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                                                                   EXHIBIT 10.43

                           FIRST AMENDMENT TO SUBLEASE

                  This First Amendment to Sublease (this "Amendment") dated as
of the 5th day of June, 2002 by and between CHARLES SCHWAB & CO., INC.
("Sublandlord"), having an office at 101 Montgomery Street, San Francisco,
California 94104, and INSTINET GROUP INCORPORATED ("Subtenant"), having an
office at 3 Times Square, New York, New York 10036.

                              W I T N E S S E T H:

      WHEREAS, Sublandlord, as sublandlord, and Subtenant, as subtenant, are
parties to that certain Sublease (the "Sublease"), dated as of December 18,
2001, for a portion of the Ground Floor Space, a portion of the Mezzanine Space
and the entire rentable space on floors 9, 10, 11 and 15 (being the 14th level
without regard to the Mezzanine Space, there being no 13th floor designated in
the Building) in the building known as Plaza X, Harborside, Jersey City, New
Jersey (the "Building"); and

      WHEREAS, Sublandlord and Subtenant desire to amend the Sublease as
provided in this Amendment.

      NOW, THEREFORE, in consideration of the foregoing and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, Sublandlord and Subtenant hereby agree as follows:

A.    All capitalized terms used herein without definition and defined in the
      Sublease are used herein with the meaning assigned to such terms in the
      Sublease.

B.    The Subleased Mezzanine Space shall be relocated, and there shall be
      substituted for Exhibit B to the Sublease relating to the Subleased
      Mezzanine Space a revised Exhibit B, dated May 15, 2002, relating to the
      Subleased Mezzanine Space, in the form attached hereto as Exhibit B. As a
      result of the change in the RSF of the Subleased Mezzanine Space, (i)
      there shall be substituted for Exhibit B-1 to the Sublease a revised
      Exhibit B-1, in the form attached hereto as Exhibit B-1, and (ii) there
      shall be substituted for the schedule of Subleased Mezzanine Space Fixed
      Rent Rates in Exhibit C to the Sublease a revised schedule of Subleased
      Mezzanine Space Fixed Rent Rates in Exhibit C, in the form attached hereto
      as Exhibit C.

C.    The last sentence of Section 2.1(g) of the Sublease shall be replaced by
      the following:

      "Based on such usage of the Ground Floor Space and Mezzanine Space by
      Subtenant, the parties agree that the Subleased Ground Floor Space
      constitutes 1.79% thereof, or 347 RSF of the 19,368 RSF of the entire
      Ground Floor Space and Subleased Mezzanine Space constitutes 33.04%
      thereof, or 5,436 RSF of the 16,455 RSF of the entire Mezzanine Space."

D.    In connection with the relocation of the Subleased Mezzanine Space,
      Subtenant's
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      emergency generators and certain other related equipment shall be
      relocated, and there shall be substituted for Exhibit D to the Sublease a
      revised Exhibit D (last revised April 22, 2002), in the form attached
      hereto as Exhibit D. Subtenant shall, as part of Subtenant's Work,
      construct (i) a demising wall surrounding the common generator room, (ii)
      at its sole cost and expense, a cage separating Subtenant's emergency
      generator from the remainder of the common generator room, and (iii) a
      common supply air plenum, all as shown on Exhibit D. Sublandlord shall
      reimburse Subtenant for two-thirds of the reasonable, actual,
      out-of-pocket cost of construction for the demising wall and common supply
      air plenum within thirty (30) days after receipt of a detailed invoice
      therefor. Subtenant shall use as the generator flue for Subtenant's
      emergency generator the flue as shown on such Exhibit D. Sublandlord and
      Subtenant agree to coordinate with each other in connection with the
      construction, maintenance, operation and use of the generator room and
      their respective equipment located therein.

E.    There shall be substituted for Exhibit F to the Sublease (Rest Room
      Design) a revised Exhibit F (last revised April 12, 2002), in the form
      attached hereto as Exhibit F. Subtenant hereby acknowledges and agrees
      that when the Rest Room Facilities are constructed by Sublandlord pursuant
      to Section 5(d) of the Sublease and in accordance with Exhibit F hereto,
      such Rest Room Facilities are in compliance with the Sublease and
      Subtenant shall not assert either to Sublandlord, Overlandlord or any
      Governmental Authority that same are not in compliance with Laws.

F.    There shall be substituted for Exhibit G to the Sublease (Equipment
      Location (Ground Floor)) a revised Exhibit G (last revised April 22,
      2002), in the form attached hereto as Exhibit G.

G.    INTENTIONALLY OMITTED.

H.    Sublandlord and/or its subtenants shall have the right, at its sole cost
      and expense, to use the risers designated for their use as shown on
      Exhibit L, dated April 12, 2002, in and through the Subleased Premises to
      connect communications and data transmission services in other portions of
      the Premises, provided that (i) such risers shall be concealed behind or
      within partitioning or columns and there shall be no pull boxes or other
      means of access thereto in the Subleased Premises, (ii) such risers shall
      be installed at the location(s) within the Building as shown on Exhibit L
      hereto on or before (A) as to the 9th, 10th and 11th Floors of the
      Subleased Premises, July 1, 2002, and (B) as to the 15th Floor of the
      Subleased Premises, the date which is thirty (30) days after receipt of
      notice from Subtenant of the commencement of construction by Subtenant of
      improvements on the 15th Floor of the Subleased Premises, and (iii)
      Subtenant shall not be entitled to an abatement or reduction in the
      Sublease Fixed Rent on account thereof.

I.    Subject to compliance by Subtenant with all Laws and with the terms and
      provisions of the Overlease and the Sublease, Subtenant shall have the
      right, at Subtenant's sole cost and expense, to use the risers designated
      for its use as shown on Exhibit L in and through the 12th and 14th Floors
      of the Premises (there being no 13th Floor in the Building) to connect
      Subtenant's communications and data transmission services in
      non-contiguous

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      floors of the Subleased Premises, provided that (i) such risers shall be
      concealed behind or within partitioning or columns and there shall be no
      pull boxes or other means of access thereto in the Premises other than the
      Subleased Premises, (ii) such risers shall be installed at the location(s)
      within the Building as shown on Exhibit L hereto on or before the date
      which is thirty (30) days after receipt of notice from Sublandlord or its
      subtenant of the commencement of construction by Sublandlord or its
      subtenant of improvements on the 12th and/or 14th Floors of the Premises,
      and (iii) Subtenant shall not be charged Rent for this right of access
      into and through the 12th and 14th Floor risers.

J.    Supplementing the provisions of Section 2.1(g) of the Sublease, the
      reciprocal licenses of twenty-four hour (24) hour access to the other's
      area in the Mezzanine Space and Ground Floor Space and use of commercially
      reasonable efforts not to interfere with the other's equipment in the
      Mezzanine Space and Ground Floor Space in connection with access thereto
      shall include, without limitation, caging with entrance gates or doors by
      Subtenant of Subtenant's equipment in the Subleased Mezzanine Space and
      Subleased Ground Floor Space, and caging with entrance gates or doors by
      or on behalf of Sublandlord of its equipment and that of its other
      subtenants elsewhere in the Mezzanine Space and Ground Floor Space. Each
      party may require, as a condition to such access, that, except in case of
      emergency, each party be accompanied by a representative of the other
      party (or in the case of another subtenant of Sublandlord, by a
      representative of such subtenant) who shall be made available upon
      reasonable notice. Notwithstanding the foregoing, Sublandlord and/or its
      subtenants shall have the right to install ducts, cabling, conduits and
      wiring in the Subleased Mezzanine and Ground Floor Space for horizontal
      transportation of services and utilities to the Premises, provided
      Sublandlord and its subtenants shall use commercially reasonable efforts
      not to interfere with Subtenant's equipment in the Subleased Mezzanine
      Space and Subleased Ground Floor Space.

K.    Notwithstanding the provisions of Section 5(c) of the Sublease, Subtenant
      acknowledges that Overlandlord shall not make the man-hoist available to
      Subtenant and that the man-hoist has been removed from the Building.

L.    Upon not less than thirty (30) days prior written notice from Sublandlord,
      Sublandlord shall, in Sublandlord's sole discretion, have the right to
      recapture for its own or its subtenant's use one (1) of the
      telecommunications conduits utilized by Subtenant in each of the conduit
      banks entering the Building from the North and the West, so that Subtenant
      shall only have the right to utilize three (3) such conduits in each such
      conduit bank, including the conduit bank referred to in Section 2.5(b) of
      the Sublease, as shown on Exhibits D and G. In the event Sublandlord
      exercises such right, Subtenant shall, at Subtenant's sole cost and
      expense, promptly remove all installations and wiring located therein.
      Upon such removal, the pro rata reduction in the cost to Subtenant to
      install the West bank conduits shall apply thereto, so that Sublandlord
      shall reimburse Subtenant for 1/12th of the reasonable, actual,
      out-of-pocket cost thereof within thirty (30) days after receipt of a
      detailed invoice therefor. In no event shall Subtenant be entitled to
      reimbursement of such costs for the North bank conduit.

M.    The path of travel for all of Subtenant's electrical and
      telecommunications conduits


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      located within the Mezzanine Space shall be constructed in locations to be
      mutually determined by Subtenant and Sublandlord in their commercially
      reasonable judgment. The general parameters of the locations thereof are
      shown on Exhibit D hereto. Upon final determination of the location
      thereof, such location shall be set forth on a revised exhibit to be
      prepared by Subtenant, and, upon review and approval by Sublandlord and,
      if required by the Overlease, by Overlandlord, in accordance with the
      Sublease, such exhibit shall be added to Exhibit D.

N.    Notwithstanding anything contained in Section 2.1(g) of the Sublease to
      the contrary, Subtenant shall not have, and hereby waives and
      relinquishes, the right to install a make-up water tank in the Subleased
      Mezzanine Space as referred to in Section 2.1(g) of the Sublease. That
      portion of the Subleased Mezzanine Space designated in the Sublease for
      Subtenant's make-up water tank has been exchanged for a comparable amount
      of space in the Mezzanine Space, as shown on Exhibit B attached hereto
      consisting of 360 rentable square feet (the "Substitute Space"), which
      Substitute Space shall be used in the manner otherwise permitted by the
      Overlease as incorporated into the Sublease.

O.    (i) Upon Subtenant's making the Alterations constituting a separate
      stand-by power system as contemplated by Section 5(f) of the Sublease
      (which Alteration shall constitute the respective property of Sublandlord
      and Overlandlord as provided in the Sublease and Overlease, respectively),
      the automatic transfer switch ("ATS") serving Distribution Panel 18B and
      its connections to the Building's electrical feeder to be so used to
      back-up the Building's cooling towers, condenser water pumps, heat
      exchangers, condenser water supply system, air handling units and heaters,
      all as shown on Subtenant's plans approved by Sublandlord in accordance
      with Section 5(f) of the Sublease (the "18B-ATS"), shall constitute a
      secondary portion of the back-up system, and therefore, Subtenant agrees
      may be used by Overlandlord and Sublandlord (and their other respective
      tenants and subtenants) as provided in this paragraph O, as part of any
      separate stand-by power system utilizing the Building's cooling towers
      which they may, respectively, elect to install in the Building.
      Notwithstanding such present grant of rights in and to the 18B-ATS,
      Subtenant shall have the exclusive right to use the 18B-ATS until such
      time as Overlandlord or Sublandlord shall provide written notice (the "ATS
      Notice") to Subtenant that Overlandlord or Sublandlord (or their other
      respective tenants and/or subtenants) require the use thereof for purposes
      of a separate stand-by power system. In the event Overlandlord or
      Sublandlord delivers the ATS Notice to Subtenant, Sublandlord shall pay to
      Subtenant a sum equal to the then unamortized reasonable out-of-pocket
      cost incurred by Subtenant for the 18B-ATS (exclusive of any other portion
      of Subtenant's stand-by power system), such amortization to be the period
      used for such purpose on Subtenant's books maintained in accordance with
      generally accepted accounting principles. In the event of a dispute as to
      the amount to be so paid by Sublandlord, such dispute shall be subject to
      arbitration, but shall not affect the right to use the 18B-ATS in
      accordance with the ATS Notice.

            (ii) In the event Overlandlord or Sublandlord delivers the ATS
      Notice, the management system for the Building (the "BMS") shall be
      reprogrammed by Overlandlord or Sublandlord to equitably divide the
      emergency electrical power demand

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      to the Building cooling system (including the condenser water system and
      air handling system) based upon the respective connected cooling loads of
      the parties having a stand-by power system utilizing the Building's
      cooling towers, and Subtenant shall cooperate with such reprogramming. The
      BMS shall also be so reprogrammed to determine which base building
      equipment shall be turned on when such parties' generators are operational
      and so as to cause each party's generator to operate the base building
      HVAC equipment so that power consumption from the generators is
      proportional to each party's allocated cooling capacity. Overlandlord or
      Sublandlord shall, in its commercially reasonable judgment, determine the
      power load to be allocated to each party in connection with the operation
      of their generators for emergency power based upon such parties'
      respective connected cooling load.

            (iii) Subtenant and, in the event Overlandlord or Sublandlord
      delivers the ATS Notice, Overlandlord or Sublandlord (or their other
      respective tenants or its subtenants, as applicable) shall be responsible
      for maintaining, repairing and replacing, in a commercially reasonable
      manner, its respective ATS and the connections thereto. Subtenant agrees
      that neither Overlandlord nor Sublandlord (or their other respective
      tenants or subtenants) shall have any obligation to install any such
      stand-by power system to service portions of the Premises or to operate
      such system if installed by Overlandlord or Sublandlord (or their other
      respective tenants or subtenants), nor shall Overlandlord or Sublandlord
      (or their other respective tenants or subtenants) have any liability to
      Subtenant should Overlandlord or Sublandlord (or their other respective
      tenants or subtenants) not install, repair, operate or activate such
      system, or if activated by either Overlandlord or Sublandlord (or their
      other respective tenants or subtenants) or Subtenant (or another party)
      should either or both fail to operate. Without limiting the provisions of
      the previous sentence, in the event of a failure of either ATS, the party
      with the operational ATS shall use reasonable efforts to provide emergency
      power to the Building's cooling system for the benefit of the other
      party(ies) having a stand-by power system utilizing the Building's cooling
      towers in an amount not to exceed the cooling capacity of one cooling
      tower, provided, however, neither Overlandlord nor Sublandlord (or their
      other respective tenants or subtenants) shall have any liability for
      failure of any such party to comply with the provisions of this sentence.
      In the event the cooling demand of such party exceeds such limit, the BMS
      shall be programmed to automatically decrease the cooling load available
      to the party with the non-functioning ATS. Overlandlord or Sublandlord
      shall equitably allocate the cost of operating the stand-by power system
      in accordance with each party's allocated cooling capacity. Subtenant
      hereby agrees to pay such allocated cost as Sublease Additional Charges
      within twenty (20) days after Subtenant's receipt of a bill therefor,
      accompanied by reasonably detailed back-up information.

            (iv) Overlandlord shall have the rights provided in this paragraph O
      but shall not have any obligations hereunder unless expressly assumed by
      Overlandlord in writing.

P.    Subtenant acknowledges that the security plan for the lobby of the
      Building has not been formalized as yet by Overlandlord, so that the card
      access procedures to restrict access to the lobby of the Building may or
      may not include turnstiles, and the security desk (or

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      desks) may be provided by either or both of Sublandlord and Overlandlord.

Q.    Except as otherwise expressly set forth herein, the Sublease is hereby
      ratified and confirmed and the terms, covenants, conditions and agreements
      therein contained remain in full force and effect.

R.    It is understood that any Alterations which shall be made by Subtenant
      pursuant to this Amendment, shall be subject to compliance by Subtenant
      with all Laws and with the terms and provisions of the Overlease and the
      Sublease (including, without limitation, the delivery to Overlandlord and
      Sublandlord for their approval of plans and specifications), and, except
      as may be otherwise expressly provided herein, shall be at Subtenant's
      sole cost and expense.

S.    This Amendment is subject to and conditioned upon the consent thereto by
      Overlandlord, which consent shall be evidenced by Overlandlord's signature
      appended hereto or by a separate consent in substantially the form
      utilized by Overlandlord in connection with its consent to the Sublease.



              [THE REMAINDER OF THE PAGE LEFT INTENTIONALLY BLANK]


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      IN WITNESS WHEREOF, the parties have hereunto set their hands and seals as
of the day and year first above written.

ATTEST:                                CHARLES SCHWAB & CO., INC.
                                       Sublandlord

                                    By:    /s/ Matthew D. Pearson
--------------------------              --------------------------
                                           Matthew D. Pearson
                                           Senior Vice President
                                           Corporate Real Estate & Facilities


ATTEST:                                     INSTINET GROUP INCORPORATED
                                            Subtenant

                                    By:    /s/ Frank Wallace
------------------------                --------------------------
                                            Frank Wallace
                                            Senior Vice President
                                            Corporate Services



APPROVED IN ACCORDANCE WITH AND SUBJECT TO THE TERMS AND CONDITIONS OF THAT
CERTAIN CONSENT TO SUBLEASE, DATED JANUARY 16, 2002, ISSUED BY OVERLANDLORD IN
CONNECTION WITH THE SUBLEASE.

PLAZA X LEASING ASSOCIATES L.L.C.
By: Plaza X Realty L.L.C., sole member
  By: American Financial Exchange L.L.C., sole member
         By: M-C Harsimus Partners L.L.C., member
                  By: Mack-Cali Realty, L.P., sole member
                           By: Mack-Cali Realty Corporation, general partner

                                    By:     /s/ Mitchell E. Hersh
                                        ----------------------------------------
                                            Name: Mitchell E. Hersh
                                            Title: Chief Executive Officer



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                                            Exhibit B



                                       8
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                                   Exhibit B-1

                                   EXHIBIT B-1

                   RENTABLE SQUARE FEET OF SUBLEASED PREMISES
                                  AND PREMISES
<TABLE>
<S>                                                                  <C>

15th Floor                                                            35,219 RSF
11th Floor                                                            34,099 RSF
10th Floor                                                            34,781 RSF
9th Floor                                                             34,781 RSF
Subleased Mezzanine Space                                              5,436 RSF
Subleased Ground Floor Space                                             347 RSF
Subleased Premises (total)                                           144,663 RSF
Premises                                                             594,030 RSF

</TABLE>



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                                    Exhibit C

                                    EXHIBIT C

                  [SUBLEASED MEZZANINE SPACE FIXED RENT RATES]


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                                    Exhibit D



                                       12
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                                    Exhibit F


                                       13
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                                    Exhibit G



                                       14
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                                    Exhibit L


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