").




                                       11
<PAGE>
      (c)   At the Closing, the Parties shall exchange the documents referred to
in Article VI, Burch, Jamail and Overunder shall deliver to Buyer assignments
and other instruments in form and substance reasonably acceptable to Buyer
evidencing the sale, assignment, transfer and conveyance (including the waiver
of any preemptive rights, rights of first refusal, tag-along rights or other
similar rights pursuant to any ProTrader Constituent Document) to Buyer of the
Class A Units (other than the McEntire Class A Units) and the ProTrader LLC
Membership Interests (other than the Membership Interests owned by McEntire),
the Class B Unit Holders, if any, shall deliver to Buyer assignments and other
instruments in form and substance reasonably acceptable to Buyer evidencing the
sale, assignment, transfer and conveyance (including the waiver of any
preemptive rights, rights of first refusal, tag-along rights or other similar
rights pursuant to any ProTrader Constituent Document) to Buyer of the Class B
Units, and the Class C Unit Holders shall deliver to Buyer assignments and other
instruments in form and substance reasonably acceptable to Buyer evidencing the
sale, assignment, transfer and conveyance (including the waiver of any
preemptive rights, rights of first refusal, tag-along rights or other similar
rights pursuant to any ProTrader Constituent Document) to Buyer of the Class C
Units. In addition, at the Closing each of Burch, Jamail, Kershner and McEntire
shall deliver to Buyer his resignation from the Management Committee of the
general partner of ProTrader LP.

      (d)   In the event that Buyer disputes the Interim Net Income Statement,
Buyer shall, no later than 30 days after the Closing Date, describe to Sellers
in reasonable written detail the basis for such dispute, and Buyer and Sellers
shall promptly negotiate in good faith to resolve such dispute. If Buyer fails
to deliver such a notice of dispute within such 30-day period, Buyer shall be
deemed to have accepted as final such Interim Net Income Statement. If Buyer
delivers to Seller a notice of dispute and if such dispute is not resolved
within 30 days after Buyer shall have notified Sellers of its basis for such
dispute, then the specific matters in dispute shall be submitted to a nationally
recognized independent accounting firm (other than PricewaterhouseCoopers LLP or
Ernst and Young) reasonably acceptable to Buyer and Sellers. Buyer shall have
the right to examine and make copies of any work papers, including the work
papers of Ernst & Young, used in connection with the preparation of the Interim
Net Income Statement.

            Such accounting firm shall be requested to provide its resolution of
the matters in dispute within 30 days of submission thereof to such firm, and
the determination of such accounting firm in respect of each of the matters in
dispute shall be conclusive and binding on Buyer and Sellers save for manifest
error. The determination of such firm shall be final and determinative. Payment
of the amount of any adjustment shall be made by wire transfer of immediately
available funds to the prevailing Party within two Business Days of the final
determination thereof.

      The fees and expenses of such accounting firm shall be (i) paid by
Sellers, if the excess (the "Interim Net Income Differential") of the
consolidated net income of ProTrader as set forth on the Interim Net Income
Statement over the consolidated net income of ProTrader as determined by such
accounting firm is greater than 5%, (ii) shared equally by Sellers (in the
aggregate) and Buyer if the Interim Net Income Differential is equal to or less
than 5% and equal to or greater than 1%, and (iii) paid by Buyer if the Interim
Net Income Differential is less than 1%.



                                       12
<PAGE>
            3) New Article IIA. The Purchase Agreement is amended by adding the
following new Article IIA immediately following Article II thereof:



                                   ARTICLE IIA

                                 SECOND CLOSING

      On January 2, 2002 (or such other day as Buyer and McEntire may agree),
the closing of the transactions provided for in this Article IIA (the "Second
Closing") shall be held (but only if all the conditions set forth in Section 6.3
shall have been satisfied or waived prior to the Second Closing) at the offices
of Instinet Group Incorporated, 3 Times Square, New York, NY 10036 (such date,
the "Second Closing Date").

      2A.1  Acquisition and Transfer of Class D Units, McEntire Class A Units
and ProTrader LLC Interest. In reliance upon the representations, warranties,
covenants and agreements contained herein and subject to the conditions set
forth in Section 6.3, at the Second Closing McEntire shall sell, assign,
transfer, convey and deliver to Buyer, and Buyer shall purchase, acquire, and
accept from McEntire, free and clear of all Liens, all of the Class D Units, the
McEntire Class A Units, and the ProTrader LLC Membership Interests owned by
McEntire as of the Closing, together with all property other than cash received
by McEntire as distributions on any such Units or Membership Interests between
the Closing and the Second Closing.

      2A.2  McEntire Purchase Price. The aggregate consideration for the Class D
Units, the McEntire Class A Units, the Membership Interests and any other
property sold pursuant to Section 2A.1 (the "McEntire Purchase Price") shall be
(i) the sum of (x) the McEntire Stock Consideration and (y) the McEntire Cash
Consideration less (ii) the sum of (x) any amount of the McEntire Advance still
owed by McEntire to Buyer as of Second Closing and (y) the McEntire Escrow Claim
Amount.

      2A.3  Payment Priority.

      (a)   At the Second Closing, the McEntire Purchase Price shall be paid in
the following manner: (i) Buyer shall deliver the McEntire Indemnity Escrow
Share to the Escrow Agent pursuant to the Escrow Agreement in accordance with
Section 2A.4(a), (ii) unless the purchase of the Houston Interests is
consummated at or prior to the Second Closing, Buyer shall deliver the McEntire
Houston Escrow Share to the Escrow Agent pursuant to the terms of the Escrow
Agreement in accordance with Section 2A.4(b), (iii) Buyer shall deliver the
McEntire Contingency Escrow Share to the Escrow Agent pursuant to the terms of
the Escrow Agreement in accordance with Section 2A.4(c) and (iv) Buyer shall
deliver the McEntire Grigsby Escrow Share to the Escrow Agent pursuant to the
terms of the Escrow Agreement in accordance with Section 2A.4(d). Buyer shall
pay the remaining McEntire Purchase Price to McEntire as specified in Section
2A.3(b).

      (b)   Buyer shall wire transfer the McEntire Cash Consideration (other
than any portion thereof to be paid to any other Person in accordance with
Section 2A.3(a) or to be placed into


                                       13
<PAGE>
escrow pursuant to Section 2A.4) to McEntire in immediately available funds to
the bank account previously designated by McEntire.

      2A.4  McEntire Escrow

      (a)   Buyer shall place the McEntire Indemnity Escrow Share in the
Indemnification Escrow Account.

      (b)   Unless the purchase of the Houston Interests is consummated at or
prior to the Second Closing, Buyer shall place the McEntire Houston Escrow Share
in the subaccount of the Indemnification Escrow Account (or a separate escrow
account) referenced in Section 2.4(b).

      (c)   Buyer shall place the McEntire Contingency Escrow Share in the
subaccount of the Indemnification Escrow Account (or a separate escrow account)
referenced in Section 2.4(c).

      (d)   Buyer shall place the McEntire Grigsby Escrow Share in the
subaccount of the Indemnification Escrow Account (or a separate escrow account)
referenced in Section 2.4(e).

      2A.5  Second Closing Deliveries. At the Second Closing, McEntire shall
deliver to Buyer the certificate referred to in Section 6.3 and assignments and
other instruments in form and substance reasonably acceptable to Buyer
evidencing the sale, assignment, transfer and conveyance (including the waiver
of any preemptive rights, rights of first refusal, tag-along rights or other
similar rights pursuant to any ProTrader Constituent Document) to Buyer of the
Class D Units, the McEntire Class A Units, the ProTrader LLC Membership
Interests owned by McEntire as of the Closing and any other property transferred
by McEntire in accordance with Section 2A.1.

            4) Amendment to Section 3.4(f): Section 3.4(f) of the Purchase
Agreement is hereby amended in its entirety to read as follows:

      (f)   As of the date hereof, the maximum amount payable to Grigsby in
respect of the Redemption Obligation is $6,949,645. All amounts due and payable
to Grigsby through the date hereof in accordance with the Redemption Obligation
have been paid. The aggregate amount that ProTrader Group owes to Grigsby,
whether contingent or otherwise and whether arising under the Grigsby Redemption
Agreement or otherwise, does not exceed $6,949,645.

            5) Amendment to Section 5.13: Section 5.13 of the Purchase Agreement
is hereby amended in its entirety to read as follows:

      5.13  Amendment of or Waiver Under ProTrader Constituent Documents

      (a)   Effective as of the Closing, Article 12 of the ProTrader LP
Partnership Agreement and Article 14 of the ProTrader LLC Limited Liability
Company Agreement shall terminate and have no force and effect and Sellers shall
irrevocably waive any rights to indemnification pursuant to such Articles
(except with respect to liabilities arising prior to the Closing that are duly
recorded on the Interim Financial Statements).



                                       14
<PAGE>
      (b)   Effective as of the Closing, Section 6.1 of the ProTrader LP
Partnership Agreement shall be amended to read as follows:

            6.1 Distributable Cash. Subject to Sections 3.3 and 3.5,
Distributable Cash shall be distributed to the Holders from time to time at the
sole discretion of the Management Committee of the General Partner.

      (c)   Effective as of the Closing, Section 9.7 of the ProTrader LLC
Limited Liability Company Agreement shall be amended to read as follows:

            9.7 Distributable Cash. Subject to Sections 7.3 and 7.5,
Distributable Cash of the Company shall be distributed to the Members pro rata
in accordance with their respective Membership Interests from time to time at
the sole discretion of the Management Committee.

            6) New Section 5.14. The Purchase Agreement is amended by adding the
following new Section 5.14 immediately following Section 5.13 thereof.

      5.14  Certain Transferred Leases. Pursuant to that certain Transfer
Agreement (the "Transfer Agreement"), dated as of August 31, 2001, by and among
PROTRADER TRADING LLC, PTPHC, LP, Burch, Jamail, Overunder (collectively, the
"Proprietary Trading Parties") and ProTrader LP, ProTrader LP transferred its
rights and agreed to cause its Affiliates to transfer their rights, if any,
under certain office leases (the "Austin-Las Cimas Lease, the "San Diego Lease"
and the "Los Angeles Lease" as described on Schedule 1.1 (d) to the Transfer
Agreement and collectively, the "Transferred Leases") to the Proprietary Trading
Parties. Burch, Jamail and Overunder shall use their reasonable best efforts to
obtain releases duly executed by the lessors under the Transferred Leases,
releasing each member of the ProTrader Group, which is the lessee or is
otherwise liable under the Transferred Leases from any claims (the "Lease
Claims") such lessors may have against such member or members of the ProTrader
Group (x) arising on or after August 31, 2001 with respect to the San Diego
Lease and the Los Angeles Lease and (y) arising prior to, on or after August 31,
2001 with respect to the Austin-Las Cimas Lease. Notwithstanding the foregoing
and without limiting any of the Buyer's rights under this Agreement, the Parties
acknowledge that the Lease Claims shall be considered Proprietary Trading
Business Liabilities for purposes of Section 9.2.

      5.15  Additional Agreements Related to Grigsby. (a) On a quarterly basis
beginning at the end of the fiscal quarter in which the Closing occurs, to the
extent that the aggregate amount of the payments made to Grigsby under the
Grigsby Redemption Agreement during such quarter is less than $637,500, Buyer
agrees, within 5 days of the end of the quarter, to pay such difference to the
Escrow Agent for deposit into the Grigsby Escrow Account.

      (b)   Buyer authorizes Sellers to offer to Grigsby solely in connection
with the settlement in full of all potential claims that Grigsby may have under
the Grigsby Redemption Obligation or otherwise, a payment of the Redemption
Obligation Amount on an accelerated basis, and Buyer agrees to pay such amount;
provided that, such payment is, in whole or in part, in consideration for a
general release of all claims that Grigsby may have against Buyer, ProTrader LP,
ProTrader LLC or any of their respective Subsidiaries.



                                       15
<PAGE>
            7) Amendment to Article VI: Article VI of the Purchase Agreement is
hereby amended as follows.

            (a)   Section 6.2(i) is hereby deleted and amended to read, in its
      entirety, as follows:

      (i)   Buyer shall have established an irrevocable stand-by letter of
credit from a lending institution with a rating of A-1 plus (as issued by Moodys
or Standard & Poors) in support of ProTrader LP's obligations to Grigsby under
the Grigsby Redemption Agreement, in an aggregate amount equal to $6,949,645.

            (b)   Section 6.2 (j) is hereby deleted in its entirety.

            (c)   The following new Section 6.3 is hereby added immediately
      following Section 6.2 of the Purchase Agreement.

      6.3   Conditions to Second Closing. The obligations of Buyer to consummate
the Second Closing are subject to the satisfaction at or prior to the Second
Closing of each of the conditions set forth below; provided, however, that
notwithstanding the failure of any or all of such conditions, Buyer may
nevertheless proceed with the Closing without satisfaction, in whole or in part,
of any or all of such conditions, but only if a written waiver thereof is
executed by Buyer:

      (a)   The Closing shall have occurred.

      (b)   Each of the representations and warranties of McEntire contained in
Section 3A.3 shall be true and correct in all material respects (other than such
representations and warranties that are qualified by a materiality standard,
which representations shall be true and correct in all respects) on and as of
the Second Closing Date with the same force and effect as though the same had
been made on the Second Closing Date.

      (c)   All of the covenants and agreements required by this Agreement to
have been performed and complied with by McEntire prior to or on the Second
Closing Date shall have been performed and complied with prior to the Second
Closing Date.

      (d)   No preliminary or permanent injunction or other Judgment of any
court restraining or prohibiting the consummation of the transactions
contemplated hereby shall be in effect. No Proceedings shall have been
instituted or threatened by any Person (including any Authority) seeking to
prohibit, restrict or delay, declare illegal or to enjoin or obtain Damages from
Buyer in respect of, the consummation of the transactions contemplated by
Article IIA.

      (e)   No action shall have been taken by any Authority that would
prohibit, restrict, delay, render illegal or enjoin the consummation of the
transactions contemplated by Article IIA.

      (f)   Buyer shall receive a certificate, dated as of the Second Closing
Date, from McEntire as to the satisfaction of the conditions set forth in
Section 6.3(b) and (c).



                                       16
<PAGE>
            8) Amendment to Section 8.1. Section 8.1 of the Purchase Agreement
is hereby amended in its entirety to read as follows:

            8.1   Stock Option.

            (a)   At the Closing, each Option which (i) was vested as of July
23, 2001, (ii) is outstanding as of the Closing and (iii) is held by a Person
(x) who is listed as a holder of vested Options on Schedule 8.1 and (y) who on
or prior to the Closing executes and delivers to ProTrader LP an "Options
Surrender Agreement, Release, Waiver and Acknowledgement," substantially in the
form attached as Exhibit E (the "Waiver") shall be cancelled and the holder of
such Option shall be entitled to receive from ProTrader LP the amounts indicated
in the column "Vested Obligation" opposite such holder's EIN on Schedule 8.1,
which payment shall be in full settlement and satisfaction of the rights of such
Option holder in respect of each such Option.

            (b)   At the Closing, each Option which (i) was unvested as of July
23, 2001, (ii) is outstanding as of the Closing, and (iii) is held by a Person
(x) with a positive amount indicated in the column "Total Unvested Obligation"
opposite such Person's EIN on Schedule 8.1 and (y) who on or prior to the
Closing executes and delivers to ProTrader LP a Waiver shall be cancelled and
the holder of such Option shall be entitled to receive from ProTrader LP, at the
time and subject to the conditions set forth in Schedule 8.1, the cash payments
indicated in the column "Total Unvested Obligation" opposite such holder's EIN
on Schedule 8.1 in full settlement and satisfaction of the rights of such Option
holder in respect of each such Option. Promptly following Closing, ProTrader LP
shall pay to such holders those amounts (the "Section 8.1(b) Payments")
indicated in the columns "Instinet Contribution-Payable Promptly After Closing"
and "ProTrader Contribution-Payable Promptly After Closing" opposite each such
holder's EIN on Schedule 8.1. At the time and subject to the conditions set
forth on Schedule 8.1, ProTrader LP shall pay to such holders those amounts
indicated in the column "Deferred Portion" opposite each such holder's EIN on
Schedule 8.1.

            (c)   Pursuant to the terms of the Unit Option Plan, effective as of
the Closing, each Option which was (i) unvested as of July 23, 2001, (ii)
outstanding as of the Closing and (iii) held by a Person (x) with a positive
amount indicated in the column "Total Unvested Obligation" opposite such
Person's EIN on Schedule 8.1 and (y) who on or before the Closing, does not
execute and deliver to ProTrader LP a Waiver shall be cancelled and all rights
in respect of such Options of the holders thereof shall terminate and be
forfeited without the receipt of any consideration in exchange for such
cancellation, termination or forfeiture.

            9) Amendment to Sections 9.8 (a)(i) and 9.8(a)(ii). Sections 9.8
(a)(i) and 9.8(a)(ii) of the Purchase Agreement are hereby amended in their
entirety to read as follows:

            (i)   Notwithstanding any other provision of this Agreement (other
than the last sentence of Section 9.10), neither Buyer nor Sellers shall have
any liability for Damages under Sections 9.1, 9.2 or 9.3, respectively, or
otherwise with respect to any breach of any representation or warranty except to
the extent that the aggregate amount of such Damages exceeds, on a cumulative
basis, $1,500,000; provided that neither Buyer nor Sellers shall be allocated
liability for claims that do not exceed $10,000 for each independent claim or
series of


                                       17
<PAGE>
related claims (including, to the extent applicable, any claims brought by one
Party against another after the $1,500,000 has be reached); provided further
that (A) with respect to any breach of any representation or warranty contained
in Section 3.4(e) (Net Capital) or Section 3.4(f) (Grigsby), or with respect to
any payment owed under Section 2.5(d), no such thresholds shall apply, (B) any
claims by Buyer with respect to items for which portions of the Purchase Price
have been escrowed pursuant to Sections 2.4(b), 2.4(c), 2.4(d), 2.4(e), 2A.4(b),
2A.4(c) and 2A.4(d) shall not be considered in determining the thresholds in
this Section 9.8(a) and no such threshold shall apply to such claims and (C) the
limitations set forth in this Section 9.8(a)(i) shall not apply to any breach of
any covenant or other agreement contained in this Agreement, including without
limitation any claims arising under Article X. In the event that a Party brings
a claim for an amount in excess of $1,500,000 (subject to the first proviso of
the first sentence of this Section 9.8(a)(i)), such Party shall be entitled to
indemnification for the full amount of all indemnified Damages (and, for
avoidance of doubt, Buyer and Sellers shall be allocated liability for any
independent or series of related claims exceeding $10,000).

            (ii)  Notwithstanding anything in this Agreement to the contrary
(other than the last sentence of Section 9.10), Sellers, on the one hand, and
Buyer, on the other, shall not have any liability to the other for Damages (on a
cumulative basis), whether pursuant to the indemnification provisions hereof or
otherwise, for any breach of any representations or warranties in excess of the
Maximum Indemnification Amount; provided that amounts paid to Buyer from the
escrow accounts maintained pursuant to Sections 2.4(b), 2.4(c), 2.4(d), 2.4(e),
2A.4(b), 2A.4(c) and 2A.4(d) shall not be subject to, nor count towards, such
$50,000,000 limit and such limit shall not apply to any breach of any
representation or warranty contained in Section 3.4(f), or to any covenant or
other agreement contained in this Agreement. The Maximum Indemnification Amount
shall be $50,000,000 (fifty million dollars); provided that, if the Indemnity
Escrow Value is less than $50,000,000 (fifty million dollars), the Maximum
Indemnification Amount shall be an amount equal to the sum of (A) one-half of
the difference between $50,000,000 and the Indemnity Escrow Value and (B) the
Indemnity Escrow Value. The Indemnity Escrow Value shall equal the sum of (A)
the amount of Cash Consideration placed in the Indemnification Escrow Account at
the Closing and (B) the product of (x) the number of shares of Instinet Common
Stock placed in the Indemnification Escrow Account at the Closing multiplied by
(y) the Instinet Share Price determined as of the day immediately following the
seventh Nasdaq trading day of January 2002.

            10) Amendment to Section 11.9(a). Section 11.9(a) of the Purchase
Agreement is hereby amended in its entirety to read as follows.

            (a)   THE AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK. 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 Supreme Court of 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, preserving,
however, all rights of removal to a federal court under 28 U.S.C. Section 1441.
Buyer hereby irrevocably designates, appoints and empowers CT Corporation
System, with offices currently at 111 Eighth Avenue, New York, New York 10011 as
its lawful agent to receive for and on its behalf service of process in the
State of New York in any such action or


                                       18
<PAGE>
proceeding. Each Seller hereby irrevocably designates, appoints and empowers
Capitol Services, with offices currently at 40 Colvin Avenue, Suite 200, Albany,
NY 12206 as its lawful agent to receive for and on its behalf service of process
in the State of New York in any such action or proceeding. Each Party
irrevocably consents to the service of process outside the territorial
jurisdiction of said courts in any such action or proceeding by mailing copies
thereof by registered United States mail, postage prepaid, to its address as
specified in or pursuant to Section 11.1. Any service made on any Party's agent
or its successor shall be effective when delivered regardless of whether notice
thereof is given to the affected Party. If any Person or firm designated as
agent hereunder shall no longer serve as agent of such Party to receive service
of process in the State of New York, the Party so affected shall be obligated
promptly to appoint a successor to so serve; and, unless and until such
successor is appointed and the other Parties notified of the same in writing,
service upon the last designated agent shall be good and effective. Each Party
hereby agrees to maintain at all times an agent to receive service of process in
the State of New York pursuant to this Section 11.9. The foregoing provisions of
this Section 11.9 shall not affect, limit or prevent any Party from serving
process in any other manner permitted by law.

            11) Amendment to Section 11.11. Section 11.11 of the Purchase
Agreement is hereby amended in its entirety to read as follows:

            11.11 Sellers' Representative

            Sellers, Young and each of their respective spouses authorize and
appoint David R. Burch as their sole representative and attorney-in-fact (the
"Sellers' Representative") for all purposes related to this Agreement, with
power to sign, on their behalf, all consents, notices, waivers, and documents
necessary or convenient for the implementation of the transactions provided
herein or related hereto including, without limitation (but only as from after
the Closing Date), all amendments hereto. Sellers, Young and each of their
respective spouses further agree that should such Sellers' Representative resign
or become unable to fulfill its role hereunder they shall exercise their best
efforts to appoint another Seller's Representative in his or her stead. Sellers,
Young and their respective spouses may at any time remove such Sellers'
Representative and appoint a replacement by providing written notice to Buyer;
provided that, the removal of such Sellers' Representative or appointment of
such replacement may be effected with the approval of any three of the Class A
Unit Holders. The Sellers' Representative shall not be liable for any action
taken by him or her in good faith except to the extent that a court of competent
jurisdiction determines that the Sellers' Representative's gross negligence or
willful misconduct was the primary cause for any loss to the Parties, or any of
them.

            12) Authorization. Each Party hereto represents to the other that
(a) such Party has all necessary corporate power and authority to enter into
this Amendment; (b) the execution and delivery by each party hereto of this
Amendment have been duly authorized by all requisite corporate action on the
part of such Party; and (c) this Amendment has been duly executed and delivered
by each Party hereto.

            13) Purchase Agreement Remains in Effect. Except as expressly
amended by this Amendment, the Purchase Agreement remains in full force and
effect and nothing in this


                                       19
<PAGE>
Amendment shall otherwise affect any other provision of the Purchase Agreement
or the rights and obligations of the Parties thereto.

            14) Counterparts. This Amendment may be executed in one or more
counterparts, each of which when executed shall be deemed to be an original but
all of which taken together shall constitute one and the same instrument.

            15) Governing Law. This Amendment shall be governed by, and
construed in accordance with, the laws of the State of New York.







                                       20
<PAGE>
IN WITNESS WHEREOF, the Parties hereto have executed and delivered this
Amendment as of the date first above written.

                                          INSTINET GROUP INCORPORATED


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


                                          OVERUNDER, LLC


                                          By:
                                             --------------------------------
                                             Name: Andrew S. Kershner
                                             Title: Sole Member


                                          -----------------------------------
                                             David G. Jamail


                                          -----------------------------------
                                             David R. Burch


                                          -----------------------------------
                                             John A. McEntire, IV


                                          -----------------------------------
                                             John Bunda


                                          -----------------------------------
                                             Laura Horne


                                          -----------------------------------
                                             Currin Van Eman


                                          -----------------------------------
                                             Shayne Young



                                       21
<PAGE>
                                 SPOUSAL CONSENT

                                 October 1, 2001

            Each of the undersigned hereby consents to the terms of the
amendment of even date herewith executed by each of their respective spouses, to
that certain Interest Purchase Agreement dated as of July 23, 2001, by and among
Instinet Group Incorporated, David G. Jamail, David R. Burch, Overunder, LLC,
John A. McEntire, IV, John Bunda, Laura Horne, Currin Van Eman and Shayne Young.
This consent may be executed in one or more counterparts, each of which shall be
deemed an original, but all of which together shall constitute one and the same
instrument.



                                                ------------------------------
                                                Phyllis Burch


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

                                                Sharon Jamail


                                                ------------------------------
                                                Lisa McEntire


                                                ------------------------------
                                                Aaron Horne


                                                ------------------------------
                                                Lynn Van Eman


                                                ------------------------------
                                                Leona Slepetis


                                                ------------------------------
                                                Amy Young




                                       22