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                                                                   Exhibit 10.13


                          LEASE MODIFICATION AGREEMENT

            THIS LEASE MODIFICATION AGREEMENT (the "Agreement"), dated as of
July 9, 1993, between KENVIC ASSOCIATES, having an office at 875 Third Avenue,
New York, New York 10022 ("Landlord") and INSTINET CORPORATION, a Delaware
corporation having an office at 757 Third Avenue, New York, New York 10017
("Tenant").

                              W I T N E S S E T H:

            WHEREAS, Landlord and Tenant are parties to that certain Lease (the
"Lease") dated as of November 19, 1992, between Landlord and Tenant, relating to
the entire twenty-eighth (28th) and twenty-ninth (29th) floors in the Building;

            WHEREAS, Tenant desires to lease from Landlord and Landlord desires
to lease to Tenant the entire eighteenth (18th) floor of the Building;

            WHEREAS, Landlord and Tenant desire to modify the Lease on the terms
and conditions hereinafter set forth.

            NOW, THEREFORE, in consideration of the premises, and for good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, and for the mutual agreements herein, the Lease is amended as
follows:

            1. All capitalized terms used herein without definition are defined
in the Lease.

            2. There is hereby added to the Premises the entire eighteenth
(18th) floor of the Building (the "Additional Premises"). The rentable square
foot area of the Additional Premises shall be deemed to be 28,000 rentable
square feet.

            3. A. The Additional Premises are leased for a term (the "Additional
Premises Term") which shall commence on August 1, 1993 and shall expire on the
Expiration Date unless the term shall terminate sooner pursuant to any of the
terms of the Lease or pursuant to law.

               B. Tenant acknowledges that the existing lease with "TeleRep"
covering the Additional Premises expires on July 31, 1993. Anything herein to
the contrary notwithstanding, in the event Landlord is unable to deliver all or
any portion of the Additional Premises to Tenant on August 1, 1993 as a result
of Force Majeure or the holding over of the prior tenant, Tenant shall have no
right whatsoever to cancel or terminate this Agreement (unless possession has
not been delivered to Tenant by September 1, 1993, in which event Tenant may, by
notice to Landlord given prior to the earlier of: (1) December 31, 1993 and (2)
the time

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possession is tendered to Tenant, cancel Sections 2 through 17 of this Agreement
which Sections shall, in such event be of no force or effect) and subject to the
foregoing this Agreement shall remain in full force and effect and Landlord
shall not be subject to any liability whatsoever for such inability to deliver
possession. Nothing herein shall extend the Expiration Date of the Lease.

               C. Except for Tenant's right to cancel Sections 2 through 17 of
this Agreement as set forth in Paragraph B, Tenant expressly waives any right to
rescind this Agreement or the Lease under Section 223-a of the New York Real
Property Law or under any present or future statute of similar import then in
force and further expressly waives the right to recover any damages, direct or
indirect, which may result from Landlord's failure to deliver possession of the
Additional Premises by September 1, 1993. This Section is intended to constitute
"an express provision to the contrary" within the meaning of said Section 223-a.

            4. A. The Fixed Rent payable under the Lease shall be amended as
follows:

                        (a) For each of the first five (5) years from and after
the date which is five (5) months from the date on which the Additional Premises
is actually delivered to Tenant (the "Additional Premises Rent Commencement
Date") Fixed Rent shall be increased by $767,200, per annum.

                        (b) For each year following the fifth (5th) anniversary
of the Additional Premises Rent Commencement Date until the Expiration Date,
Fixed Rent shall be increased by $879,200, per annum.

            5. Tenant's Share as defined in Article 6 of the Lease shall be
increased by 4.2% from and after the Additional Premises Rent Commencement Date.

            6. Tenant has inspected the Additional Premises and acknowledges
that the Additional Premises is in good order and repair and accepts the
Additional Premises for occupancy (including any mechanical/electrical
equipment, wherever located) in its present condition "AS IS" on the date hereof
except that Landlord shall, during the performance of Tenant's demolition work
in connection with Tenant's initial work in the Additional Premises, remove the
existing internal stairway between the 18th and 19th floors. Tenant shall
perform all work to prepare the Additional Premises for its occupancy in
accordance with the Work Letter. Landlord shall have no obligation to perform
any work in or for the Premises to prepare same for the occupancy by Tenant,
except (i) as above set forth and (ii) that, to the extent that Landlord's
representations in Section 12 are untrue, Landlord shall promptly, at its sole
cost, cure any condition resulting from such misrepresentation. Within a
reasonable period of time after the delivery to Tenant of possession of the
Additional Premises, Landlord shall at its sole cost and expense install
louvered blinds


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on the atrium glass of the Additional Premises and shall replace any missing
louvered blinds on the peripheral external windows of the Additional Premises
not delivered with the possession thereof.

            7. A. Subject to the rights of Kasowitz Hoff Benson & Torres under
its present Lease with Landlord (the "Kasowitz Lease"), if Tenant is not in
default under the Lease beyond any applicable notice and grace period, provided,
that Tenant has not subleased more than forty percent (40%) of the Premises,
Tenant shall have the option (the " 19th Floor Option") to lease from Landlord
the entire nineteenth (19th) floor (but not part thereof) (the "19th Floor").

                  B. The 19th Floor Option shall be exercisable by notice given
to Landlord no later than ninety (90) days following the Tenant's receipt of
notice from the Landlord that the Kasowitz Lease, as same may have been extended
pursuant to its terms, will expire in not more than one (1) year, but in no
event may Tenant exercise the 19th Floor Option later than March 31, 1997

                  C. If Tenant exercises the 19th Floor Option:

                        (a) Landlord shall deliver possession of the 19th Floor
to Tenant within thirty (30) days following the termination of the Kasowitz
Lease.

                        (b) Fixed Rent, as defined in Article 3 shall be
increased, as of the date of delivery to Tenant of possession of the 19th Floor,
by the greater of $712,400 or the amount determined in accordance with Section 7
(D), below for the period through the fifth (5th) anniversary of the Additional
Premises Rent Commencement Date and thereafter $816,400 or the amount determined
in accordance with Section 7 (D) below. In addition, pursuant to Section 7(C)
(c), Tenant shall also pay Additional Rent for the 19th Floor.

                        (c) Tenant's Share, as defined in Article 6 of the
Lease, shall be increased by 3.9% from and after the date of delivery to Tenant
of possession of the 19th Floor.


                  D. After Tenant has given Landlord notice of the exercise of
the 19th Floor Option, Landlord and Tenant shall seek to agree as to the
additional Fixed Rent for the 19th Floor. If they shall not agree as to such
additional Fixed Rent within thirty (30) days after Tenant exercises the 19th
Floor Option, the fair annual market rental value of the 19th Floor shall be
determined by arbitration in accordance with Section 45.04.


                        (a) If the 19th Floor is delivered to Tenant prior to
the time the additional Fixed Rent therefore has been determined, the annual
Fixed Rent thereafter payable pending such determination, shall be increased by
$712,400 (the "Temporary Rate"). In addition, pursuant to Section 7(C)(c),
Tenant shall also pay Additional Rent for the 19th Floor. Thirty (30) days


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after the determination of the fair market rental value of the 19th Floor, if
such fair market value, less the then Additional Rent allocable to the 19th
Floor exceeds the Temporary Rate, Tenant shall promptly pay Landlord the
difference for the period since possession was given Tenant; and the increase in
the Fixed Rent shall be thereafter increased to an amount not less than such
fair market rental value less the Additional Rent allocated to the 19th Floor.

                  E. If Tenant exercises the 19th Floor Option, the parties
shall immediately be bound thereby without the execution of an amendment to the
Lease; however, at the request of either party, the parties shall promptly
execute and deliver a written amendment to the Lease reflecting the addition of
the 19th Floor as part of the Premises for the remainder of the Term of the
Lease, the increase of the Fixed Rent and the increases of the Tenant's Share as
provided above, applicable to such 19th Floor. Except for such changes, the
Lease, as amended by this Agreement, shall apply with respect to the 19th Floor
and the 19th Floor shall be and become part of the Premises. Tenant shall accept
possession of the 19th Floor, and the facilities thereto and improvements
therein in the then "AS IS" condition on the date of delivery thereof to Tenant
and Landlord shall not be required to perform any work or to give Tenant any
work allowance with respect to any such space, except that all Building
Equipment serving the 19th Floor shall be in good working order. Notwithstanding
the foregoing, if Landlord is unable to deliver the 19th Floor to Tenant on the
proposed delivery date thereof as a result of Force Majeure or the holding over
of the prior tenant, Landlord shall not be subject to any liability whatsoever
for such failure or inability to deliver possession and the exercise of the 19th
Floor Option shall remain effective (unless possession has not been delivered to
Tenant within five (5) months following the expiration of the Kasowitz Lease, in
which event Tenant may, by notice given to Landlord prior to the earlier of: (1)
9 months after the expiration of the Kasowitz Lease and (2) the time possession
is tendered to Tenant, cancel the 19th Floor Option). Nothing herein shall
operate to extend the Expiration Date for any of the Premises (including but not
limited to the 19th Floor) beyond the date otherwise fixed therefor in the
Lease.

            Time shall be of the essence with respect to the Tenant's exercise
of the 19th Floor Option, and the time period for the exercise of such option
shall not be extended for any reason. If Tenant shall fail to exercise the 19th
Floor Option, Tenant's rights with respect thereto shall wholly cease, terminate
and expire, and Tenant shall upon request of Landlord confirm such nonexercise
in writing, but failure to do so by Tenant shall not operate to revive any
rights of Tenant under this Section.

            Nothing in this Section shall be construed (a) to obligate Landlord
to refuse its consent to any proposed sublease for a term less than the then
remaining term of the Kasowitz Lease or assignment of the Kasowitz Lease by a
tenant in possession of any portion of the 19th Floor; or (b) to obligate
Landlord to evict


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a tenant of the 19th Floor which is in default under the Kasowitz Lease (but
Landlord shall, at Landlord's cost and expense, commence and prosecute holdover
proceedings against the tenant of the 19th Floor after the Kasowitz Lease has
expired if Tenant has theretofore exercised the 19th Floor Option).

            Except for the Tenant's right to cancel the 19th Floor Option as set
forth above, Tenant expressly waives any right to rescind this Agreement or the
Lease under Section 223-a of the New York Real Property Law or under any present
or future statute of similar import then in force and further expressly waives
the right to recover any damages, direct or indirect, which may result from
Landlord's failure to deliver possession of the 19th Floor on the commencement
date with respect to the 19th Floor. This Section is intended to constitute "an
express provision to the contrary" within the meaning of said Section 223-a.

            8. Section 22.09 of the Lease is amended by changing "14,500" in the
fourth line to "21,750."

            9. Section 31.02 of the Lease is amended by changing "fifty (50)" in
the sixth line to "seventy-five (75)".

            10. Section 15.02 of the Lease shall be amended to deem the total
damage or the rendering wholly untenantable of the Trading Floor to be the
equivalent of a total damage or rendering wholly untenantable of the Premises.
The "Trading Floor" shall be defined as the twenty-ninth (29th) floor so long as
such floor is the principal site of Tenant's trading operations. Tenant shall
promptly notify Landlord if the Trading Floor is moved from the twenty-ninth
(29th) floor.

            11. Landlord covenants that Landlord will modify the elevator cabs
of the Building so that such elevator cabs are in compliance with The Americans
with Disabilities Act.


            12. REPRESENTATIONS AND WARRANTIES. Landlord represents, warrants
and covenants that:


                  (a) The Additional Premises has and will have available upon
delivery of the Additional Premises at least 50 nominal tons of air conditioning
capacity and six (6) nominal tons of supplemental air conditioning capacity.
Landlord represents that the Building Equipment which serve the Additional
Premises shall be in working order on the date possession of the Additional
Premises shall be given to Tenant.

                  (b) There are and will be upon delivery of the Additional
Premises two (2) electric closets and risers in the Additional Premises, each of
which contains a 200 amp disconnect switch served by electric conduit of and
fused at 175 amps capacity. All power is 480 volts, 3 phase.


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                (c) No asbestos was used in the construction of the Additional
Premises, the 19th Floor or the improvements thereon installed by Landlord.

            13. Section 10.10 of the Lease is amended by adding "or the
Additional Premises or the 19th Floor" after "Premises" on line four.


            14. (a) If Tenant's equipment in the Additional Premises exceeds the
Building's air conditioning capacity, as represented in Section 12 (a), Tenant
shall at Tenant's cost provide any necessary supplemental air conditioning
capacity, and, may at Tenant's expense, vent cooling air from supplemental air
conditioners through louvers in peripheral windows on the easterly side of the
Building at a location to be mutually agreed upon by Landlord and Tenant.


                (b) Landlord shall make available to Tenant a 400 amp switch in
Landlord's electric frame room to supply power to Tenant's existing supplemental
riser to floors 28 and 29, which riser may also be tapped to serve the
Additional Premises and the 19th Floor, if the 19th Floor Option is exercised.

            15. Section 3.03 of the Lease is amended by adding "or the
Additional Premises or the 19th Floor under the Lease Modification Agreement"
after "Article 47" on line 18. And adding the following sentence to the end of
said Section 13.03: "Notwithstanding anything to the contrary contained herein,
Tenant shall in connection with Tenant's initial work for the Additional
Premises and/or the 19 Floor have the right to install no more than two (2)
additional four (4) inch conduits between the Additional Premises and the twenty
eighth (28th) floor communications room through Telephone Closet "A", to
accommodate its communication requirements subject only to the capacity of riser
cabinets and conduits. In addition, Tenant shall have the right to install
additional communications risers, subject to availability and Landlord's
approval, not to be unreasonably withheld or delayed.

            16. Section 14.03 of the Lease is amended by adding "in each of the
twenty-eighth/twenty-ninth floor space and the Additional Premises" after
"bathroom shower" on line four.

            17. Lines 10 and 11 of Section 16.02 of the Lease are amended by
substituting the words "Five Million Four Hundred Sixty Thousand Dollars
($5,460,000)" for the words "Three Million Five Hundred Thousand Dollars
($3,500,000) ."

            18. Article 36 of the Lease is amended by adding the following new
Section 36.02:

            Section 36.02. Wherever Tenant is required to procure an irrevocable
letter of credit to insure its performance under the Lease or that of a
subtenant under a sublease, the following shall apply:


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                  A. If the letter of credit is required pursuant to Section
22.04 Landlord may draw upon such letter of credit if the Tenant is in default
beyond all applicable notice and cure periods or has not renewed such letter of
credit in accordance with Section 36.01; provided, however, that in addition to
a sight draft in the form set forth in Exhibit G, Landlord shall also present a
statement in substantially the form of (a) or (b) set forth below:

                        (a) "Tenant is in default under the Lease beyond all
            applicable notice and cure periods"; or

                        (b) "Tenant has failed to comply with the provisions of
            Section 36.01 and has not renewed the letter of credit forty-five
            (45) days prior to its expiration date".

                  B. If Tenant delivers the letter of credit pursuant to Section
22.06(c)(i), drawings under such letter of credit shall be permitted as follows:

                  (i) If Tenant is in default under this Lease beyond all
applicable notice and cure periods and subtenant is in possession of the
Premises and is also in default under the sublease, then Landlord may draw upon
the letter of credit by accompanying Landlord's sight draft with the following
statement:

                        "Tenant is in default under the Lease beyond all
                  applicable notice and cure periods and subtenant is in
                  possession of the Premises and is also in default under the
                  sublease beyond all applicable notice and cure periods."

                  (ii) If Tenant is not in default under this Lease beyond all
applicable notice and cure periods, but subtenant is in default under the
sublease, then if

            (x) Tenant provides Landlord with a substitute letter of credit in
            substantially the same form as the existing letter of credit which
            Landlord holds as security, Landlord shall assign its interest as
            beneficiary under the original letter of credit to Tenant. If, after
            the assignment of the original letter of credit, subtenant remains
            in default, Tenant may draw upon the original letter of credit as
            agreed between Tenant and the subtenant pursuant to the sublease. If
            Tenant evicts the subtenant from the Premises, and Tenant is not
            then in default beyond all applicable notice and cure periods under
            this Lease, Landlord shall return the substitute letter of credit to
            Tenant. In the event Tenant draws upon the letter of credit Tenant's
            sight draft must be accompanied by the following statement:


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                        "Subtenant is in possession of the Premises and is in
                  default under the sublease beyond all applicable notice and
                  cure periods".

            (y) Tenant does not issue a substitute letter of credit pursuant to
            Paragraph B (ii) (x) above, Landlord shall draw upon the letter of
            credit and hold the funds as security against subtenant's default or
            a potential default by Tenant. If Tenant is not then in default at
            the time of the removal of the subtenant from the Premises, upon
            Tenant's request, proceeds of the letter of credit will be applied
            against any sums owing to Tenant by subtenant as a result of its
            default under the sublease. Tenant shall indemnify Landlord for any
            loss, cost or damage, including attorneys' fees and disbursements
            associated with any claim by subtenant which relates to such
            proceeds, provided; however, Tenant shall not have any obligation to
            indemnify Landlord for its gross negligence with respect to any
            loss, cost or damage. If Landlord draws upon the letter of credit
            Landlord's sight draft must be accompanied by the following
            statement:


                        "Subtenant is in possession of the Premises and is in
                  default under the sublease beyond all applicable notice and
                  cure periods."


                  (iii) If the letter of credit has not been renewed forty-five
(45) days prior to its expiration, then Landlord may draw upon the letter of
credit and hold the proceeds as security against any potential defaults by
Tenant or the subtenant, as the case may be. Tenant shall indemnify Landlord for
any loss, cost or damage, including attorneys' fees and disbursements,
associated with any claim by subtenant which relates to such proceeds, provided;
however, Tenant shall not have any obligation to indemnify Landlord for its
gross negligence with respect to any loss, cost or damage associated with
holding such funds. To draw upon the letter of credit Landlord must accompany
the sight draft with the following statement:


                        "Subtenant has the right to possession of the Premises
                  and the letter of credit has not been renewed in accordance
                  with the terms of the sublease and the Lease forty-five (45)
                  days prior to its expiration date."


                  C. If Tenant delivers a letter of credit in accordance with
Section 22.10.1, Landlord may draw upon the letter of credit if the Tenant is in
default beyond all applicable notice and cure periods or has not renewed the
letter of credit in accordance with Article 36; provided, however, that in
addition to


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a sight draft Landlord shall present a statement in either the form of (a) or
(b) set forth below:


                        (a) "Tenant is in default under the Lease beyond all
                  applicable notice and cure periods;" or



                        (b) "Tenant has failed to comply with the provisions of
                  Article 36 of the Lease and has not renewed the letter of
                  credit forty-five (45) days prior to its expiration date."


                  D. Notwithstanding anything contained in the Lease, if
subtenant is not in default under the sublease and the subtenancy terminates and
subtenant vacates the Premises, Landlord shall return to Tenant any letter of
credit issued pursuant to Article 22 (provided Landlord has not drawn on such
letter of credit) and Tenant shall have no continuing liability related thereto.
However, in the event subtenant is in default under the sublease upon the
termination of its subtenancy, Landlord may draw upon the letter of credit as
set forth in this Lease.

            Each letter of credit issued pursuant to Article 22 shall operate as
a separate and distinct instrument and may be drawn upon individually in
accordance with this Lease.

            19. Tenant represents that in the negotiation of this Agreement it
dealt with no broker(s) other than The Peregrine White Company, Inc. (the
"Broker") and no other broker participated in bringing about this Agreement.
Tenant hereby indemnifies and agrees to defend and hold Landlord harmless
against any claim or liability arising out of any inaccuracy or alleged
inaccuracy of the above representation. The parties hereto acknowledge that the
Broker will be paid a commission in accordance with a separate agreement.
Landlord represents that to the best of Landlord's knowledge, it has not dealt
with any broker other than the Broker in connection with this Agreement.

            20. This Agreement shall not be effective unless the consent of John
Hancock Life Insurance Company ("Hancock") to this Agreement has been obtained
and a new nondisturbance agreement in the form annexed as Exhibit A is delivered
to Tenant. Landlord shall, within thirty (30) days after the execution and
delivery of this Agreement by Landlord and Tenant, obtain any required consent
and the new nondisturbance agreement from Hancock. If Hancock does not grant
such required consent and deliver the new nondisturbance agreement within said
thirty (30) day period, then Tenant shall have the right to cancel this
Agreement by written notice to Landlord and upon such notice (provided Hancock
shall not have therefore consented to this Agreement and executed and delivered
to Tenant the new nondisturbance agreement) this Agreement shall be of no force
or effect and the Lease shall remain in full force and effect. If Hancock does
not grant any required consent and deliver the new nondisturbance agreement
within sixty (60) days after the


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execution and delivery of this Agreement by Landlord and Tenant, then Landlord
shall have the right to cancel this Agreement by notice to Tenant, and upon such
notice (provided Hancock shall not have therefore consented to this Agreement
and delivered to Tenant the new nondisturbance agreement) and this Agreement
shall be of no force and effect and the Lease shall remain in full force and
effect.


            21. Except as modified by this Agreement, the Lease shall remain in
full force and effect in accordance with its terms and is hereby ratified and
confirmed.


            22. This Agreement shall be binding on and shall inure to the
benefit of the parties hereto and their respective successors and permitted
assigns.

            23. Anything herein to the contrary notwithstanding, Landlord may at
any time on ninety (90) days notice to Tenant, install and maintain a mail
conveyor through the Additional Premises in the area marked by cross hatching on
Exhibit B. Such work shall be performed in a good and workerlike manner, in
accordance with all Legal Requirements and shall be completed expeditiously with
minimum interference to Tenant's operations. Landlord shall promptly repair any
damage and restore the remainder of the Additional Premises to its condition
immediately prior to the performance of such work. Landlord shall defend,
indemnify, and hold Tenant harmless for any loss, cost or damage, including but
not limited to reasonable attorney's fees, costs and disbursements sustained by
Tenant as a result of the performance of such work by Landlord.


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            IN WITNESS WHEREOF, the parties have caused this Agreement to be
executed as of the date first above written.

                                          LANDLORD:

                                          KENVIC ASSOCIATES:

WITNESS:


/s/                                       By: /s/ Lucille Gladstone
----------------------------------            ----------------------------------
                                              Name: Lucille Gladstone
                                              Title: Partner



                                          TENANT:

                                          INSTINET CORPORATION

WITNESS:


/s/                                       By: /s/ Charles R. Hood
----------------------------------            ----------------------------------
                                              Name: Charles R. Hood
                                              Title: Senior Vice President



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                           LANDLORD'S ACKNOWLEDGEMENT

STATE OF NEW YORK       )
                        : ss.:
COUNTY OF NEW YORK      )

            On this 9th day of July, 1993, before me personally came Lucille
Gladstone, to me known, who, being by me duly sworn, did depose and say that she
is a partner in the firm of KENVIC ASSOCIATES, a New York partnership, and that
she executed the foregoing instrument as and on behalf of said partnership.


                                        /s/ Barry M. Bernstein
                                        ----------------------------------------
                                        Notary Public

                                                     BARRY M. BERNSTEIN
                                              Notary Public, State of New York
                                                       No. 31-4698293
                                                Qualified in New York County
                                            Commission Expires November 30, 1993

                       CORPORATE TENANT'S ACKNOWLEDGEMENT

STATE OF NEW YORK       )
                        : ss.:
COUNTY OF NEW YORK      )

            On this 8th day of July, 1993, before me personally came Charles R.
Hood, to me known, who, being by me duly sworn, did depose and say that he
resides at 60 Pineapple Street, Apartment 4H, Brooklyn Heights, New York 11201;
that he is the Senior Vice President of Instinet Corporation, the corporation
described in and which executed the foregoing Lease, as Tenant, and that he
signed his name thereto by order of that corporations' board of directors.


                                        /s/ Brian P. Lyons
                                        ----------------------------------------
                                        Notary Public

                                                       BRIAN P. LYONS
                                              Notary Public, State of New York
                                                       No. 41-4945353
                                                 Qualified in Queens County
                                            Commission Expires December 19, 1994


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