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Lease No.

                         ROCKEFELLER CENTER PROPERTIES,

                                                     Landlord,

                                       TO

                            JOHN A. LEVIN & CO., INC.

                                                       Tenant.

                                   ----------

                                      Lease

                             Dated December 20, 1993

                                   ----------

                              One Rockefeller Plaza           Building

                          ROCKEFELLER CENTER PROPERTIES
                           1230 AVENUE OF THE AMERICAS
                              NEW YORK. N.Y. 10020

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                                TABLE OF CONTENTS

Demise of Premises, Term and Rent .........................................    1

Completion and Occupancy ..................................................    2

Use of Premises ...........................................................    3

Fixtures ..................................................................    4

Electric Current and Water ................................................    5

Various Covenants .........................................................    6

Assignment, Mortgaging, Subletting, etc ...................................    9

Changes or Alterations by Landlord ........................................   13

Damage by Fire, etc .......................................................   14

Condemnation ..............................................................   15

Compliance with Laws ......................................................   16

Accidents to Sanitary and other Systems ...................................   17

Subordination .............................................................   17

Notices ...................................................................   19

Conditions of Limitation ..................................................   19

Re-entry by Landlord ......................................................   20

Damages ...................................................................   21

Waivers by Tenant .........................................................   22

Tenant's Removal ..........................................................   22

Elevators, Cleaning, Services, etc ........................................   22

Lease Contains All Agreements-No Waivers ..................................   24

Parties Bound; Exculpation ................................................   24

Curing Tenant's Defaults-Additional Rents .................................   25

Adjustments for Changes in Landlord's Costs and Expenses ..................   26

Miscellaneous .............................................................   30

Security ..................................................................   32

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Brokerage Commission ......................................................   33

Quiet Enjoyment ...........................................................   33

Hazardous Substances ......................................................   33

Work by Tenant ............................................................   34

Sprinklers ................................................................   35

Asbestos Removal by Tenant ................................................   36

Termination by Tenant .....................................................   37

Extra Space ...............................................................   37

Assignment of Lease .......................................................   38

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RCP-L(1/92)
GTS:VL

                                                                          [LOGO]

      Lease, dated December 20, 1993, between ROCKEFELLER CENTER PROPERTIES, a
partnership, having an office at 1230 Avenue of the Americas, New York, N.Y.
10020 (the "Landlord"), and JOHN A. LEVIN & CO., INC., a Delaware corporation,
having an office at One Rockefeller Plaza, New York, N.Y. 10020 (the "Tenant"),

                                   Witnesseth:

                                   ARTICLE ONE
                        Demise of Premises, Term and Rent

      1.1. The Landlord does hereby lease and demise to the Tenant, and the
Tenant does hereby hire and take from the Landlord, subject and subordinate to
the Qualified Encumbrances (as hereinafter defined) and upon and subject to the
provisions of this Lease, for the term hereinafter stated, the space(s)
substantially as shown hatched on the diagram(s) attached hereto as Exhibit A
and designated as 'A' on the 25th Floor of the building known as One Rockefeller
Plaza (the "Building"), situated upon a plot of land (the "Land"), and
comprising a part of Rockefeller Center (the "Center"), in the Borough of
Manhattan, New York, N.Y., together with all fixtures, equipment, improvements,
installations and appurtenances which at the commencement of or during the term
of this Lease are thereto attached (except items not deemed to be included
therein and removable by the Tenant as provided in Article Four); which
space(s), fixtures, equipment, improvements, installations and appurtenances are
sometimes called the "Premises".

      1.2. The term of this Lease shall commence on October 1, 1994 (subject to
Article Two, such date for the commencement of the term of this Lease being the
"term commencement date") and shall end on September 30, 2004 or on such earlier
date upon which the term may expire or be terminated pursuant to any of the
conditions of limitation or other provisions of this Lease or pursuant to law.

      1.3. The Premises may be used for the following, but no other, purposes,
namely: executive, administrative, general, sales and clerical offices of a
corporation or other entity engaged in investment management and related
activities or for any other business or businesses which are not prejudicial to
the reputation of, or reflect unfavorably on, the Center so as to detract from
it as a location for an outstanding type of business occupancy, including
activities incidental thereto.

      1.4. The rent reserved under this Lease for the term of this Lease shall
consist of (a) fixed rent, at the following rate(s), namely: $526,008.00 per
annum commencing on the term commencement date and ending on September 30, 1999;
and $593,880.00 per annum thereafter payable in equal monthly installments in
advance on the first day of each and every calendar month of the term of this
Lease for which fixed rent is reserved as aforesaid (except that, if the term
commencement date shall be other than the first day of a calendar month, the
first monthly installment of fixed rent, apportioned for the part month in
question, shall be payable on the term commencement date and except that the
Tenant shall pay, upon the execution of this Lease by the Tenant, $43,834.00 to
be applied against the first installment or installments of fixed rent coming
due hereunder), plus (b) the additional rent payable as provided in this Lease;
all to be paid to

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the Landlord, at its office as set forth above, or at such other place or places
as the Landlord shall designate to the Tenant, in lawful money of the United
States of America; provided, however, that, notwithstanding the foregoing, the
fixed rent payable hereunder shall be abated in the aggregate amount of
$743,706.00, which said abatement shall be applicable to the first installment
or installments of fixed rent becoming due hereunder.

      1.5 The Tenant shall pay the fixed rent and additional rent (collectively
"Rent") as and when the same shall become due and payable as provided in this
Lease, without demand therefor, and without any setoff or deduction whatsoever
except as expressly otherwise provided herein, and keep, observe and perform,
and permit no violation of, each and every provision contained in this Lease on
the part of the Tenant to be kept, observed and performed.

      1.6 In determining the rentable area and, where applicable, the useable
area of any building in the Center or any portion thereof pursuant to any
provision of this Lease, the rentable area or useable area of such building or
such portion, as the case may be, shall be the rentable area or useable area
thereof in square feet determined in accordance with the Standard Method of
Floor Measurement for Office Buildings approved by The Real Estate Board of New
York, Inc., which became effective on January 1, 1987, assuming a 20% loss
factor from rentable to useable. The parties agree that as of the date hereof
the Premises contain 16,968 rentable square feet.

      1.7 The term "Qualified Encumbrances" means (a) matters of record
affecting the Premises, Building or Land on the date of this Lease or hereafter
approved by the Tenant, which approval shall not be unreasonably withheld, (b)
the underlying mortgages and underlying leases to which this Lease is
subordinate pursuant to Article Thirteen, (c) any declaration of restrictions or
other document in respect of the transfer of use of development rights, (d) any
declaration or other document which subjects all or any portion of the Land
and/or the Building to a condominium regime, and (e) any preservation or similar
easement, declaration or agreement containing covenants, restrictions or
agreements in respect of the maintenance of the Building and/or the Land as a
landmark site with or held by a governmental agency or an entity designated or
accepted by a governmental agency (each, a "Preservation Agreement").

                                   ARTICLE TWO
                            Completion and Occupancy

      2.1. The Tenant has examined and shall accept the Premises in their
existing condition and state of repair and understands that no work is to be
performed by the Landlord in connection therewith except the work the Landlord
is required to do by the terms of this Lease. The Landlord, either through its
own employees or through a contractor or contractors to be engaged by it for
such purpose, will proceed with due dispatch, subject to delay by causes beyond
its reasonable control, Tenant Delay (as hereinafter defined) and the failure of
any present occupant of the Premises to vacate and surrender the same, to do all
of the work during regular working hours and will exercise all reasonable
efforts to complete all of such work not later than the specific date
hereinabove designated for the commencement of the term of this Lease. If the
Landlord is required by this Lease to do any such work without expense to the
Tenant and the cost of such work is increased due to any Tenant Delay, the
Tenant shall pay to the Landlord an amount equal to such increase in cost.

      2.2. Unless otherwise specifically provided in this Lease, if any of the
space demised hereunder and constituting the Premises shall not be available for
possession by the Tenant on the specific date hereinabove designated for the
commencement of the term with respect to such space for any reason, including,
without limitation, the continued occupancy in a portion of the Premises by a
current subtenant thereof, then this Lease shall not be affected thereby but, in
such case, the term commencement date with respect to such space only shall be
postponed until the date when such space shall be available for possession by
the Tenant, provided, that there shall be no such postponement of the term
commencement date with respect to any portion of the Premises the Landlord shall
deliver possession of to the Tenant or for any delay in the availability of any
space in the Premises for possession by the Tenant which shall be due to (a) any
act or omission of the Tenant, any affiliate thereof or their respective agents,
officers, partners, directors, contractors, employees, licensees or invitees,
including,

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without limitation, delays due to changes in or additions to any work to be done
by the Landlord or delays in submission of information, approving working
drawings or estimates or giving authorizations or approvals ("Tenant Delay"), or
(b) the noncompletion by the Landlord of any work, whether in connection with
the layout or finish of any space in the Premises or otherwise, which the
Landlord is not required to do by the terms of this Lease until after the term
commencement date; it being understood that the Tenant shall have no claim
against the Landlord, and the Landlord shall have no liability to the Tenant, by
reason of any such postponement of said specific date. No part of the Premises
shall be deemed unavailable for possession by the Tenant, nor shall any work
which the Landlord is obligated to perform in such part of the Premises be
deemed incomplete for the purpose of any adjustment of fixed rent payable under
this Lease, solely due to the noncompletion of details of construction,
decoration or mechanical adjustments which are minor in character and the
noncompletion of which does not materially interfere with the Tenant's use of
such part of the Premises. Subject to the foregoing, the parties to this Lease
expressly provide that, if any of the space demised hereunder and constituting
the Premises is not available for possession by the Tenant on the specific date
hereinabove designated for the commencement of the term with respect to such
space, the Tenant, except with the consent of the Landlord, shall not be
entitled to possession of such space until the same is delivered to the Tenant
by the Landlord and there shall be no abatement of rent by reason thereof, and
the Tenant shall not have any claim against the Landlord nor any right to
rescind this Lease, and the Landlord shall have no liability to the Tenant, by
reason thereof The foregoing Section 2.2 shall constitute "an express provision
to the contrary" as such phrase is used in Section 223-a of the Real Property
Law of the State of New York and shall constitute a waiver of the Tenant's
rights pursuant to such Section 223-a and any other law of like import now or
hereafter in force.

      2.3. The Tenant by taking possession of any part of the Premises shall be
conclusively deemed to have agreed that the Landlord, up to the time of such
possession, had performed all of its obligations under this Lease with respect
to such part and that such part, except for latent defects and except for minor
details of construction, decoration and mechanical adjustment referred to above,
was in satisfactory condition as of the date of such possession.

                                  ARTICLE THREE
                                 Use of Premises

      3.1. The Tenant shall not, except with the prior consent of the Landlord,
use, or suffer or permit the use of, the Premises or any part thereof for any
purpose other than the uses permitted in Article One, provided, that the
portions, if any, of the Premises which are identified as toilets or utility
areas shall be used by the Tenant only for the purposes for which they are
designed and the portions, if any, of the Premises which are identified as
storage areas shall be used only for storage purposes.

      3.2. The Tenant shall not use, or suffer or permit the use of, the
Premises or any part thereof in any manner or for any purpose or do, bring or
keep anything, or suffer or permit anything to be done, brought or kept, therein
(including, without limitation, the installation or operation of any electrical,
electronic or other equipment) which (i) would violate any provision of this
Lease or is unlawful or in contravention of the Certificate of Occupancy for the
Building, or (ii) in the reasonable judgment of the Landlord may in any way
impair or interfere with any of the Building services or the proper and economic
heating, air conditioning, cleaning or other servicing of the Building or the
Premises or impair or interfere with the use of any of the other areas of the
Building by, or occasion discomfort, inconvenience or annoyance to, any other
tenant of the Building or the Center or impair the appearance of the Building;
nor shall the Tenant use, or suffer or permit the use of, the Premises or any
part thereof in any manner, or do, or suffer or permit the doing of, anything
therein or in connection with the Tenant's business or advertising which, in the
reasonable judgment of the Landlord, may be prejudicial to the business of the
Landlord or the reputation of the Landlord, the Building or the Center or
reflect unfavorably on the Landlord, the Building or the Center or confuse or
mislead the public as to any connection or relationship between the Landlord and
the Tenant.

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      3.3. Unless otherwise specifically provided in this Lease, the Tenant will
not use, or suffer or permit the use of, the Premises or any part thereof for
any of the following purposes, whether or not incidental to the Tenant's
business, namely: (a) manufacturing of any kind, (b) broadcasting or the
business of broadcasting by wire or wireless of any programs or pictures of any
sort, or for the sale of apparatus or devices connected with the business of
such broadcasting, (c) the retail sale of any item whatsoever, (d) an auction of
any kind, or (e) the preparation, dispensation or consumption of food or
beverages, except, that parts of the Premises may be used as a pantry and
lunchroom for employees of the Tenant and for the installation and operation of
food and beverage vending machines upon the condition in each case that (1) no
cooking or other preparation of food (other than the preparation of beverages
and heating of prepared food) shall be done in the Premises, (2) no food or
beverages will be kept or served in the Premises in a manner or under any
conditions which shall be the occasion for fumes or odors being emitted from, or
detectable outside of, the Premises, (3) such parts of the Premises shall be at
all times maintained by the Tenant in a clean and sanitary condition and free of
refuse (including use of extermination services whenever required), and (4) the
Tenant will keep the plumbing and sanitary systems and installations serving
such parts of the Premises to the points they connect with the main vertical
risers and stacks of the Building in a good state of repair and operating
condition.

      3.4. If any governmental license or permit shall be required for the
proper and lawful conduct of any business or other activity carried on in the
Premises and, if the failure to secure such license or permit would, in any way,
affect the Landlord, the Tenant shall promptly procure and thereafter maintain
such license or permit, submit the same to inspection by the Landlord, and
comply with the terms and conditions thereof.

      3.5. Neither the Tenant nor any occupant of the Premises shall use the
words "Rockefeller", "Center" or "Radio City", or any combination or simulation
thereof, for any purpose whatsoever, including (but not limited to) as or for
any corporate, firm or trade name, trademark or designation or description of
merchandise or services, except that the foregoing shall not prevent the use, in
a conventional manner and without emphasis or display, of the words "Rockefeller
Center" and/or, where applicable, "Rockefeller Plaza" as part of the Tenant's
business address. Neither the Tenant nor any occupant of the Premises shall use
the name of the Building or the name of the entity for which the Building is
named or any part or abbreviation (including initials) of either such name
except that the foregoing shall not prevent the use of the name of the Building
or any part thereof, in a conventional manner and without emphasis or display,
as a part of the Tenant's or such occupant's business address or by reference in
the ordinary course of its business.

                                  ARTICLE FOUR
                                    Fixtures

      4.1. All fixtures, equipment, improvements and installations ("Fixtures")
attached to, or built into, the Premises at the commencement of or during the
term of this Lease, whether or not installed at the expense of the Tenant or by
the Tenant, shall be and remain part of the Premises and be deemed the property
of the Landlord and shall not be removed by the Tenant except as otherwise
expressly provided in this Lease. All electric, plumbing, heating, sprinkling,
dumbwaiter, elevator, fixtures and outlets, venetian blinds, partitions,
railings, gates, doors, vaults, stairs, paneling (including display cases and
cupboards recessed in paneling), molding, shelving, radiator enclosures, floors,
and ventilating, silencing, air conditioning and cooling equipment shall be
deemed to be included in Fixtures, whether or not attached to or built into the
Premises. Notwithstanding the foregoing, Tenant shall (i) close up any slab
penetration in the Premises made by or on behalf of the Tenant and (ii) remove
from the Building all Fixtures furnished and installed in any part of the
Premises by or on behalf of the Tenant (whether or not attached thereto or built
therein) at the sole expense of the Tenant (and with respect to which no credit
or allowance shall have been granted to the Tenant by the Landlord), as well as
any safes, vault areas, lead-lined rooms, conveyors, pneumatic tubes, internal
elevators, and mechanical and electrical rooms and telephone switchrooms
furnished or installed by or on behalf of the Tenant and the equipment therein;
provided that the Tenant shall not be required to remove Fixtures furnished and
installed in replacement of an item for which Tenant neither paid nor received a
credit or allowance. All such closing and removal shall be performed not later
than the expiration or termination of the Lease and shall be performed subject
to the provisions of this

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Lease, including, without limitation, subsection (e) of Article Six. The Tenant
shall repair any damage to the Premises arising from such closing and removal
described in the preceding sentence. The cost of repairing any damage to the
Premises or the Building arising from such closing and removal described in the
preceding sentences shall be paid by the Tenant upon demand. If any Fixture
which as aforesaid may or is required to be removed by the Tenant is not so
removed within the time above specified therefor, then the Landlord may at its
election deem that the same has been abandoned by the Tenant to the Landlord,
but no such election shall relieve the Tenant of its obligation to pay the cost
and expense of removing the same or the cost of repairing damage arising from
such removal. Notwithstanding the foregoing, the Landlord may, by notice to the
Tenant, prohibit the closing of any slab penetration not theretofor closed and
the removal of any or all items the Tenant is required to remove pursuant to
this Section 4.1 but has not theretofor removed.

      4.2. All the perimeter walls of the Premises, any balconies, terraces or
roofs adjacent to the Premises (including any flagpoles or other installations
on said walls, balconies, terraces or roofs), and any space in and/or adjacent
to the Premises used for shafts, stairways, stacks, pipes, conduits, ducts, mail
chutes, conveyors, electric or other utilities, sinks, fans or other Building
and Center facilities, and the use thereof, as well as access thereto through
the Premises (at and for such times as shall not unreasonably interfere with the
Tenant's business) for the purposes of such use and the operation, improvement,
replacement, addition, repair, maintenance or decoration thereof, are expressly
reserved to the Landlord.

                                  ARTICLE FIVE
                           Electric Current and Water

      5.1. The Landlord shall furnish, through the existing transmission
facilities installed by it in the Building, alternating electric current to the
electric closets and panels provided by the Landlord and serving the Premises in
such reasonable quantity as may be required for the Tenant's ordinary use of the
Premises for the purposes herein specified, but such quantity shall not exceed,
in the aggregate, an average of four watts per useable square foot of space in
the Premises. Such alternating electric current shall be measured by a meter or
meters provided and installed by the Landlord at such location or locations as
the Landlord shall select, it being understood that Tenant is responsible for
installation of meter service, including, without limitation, CT cabinets, meter
pans and associated wiring, but excluding the meter itself. The Tenant shall pay
to the Landlord, as billed by the Landlord, at the end of each billing period of
the public utility company then supplying such alternating electric current to
the Center an amount which shall be the sum of (i) 109% of the product obtained
by multiplying the actual number of kilowatt hours of electric current consumed
by the Tenant in such billing period by a fraction having as its numerator the
amount charged the Landlord for the Center by said public utility for the total
number of kilowatt hours billable to the Landlord for the Center's tenants' use
in such billing period and as its denominator said total number of kilowatt
hours plus (ii) any sales, use or other similar taxes applicable to the amount
determined pursuant to the foregoing clause (i). In any circumstances where any
meter measures consumption of electricity by more than one tenant, the Landlord
shall make a reasonable estimate of such consumption and allocate the cost
thereof pro rata to the tenants (including the Tenant) which derive the benefit
thereof in accordance with the respective rentable areas occupied by such
tenants and subject to such shared metering.

      5.2. The Landlord may, at its option, upon not less than thirty (30) days'
prior notice to the Tenant, discontinue the furnishing of electric current to
the Premises or any part thereof and, in such event, the Tenant shall contract
for the supplying of such electric current thereto with the public service
company supplying electric current to the neighborhood. It being understood that
the Landlord will not discontinue, except where otherwise mandated by any
Requirements (as hereafter defined), the furnishing of such electric current to
the Premises until the Tenant has had a reasonable time to contract for the
furnishing of such electric current with such public service company; provided,
however, that the Tenant proceeds in a diligent manner with respect to such
conversion. The Landlord shall permit its risers, conduits and feeders serving
the Premises, to the extent available, suitable and safely capable, to be used
for the purpose of supplying such electric current.

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      5.3. If the Tenant shall require electric current for use in the Premises
in excess of such reasonable quantity to be furnished as provided in Section 5.1
above and the Landlord, at its option, shall make such excess load available to
the Tenant, then the Tenant shall pay the Landlord's then standard charge for
such excess load availability along with the consumption charges specified in
Section 5.1. In addition to the foregoing charges, if, in the Landlord's
judgment, such additional electric current cannot be furnished unless additional
risers, conduits, feeders, switchboards and/or appurtenances are installed in
the Building, the Landlord, upon request of the Tenant, will proceed with
reasonable diligence to install such additional risers, conduits, feeders,
switchboards and/or appurtenances provided the same and the use thereof shall be
permitted by all laws, ordinances, rules, orders and regulations of all
governmental and quasi-governmental authorities and of all insurance bodies, at
any time duly issued and in force (collectively, "Requirements") applicable to
the Land, the Building or the Premises or any part thereof, to the Tenant's use
thereof or to the Tenant's observance of any provision of this Lease and shall
not cause damage or injury to the Building or the Premises or cause or create a
dangerous or hazardous condition or entail excessive or unreasonable alterations
or repairs or interfere with or disturb other tenants or occupants of the
Building, and the Tenant shall pay all reasonable costs and reasonable expenses
incurred by the Landlord in connection with such installation; provided, that
the Tenant may, at its expense, install such additional risers, feeders,
switchboards and/or appurtenances (and all work and actions in connection
therewith shall be subject to the provisions of subsection (e) of Article Six).
The Tenant shall purchase and install all lamps, starters and ballasts
(including replacements thereof) used in the lighting fixtures in the Premises.

      5.4. Hot and Cold water will be furnished by the Landlord at the
Landlord's cost and expense for normal use in cleaning and in lavatory, toilet
facilities, pantry and drinking fountains, if any, in the Premises. Where any
water is otherwise furnished or any steam is furnished by the Landlord
(exclusive of steam for heating the Premises), the Tenant shall pay (i) the cost
of supplying, installing and maintaining a meter to measure the water or steam
(exclusive of steam for heating the Premises) so furnished, (ii) the reasonable
charges of the Landlord for the water or steam (exclusive of steam for heating
the Premises) so furnished and, in the case of water, for any required pumping
and heating thereof, and (iii) any sales, use or similar taxes, sewer rent or
other charges which may be imposed by any government or agency thereof based
upon the quantity of water or steam so furnished or the charge therefor.

      5.5. The Landlord shall in no way be liable for any failure, inadequacy or
defect in the character or supply of electric current, water or steam furnished
to the Premises except for actual damage suffered by the Tenant by reason of any
such failure, inadequacy or defect caused by the gross negligence or willful
misconduct of the Landlord.

                                   ARTICLE SIX
                                Various Covenants

      6.1. The Tenant shall:

            (a) take good care of the Premises, keep clean the portions of the
      Premises which the Landlord is not required by this Lease to clean, and
      pay the cost of making good any injury, damage or breakage (including,
      without limitation, the cost of removing stains from floors and walls)
      done by the Tenant, any other occupant of the Premises (other than the
      Landlord), any affiliate thereof, or any of their respective employees,
      officers, directors, partners, contractors, agents, licensees or invitees
      (each, a "Tenant Party"), other than any damage with respect to which the
      Tenant is released from liability pursuant to Section 9.3;

            (b) observe and comply with the rules and regulations annexed to,
      and made a part of, this Lease and such other and further reasonable rules
      and regulations as the Landlord hereafter at any time may make and
      communicate to the Tenant and which, in the judgment of the Landlord
      reasonably exercised, shall be necessary or desirable for the reputation,
      safety, care or appearance of the Center, or the preservation of good
      order therein, or the operation or maintenance of the Center, or the
      equipment thereof, or the comfort of

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      tenants or others in the Center; provided, however, that in the case of
      any conflict between the provisions of this Lease and any such rule or
      regulation, the provisions of this Lease shall control;

            (c) permit the Landlord, any landlord under any of the underlying
      leases, any mortgagee under any of the underlying mortgages and any other
      party designated by the Landlord, and their respective representatives, to
      enter the Premises upon prior reasonable notice (which may be oral) at
      such hours as shall not unreasonably interfere with the Tenant's business,
      for the purposes of inspection and permit them or any of their agents or
      contractors to enter at any time without notice in case of emergency and
      otherwise at any time with reasonable notice for the purpose of complying
      with any Requirement or exercising any right reserved to the Landlord
      under Article Eight or elsewhere by this Lease in which case the Landlord
      shall act in a commercially reasonable manner (it being understood that
      the parties specified in this subsection are third-party beneficiaries of
      the covenants specified in this subsection in the event of the Landlord's
      breach of any obligation it may have to any such party to exercise a right
      of access on such party's behalf);

            (d) make no claim against the Landlord or any landlord under any of
      the underlying leases for any injury or damage to the Tenant or to any
      other person or for any damage to, or loss (by theft or otherwise) of, or
      loss of use of, any property of the Tenant or of any other person,
      irrespective of the cause of such injury, damage or loss, unless caused by
      the gross negligence or willful misconduct of the Landlord, its agents,
      servants or employees, in the operation or maintenance of the Premises or
      the Building, it being understood that no property other than such as
      might normally be brought upon or kept in the Premises as an incident to
      the reasonable use of the Premises for the purposes specified in this
      Lease will be brought upon or kept in the Premises;

            (e) make no alteration, change, addition, improvement, repair or
      replacement (an "Alteration") in, to, or about, the Premises, and do no
      work in such connection, without in each case the prior review and consent
      of the Landlord, and then only by workmen and contractors of the Landlord
      or by workmen and contractors of the Tenant acceptable to the Landlord,
      and in a manner in keeping with the landmark status of, and consistent
      with, the design, construction and equipment of the Building and the
      Center and upon terms and conditions and at times, reviewed and consented
      to by the Landlord and in accordance with the rules, regulations and
      guidelines of the Landlord pertaining to the performance of such
      Alterations, and make no contract for nor employ any labor in connection
      with the maintenance, cleaning or other servicing of the Premises (a
      "Tenant Service") without like consent, which consents, to the extent
      granting same shall not impose any additional burden on Landlord but only
      in the case of nonstructural Alterations and structural Alterations
      required by any Requirement applicable to the Premises or any part thereof
      or to Tenant's use thereof or to Tenant's observance of any provision of
      this Lease, shall not be unreasonably withheld; in addition, the Tenant
      shall:

                  (i) notwithstanding anything in this Lease to the contrary,
            make all changes (once reviewed and consented to by the Landlord),
            whether or not structural and whether or not in the Premises,
            required by any Requirement as a result of any Alteration or Tenant
            Service;

                  (ii) pay as and when the same become due and payable all
            reasonable charges incurred by it in connection with any Alteration
            including, but not limited to, the Landlord's reasonable charges for
            making such reviews and inspections as it may deem necessary or
            desirable in connection with the consideration of the granting of,
            and compliance with, any such consent;

                  (iii) if any notice or claim of any lien be given or filed by
            or against the Building or the Land for any work, labor or services
            performed, or for any materials, products or equipment used,
            furnished or manufactured for use, therein or thereon or in
            connection with the performance of any Alteration or Tenant Service,
            promptly, but in all events within thirty (30) days, discharge or
            remove the same by payment, bonding or otherwise; other than any
            lien given or filed in connection with any work, labor or service,
            or for any materials, products or equipment used, furnished or
            manufactured for use in connection with the installation of a
            sprinkler tap and loop by the Landlord pursuant to Article Thirty
            hereof;

<PAGE>   11
                                       8


                  (iv) notwithstanding any such review and consent, not permit
            the use of any contractors, workmen, labor, material or equipment in
            the performance of any Alteration or Tenant Service if the use
            thereof, in the Landlord's judgment reasonably exercised, will
            disturb harmony with any trade engaged in performing any other work,
            labor or service in or about the Building or the Center or
            contribute to any labor dispute;

                  (v) permit no such work to be undertaken in connection with
            any Alteration or Tenant Service unless insurance protecting the
            Tenant and each of the Tenant's consultants, contractors and
            subcontractors, and the Indemnitees (as hereinafter defined),
            against liability for worker's compensation and for bodily injuries
            and death, as well as for property damage arising out of or in
            connection with the performance and completion of such Alteration,
            shall be procured and maintained in full force and effect throughout
            the prosecution thereof, at the sole cost and expense of the Tenant
            and/or its consultants, contractors and subcontractors; all such
            insurance to be commercially reasonable as to form, amounts and
            insurers and reasonably acceptable to the Landlord and the Tenant
            will furnish to the Landlord certificates of such insurance prior to
            the commencement of such work; and

                  (vi) deliver, within thirty (30) days after completion of the
            Alteration, record drawings and specifications of the Premises
            reflecting the Alteration prepared on an Autocad Computer Assisted
            Drafting and Design ("CADD") System (or such other system or medium
            as the Landlord may accept) using naming conventions issued by the
            American Institute of Architects ("AIA") in June 1990 (or such other
            naming convention the Landlord may accept) and magnetic computer
            media of such record drawings and specifications, translated into
            DXF format or another format accepted by the Landlord;

            (f) not violate, or permit the violation of, any condition imposed
      by the standard fire insurance policy issued for office buildings in the
      Borough of Manhattan, New York, N.Y., and not do, suffer or permit
      anything to be done, or keep, suffer or permit anything to be kept, in the
      Premises, which would increase the fire or other casualty insurance rate
      on the Building or property therein, or which would result in insurance
      companies of good standing refusing to insure the Building or any such
      property in amounts and against risks as reasonably determined by the
      Landlord;

            (g) permit the Landlord to show the Premises at reasonable times
      upon prior reasonable notice (which may be oral) during Business Hours (as
      hereinafter defined) to any lessee, or any prospective purchaser, lessee,
      mortgagee or assignee of any mortgage or underlying lease, of the Building
      and/or the Land or of the Landlord's interest therein, and their
      representatives, and during the 12 months preceding the expiration of this
      Lease with respect to any part of the Premises similarly show such part to
      any person contemplating the leasing of all or a portion of the same;

            (h) at the expiration or any earlier termination of this Lease with
      respect to any part of the Premises, terminate its occupancy of, and quit
      and surrender to the Landlord, such part of the Premises broom-clean and
      in as good condition as it was at the commencement of such term, except
      for (1) ordinary wear and tear, (2) condemnation, (3) damage, not required
      to be repaired or replaced by the Tenant and (4) loss or damage by fire or
      other casualty, which shall not have been occasioned by the fault of any
      Tenant Party or with respect to which the Tenant is released from
      liability pursuant to Section 9.3;

            (i) at any time and from time to time upon not less than ten (10)
      days' prior notice by the Landlord, execute, acknowledge and deliver to
      the Landlord a statement of the Tenant (or if the Tenant is a corporation
      or a partnership, an appropriate officer or partner, as the case may be,
      of the Tenant) certifying that this Lease is unmodified and in full force
      and effect (or if there have been modifications, that the same is in full
      force and effect as modified and stating the modifications), and the dates
      to which the Rent has been paid in advance, if any, stating whether or not
      to the best knowledge of the signer of such certificate the Landlord is in
      default in the keeping, observance or performance of any provision
      contained in this Lease and, if so, specifying each such default, and such
      other information as Landlord may reasonably request, it being intended
      that any such statement may be relied upon by any landlord under any
      underlying lease (as defined

<PAGE>   12
                                       9


      in Article Thirteen hereof) or any lessee or mortgagee, or any prospective
      purchaser, lessee, mortgagee or assignee of any underlying mortgage (as
      defined in Article Thirteen hereof);

            (j) indemnify, and save harmless, the Landlord, and its agents and
      partners and its and their respective contractors licensees, invitees,
      servants, officers, directors, agents and employees, any mortgagee under
      any underlying mortgage and any landlord under any of the underlying
      leases (the "Indemnitees") from and against all liability (statutory or
      otherwise), claims, suits, demands, damages, judgments, costs, interest
      and expenses (including reasonable counsel fees and disbursements incurred
      in the defense thereof) to which any Indemnitee may (except insofar as it
      arises out of the gross negligence or willful misconduct of any such
      Indemnitee in the operation and maintenance of the Building) be subject or
      suffer whether by reason of, or by reason of any claim for, any injury to,
      or death of, any person or persons or damage to property (including any
      loss of use thereof) or otherwise arising from or in connection with the
      use of, or from any work or thing whatsoever done in, any part of the
      Premises (other than by such Indemnitee) or by any Tenant Party in the
      Center during the term of this Lease or during the period of time, if any,
      prior to the commencement of such term that the Tenant may have been given
      access to such part for the purpose of doing work or otherwise, or as a
      result of any Tenant Party performing any such work or otherwise that
      subjects any Indemnitee to any Requirement to which such Indemnitee would
      not otherwise be subject, or arising from any condition of the Premises
      due to or resulting from any default by the Tenant in the keeping,
      observance or performance of any provision contained in this Lease or from
      any act or negligence of any Tenant Party; and

            (k) maintain, at all times during the term of this Lease and during
      any other times the Tenant is granted access to the Premises, a policy or
      policies of commercial general liability insurance (including, without
      limitation, insurance of the Tenant's contractual liability under this
      Lease) written on an occurrence basis with the premiums fully paid on or
      before the due date, issued by a reputable insurance company licensed to
      do business in the State of New York, having a minimum rating A- by A.M.
      Best & Company or such other financial rating as the Landlord may at any
      time consider appropriate, and reasonably acceptable to the Landlord. Such
      insurance shall afford minimum limits as the Landlord may reasonably
      designate from time to time, but in no event less than $3,000,000 per
      occurrence with a $5,000,000 aggregate in respect of injury or death to
      any number of persons and not less than $3,000,000 for damage to or loss
      of use of property in any one occurrence. Each such policy shall provide
      that it cannot be cancelled except upon 30 days' prior notice to the
      Landlord and shall name the Indemnitees and such other designees as the
      Landlord may from time to time designate as additional insureds
      thereunder. The Tenant shall furnish original certificates of such
      insurance to the Landlord prior to the term commencement date (or any date
      on which the Tenant is granted earlier access) and thereafter not less
      than 30 days prior to the expiration of each such policy and any renewals
      or replacements thereof.

      6.2. The Landlord shall at any time and from time to time upon not less
than 10 days' prior notice by the Tenant, execute, acknowledge and deliver to
the Tenant a statement of the Landlord certifying that this Lease is unmodified
and in full force and effect (or if there have been modifications, that the same
is in full force and effect as modified and stating the modifications), and the
dates to which the fixed rent and additional rent have been paid in advance, if
any, and stating whether or not to the best knowledge of the signer of such
certificate the Tenant is in default in the keeping, observance or performance
of any term or condition contained in this Lease and, if so, specifying each
such default of which the signer may have knowledge, it being intended that any
such statement may be relied upon by any assignee, prospective assignee,
subtenant or prospective subtenant of the Tenant.

                                  ARTICLE SEVEN
                    Assignment, Mortgaging, Subletting, etc.

      7.1. Except as may be otherwise specifically provided in this Article, the
Tenant covenants, for the Tenant and its successors, assigns and legal
representatives, that neither this Lease nor the term and estate hereby granted,
nor any part hereof or thereof, will be assigned, mortgaged, pledged, encumbered
or otherwise transferred (it

<PAGE>   13
                                       10


being agreed that (y) issuance by the Tenant of stock and/or the transfer of
already-issued stock/partnership interest, in one or more transactions so as to
transfer control or transfer 50% or more of an interest in the Tenant, other
than through over-the-counter or national securities exchange transactions by
those holding less than a 5% interest in the Tenant, or (z) sale or transfer of
25% or more of the assets of the Tenant in one or more transactions, other than
in the ordinary course of business, shall, in either event, be deemed an
assignment of this Lease), and that neither the Premises, nor any part thereof,
will be encumbered in any manner by reason of any act or omission on the part of
the Tenant, or will be used or occupied, or permitted to be used or occupied, or
utilized for desk space, for mailing privileges or as a concession, by anyone
other than the Tenant, or will be sublet, or offered or advertised for
subletting; provided, however, that, if the Tenant is a corporation, (a) the
assignment or transfer of this Lease, and the term and estate hereby granted, to
any (1) corporation into which the Tenant is merged or with which the Tenant is
consolidated or (2) partnership to which all of the assets of the Tenant are
transferred and only for so long as the Tenant retains management control of
said partnership and is owner of more than fifty (50%) percent of the
partnership interests of said partnership (such corporation or partnership being
hereinafter in this Article called the "Assignee") without the prior consent of
the Landlord shall not be deemed to be prohibited hereby if, and upon the
express conditions that, (i) the primary purpose for such merger, consolidation
or partnership change is other than the transfer of this Lease, (ii) the
surviving entity has a net worth at least equal to that of the Tenant's on the
date hereof or the date of merger, consolidation or partnership change,
whichever is greater, and (iii) at least thirty (30) days prior to the merger,
consolidation or partnership change, the Assignee shall have executed and
delivered to the Landlord an agreement in form and substance satisfactory to the
Landlord whereby the Assignee shall agree to be personally bound by and upon all
the provisions set forth in this Lease on the part of the Tenant to be kept,
observed or performed, and whereby the Assignee shall expressly agree that the
provisions of this Article shall, notwithstanding such assignment or transfer,
continue to be binding upon it with respect to all future assignments and
transfers, (b) the Landlord will consent to the Tenant permitting the Premises
to be used and occupied for the purposes specified in, and subject to the
provisions of, this Lease, by any subsidiary or affiliate of the Tenant or
Tenant's parent, but only for so long as the occupant remains a subsidiary or
affiliate of the Tenant or Tenant's parent, provided that (I) the Tenant
provides reasonable evidence of the relationship of the subsidiary or affiliate
to the Tenant or Tenant's parent, (II) in the Landlord's reasonable judgment the
subsidiary or affiliate or Tenant's parent is of a character and engaged in a
business such as in keeping with the standards in those respects for the
Building and its occupancy and (III) it being understood that an entity shall
only be a subsidiary of the Tenant or Tenant's parent if the Tenant or Tenant's
parent owns, directly or indirectly, 50% or more of the stock or partnership
interests in the entity and shall only be an affiliate of the Tenant or Tenant's
parent if under common ownership, that is, direct or indirect ownership by an
entity holding 50% or more of the stock or partnership interests in both the
Tenant or Tenant's parent and such affiliate and (c) the Landlord will consent
to the Tenant permitting the Premises to be used and occupied for the purposes
specified in, and subject to the provisions of, this Lease, by any corporation
or partnership in which, and only for so long as, Elizabeth Lavin remains the
owner, directly or indirectly, of 100% of the stock or partnership interest of
such entity, provided that (I) the Tenant provides reasonable evidence of the
relationship of such entity to Elizabeth Lavin, and (II) in the Landlord's
reasonable judgment the entity is of a character and engaged in a business such
as in keeping with the standards in those respects for the Building and its
occupancy.

      7.2.1. In the event the Tenant desires the Landlord's consent to the
subletting of all or any part of the Premises for any part of the term of this
Lease with respect thereto, the Tenant shall notify the Landlord of the name of
the proposed sublessee, such information as to the proposed sublessee's
business, financial responsibility and standing as the Landlord may reasonably
require, and of the terms and conditions of the proposed subletting, which
notice shall (except in the case of (x) a proposed subletting to a subsidiary of
the Tenant or, (y) proposed sublettings commencing in the first three years of
the term of this Lease for space or spaces, individually or in the aggregate,
totaling 30% or less of the rentable square foot area of the Premises) contain
an offer to vacate and surrender, as of the Special Surrender Date (as
hereinafter defined), either (i) if the Tenant proposes to sublet only a part of
the Premises, the space to be demised by the proposed sublease, together with
such other space, if any, as is demised to the Tenant by this Lease as may be
reasonably required for public corridors, toilets and core facilities serving
the space so proposed to be sublet (said spaces(s) being herein collectively
called a "Partial Space"), or (ii) if the Tenant proposes to sublet the entire
Premises, the entire Premises. The term "Special Surrender Date" as used in this
Article, shall mean a date to be specified in such notice from the Tenant;
provided, however, said specified date shall be (a) the last day of a calendar
month during the term hereof with

<PAGE>   14
                                       11


respect thereto, and (b) not earlier than a date occurring sixty (60) days after
the giving of such notice and not later than the date for the commencement of
the term of the proposed subletting.

      7.2.2. The Landlord may accept such offer by a notice given to the Tenant
within thirty (30) days after the receipt of such notice from the Tenant. If the
Landlord accepts such offer and such offer pertains to a Partial Space, then
effective as of the Special Surrender Date, this Lease shall be deemed modified
so that the term and estate granted by this Lease with respect to such Partial
Space (unless the same shall have expired sooner pursuant to any of the other
conditions of limitation or provisions of this Lease or pursuant to law) shall
expire on the Special Surrender Date with the same effect as if the Special
Surrender Date were the date specified in this Lease for the expiration of the
term of this Lease with respect to such Partial Space and the annual fixed rent
payable hereunder, to the extent that such fixed rent relates to such Partial
Space and such abatement is in excess of the annual rate of any other existing
abatement of fixed rent relating thereto under any other term or condition of
this Lease, shall be abated at the Applicable Rental Rate (as hereinafter
defined) for each square foot of the rentable area of the Partial Space from and
after the Special Surrender Date. If the Landlord accepts such offer and such
offer pertains to the entire Premises, then this Lease shall be deemed modified
so that the term and estate granted by this Lease (unless the same shall have
expired sooner pursuant to any of the conditions of limitation or other
provisions of this Lease or pursuant to law) shall expire on the Special
Surrender Date with the same effect as if the Special Surrender Date were the
date specified in this Lease for the expiration of the term hereof and the fixed
rent payable hereunder shall be apportioned as of the Special Surrender Date.
The Tenant shall terminate its occupancy of such Partial Space or the Premises,
as the case may be, not later than the Special Surrender Date.

      7.2.3. The term "Applicable Rental Rate" as used in this Article shall be
deemed to mean $31.00 per annum for the period commencing on the term
commencement date and ending on September 30, 1999; and $35.00 per annum
thereafter.

      7.2.4. In the event of such expiration of the term of this Lease with
respect to a Partial Space, any changes, improvements and alterations to any
portion of the remaining Premises demised by this Lease after the Special
Surrender Date (including, but not limited to, the erection of a boundary wall
to separate such portion from such Partial Space) made necessary or desirable in
the Landlord's reasonable judgment by reason of such expiration shall be made by
the Landlord at the Tenant's expense.

      7.2.5. In the event the Landlord does not accept an offer made by the
Tenant in a notice given to the Landlord pursuant to Section 7.2.1. hereof or
the Tenant is not required to make such an offer in such notice, the Landlord
will not unreasonably withhold or delay its consent to the proposed subletting
referred to in said notice on the terms and conditions set forth in said notice;
provided, however, that the Landlord shall not in any event be obligated to
consent to any such proposed subletting unless:

                  (a) the sublessee under any such subletting shall be such
            person, firm or corporation as in the Landlord's reasonable judgment
            is of a character and engaged in a business such as is in keeping
            with the standards in those respects for the Building and its
            occupancy and shall not be a (i) government or a governmental
            authority or a subdivision or an agency of any government or any
            governmental authority or (ii) a tenant of either the Landlord or a
            subsidiary or affiliate of the Landlord, provided that the Landlord
            has comparable space available in the Center for such tenant;

                  (b) such subletting shall be at a rental rate not less than
            ninety percent (90%) of the rental rates then being charged under
            leases being entered into by the Landlord for comparable space in
            the Center and for a comparable term and provided that the Tenant
            shall not advertise such rates in any publicly disseminated medium;

                  (c) the space so to be sublet shall be regular in shape;

                  (d) such consent shall be evidenced by the delivery of, and
            shall be subject to the terms and conditions of, a "Consent to
            Sublease" duly executed by the Landlord, the Tenant and the
            sublessee which Consent to Sublease shall be substantially in the
            form attached as Exhibit C and on such customary form of the
            Landlord as is adopted by it for such purpose, for which the

<PAGE>   15
                                       12


            Tenant shall pay to the Landlord a reasonable processing charge in
            connection therewith, which charge shall not exceed $3,000.00; and

                  (e) the Tenant and the sublessee shall agree that the
            sublessee will not, without the prior consent of the Landlord,
            assign the sublease or under-sublet the space so sublet or any part
            thereof.

      7.2.6. All of the terms and conditions of any such "Consent to Sublease"
so executed by the Landlord, the Tenant and the sublessee shall be deemed to be
terms and conditions of this Lease and the violation by the Tenant or the
sublessee of any term or condition of such "Consent to Sublease" shall entitle
the Landlord to all the rights and remedies provided for in this Lease or by law
in the case of any violation of a term or condition of this Lease.

      7.2.7. If the aggregate amount payable as rent (including without
limitation, all amounts payable on account of changes in Real Estate Taxes,
operating costs, maintenance costs, labor rates, indexes or other formula
contained in the sublease) with respect to any period of time by a sublessee
under a sublease of any part of the Premises made by the Tenant shall be in
excess of the Tenant's Basic Cost (as hereinafter defined) for such period for
such part of the Premises, then, promptly after the collection by the Tenant of
such amounts so payable for such period under such sublease, the Tenant will pay
to the Landlord, as additional rent hereunder, an amount equal to 50% of the
excess of such amounts so collected for such part of the Premises over the
Tenant's Basic Cost for such part of the Premises for such part of the term. The
term "Tenant's Basic Cost," as used herein with respect to any period for which
any part of the Premises is sublet, shall mean the sum of (i) fixed rent at the
Applicable Rental Rate for each square foot of the rentable area of such part of
the Premises, and (ii) the amount payable by the Tenant to the Landlord for such
period with respect to such part of the Premises pursuant to Article Twenty-four
hereof. The Tenant shall diligently enforce all rights it has under any sublease
and at law to collect all amounts payable by the sublessee.

      7.2.8. The Tenant shall deliver to the Landlord a statement within thirty
(30) days after the end of each calendar year in which any part of the term of
this Lease occurs specifying as to such calendar year, and within thirty (30)
days after the expiration or earlier termination the term of this Lease
specifying with respect to the elapsed portion of the calendar year in which
such expiration or termination occurs (a) each sublease in effect during the
period covered by such statement and as to each sublease, the date of its
execution and delivery, the number of square feet of the rentable area demised
thereby, the term thereof, and a computation in reasonable detail showing
whether or not anything is payable by the Tenant to the Landlord pursuant to
this Article with respect to such sublease for the period covered by such
statement; and (b) whether or not anything is payable by the Tenant to the
Landlord pursuant to this Article with respect to any payments received from a
sublessee during such period but which relate to an earlier period and showing
in reasonable detail the computation of the amount so payable.

      7.2.9. Each sublease of the Premises or a portion thereof shall be subject
and subordinate to this Lease and the rights of the Landlord under this Lease
and any violation of any provision of this Lease, whether by act or omission, by
any sublessee shall be deemed a violation of such provision by the Tenant, it
being the intention of the parties that the Tenant shall assume and be liable to
the Landlord for any and all acts and omissions of all sublessees if such act or
omission, if made by the Tenant, would be a violation of any provision of this
Lease. No sublease shall provide for a term which extends beyond the day prior
to the then expiration date of this Lease. In the event of the Tenant's default
in the payment of any fixed rent and/or additional rent under this Lease beyond
any applicable period of grace, the Landlord may collect rent from any sublessee
so long as such default shall continue, and the Landlord may apply the same to
the curing of any such default under this Lease in any order of priority the
Landlord may select, any unapplied balance thereof to be applied by the Landlord
against subsequent installments of Rent, but the Landlord's collection of Rent
from a sublessee shall not constitute a recognition by the Landlord of
attornment by such sublessee nor a waiver by the Landlord of any default by the
Tenant.

      7.2.10. As security for the performance of the Tenant's obligations under
this Lease, the Tenant hereby agrees that if and only for so long as the Tenant
shall be in default in the payment of fixed rent and/or additional rent payable
under this Lease beyond any applicable period of grace, the Tenant shall assign
(and, subject to the

<PAGE>   16
                                       13


conditions set forth herein, hereby does assign) to the Landlord all of the
Tenant's interest in and to all present and future subleases of space in the
Premises, together with all modifications, renewals and extensions thereof now
existing or hereafter made, and also together with the rights to sue for,
collect and receive all rents, additional rents and other sums payable to the
Tenant under such subleases.

      7.3. Without in any way suggesting permission for the Tenant to assign the
Lease, if the Lease is nonetheless assigned by the order of a court or otherwise
but not as permitted by Section 7.1 above, the Tenant shall pay to the Landlord
75% of any consideration received by the Tenant for the assignment, net of
brokerage commissions and legal fees incurred by the Tenant in connection
therewith and not reimbursed by the assignee. The amounts to be paid to the
Landlord under this Section shall be deemed to be deferred rent payable only out
of amounts collected by the Tenant in connection with an assignment and shall be
deemed forgiven if no assignment occurs.

      7.4. The Landlord will, at the request of the Tenant, maintain listings on
the Building directory of the names of the Tenant and the names of any officers
or employees of the Tenant; provided, however, that the number of names so
listed shall be in the same proportion to the capacity of the building directory
as the aggregate number of square feet of rentable area of the Premises is to
the aggregate number of square feet of rentable area of the Center. Without
implying any right to do so, the listing of any name other than that of the
Tenant, whether on the doors or windows of the Premises, on the Building
directory, or otherwise, shall not operate to vest any right or interest in this
Lease or in the Premises or be deemed to be the consent of the Landlord referred
to in Section 7.1, it being expressly understood that any such listing is a
privilege extended by the Landlord revocable at will by notice to the Tenant.

                                  ARTICLE EIGHT
                       Changes or Alterations by Landlord

      8.1.1. The Landlord reserves the right to make such Alterations in or to
the Building (including the Premises) and the fixtures and equipment thereof, as
well as in or to the street entrances, halls, passages, elevators, escalators
and stairways and other parts of the Building and the Center, and to erect,
maintain and use pipes, ducts and conduits in and through the Premises, all as
it may reasonably deem necessary or desirable; provided, that (a) the exercise
of such rights shall not result in an unreasonable obstruction of the means of
access to the Premises or unreasonable interference with the use of the
Premises, (b) that the Landlord will restore the portion of the Premises
affected by any such Alterations to its condition existing prior to the
commencement of the work in connection therewith to the extent reasonably
practicable in light of the Alterations made, and/or (c) if any such Alterations
shall reduce the floor area of the Premises (other than a de minimus amount),
the fixed rent payable hereunder (to the extent that such fixed rent relates to
such part of the floor area of the Premises and such abatement is in excess of
the annual rate of any other existing abatement of fixed rent relating to such
part of the floor area of the Premises under any other term or condition of this
Lease) shall be abated with respect to such part of the floor area of the
Premises for the period from the date of the making thereof to the date
specified in this Lease for the expiration of the full term of this Lease.
Nothing in this Section or in Article Six shall be deemed to relieve the Tenant
of any duty, obligation or liability to make any repair, replacement or
improvement or comply with any Requirement.

      8.1.2. The Landlord will, subject to, and except as otherwise provided in,
the other terms and conditions of this Lease, with reasonable dispatch and in a
manner and at such times as shall not unreasonably interfere with the use of the
Premises nor unreasonably obstruct the means of access to the Premises, make as
and when required all repair, structural or otherwise, interior or exterior, to
the Building to the extent the failure to do so would adversely affect the
Tenant's use of or access to the Premises (including its public areas, fixtures,
appurtenances, systems and facilities, but excluding anything which constitutes
subdivision, layout and finish of spaces in the Building rented to, or available
for renting to, tenants) as may be necessary to restore the same to a state of
good working order, condition and repair and to a standard in keeping with the
reputation of the Building as a location for an outstanding type of business
occupancy.

<PAGE>   17
                                       14


      8.2. The Landlord reserves the right to change the name or address of the
Building at any time. Neither this Lease nor any use by the Tenant shall give
the Tenant any right or easement to the use of any door or any passage
connecting the Building with any subway or any other building or to the use of
any public conveniences, and the use of such doors, passages and conveniences
may be regulated or discontinued at any time by the Landlord.

                                  ARTICLE NINE
                              Damage by Fire, etc.

      9.1. If any part of the Premises shall be damaged by fire or other perils,
the Tenant shall give prompt notice thereof to the Landlord and the Landlord
shall proceed with reasonable diligence subject to adjustment and collection of
any insurance proceeds and the provisions of any Qualified Encumbrance to repair
such damage, and, if any part of the Premises shall be rendered untenantable by
reason of such damage (including untenantability due to lack of access thereto),
the annual fixed rent payable under this Lease, to the extent that such fixed
rent relates to such part of the Premises, shall be abated for the period from
the date of such damage to the date when such part of the Premises shall have
been made tenantable or to such earlier date upon which either such part of the
Premises would have been tenantable but for Tenant Delay or the full term of
this Lease with respect to such part of the Premises shall expire or terminate,
unless (a) the Landlord shall make available to the Tenant, during the period of
such repair, other space in the Center, comparable in size and characteristics
to the Premises, reasonably suitable for the temporary carrying on of the
Tenant's business, or (b) such fire or other damage shall have resulted from the
negligence of any Tenant Party; provided that such abatement shall be made only
to the extent that it is in excess of the annual rate of any other existing
abatement of fixed rent relating thereto under any provision of this Lease other
than Section 1.4. hereof. The Landlord shall not be liable for any inconvenience
or annoyance to the Tenant or injury to the business of the Tenant resulting in
any way from such damage or the repair thereof The Tenant understands that the
Landlord will not carry insurance of any kind on (w) the Tenant's goods,
furniture or furnishings, (x) on any Fixtures removable by the Tenant as
provided in this Lease, (y) on Tenant improvements or betterments or (a) on any
property in the care, custody and control of the Tenant, and that the Landlord
shall not be obligated to repair any damage thereto or replace the same.

      9.2. If substantial alteration or reconstruction of the Building shall, in
the reasonable opinion of the Landlord, be required as a result of damage by
fire or other perils (whether or not the Premises shall have been damaged by
such fire or other casualty), then this Lease and the term and estate hereby
granted may be terminated by the Landlord by a notice, given within sixty (60)
days of such damage specifying a date, not less than thirty (30) days after the
giving of such notice, for such termination. In addition, if a substantial part
of the Premises is rendered untenantable as a result of such damage by fire or
other peril and it is determined by the Landlord that such part of the Premises
cannot be made tenantable within a period of fifteen (15) months after the
occurrence of such fire or other peril, then this Lease and the term and estate
hereby granted may be terminated by the Landlord or the Tenant by a notice
specifying a date, not less than thirty (30) days after the giving of such
notice for such termination, which notice must be given within sixty (60) days
(i) of such damage if such termination notice is given by the Landlord, or (ii)
the Tenant's receipt of the Landlord's estimate of the time needed to repair the
Premises if such termination notice is given by the Tenant. In the event of the
giving of notice of termination, this Lease and the term and estate hereby
granted shall expire as of the date specified in such notice with the same
effect as if such date were the date initially specified in this Lease as the
expiration date, and the fixed rent payable under this Lease shall be
apportioned as of such date of termination, subject to abatement, if any, as and
to the extent above provided.

      9.3. The Landlord and the Tenant hereby release each other with respect to
any liability which the released party might otherwise have to the releasing
party for any damage to the Building or the Premises or the contents thereof by
fire or other peril occurring during the term of this Lease to the extent of the
proceeds received under a policy or policies of insurance permitting such
release. Each party will use best efforts to cause its property and/or other
applicable insurance policy to include a provision permitting such a release of
liability; provided, that if such a provision is obtainable from such insurer
only at an additional expense, the insured party shall notify the other party
and, unless the other party pays such additional expense within ten (10) days
thereafter, the

<PAGE>   18
                                       15


insured party shall thereafter be free of its waiver of subrogation so long as
an additional cost is required under the policy in question.

      9.4. This Lease shall be considered an express agreement governing any
case of damage to or destruction of, or any part of, the Building or the
Premises by fire or other peril, and Section 227 of the Real Property Law of the
State of New York providing for such a contingency in the absence of express
agreement, and any other law of like import now or hereafter in force, shall
have no application in such case.

                                   ARTICLE TEN
                                  Condemnation

      10.1. If all of the Premises shall be lawfully condemned or taken in any
manner for any public or quasi-public use, this Lease and the term and estate
hereby granted shall forthwith cease and terminate as of the date of vesting of
title in such condemnation or taking. If only a part of the Premises shall be so
condemned or taken, then the term and estate hereby granted with respect to such
part of the Premises shall forthwith cease and terminate as of the date of
vesting of title in such condemnation or taking and the annual fixed rent
payable under this Lease, to the extent that such fixed rent relates to such
part of the Premises, shall be abated for the period from the date of such
vesting of title to the date specified in this Lease for the expiration of the
full term of this Lease with respect to such part of the Premises, but only to
the extent that such abatement is in excess of the annual rate of any other
existing abatement of fixed rent relating thereto under any other provision of
this Lease other than Section 1.4. hereof. If only a part of the Building shall
be so condemned or taken, then (a) if substantial alteration or reconstruction
of the Building or the Premises shall, in the reasonable opinion of the
Landlord, be necessary or desirable as a result of such condemnation or taking,
this Lease and the term and estate hereby granted may be terminated by the
Landlord within sixty (60) days following the date on which the Landlord shall
have received notice of such vesting of title, by a notice to the Tenant
specifying a date, not less than thirty (30) days after the Landlord's notice,
for such termination, or (b) if such condemnation or taking shall be of a
substantial part of the Premises or of a substantial part of the means of access
thereto, this Lease and the term and estate hereby granted may be terminated by
the Tenant, within sixty (60) days following the date upon which the Tenant
shall have received notice of such vesting of title, by a notice to the Landlord
specifying a date, not less than thirty (30) days after the Tenant's notice, for
such termination, or (c) if neither the Landlord nor the Tenant elects to
terminate this Lease, this Lease shall not be affected by such condemnation or
taking, except that this Lease and the term and estate hereby granted with
respect to the part of the Premises so condemned or taken shall expire on the
date of the vesting of title to such part and except that the fixed rent payable
under this Lease shall be abated to the extent, if any, hereinabove provided in
this Article. If only a part of the Premises shall be so condemned or taken and
this Lease and the term and estate hereby granted with respect to the remaining
portion of the Premises are not terminated, the Landlord will proceed with
reasonable diligence, subject to the provisions of any Qualified Encumbrance and
without requiring the Landlord to expend more than it collects as an award
therefor, to restore the remaining portion of the Premises as nearly as
practicable to the same condition as it was in prior to such condemnation or
taking.

      10.2. The termination of this Lease and the term and estate hereby granted
in any of the cases specified in this Article shall be with the same effect as
if the date of such termination were the date originally specified for the
expiration of the full term of this Lease, and the fixed rent payable under this
Lease shall be apportioned as of such date of termination.

      10.3. If there is any condemnation or taking of all or a part of the
Building, the Landlord shall be entitled to receive the entire award in the
condemnation proceeding, including any award made for the value of the estate
vested by this Lease in the Tenant, and the Tenant hereby expressly assigns to
the Landlord any and all right, title and interest of the Tenant now or
hereafter arising in or to any such award or any part thereof, and the Tenant
shall be entitled to receive no part of such award; provided, that the Tenant
shall not be precluded from intervening for the Tenant's own interest in any
such condemnation proceeding to claim or receive from the condemning authority
any compensation to which the Tenant may otherwise lawfully be entitled in such
case in

<PAGE>   19
                                       16


respect of property removable by the Tenant under Article Four or for moving
expenses, but only to the extent such compensation does not reduce the award
otherwise payable to the Landlord.

      10.4. If the whole or any part of the Premises, or of the Tenant's
leasehold estate, shall be taken in condemnation proceedings or by any right of
eminent domain for temporary use or occupancy, the foregoing provisions of this
Article Ten shall not apply and the Tenant shall continue to pay, in the manner
and at the times herein specified, the full amount of the rent and other charges
payable by the Tenant under this Lease, and, except only to the extent that the
Tenant may be prevented from so doing pursuant to the terms of the order of the
condemning authority, the Tenant shall perform and observe all of the other
provisions of this Lease upon the part of the Tenant to be performed and
observed, as though such taking had not occurred. In the event of any taking
referred to in this Section 10.4, the Landlord shall be entitled to receive any
portion of the condemnation proceeds paid as compensation for the cost of
restoration of the Building and the Tenant shall be entitled to receive the
balance of the condemnation proceeds paid for such taking, whether paid by way
of damages, rent or otherwise, unless such period of temporary use or occupancy
shall extend beyond the expiration or termination of this Lease, in which case
the balance of the condemnation proceeds shall be apportioned between the
Landlord and the Tenant as of the date of the expiration or termination of this
Lease. The Landlord shall, upon the expiration of any such period of temporary
use or occupancy, restore the Building, as nearly as may be reasonably possible
within the balance of the term of the Lease, to the condition in which the same
was immediately prior to such taking, subject to the provisions of any Qualified
Encumbrance and without requiring the Landlord to expend more than it collects
as an award therefor.

                                 ARTICLE ELEVEN
                              Compliance with Laws

      11.1. The Tenant shall comply with all Requirements applicable to the
Premises or any part thereof, to the Tenant's use thereof or to the Tenant's
observance of any provision of this Lease, except that the Tenant shall not be
under any obligation to comply with any Requirement requiring any structural
alteration of or in connection with the Premises solely by reason of the use
thereof for any of the purposes permitted in Article One and not by reason of
(i) a condition which has been created by, or at the instance of, any Tenant
Party, (ii) a breach by any Tenant Party of any provision of this Lease or (iii)
a Requirement having as a primary purpose the benefit of disabled persons. Where
any structural alteration of or in connection with the Premises is required by
any such Requirement, and, by reason of the express exception specified above,
the Tenant is not under any obligation to make such alteration, the Landlord
will make such alteration if the cost of making the same is not in excess of
fifty (50%) percent of the annual rate of fixed rent then payable under this
Lease (such cost shall not be deemed to include the cost of providing and
installing a sprinkler loop and tap, if such work is part of such alteration),
or if such cost is in excess of fifty (50%) percent of the annual rate of fixed
rent payable under this Lease then the Landlord shall have the option of making
such alteration or of terminating this Lease and the term and estate hereby
granted by giving to the Tenant not less than thirty (30) days' prior notice of
such termination; provided, that, if within fifteen (15) days after the giving
of notice of termination, the Tenant shall request the Landlord to make such
alteration at the expense of the Tenant, then such notice of termination shall
be ineffective; the Landlord shall proceed with reasonable diligence to make
such alteration and the Tenant shall pay to the Landlord all costs and expenses
incurred by the Landlord in connection therewith in excess of fifty (50%)
percent of the annual rate of fixed rent then payable under this Lease and shall
maintain on deposit with the Landlord such security for the payment of such
costs and expenses as the Landlord shall from time to time request. For purpose
of this Article, providing and installing of sprinklers shall be deemed to be a
non-structural alteration; except that the sprinkler loop and tap shall be
deemed a structural alteration.

      11.2. If a notice of termination shall be given by the Landlord under this
Article and such notice shall not become ineffective as above provided, this
Lease and the term and estate hereby granted shall terminate on the date
specified in such notice with the same effect as if such date were the date
originally specified for the expiration of this Lease, and the fixed rent
payable under this Lease shall be apportioned as of such date of termination.

<PAGE>   20
                                       17


                                 ARTICLE TWELVE
                     Accidents to Sanitary and other Systems

      12.1. The Tenant shall give to the Landlord prompt notice of any damage
to, or defective condition in, any part or appurtenance of the Building's
sanitary, electrical, heating, air conditioning, ventilating or other systems
serving, located in, or passing through, the Premises. Any such damage or
defective condition shall he remedied by the Landlord with reasonable diligence
except to the extent Tenant is specifically required to remedy same under the
terms of this Lease, but if such damage or defective condition (other than any
damage with respect to which the Tenant is relieved from liability pursuant to
Section 9.3) was caused by, or by the use by, any Tenant Party or is with
respect to any Fixture, installed by or at the request of Tenant or in
connection with the initial build-out of the Premises, the cost of the remedy
thereof shall be paid by the Tenant upon demand. The Tenant shall not be
entitled to claim any damages against the Landlord arising from any such damage
or defective condition unless the same shall have been caused by the gross
negligence or willful misconduct of the Landlord in the operation or maintenance
of the Premises or the Building and the same shall not have been remedied by the
Landlord with reasonable diligence after notice from the Tenant; nor shall the
Tenant be entitled to claim any damages against any other party (including,
without limitation, any third party vendor or other supplier of services to the
Landlord) arising from any such damage or defective condition unless the same
shall have been caused by the gross negligence or willful misconduct of such
party in the operation or maintenance of the Premises or the Building and the
same shall not have been remedied by such party with reasonable diligence after
notice thereof; nor shall the Tenant be entitled to claim any eviction by reason
of any such damage or defective condition unless the same shall have been caused
by the gross negligence or willful misconduct of the Landlord in the operation
or maintenance of the Premises or the Building and shall not have been made
tenantable by the Landlord within a reasonable time after notice from the
Tenant.

                                ARTICLE THIRTEEN
                                  Subordination

      13.1. This Lease and the term and estate hereby granted are and shall be
subject and subordinate to the lien of each mortgage which may now or at any
time hereafter affect the Premises, the Building and/or the Land, or the
Landlord's interest therein (collectively, the "underlying mortgages");
provided, however, that, the foregoing subordination to the lien of each
underlying mortgage, held by an affiliate, parent or subsidiary of the Landlord
only, shall be conditioned upon the Tenant's receipt from such mortgagee
thereunder of a subordination, nondisturbance and attornment agreement in form
and substance acceptable to such mortgagee and otherwise consistent with the
provisions of this Section 13.1. An entity shall only be a subsidiary of the
Landlord or Landlord's parent if the Landlord or Landlord's parent owns,
directly or indirectly, 50% or more of the stock or partnership interests in the
entity and shall only be an affiliate of the Landlord or the Landlord's parent
if under common ownership, that is, direct or indirect ownership by an entity
holding 50% or more of the stock or partnership interest in both the Tenant or
the Tenant's parent and such affiliate. If the Land is leased by the Landlord
from RCP Associates, a partnership, as successor in interest to The Trustees of
Columbia University in the City of New York pursuant to a lease dated October 1,
1928, as heretofore amended, this Lease and the term and estate hereby granted
are and shall be subject and subordinate to said lease as so amended and to each
agreement hereafter made modifying, supplementing, extending or renewing said
lease. If any part of the Premises is situated in the building known as 600
Fifth Avenue, this Lease and the term and estate hereby granted are and shall be
subject and subordinate to the lease dated August 23, 1949 from The Minister,
Elders and Deacons of The Reformed Protestant Dutch Church of the City of New
York to Massachusetts Mutual Life Insurance Company and to the lease dated June
16, 1949 from the Landlord to said Massachusetts Mutual Life Insurance Company
as each of said leases has been heretofore amended (the Landlord being the
successor in interest to said Massachusetts Mutual Life Insurance Company under
each of said leases) and to each agreement hereafter made modifying,
supplementing, extending or renewing either of said leases. If any part of the
Premises is situated in the building known as 75 Rockefeller Plaza, this Lease
and the term and estate hereby granted are and shall be subject and subordinate
to the lease dated October 18, 1977 from 75 Plaza Limited, N.V. to the Landlord,
as heretofore amended, and to each agreement hereafter made modifying,
supplementing, extending or

<PAGE>   21
                                       18


renewing said lease. This lease shall also be subject and subordinate to any
future ground or net lease of the Land and/or the Building; provided, however,
that, the foregoing subordination to the lien of any ground or net lease of the
Land and/or the Building, held by an affiliate, parent or subsidiary of the
Landlord only, shall be conditioned upon the Tenant's receipt from such lessor
thereunder of a subordination, nondisturbance and attornment agreement in form
and substance acceptable to such lessor and otherwise consistent with the
provisions of this Section 13.1. All of said leases as so modified,
supplemented, extended and renewed are herein collectively called the
"underlying leases". If any part of the Premises is situated in the building
known as 30 Rockefeller Plaza and 1250 Avenue of the Americas, this Lease and
the term and estate hereby granted are and shall be subject and subordinate to
the Declaration Establishing a Plan for Condominium Ownership of The Rockefeller
Center Tower Condominium (and the by-laws annexed thereto) dated as of December
1, 1988, as the same may have been or may hereafter be amended. The foregoing
provisions for the subordination of this Lease and the term and the estate
hereby granted shall be self-operative and no further instrument shall be
required to effect any such subordination; but the Tenant shall, from time to
time, upon request by the Landlord, execute and deliver any and all instruments
that may be necessary or proper to effect such subordination or to confirm or
evidence the same, and in the event that the Tenant shall fail to execute and
deliver any such instrument, the Landlord, in addition to any other remedies,
may, as the agent or attorney-in-fact of the Tenant, execute and deliver the
same, and the Tenant hereby irrevocably constitutes and appoints the Landlord
the Tenant's agent and attorney-in-fact, coupled with an interest, for such
purpose. If the Landlord's interest in the Building or the Land shall be sold or
conveyed to any person, firm or corporation upon the exercise of any remedy
provided for in any underlying mortgage or by law or equity, or if the
Landlord's interest in this Lease is assigned or conveyed to the landlord under
any ground lease as a result of a default by the tenant under the ground lease
and a resulting termination thereof, such person, firm or corporation succeeding
to the Landlord's interest in the Building or Land or this Lease and each
person, firm or corporation thereafter succeeding to its interest in the
Building or the Land or this Lease (i) shall not be liable for any act or
omission of the Landlord under this Lease occurring prior to such sale or
conveyance, (ii) shall not be subject to any offset, defense or counterclaim
accruing prior to such sale or conveyance, (iii) shall not be bound by any
payment prior to such sale or conveyance of Rent for more than one month in
advance (except prepayments in the nature of security for the performance by the
Tenant of its obligations hereunder), (iv) shall not be bound by any amendment
or modification of this Lease made (y) after notice to the Tenant of the
execution of the underlying mortgage or underlying lease in question and (z)
without the consent of such mortgagee or lessor (or their nominees, successors
or assigns), where required, (v) shall not be bound by any covenant to perform
(including, without limitation, any covenant to complete) any renovation or
construction in connection with the Premises or the Building or to pay any sums
to the Tenant in connection therewith, in either case arising or accruing prior
to the date of such sale or conveyance of the Landlord's interest; and (vi)
shall be liable for the performance of the other obligations of the Landlord
under this Lease only during the period such successor landlord shall hold such
interest. Within thirty (30) days following execution and delivery of this
Lease, the Landlord shall deliver to the Tenant for its signature a
subordination, nondisturbance and attornment agreement among the Landlord, the
Tenant and Rockefeller Center Properties, Inc., in form and substance acceptable
to Rockefeller Center Properties, Inc. and otherwise consistent with the
provisions of this Section 13.1. Except as otherwise expressly provided herein,
the Landlord agrees to use reasonable efforts to obtain a subordination,
nondisturbance and attornment agreement from the future holders of any
underlying mortgages in form and substance acceptable to such future holders of
such underlying mortgages and otherwise consistent with the provisions of
Section 13.1.

      13.2. If this Lease and the term and estate hereby granted are subject and
subordinate to any underlying lease, then the Tenant hereby agrees (a) that it
will attorn to the lessor under said underlying lease effective as of the
expiration or earlier termination of the term of said underlying lease and will
recognize said lessor as the Landlord under this Lease, and (b) that,
notwithstanding such expiration or earlier termination of the term of said
underlying lease, this Lease shall continue for the balance of the term of this
Lease in accordance with its provisions. Within thirty (30) days following
execution and delivery of this Lease, the Landlord shall deliver to the Tenant
for its signature a subordination, nondisturbance and attornment agreement
between the Tenant and RCP Associates, in form and substance acceptable to RCP
Associates and otherwise consistent with the provisions of Section 13.1. Except
as otherwise expressly provided herein, the Landlord agrees to use reasonable
efforts to obtain a subordination, nondisturbance and attornment agreement from
the future holders of any underlying leases

<PAGE>   22
                                       19


in form and substance acceptable to such future holders of such underlying
leases and otherwise consistent with the provisions of Section 13.1.

                                ARTICLE FOURTEEN
                                    Notices

      14.1. Any notice, consent, approval, request, communication, bill, demand
or statement (collectively, "Notices") under this Lease by either party to the
other party shall be in writing and shall be deemed to have been duly given when
delivered personally or by overnight mail service to such other party and a
receipt has been obtained or on the third day after being mailed in a postpaid
envelope (registered or certified, return receipt requested) addressed to such
other party, which address for the Landlord shall be as above set forth and for
the Tenant shall be the Premises to the attention of John A. Levin (or the
Tenant's address as above set forth if mailed prior to the Term Commencement
Date), or if the address of such other party for notices shall have been duly
changed as hereinafter provided, if so mailed to such other party at such
changed address. Either party may at any time change the address for Notices by
a Notice stating the change and setting forth the changed address. If the term
"Tenant" as used in this Lease refers to more than one person, any Notice to any
one of such persons shall be deemed to have been duly given to the Tenant. If
and to the extent requested by the Landlord, the Tenant shall give copies of all
Notices to the Landlord to holders of underlying mortgages and underlying leases
of which the Tenant has notice.

                                 ARTICLE FIFTEEN
                            Conditions of Limitation

      15.1. This Lease and the term and estate hereby granted are subject to the
limitation that:

            (a) if the Tenant shall default in the payment of any Rent and any
      such default shall continue for ten (10) days after notice,

            (b) if the Tenant shall default in observing any provision of
      Article Three or of subsection (e) or (f) of Section 6.1 and such default
      shall continue and shall not be remedied by the Tenant within three (3)
      business days (except that, with respect to any such default of any
      provision of clause (iv) of subparagraph (e) of Section 6.1. hereof, said
      period shall be twenty-four (24) hours) after notice,

            (c) if the Tenant shall default in observing any provision of this
      Lease (other than a default of the character referred to in subsection (a)
      or (b) of this Section), and if such default shall continue and shall not
      be remedied by the Tenant within thirty (30) days after notice or, if such
      default cannot for causes beyond the Tenant's control, with due diligence
      be cured within said period of thirty (30) days, if the Tenant (i) shall
      not, promptly upon the giving of such Notice, give the Landlord notice of
      the Tenant's intention to duly institute all steps necessary to remedy
      such default, (ii) shall not duly institute and thereafter diligently
      prosecute to completion all steps necessary to remedy the same, or (iii)
      shall not remedy the same within a reasonable time after the date of the
      giving of said notice by the Landlord, which period shall in no event
      exceed ninety (90) days,

            (d) if any event shall occur or any contingency shall arise whereby
      this Lease or the estate hereby granted or the unexpired balance of the
      full term of this Lease would, by operation of law or otherwise, devolve
      upon or pass to any person, firm or corporation other than the Tenant
      (except as permitted under Article Seven), or if the Tenant shall desert
      or abandon the Premises (whether or not the keys be surrendered or the
      rent is paid),

            (e) if any other lease held by the Tenant from the Landlord or any
      affiliate of the Landlord shall expire or terminate (whether or not the
      term thereof shall then have commenced) as a result of the default of the
      Tenant

<PAGE>   23
                                       20


      thereunder or of the occurrence of an event as therein provided (other
      than by expiration of the hill term thereof or pursuant to a cancellation
      or termination option therein contained or pursuant to provisions similar
      to those contained in the first sentence of Article Ten), or

            (f) when and to the extent permitted by law, if a petition in
      bankruptcy shall be filed by or against the Tenant, or if the Tenant shall
      make a general assignment for the benefit of its creditors, or the Tenant
      shall receive the benefit of any insolvency or reorganization act, or if a
      receiver or trustee is appointed for any portion of the Tenant's property
      and such appointment is not vacated within sixty (60) days, or if an
      execution or attachment shall be issued under which the Premises shall be
      taken or occupied by anyone other than the Tenant,

then in any of said cases the Landlord may give to the Tenant a notice of
intention to end the term of this Lease, and, if such notice is given, this
Lease and the term and estate hereby granted (whether or not the term shall
theretofore have commenced) shall terminate upon the expiration of seven (7)
days from the date the notice is deemed given with the same effect as if the
last of said seven (7) days were the date originally specified as the expiration
of the full term of this Lease, but the Tenant shall remain liable for damages
as provided in this Lease or pursuant to law. If this Lease shall have been
assigned, the term "Tenant", as used in subsections (a) to (f), inclusive, of
this Section 15.1, shall be deemed to include the assignee and the assignor or
either of them under any such assignment unless the Landlord shall, in
connection with such assignment, release the assignor from any further liability
under this Lease, in which event the term "Tenant", as used in said subsections,
shall not include the assignor so released.

                                 ARTICLE SIXTEEN
                              Re-entry by Landlord

      16.1. If this Lease shall terminate under Article Fifteen, or if the
Tenant shall default in the payment of any Rent on any date upon which the same
becomes due, and if such default shall continue for five (5) days after the
Landlord shall have given to the Tenant a notice specifying such default, the
Landlord or the Landlord's agents and servants may immediately or at any time
thereafter re-enter the Premises, or any part thereof in the name of the whole,
either by summary dispossess proceedings or by any suitable action or proceeding
at law, without being liable to indictment, prosecution or damages therefor, and
may repossess the same, and may remove any persons therefrom, to the end that
the Landlord may have, hold and enjoy the Premises again as and of its first
estate and interest therein. The words "re-enter", "re-entry", and "re-entering"
as used in this Lease are not restricted to their technical legal meanings.

      16.2. If this Lease shall terminate under the provisions of Article
Fifteen or if the Landlord undertakes any summary dispossess or other proceeding
or action or other measure for the enforcement of its right of re-entry (any
such termination of this Lease or undertaking by the Landlord being a "Default
Termination"), the Tenant shall thereupon pay to the Landlord the Rent up to the
time of such Default Termination, and shall likewise pay to the Landlord all
such damages which, by reason of such Default Termination, shall be payable by
the Tenant as provided in this Lease or pursuant to law. Also in the event of a
Default Termination the Landlord shall be entitled to retain all moneys, if any,
paid by the Tenant to the Landlord, whether as advance rent or as security for
rent, but such moneys shall be credited by the Landlord against any Rent due
from the Tenant at the time of such Default Termination or, at the Landlord's
option, against any damages payable by the Tenant as provided in this Lease or
pursuant to law.

      16.3. In the event of a breach or threatened breach on the part of the
Tenant of any of its obligations under this Lease, the Landlord shall also have
the right of injunction. The specified remedies to which the Landlord may resort
under this Lease are cumulative and are not intended to be exclusive of any
other remedies or means of redress to which the Landlord may lawfully be
entitled at any time, and the Landlord may invoke any remedy allowed at law or
in equity as if specific remedies were not provided for in this Lease.

<PAGE>   24
                                       21


                                ARTICLE SEVENTEEN
                                     Damages

      17.1. If there is a Default Termination of this Lease, the Tenant will pay
to the Landlord as damages, at the election of the Landlord, either:

            (a) a sum which, at the time of such Default Termination, represents
      the then present value (such computation to be made by using the then
      prevailing rate of most recently issued bonds or notes issued by the
      United States Treasury having a maturity closest to but not exceeding the
      period commencing with the day following the date of such Default
      Termination and ending with the date originally specified as the
      expiration date of this Lease (the "Remaining Period")) of the excess, if
      any, of (1) the aggregate of the fixed rent and the additional rent under
      Article Twenty-four (if any) which, had this Lease not so terminated,
      would have been payable under this Lease by the Tenant for the Remaining
      Period over (2) the aggregate rental value of the Premises for the same
      period, or

            (b) sums equal to the aggregate of the fixed rent and the additional
      rent under Article Twenty-four (if any) which would have been payable by
      the Tenant had this Lease not terminated by such Default Termination,
      payable upon the due dates therefor specified in this Lease following such
      Default Termination and until the date originally specified as the
      expiration of this Lease; provided, that if the Landlord shall relet all
      or any part of the Premises for all or any part of the Remaining Period
      (the Landlord having no obligation to so relet the Premises), the Landlord
      shall credit the Tenant with the net rents received by the Landlord from
      such reletting, such net rents to be determined by first deducting from
      the gross rents as and when received by the Landlord from such reletting
      the expenses incurred by the Landlord in terminating this Lease and
      re-entering the Premises and of securing possession thereof, as well as
      the expenses of reletting, including altering and preparing the Premises
      for new tenants, brokers' commissions, and all other expenses properly
      chargeable against the Premises and the rental therefrom in connection
      with such reletting, it being understood that any such reletting may be
      for a period equal to or shorter or longer than said period; provided,
      further, that (i) in no event shall the Tenant be entitled to receive any
      excess of such net rents over the sums payable by the Tenant to the
      Landlord, (ii) in no event shall the Tenant be entitled, in any suit for
      the collection of damages pursuant to this subsubsection (b), to a credit
      in respect of any net rents from a reletting except to the extent that
      such net rents are actually received by the Landlord prior to the
      commencement of such suit, and (iii) if the Premises or any part thereof
      should be relet in combination with other space, then proper apportionment
      on a square foot rentable area basis shall be made of the rent received
      from such reletting and of the expenses of reletting.

      17.2. For the purposes of this Article, the amount of additional rent
which would have been payable by the Tenant under Article Twenty-four shall, for
each Computation Year (as defined in Article Twenty-four) ending after such
Default Termination, be deemed to be an amount equal to the amount of additional
rent payable by the Tenant for the Computation Year immediately preceding the
Computation Year in which such Default Termination occurs or if the Default
Termination occurs prior to the end of the first Computation Year, then the
Landlord's reasonable estimate of what additional rent would have been had the
Lease commenced one year earlier, and in either case deemed increased each year
by the percentage increase in additional rent for the immediately preceding
Computation Year over the additional rent for the twelve-month period prior
thereto or, if the Lease term did not occur throughout such prior years,
Landlord's reasonable estimate of what such increase would have been had the
term occurred during such years. Suit or suits for the recovery of any damages
payable by the Tenant, or any installments thereof, may be brought by the
Landlord from time to time at its election, and nothing in this Lease shall be
deemed to require the Landlord to postpone suit until the date when the term of
this Lease would have expired but for such Default Termination.

      17.3. Nothing in this Lease shall be construed as limiting or precluding
the recovery by the Landlord against the Tenant of any sums or damages to which,
in addition to the damages specified above, the Landlord may lawfully be
entitled by reason of any default under this Lease on the part of the Tenant.

<PAGE>   25
                                       22


                                ARTICLE EIGHTEEN
                                Waivers by Tenant

      18.1. The Tenant, for itself and all other Tenant Parties, and on behalf
of any and all persons, firms, entities and corporations claiming through or
under any Tenant Party, including, without limitation, creditors of all kinds,
does hereby waive and surrender all right and privilege which they or any of
them might have under or by reason of any present or future law to redeem the
Premises or to have a continuance of this Lease for the full term hereby demised
after the Tenant is dispossessed or ejected therefrom by process of law or under
the terms of this Lease or after the expiration or termination of this Lease as
provided in this Lease or pursuant to law. The Tenant also waives (a) the right
of the Tenant to trial by jury in any summary dispossess or other proceeding
that may hereafter be instituted by the Landlord against the Tenant with respect
to the Premises or in any action that may be brought to recover rent, damages or
other sums payable under this Lease, and (b) the provisions of any law relating
to notice and/or delay in levy of execution in case of an eviction or dispossess
of a tenant for nonpayment of rent, and of any other law of like import now or
hereafter in effect. If the Landlord commences any such summary dispossess
proceeding, the Tenant will not interpose any counterclaim of whatever nature or
description in such proceeding, other than a compulsory counterclaim.

                                ARTICLE NINETEEN
                                Tenant's Removal

      19.1. Any personal property which shall remain in any part of the Premises
after the expiration or termination of the term of this Lease with respect to
such part shall be deemed to have been abandoned, and either may be retained by
the Landlord as its property or may be disposed of in such manner as the
Landlord may see fit at the Tenant's cost; provided, that the Tenant will, upon
request of the Landlord, remove from the Building any such personal property by
the later of the expiration or termination of this Lease or thirty (30) days
after the Landlord's request.

                                 ARTICLE TWENTY
                       Elevators, Cleaning, Services, etc.

      20.1. The Landlord will, at the Landlord's sole cost and expense, (i)
supply passenger elevator service during Business Hours to each floor, above the
street floor of the Building, which is served by the Building's passenger
elevators and on which the Premises are, or any portion thereof is, located,
with one of said elevators being subject to call for such service during hours
other than Business Hours, (ii) supply an elevator for the transmission of
freight to said floor or floors during Business Hours, (iii) subject to any
applicable policies or regulations adopted by any utility or governmental
authority, supply during Business Hours in the heating season heat for the
warming of the Premises and the public portions of the Building, (iv) subject to
any applicable policies or regulations adopted by any utility or governmental
authority, supply during Business Hours air conditioning (including cooling
during the cooling season as, an the Landlord's reasonable judgment, may be
necessary) and ventilation to all portions of the Premises, if any, which are
served by the Building's air conditioning and ventilation systems, and (v) clean
any portion of the Premises which is located on a floor above the street floor
of the Building except any such portion used exclusively for preparing,
dispensing or consumption of food or beverages or as an exhibition area or
classroom or for storage, shipping room, mail room or similar purposes or which
is a toilet (other than a toilet shown on any diagram attached hereto as Exhibit
A) or a shop or is used for a trading floor or exclusively for operation of
computer, data processing, reproduction, duplicating or similar equipment. In
order for said air conditioning system to function properly, the Tenant must, to
the extent they are missing therefrom, install window blinds or shades on all
windows of the Premises and must lower and close such window blinds or shades on
all windows facing the sun whenever said air conditioning system is in operation
and the Tenant will at all times comply with all regulations and requirements
which the Landlord may reasonably prescribe for the proper functioning and
protection of said air conditioning system. No representation is made by

<PAGE>   26
                                       23


the Landlord with respect to the adequacy or fitness of such air conditioning or
ventilation to maintain temperatures that may be required for, or because of,
the operation of any computer, data processing or other equipment of the Tenant
and where air conditioning or ventilation is required for any such purpose and
the Landlord assumes no responsibility, and shall have no liability for any loss
or damage however sustained, in connection therewith. The cleaning specification
annexed hereto as Exhibit B set forth substantially the extent and scope of the
cleaning to be performed by the Landlord in the Premises as hereinabove provided
in this paragraph. Unless otherwise provided in this Lease, "Business Hours",
means the generally customary daytime business hours of the Tenant (but not
before 8:00 A.M. or after 6:00 P.M.) of days other than Saturdays, Sundays and,
as established by the Landlord, holidays. The air conditioning to be provided
during the cooling season with respect to said portions of the Premises served
by said air conditioning system shall be such as to provide a temperature of not
more than 76 degrees Fahrenheit dry bulb (plus or minus 2 degrees) and 50% (plus
or minus 5%) relative humidity when the outside temperature is not more than 93
degrees Fahrenheit dry bulb. If any one or more the following conditions apply
to a portion of the Premises, then the maintenance of the above temperature
standard shall not apply to that portion of the Premises, namely (i) average
occupancy over one person per 100 square feet, (ii) an average monthly
electrical load in excess of 4-watts per useable square foot, and/or (iii)
renovations performed by the Tenant which interfere with a properly designed
flow of cool conditioned air. When the outside temperature exceeds 93 degrees,
the air conditioning system shall be operated at full capacity but without being
required to maintain a particular temperature. At all times other than described
above, the Building's systems shall be operated by the Landlord during the
season when heat is required to maintain an average temperature of 72 degrees
Fahrenheit (plus or minus 2 degrees) throughout the Premises. The air circulated
through the ducts of the air conditioning system of the Building serving the
Premises shall consist of an average amount of fresh air to meet applicable
ventilation codes.

      20.2. The Landlord agrees that the Tenant may install a supplemental air
conditioning system in the Premises having a maximum capacity of fifteen (15)
tons subject to the terms and conditions of this Lease, including but not
limited to, the provisions of Article Thirty and Article 6.1(e). In addition,
the Landlord shall provide to the Tenant up to fifteen (15) tons of air
conditioning capacity in the form of chilled water for the Tenant's supplemental
air conditioning. If the Tenant receives chilled water, the Tenant shall pay the
Landlord's charges (as same may exist from time to time) for its actual usage
(the Landlord's current charge is $750 per ton, per year). The Tenant shall
install a meter to measure its usage in a location approved by the Landlord. The
Tenant shall also pay the Landlord's connection charge of $150 per ton, with a
minimum charge of $1,500, for such chilled water. Such Landlord charges are
subject to change at any time during the term of this Lease, any increase to be
limited to the direct pass through of any increase in the Landlord's cost for
electricity and water used to provide chilled water.

      20.3. The Landlord shall, when and to the extent reasonably requested by
the Tenant, furnish additional elevator, heating, air conditioning, ventilating
and/or cleaning services upon such reasonable terms and conditions as shall be
determined by the Landlord, including the payment by the Tenant of the
Landlord's reasonable charge therefor. The Tenant will also pay the Landlord's
reasonable charge for (a) any additional cleaning of the Premises required
because of the carelessness or indifference of any Tenant Party or because of
the nature of any Tenant Party business, and (b) the removal of any refuse and
rubbish of any Tenant Party from the Premises and the Building, except
wastepaper and similar discarded material placed by the Tenant in wastepaper
baskets and left for emptying as an incident to the Landlord's normal cleaning
of the Premises. If the cost to the Landlord for cleaning the Premises shall be
increased due to the use of any part of the Premises during hours other than
Business Hours or due to there being installed in the Premises, at the request
of or by any Tenant Party, any materials or finish other than those which are of
the standard adopted by the Landlord for the Building, the Tenant shall pay to
the Landlord an amount equal to such increase in cost.

      20.4. All or any of the elevators in the Building may, at the option of
the Landlord, be manual or automatic elevators, and the Landlord shall be under
no obligation to furnish an elevator operator or starter for any automatic
elevator, but if the Landlord shall furnish any elevator operator or starter for
any automatic elevator, the Landlord may discontinue furnishing such elevator
operator or starter.

<PAGE>   27
                                       24


      20.5. The Landlord reserves the right, without liability to the Tenant and
without constituting any claim of constructive eviction, to stop or interrupt
any heating, elevator, escalator, lighting, ventilating, air conditioning,
power, water, cleaning or other service and to interrupt the use of any Building
facilities, at such times as may be necessary and for as long as may reasonably
be required by reason of accidents, strikes, the making of repairs, alterations
or improvements, inability to secure a proper supply of fuel, steam, water,
electricity, labor or supplies, or by reason of any other cause beyond the
reasonable control of the Landlord; provided, that any such stoppage or
interruption for the purpose of making any discretionary alteration or
improvement shall be made at such times and in such manner as shall not
unreasonably interfere with the Tenant's use of the Premises; and provided,
further, that the Landlord will make all such repairs, alterations and
improvements with due dispatch subject to causes beyond the Landlord's
reasonable control. Notwithstanding anything in the foregoing provisions of this
Section 20.5, to the contrary, if due to the negligence or intentional act of
the Landlord any Essential Service which the Landlord is required to provide to
the Tenant under this Lease is interrupted for a period of fifteen (15)
consecutive business days, then, to the extent the Landlord receives insurance
proceeds for loss of rental income resulting from such interruption of an
Essential Service, (a) if the entire Premises is rendered untenantable or
otherwise cannot be used for the conduct of the Tenant's business, and (b) the
Tenant does not in fact use the entire Premises for the conduct of its business,
the Tenant shall be entitled to an abatement of the fixed rent for each day
after such fifteen (15) business day period that the entire Premises shall
remain untenantable and the Tenant does not use any portion thereof for the
conduct of its business. For the purposes of this Article, "Essential Service"
shall mean electric, heat, air conditioning, ventilation and at least one
elevator serving the Premises.

                               ARTICLE TWENTY-ONE
                    Lease Contains All Agreements-No Waivers

      21.1. This Lease contains all of the understandings relating to the
leasing of the Premises and the Landlord's obligations in connection therewith
and neither the Landlord nor any agent or representative of the Landlord has
made or is making, and the Tenant in executing and delivering this Lease is not
relying upon, any warranties, representations, promises or statements
whatsoever, except to the extent expressly set forth in this Lease. All
understandings and agreements, if any, heretofore had between the parties are
merged in this Lease, which alone fully and completely expresses the agreement
of the parties.

      21.2. The failure of the either party to insist in any instance upon the
strict keeping, observance or performance of any provision of this Lease or to
exercise any election in this Lease shall not be construed as a waiver or
relinquishment for the future of such provision, but the same shall continue and
remain in full force and effect. No waiver or modification by either party of
any provision of this Lease shall be deemed to have been made unless expressed
in writing and signed by such party. No surrender of possession of the Premises
or of any part thereof or of any remainder of the term of this Lease shall
release the Tenant from any of its obligations under this Lease unless accepted
by the Landlord in writing. The receipt and retention by the Landlord of Rent
from anyone other than the Tenant shall not be deemed a waiver of the breach by
the Tenant of any provision in this Lease, or the acceptance of such other
person as a tenant, or a release of the Tenant from its further observance of
the provisions of this Lease. The receipt and retention by the Landlord of Rent
with knowledge of the breach of any provision of this Lease shall not be deemed
a waiver of such breach.

                               ARTICLE TWENTY-TWO
                           Parties Bound; Exculpation

      22.1. The provisions of this Lease shall bind and benefit the respective
successors, assigns and legal representatives of the parties to this Lease
except that (1) no violation of the provisions of Article Seven shall operate to
vest any rights in any successor, assignee or legal representative of the Tenant
and (2) the provisions of this Article shall not be construed as modifying the
conditions of limitation contained in Article Fifteen. The obligations of the
Landlord under this Lease shall not, however, be binding upon the Landlord
herein named (or

<PAGE>   28
                                       25


any transferee of its interest in the Building or the Premises) with respect to
the period (i) subsequent to the transfer of its interest in the Building or the
Premises (a lease of the entire interest being deemed such a transfer), or (ii)
subsequent to the expiration or earlier termination of the term of any
underlying lease to which this Lease and the term and estate hereby granted may
be subject and subordinate and wherein the lessor thereunder has agreed to
recognize this Lease in case the term of said underlying lease expires or
terminates prior to the expiration or termination of the term of this Lease if
the Landlord would not then be entitled to terminate this Lease pursuant to said
Article Fifteen or to exercise any dispossess remedy provided for in this Lease
or by law; and in any such event those covenants shall, subject to Article
Thirteen, thereafter be binding upon the transferee of such interest in the
Building or the Premises or the lessor under said underlying lease, as the case
may be, until the next such transfer of such interest.

      22.2. The Tenant shall look solely to the Landlord's interest in the Land
and the Building (or the proceeds thereof) for the satisfaction of any monetary
claim under this Lease, or for the collection of any judgment (or other judicial
process) based thereon, and no other property or assets of the Landlord (or any
affiliate, shareholder, director, officer, employee, partner, agent,
representative, or beneficiary of the Landlord, disclosed or undisclosed) shall
be subject to levy, execution or other enforcement procedure for the
satisfaction of such claim or judgment (or other judicial process).

                              ARTICLE TWENTY-THREE
                    Curing Tenant's Defaults-Additional Rents

      23.1. If the Tenant shall default in the observance of any provision of
this Lease, the Landlord, without thereby waiving such default, may perform the
same for the account and at the expense of the Tenant (a) immediately or at any
time thereafter and without notice in the case of emergency or in case such
default unreasonably interferes with the use by any other tenant of any space in
the Building or with the efficient operation of the Building or will result in a
violation of any Requirement applicable to the Land, the Building or the
Premises or any part thereof, to the Tenant's use thereof or to the Tenant's
observance of any provision of this Lease, or in a cancellation of an insurance
policy maintained by the Landlord, and (b) in any other case if such default
continues after thirty (30) days from the date of the giving by the Landlord of
notice of the Landlord's intention so to perform the same, unless such default
cannot, for causes beyond the Tenant's control, with due diligence be cured
within said period of thirty (30) days and the Tenant (i) shall, promptly upon
the giving of such notice, give the Landlord notice of the Tenant's intention to
duly institute all steps necessary to remedy such default, (ii) shall duly
institute and thereafter diligently prosecute to completion all steps necessary
to remedy the same, and (iii) shall remedy the same within a reasonable time
after the date of the giving of such notice by the Landlord, which period shall
in no event exceed ninety (90) days; provided, however, notwithstanding the
provisions of clause (b) above, that if the Tenant's default constitutes a
default under any underlying lease or underlying mortgage and the lessor or
mortgagee thereof notifies the Landlord of such default, then if the cure period
afforded the Tenant extends beyond the tenth day preceding the end of the cure
period permitted to the Landlord under the underlying lease or underlying
mortgage, the Landlord may so notify the Tenant, in which event the Landlord's
right to cure the Tenant's default will commence upon such tenth day. All
reasonable costs and reasonable expenses incurred by the Landlord in connection
with any such performance by it for the account of the Tenant and all reasonable
costs and reasonable expenses, including reasonable counsel fees and
disbursements incurred by the Landlord in any action or proceeding (including
any summary dispossess proceeding) brought by the Landlord to enforce any
obligation of the Tenant under this Lease and/or right of the Landlord in or to
the Premises, shall be paid by the Tenant to the Landlord upon demand. Except as
expressly provided to the contrary in this Lease, all costs and expenses which,
pursuant to this Lease (including the rules and regulations referred to in this
Lease) are incurred by the Landlord and payable to it by the Tenant and all
charges, amounts and sums payable to the Landlord by the Tenant for any
property, material, labor, utility or other services which, pursuant to this
Lease or at the request and for the account of the Tenant, are provided,
furnished or rendered by the Landlord shall become due and payable by the Tenant
to the Landlord in accordance with the terms of bills therefor to be rendered by
the Landlord to the Tenant. If any cost, expense, charge, amount or sum referred
to in this Section or elsewhere in this Lease is not paid when due as provided
in this

<PAGE>   29
                                       26


Lease, the same shall become due by the Tenant as additional rent under this
Lease. If any Rent or damages payable under this Lease is not paid when due, the
same shall bear interest at the rate of 5% above the prime commercial rate of
The Chase Manhattan Bank (National Association) or any successor thereto for
unsecured borrowings in effect at the time, per annum (but in no event at a rate
in excess of that permitted by law) from the due date thereof until paid and the
amount of such interest shall be deemed additional rent under this Lease. If
there is a nonpayment by the Tenant of any such additional rent and/or any other
additional rent becoming due under this Lease, the Landlord, in addition to any
other right or remedy, shall have the same rights and remedies as in the case of
default by the Tenant in the payment of the fixed rent. If the Tenant is in
arrears in payment of Rent, the Tenant waives the Tenant's right, if any, to
designate the items against which any payments made by the Tenant are to be
credited, and the Landlord may apply any payments made by the Tenant to any
items the Landlord sees fit, irrespective of and notwithstanding any designation
or request by the Tenant as to the items against which any such payments shall
be credited. The Landlord reserves the right, without liability to the Tenant
and without constituting any claim of constructive eviction, to suspend
furnishing or rendering to the Tenant any property, material, labor, utility or
other service, wherever the Landlord is obligated to furnish or render the same
at the expense of the Tenant (exclusive of any service which the Landlord
furnishes for no additional charge pursuant to Article Five and Article Twenty
hereof, and exclusive of alternating electric current furnished pursuant to the
first paragraph of Article Five hereof), in the event that (but only so long as)
the Tenant is in arrears in paying the Landlord therefor at the expiration of
five (5) days after the Landlord shall have given to the Tenant notice demanding
the payment of such arrears.

                              ARTICLE TWENTY-FOUR
            Adjustments for Changes in Landlord's Costs and Expenses

      24.1. If for any Computation Year, the R.E. Tax Share of the Real Estate
Taxes shall be greater than Base Real Estate Taxes, or 110% of the O.E. Share of
the Cost of Operation and Maintenance shall be greater than 110% of the Base
COM, then the Tenant shall pay to the Landlord, as additional rent, an amount
equal to the product obtained by multiplying such excess or excesses by the
Tenant's Area.

      24.2. In order to provide for current payments on account of the
additional rent which may be payable to the Landlord pursuant to Section 24.1
for any Computation Year, the Tenant agrees to make such payments on account of
said additional rent for and during such Computation Year, as the case may be,
as follows:

            (a) With respect to Real Estate Taxes, the Tenant shall pay its
      share thereof in two semiannual installments in advance on the first day
      of June and December, each equal to the product of the Tenant's Area
      multiplied by one-half of the excess of the R.E. Tax Share of the Real
      Estate Taxes for the Tax Year in which the Landlord's corresponding tax
      payment falls over the Base Real Estate Taxes, it being understood that if
      the tax bill for the following Tax Year is not received in time to bill
      the June 1 payment, the Landlord may estimate the payment due on June 1
      based on the Landlord's estimate of the Real Estate Taxes for such
      following Tax Year. If, upon issuance of the tax bill for such following
      Tax Year, such estimated amount results in an underpayment, the Tenant
      shall pay to the Landlord the amount of the underpayment. If, upon
      issuance of the tax bill for such following Tax Year, such estimated
      amount results in an overpayment, the Landlord shall either pay to the
      Tenant an amount equal to the overpayment or permit the Tenant a credit
      for such amount against future Rent payments; provided, however, that if
      any rent abatement is then in effect pursuant to the terms and conditions
      of this Lease, and no Rent is due the Landlord from the Tenant, the
      Landlord shall pay to the Tenant the amount of any such overpayment. If
      there shall be any increase in Real Estate Taxes for any Tax Year, whether
      during or after such Tax Year, or if there shall be any decrease in the
      Real Estate Taxes for any Tax Year, whether during or after such Tax Year,
      the Tenant shall pay its share of any increase, or, to the extent the
      decrease does not reduce the RE. Tax Share of Real Estate Taxes below the
      Base Real Estate Taxes, receive its share of any decrease, substantially
      in the same manner as provided in the preceding two sentences. If during
      the term of the Lease, Real Estate Taxes are required to be paid (either
      to the appropriate taxing authorities or as a tax escrow to the holder of
      an underlying lease or an underlying mortgage), on any other date or dates
      than as presently required, then the Tenant's payments

<PAGE>   30
                                       27


      toward Real Estate Taxes shall be correspondingly accelerated or revised
      so that such payments are due at least thirty (30) days prior to the date
      payments are due to the taxing authorities or to the holder of an
      underlying lease or underlying mortgage.

            (b) With respect to Cost of Operation and Maintenance, the Tenant
      shall pay an amount each month equal to the product of the Tenant's Area
      multiplied by 1/12th of the excess of 110% of the O.E. Share of the Cost
      of Operation and Maintenance for such Computation Year as reasonably
      estimated by the Landlord over 110% of the Base COM, the installment for
      each calendar month to be due and payable upon the receipt from the
      Landlord of a bill for the same. If, as finally determined, the amount of
      additional rent payable by the Tenant to the Landlord pursuant to this
      Subsection for such Computation Year shall be greater than (resulting in
      an underpayment) or be less than (resulting in an overpayment) the
      aggregate of all the installments so paid on account to the Landlord by
      the Tenant for such Computation Year, then, promptly after the receipt of
      the bill for such Computation Year and, in performance of its obligations
      under Section 24.1, the Tenant shall, in case of such an underpayment, pay
      to the Landlord an amount equal to such underpayment or the Landlord
      shall, in case of such an overpayment, either pay to the Tenant an amount
      equal to such overpayment or permit the Tenant a credit for such amount
      against future rent payments.

      24.3. As used in this Article:

            (a) "Computation Year" shall mean each calendar year in which occurs
      any part of the term of this Lease and, in the case of a Default
      Termination of this Lease, in which would have occurred any part of the
      full term of this Lease except for such Default Termination.

            (b) "Tax Year" shall mean the twelve (12) month period commencing
      July 1 of each year, or such other twelve (12) month period as may be duly
      adopted as the fiscal year for real estate tax purposes in The City of New
      York.

            (c) "Tenant's Area" shall mean the number of square feet in the
      rentable area of the Premises.

            (d) "R.E. Tax Share" shall mean a fraction whose numerator is one
      and whose denominator is the number of square feet of the rentable area of
      the Center (excluding from such denominator the number of rentable square
      feet in any portion of the Center (i) not leased to the Tenant and for
      which Real Estate Taxes are not payable in full, or (ii) for which the
      Real Estate Taxes are payable directly in whole or in part by any person,
      firm or corporation other than the Landlord, without reimbursement by the
      Landlord or (iii) at the Landlord's election, constituting a condominium
      unit not wholly or partially leased to the Tenant); provided that the
      Landlord may elect to limit the denominator to only the number of square
      feet in the rentable area of the Building (which the Landlord advises the
      Tenant currently contains 586,370 rentable square feet determined in
      accordance with Section 1.6. hereof) if the Landlord makes a similar
      election for all buildings it owns in the Center. The Landlord advises the
      Tenant that the Center currently contains 6,784,036 rentable square feet
      (determined in accordance with Section 1.6. hereof) for purposes of
      measuring R.E. Tax Share.

            (e) "O.E. Share" shall mean a fraction whose numerator is one and
      whose denominator is the number of square feet in the rentable area of all
      buildings in the Center exclusive of the rentable area of any such
      building or any structure on any such building operated and maintained by
      and at the expense of any person, firm or corporation (other than the
      Landlord or, at Landlord's election, any affiliate of Landlord) or of any
      theater or garage located in the Center; provided that the Landlord may
      elect to limit the denominator to only the number of square feet in the
      rentable area of the Building if the Landlord makes a similar election for
      all buildings it owns in the Center. The Landlord advises the Tenant that
      the Center currently contains 7,414,055 rentable square feet for purposes
      of measuring O.E. Share (determined in accordance with in Section 1.6.
      hereof).

            (f) "Real Estate Taxes" shall mean the taxes and assessments imposed
      upon the Center (to the extent the Landlord does not make the election in
      the proviso of subsection (d) above), including without limitation
      assessments made as a result of the Center or part thereof being within a
      business improvement district (other
<PAGE>   31
                                       28


      than any interest or penalties imposed in connection therewith), and all
      expenses, including fees and disbursements of counsel and experts,
      reasonably incurred by, or reimbursable by, the Landlord in connection
      with any application for a reduction in the assessed valuation for the
      Center or for a judicial review thereof (but in no event shall expenses be
      included in Base Real Estate Taxes). If due to a future change in the
      method of taxation any franchise, income, profit or other tax shall be
      levied against the Landlord in substitution in whole or in part for or in
      lieu of any tax which would otherwise constitute a Real Estate Tax, such
      franchise, income, profit or other tax shall be deemed to be a Real Estate
      Tax for the purposes of this Lease. Real Estate Taxes shall not include
      any portion thereof (i) allocable to an area not leased to the Tenant and
      for which what would otherwise be Real Estate Taxes are not payable in
      full (ii) payable directly, in whole or in part, by a person, firm, entity
      or corporation other than the Landlord, without reimbursement by the
      Landlord, or (iii) allocable to a condominium unit that the Landlord
      elects pursuant to clause (d) above to exclude from the calculation of
      R.E. Tax Share.

            (g) "Cost of Operation and Maintenance" shall mean the actual cost
      incurred by the Landlord or its affiliates with respect to the ownership,
      operation, maintenance and repair of the Center (to the extent the Center
      is included in the calculation of O.E. Share, it being understood that if
      less than the entire Center is included in such calculation, then Cost of
      Operation and Maintenance shall include a portion of the common area
      expenses of the Center in the same proportion as the rentable area of the
      building or buildings included in the calculation of O.E. Share bears to
      the aggregate rentable area in all buildings in the Center) and the curbs
      and sidewalks adjoining the same, including, without limitation, the cost
      incurred for air conditioning; mechanical ventilation; heating; interior
      and exterior cleaning; rubbish removal; window washing (interior and
      exterior, including inside partitions); elevators; escalators; hand tools
      and other moveable equipment to the extent same are not required to be
      capitalized in accordance with good accounting practice; porter and matron
      service; electric current, steam, water and other utilities; association
      fees and dues, other than to political organizations or parties;
      protection and security service; repairs; maintenance; compliance with any
      Preservation Agreement to the extent same are not required to be
      capitalized in accordance with good accounting practice; fire, extended
      coverage, boiler, sprinkler, apparatus, rental income, public liability
      and property damage insurance; supplies; wages, salaries, disability
      benefits, pensions, hospitalization, retirement plans and group insurance
      respecting service and maintenance employees, building superintendents,
      concierges, managers, their assistants and clerical staffs, and persons
      engaged in supervision of the foregoing; uniforms and working clothes for
      such employees and the cleaning thereof; expenses imposed pursuant to any
      collective bargaining agreement with respect to such employees; payroll,
      social security, unemployment and other similar taxes with respect to such
      employees; sales, use and other similar taxes; vault charges; franchise
      fees payable in connection with the concourse levels of the Center; water
      rates; sewer rents; charges of any independent contractor who does any
      work with respect to the operation, maintenance and repair of the Center
      and the curbs and sidewalks adjoining the same; legal, accounting and
      other professional fees; decorations; and the annual depreciation or
      amortization over the useful life thereof of costs, including financing
      costs, incurred for any equipment, device or other capital improvement
      made or acquired which is either intended as a laborsaving measure or to
      effect other economies in the operation, maintenance or repair of the
      Center and said curbs and sidewalks (but only to the extent that the
      annual benefits anticipated to be realized therefrom are reasonably
      related to the annual amount to be amortized) or which is required by any
      Requirement; provided, that the term "Cost of Operation and Maintenance"
      shall not include (1) Real Estate Taxes, special assessments, franchise
      taxes or taxes imposed upon or measured by the income or profits of the
      Landlord, (2) except for depreciation and amortization specifically
      provided for in this subsection, the cost of any item which is, or should
      in accordance with good accounting practice be, capitalized on the books
      of the Landlord, (3) the cost of any electricity furnished to the Premises
      or any other space in the Center demised to other tenants, (4) the cost of
      any work or service performed for any tenant of space in the Center
      (including the Tenant) at such tenant's cost and expense, (5) any costs
      incurred with respect to any theater or garage located in the Center, (6)
      management fees, if such fees are in excess of independent management
      agents' fees customary in the City of New York for first class office
      buildings, (7) any legal fees, brokerage expenses, advertising expenses or
      renting commissions incurred in leasing space, (8) any interest on or
      amortization of any indebtedness of the Landlord for borrowed money, (9)
      any rent payable under any underlying lease, (10) any cost to the extent
      that the Landlord is reimbursed for such costs (other than through the
      payment of rent), (11) the costs of subdivision, layout and finish of any
      space in the Center performed in connection with the

<PAGE>   32
                                       29


      occupancy of such space by a new tenant or in connection with a renewal of
      a new lease for such space with the existing tenant thereof, (12) any
      fines or penalties assessed against the Landlord as a result of any
      governmental authority, (13) any costs incurred by the Landlord as a
      result of the gross negligence, willful misconduct or wrongful acts of any
      of its employees, or (14) the cost of any salary payable to, or the cost
      of any fringe benefits in connection with, the Chairman of the Board, the
      President, or any Vice President (other than any Senior Vice President in
      the Operating Division) of the Landlord and their respective secretaries.
      If during any period for which the Cost of Operation and Maintenance is
      being computed the Landlord is not for all or any part of such period
      furnishing any particular work or service (the cost of which if performed
      by the Landlord would constitute a Cost of Operation and Maintenance) to a
      portion of the Center due to the fact that such portion is not leased to a
      tenant or that the Landlord is not obligated to perform such work or
      service in such portion, then the amount of the Cost of Operation and
      Maintenance for such period shall be deemed, for the purposes of this
      Article, to be increased by an amount equal to the additional Cost of
      Operation and Maintenance which would reasonably have been incurred during
      such period by the Landlord if it had furnished such work or service.

            (h) "Base Real Estate Taxes" shall mean the R.E. Tax Share of the
      Real Estate Taxes for the Tax Year beginning on July 1, 1994 and ending on
      June 30, 1995.

            (i) "Base COM" shall mean the O.E. Share of the Cost of Operation
      and Maintenance for the Computation Year beginning on January 1, 1994 and
      ending on December 31, 1994.

      24.4. If the term commencement date shall be a day other than a January 1
or the date fixed for the expiration of the full term of this Lease shall be a
day other than December 31, or if there is any abatement of the fixed rent
payable under this Lease (other than any abatement under Article One hereof) or
any termination of this Lease (other than a Default Termination), or if there is
any increase or decrease in the Tenant's Area, then in each such event in
applying the provisions of this Article with respect to any Tax Year or
Computation Year in which such event occurred, appropriate adjustments shall be
made to reflect the result of such event on a basis consistent with the
principles underlying the provisions of this Article, taking into consideration
(i) the portion of such Tax Year or Computation Year, as the case may be, which
shall have elapsed prior to or after such event, (ii) the rentable area of the
Premises affected thereby, and (iii) the duration of such event.

      24.5. The Tenant shall not (and hereby waives any and all rights it may
now or hereafter have to) institute or maintain any action, proceeding or
application in any court or other body having the power to fix or review
assessed valuations, for the purpose of reducing the Real Estate Taxes.

      24.6. In the event the Landlord fails to bill the Tenant for Tenant's
share of Real Estate Taxes or Cost of Operation and Maintenance by the time such
amounts would otherwise be due and payable hereunder, the Tenant shall pay the
amount most recently billed for the item in question, subject to subsequent
adjustment to reflect the correct amount due. In the event of an overpayment by
the Tenant hereunder, the Landlord shall refund any excess payment made by the
Tenant promptly after the correct amount due is determined.

      24.7. When requested by the Tenant within one hundred twenty (120) days
following the receipt by it of any Escalation Statement, the Landlord, in
substantiation of its determination of the amounts set forth in said Escalation
Statement, will furnish to the Tenant such additional information as reasonably
may be required for such purpose, and, as may be necessary for the verification
of such information; it being expressly understood that (i) the Landlord shall
be under no duty to preserve any such records, or any data or material related
thereto, beyond such time as shall be its customary practice with respect
thereto, and (ii) the Tenant shall covenant and agree to keep such information
confidential for its use only for the purposes stated herein. For purposes of
this Article, "Escalation Statement" shall mean a final statement setting forth
the amount payable by the Tenant or the Landlord, as the case may be, for a
specified Computation Year pursuant to this Article.

<PAGE>   33
                                       30


                               ARTICLE TWENTY-FIVE
                                  Miscellaneous

      25.1. If the Landlord shall consent to the omission or removal of any part
of, or the insertion of any door (other than to a public corridor) or other
opening in, any wall separating the Premises from other space adjoining the
Premises, then (a) the Tenant shall be deemed to have assumed responsibility for
all risks (including, without limitation, damage to, or loss or theft of,
property) incident to the use of said door or other opening or the existence
thereof (unless due to the Landlord's gross negligence or willful misconduct),
and shall indemnify and save the Indemnitees harmless from and against any
claim, demand or action for, or on account of, any such loss, theft or damage,
and (b) upon the expiration or termination of this Lease or any lease of said
adjoining space, the Landlord may enter the Premises and close up such door or
other opening by erecting a wall to match the wall separating the Premises from
said adjoining space, and the Tenant shall pay the reasonable cost thereof and
such work may be done during Business Hours and while the Tenant is in occupancy
of the Premises and the Tenant shall not be entitled to any abatement of fixed
rent or other compensation on account thereof; provided, that nothing shall be
deemed to vest the Tenant with any right or interest in, or with respect to,
said adjoining space, or the use thereof, and the Tenant hereby expressly waives
any right to be made a party to, or to be served with process or other notice
under or in connection with, any proceeding which may hereafter be instituted by
the Landlord for the recovery of the possession of said adjoining space.

      25.2. Without incurring any liability to the Tenant, the Landlord may
permit access to the Premises and open the same, whether or not the Tenant shall
be present, upon demand of any receiver, trustee, assignee for the benefit of
creditors, sheriff, marshal or court officer entitled to, or reasonably
purporting to be entitled to, such access for the purpose of taking possession
of, or removing, the Tenant's property or for any other purpose (but this
provision and any action by the Landlord hereunder shall not be deemed a
recognition by the Landlord that the person or official making such demand has
any right or interest in or to this Lease, or in or to the Premises), or upon
demand of any representative of the fire, police, building, sanitation or other
department of the city, state or federal government.

      25.3. If an excavation shall be made upon any land adjacent to the
Building, or shall be authorized to be made, the Tenant shall afford to the
person causing or authorized to cause such excavation a license to enter upon
the Premises for the purpose of doing such work as said person shall deem
necessary to preserve the Building from injury or damage, all without any claim
for damages or indemnity against the Landlord or diminution or abatement of
rent.

      25.4. The Tenant shall not be entitled to exercise any right of
termination or other option granted to it by this Lease at any time when the
Tenant is in default beyond any applicable notice and grace periods under this
Lease. With respect to any such exercise, time shall be of the essence.

      25.5. The headings of the Articles of this Lease are for convenience only
and are not to be considered in construing said Articles.

      25.6. As used in this Section, the term "facility" means stores,
restaurants, cafeterias, rest rooms, and any other facility of a public nature
in the Building. The Tenant will not discriminate by segregation or otherwise
against any person or persons because of race, creed, color, sex (except as
appropriate in the case of rest rooms) or national origin in furnishing, or by
refusing to furnish, to such person or persons the use of any facility in the
Premises, including any and all services, privileges, accommodations, and
activities provided thereby. The Tenant's noncompliance with the provisions of
this Section shall constitute a material breach of this Lease. In the event of
such noncompliance, the Landlord may take appropriate action to enforce
compliance, may terminate this Lease in accordance with the provisions of this
Lease, or may pursue such other remedies as may be provided by law. In the event
of termination, the Tenant shall be liable to the Landlord for damages in
accordance with the provisions of this Lease.

<PAGE>   34
                                       31


      25.7. If the Tenant holds-over in the Premises after the expiration or
termination of this Lease without the consent of the Landlord, the Tenant shall:

            (a) pay as hold-over rental for each month of the hold-over tenancy
      an amount equal to the greater of (i) one and one-half times the fair
      market rental value of the Premises for such month (as reasonably
      determined by Landlord) or (ii) one and one-half times the Rent which
      Tenant was obligated to pay for the month immediately preceding the
      expiration or termination of this Lease;

            (b) be liable to the Landlord for (i) any payment or rent concession
      which Landlord may be required to make to any tenant obtained by the
      Landlord for all or any part of the Premises (a "New Tenant") in order to
      induce such New Tenant not to terminate its lease by reason of the
      holding-over by the Tenant and (ii) the loss of the benefit of the bargain
      if any New Tenant shall terminate its lease by reason of the holding-over
      by the Tenant; and

            (c) indemnify the Landlord against all claims for damages by any New
      Tenant.

      No holding-over by the Tenant, nor the payment to the Landlord of the
amounts specified above, shall operate to extend the term of this Lease.

      25.8. Any obligation of the Landlord or the Tenant which by its nature or
under the circumstances can only be, or by the provisions of this Lease may be,
performed after the expiration or earlier termination of this Lease, and any
liability for a payment which shall have accrued to or with respect to any
period ending at the time of such expiration or termination, unless expressly
otherwise provided in this Lease, shall survive the expiration or earlier
termination of this Lease.

      25.9. If any provision of this Lease or the application thereof to any
person or circumstance shall, to any extent, be invalid or unenforceable, the
remainder of this Lease, or the application of such provision to persons or
circumstances other than those as to which it is invalid or unenforceable, shall
not be affected thereby, and each provision of this Lease shall be valid and be
enforced to the fullest extent permitted by law.

      25.10. Notwithstanding anything to the contrary herein contained, no term
or provision of this Lease which may be or become inconsistent with the
provisions of Section 9-1.1 of the Estates, Powers and Trusts Law of the State
of New York, or any successor thereto in effect during the term of this Lease,
shall be operative following twenty-one years after the death of the last to die
of those descendants of John D. Rockefeller, Sr. in being on the date of this
Lease.

      25.11. It is the intention of the Landlord and the Tenant to create the
relationship of landlord and tenant, and no other relationship whatsoever, and
nothing herein shall be construed to make the Landlord and the Tenant partners
or joint venturers, or to render either party hereto liable for any of the debts
or obligations of the other party.

      25.12. The Landlord and the Tenant acknowledge that (i) improvements
(including Fixtures) made or installed by the Tenant in the Premises do not
constitute consideration for the granting of this Lease to the Tenant and (ii)
there has been no adjustment in the fixed or additional rent payable under this
Lease on account of such improvements (including Fixtures).

      25.13. If there is any payment required to be made by the Tenant under
this Lease for which no time period is stated within which the payment must be
made, such payment shall be made within thirty (30) days after demand by the
Landlord.

<PAGE>   35
                                       32


                               ARTICLE TWENTY-SIX
                                    Security

      26.1. The Tenant shall at all times maintain on deposit with the Landlord
cash in the amount of $131,502.00 as security for the full and faithful
keeping, observance and performance of all of the provisions of this Lease
provided to be kept, observed or performed by the Tenant (expressly including,
without being limited to, the payment as and when due of the Rent and any other
sums or damages payable by the Tenant under this Lease) and the payment of any
and all other damages for which the Tenant shall be liable by reason of any act
or omission contrary to any of said provisions. If the Landlord invests the
deposit, any interest earned thereon, less the Landlord's reasonable
administrative fee associated with holding and investing the deposit (which in
no event shall exceed one-half of one percent (.5%)), shall be deemed added to
the deposit to be held as additional security hereunder and shall be treated the
same as the initial deposit. If at any time the Tenant shall be in default in
the payment of any Rent and/or any other sums or damages or shall otherwise be
in default in the keeping, observance or performance of any of the provisions of
this Lease, then at the Landlord's election, the cash on deposit with it as
aforesaid may be applied by the Landlord to the payment of the Rent, other sums
or damages in respect to which the Tenant is so in default and/or, if the Tenant
is otherwise in default in the keeping, observing or performing as aforesaid of
any of the provisions of this Lease, said cash on deposit may be applied by the
Landlord to the payment of such costs and expenses as the Landlord shall incur
in curing any such default without relieving the Tenant of its obligation to the
extent such amount applied is inadequate. If at any time the Landlord is
required to return or repay to the Tenant, for any reason in connection with the
bankruptcy or insolvency of the Tenant, any fixed rent, additional rent and/or
any other sums paid by the Tenant to the Landlord under the Lease, then, at the
Landlord's election, the security may be applied by the Landlord to offset such
return or repayment. If as a result of any such application, the amount of cash
on deposit with the Landlord shall at any time be less than that hereinabove
specified, the Tenant shall forthwith deposit with the Landlord additional cash
in an amount equal to the deficiency. If, at the expiration or earlier
termination of this Lease, all of said Rent other sums or damages, costs and
expenses shall have been paid by the Tenant to the Landlord and the Tenant shall
not be in default in the keeping, observance or performance of any other
provision of this Lease, then the Landlord shall return to the Tenant all, or
such part of the cash, if any, then on deposit with the Landlord pursuant to
this Section 26.1.

      26.2. In lieu of maintaining on deposit with the Landlord cash as
aforesaid, the Tenant may maintain with the Landlord a clean, unconditional
irrevocable letter of credit issued by a New York clearing house bank in the
amount of $131,502.00 drawable upon by the Landlord, either in partial draws or
in one full draw, at any time when cash on deposit with it as aforesaid might
and to the extent could have been applied by the Landlord pursuant to the first
paragraph of this Article upon the delivery to said bank of the Landlord's
certificate to such effect, and otherwise containing terms and conditions
satisfactory to the Landlord. The Landlord shall use any amount so drawn in
accordance with said first paragraph. If at any time the sum of the amount
drawable pursuant to said letter of credit plus any cash on deposit with the
Landlord pursuant to this Article shall be less than the amount of $131,502.00,
the Tenant agrees forthwith to deposit with the Landlord a new letter of credit
complying herewith or cash equal to such deficiency.

      26.3. If any letter of credit so maintained with the Landlord provides
that the amount drawable pursuant to said letter of credit shall cease to be
available on a date prior to November 30, 2004, the Tenant shall, at least 30
days prior to the date specified in said letter of credit as being the date on
which such drawable amount will cease to be available, either furnish to the
Landlord a renewal or extension of said letter of credit, a new letter of credit
complying herewith, or deposit with the Landlord such amount of cash as shall,
when added to any cash then on deposit with the Landlord, equal the amount of
$131,502.00. Failure to comply with the provisions of the preceding sentence
prior to the commencement of said 30-day period shall be deemed to be a default
under this Lease and the Landlord may, at any time during said 30-day period,
draw upon such letter of credit and retain as security hereunder the amount so
drawn.

      26.4. All amounts deposited by the Tenant with the Landlord pursuant to
this Article shall, at all times prior to their application as provided in this
Article, be maintained on deposit by the Landlord in an interest bearing

<PAGE>   36
                                       33


account in a federally insured (a) commercial bank, (b) savings bank or (c)
savings and loan association, and, so long as the Tenant is not in default in
the due keeping, observance or performance of any of the terms and conditions of
this Lease, the Landlord will remit the interest accrued thereon to the Tenant
at least once each year.

                              ARTICLE TWENTY-SEVEN
                              Brokerage Commission

      27.1. The Tenant represents that the only broker with which it has dealt
in connection with this Lease is Rockefeller Center Management Corporation. The
Tenant shall indemnify and save harmless the Indemnitees from and against all
liability, claims, suits, demands, judgments, costs, interest and expenses
(including reasonable counsel fees and disbursements incurred in the defense
thereof) to which the Indemnitees may be subject or suffer by reason of any
claim made by any person, firm or corporation other than the aforementioned
broker for any commission, expense or other compensation as a result of the
execution and delivery of this Lease or the demising of the Premises by the
Landlord to the Tenant pursuant to this Lease.

      27.2. The Landlord shall pay any brokerage commission due to Rockefeller
Center Management Corporation by reason hereof pursuant to the provisions of a
separate agreement, if any.

                              ARTICLE TWENTY-EIGHT
                                 Quiet Enjoyment

      28.1. If, and so long as, the Tenant performs each and every provision in
this Lease on the part of the Tenant to be performed, the Tenant shall quietly
enjoy the Premises without hindrance or molestation by the Landlord or by any
other person lawfully claiming the same, subject, however, to the provisions of
this Lease and to the Qualified Encumbrances.

                               ARTICLE TWENTY-NINE
                              Hazardous Substances

      29.1. The Tenant shall not (i) cause or permit to be brought to the
Building, the Land or the Center any hazardous substances, (ii) cause or permit
the storage or use of hazardous substances in any manner not permitted by any
Requirements applicable to the Land, the Building or the Premises or any part
thereof, to the Tenant's use thereof or to the Tenant's observance of any
provision of this Lease, or (iii) cause or permit the escape, disposal or
release of any hazardous substances on or in the vicinity of the Building, Land
or Center; provided, that nothing herein shall prevent the Tenant's use of any
hazardous substances customarily used in the ordinary course of office work if
such use is for such ordinary course of office work and is in accordance with
all Requirements applicable to the Land, the Building or the Premises or any
part thereof, to the Tenant's use thereof or to the Tenant's observance of any
provision of this Lease.

      29.2. "Hazardous substances" are (i) any "hazardous wastes" as defined by
the Resource, Conservation and Recovery Act of 1976 (42 U.S.C. Section 6901 et
seq.), as amended, and regulations promulgated thereunder; (ii) any "hazardous,
toxic or dangerous waste, substance or material" specifically defined as such in
(or for purposes of) the Comprehensive Environmental Response, Compensation and
Liability Act of 1980 (42 U.S.C. Section 9601 et seq.) as amended, and
regulations promulgated thereunder; and (iii) any hazardous, toxic or dangerous
chemical, biological or other waste, substance or material as defined in any
so-called "superfund" or "superlien" law or any other federal, state or local
statute, law, ordinance, code, rule, regulation, order or decree regulating,
relating to or imposing liability or standards of conduct concerning such waste,
substance or material; including, without limiting the generality of the
foregoing, asbestos, radon, urea formaldehyde, polychlorinated biphenyls, and
petroleum products including gasoline, fuel oil, crude oil and various
constituents of such

<PAGE>   37
                                       34


products. Without limiting the generality of Section 6.1(j) hereof, the Tenant
agrees that the covenants and warranties contained in this Article are included
within the matters as to which the Indemnitees shall be indemnified pursuant to
said Section 6.1(j).

      29.3. The covenants contained in this Article shall survive the expiration
or earlier termination of this Lease.

                                 ARTICLE THIRTY
                                 Work by Tenant

      30.1. The Tenant shall, not less than thirty (30) days prior to the term
commencement date, submit to the Landlord, for the Landlord's review and
consent, complete architectural, electrical and mechanical working drawings and
specifications and sample boards showing the proposed renovation of the Premises
(herein called "the Work Area") as desired by the Tenant and in keeping with the
landmark status of, and consistent with the design, construction and equipment
of the Building and the Center and in conformity with its standards, all in such
form and in such detail as may be reasonably required by the Landlord. In the
event the Tenant removes, or materially alters fifty percent (50%) or more of
the ceiling area in the Work Area in connection with such renovation, the Tenant
shall provide and install a sprinkler system for the Work Area in full
compliance with Local Law 5/1973, as amended (hereafter "Local Law 5"); except
for the sprinkler tap to the Premises and the sprinkler loop therein, both of
which shall be provided and installed by the Landlord after the term
commencement date, and otherwise subject to Article Two, at the Landlord's sole
cost and expense. The working drawings, specifications and sample boards to be
submitted to the Landlord as aforesaid shall be prepared by a competent
architect licensed in the State of New York (in consultation with a competent
engineer licensed in the State of New York where required by the nature of the
work), reasonably satisfactory to the Landlord, who shall be engaged by the
Tenant and who, at the Tenant's expense, shall furnish all architectural and
engineering services necessary, including, without limitation, hydraulic
calculations, for the preparation of said working drawings, specifications and
sample boards and in connection with securing the aforesaid consent thereof by
the Landlord and with the securing by the Tenant of such consents as by reason
of the nature of the work shown on said working drawings, specifications and
sample boards, may be required from the Department of Buildings of the City of
New York and any other governmental or quasi-governmental authorities,
including, without limitation, Landmarks Preservation Commission of the City of
New York.

      30.2. If the Landlord shall not consent to any working drawing,
specification or sample board as submitted by the Tenant, the Landlord shall
with reasonable promptness, but in any event within twenty (20) business days of
the Landlord's receipt of such drawings or specifications, notify the Tenant
thereof and of the particulars of such revisions therein as are reasonably
required by the Landlord for the purpose of obtaining its said consent and as
promptly as reasonably possible after being so informed by the Landlord, the
Tenant shall submit to the Landlord, for the Landlord's consent (which consent
shall not be unreasonably withheld or delayed), a working drawing, specification
or sample board, as the case may be, incorporating such revisions or
incorporating such modifications thereto as are suggested by the Tenant and
approved by the Landlord (said working drawings and specifications, as so
consented to, being herein called "the Working Drawings"). Any such consent by
the Landlord shall not be deemed to be a representation or warranty that the
same is properly designed to perform the function for which it is intended or
complies with any applicable Requirement, but only that the work required
thereby is compatible with the design and structure of the Building.

      30.3. Such renovation shall be performed in accordance with, and subject
to all of the terms and conditions of this Lease (including, but not limited to,
subparagraph (e) of Section 6.1 hereof except that the Tenant shall not be
obligated to pay to the Landlord the Landlord's charges for supervising such
renovation). Upon the consent by the Landlord of the Working Drawings, the
Tenant shall proceed with due dispatch to cause the work as shown on such
Working Drawings to be completed at the Tenant's sole cost and expense.

      30.4. The workmen and the contractors performing the work and the manner,
terms and conditions upon which the same is performed shall be satisfactory to
and approved by the Landlord and such workmen and

<PAGE>   38
                                       35


contractors shall be approved or disapproved by the Landlord within the same
time and in the same manner as the Landlord approves or disapproves the Working
Drawings. The work shall at all times comply with (a) all applicable
Requirements having jurisdiction with respect thereto, and (b) with the
reasonable rules, regulations and guidelines of the Landlord pertaining to the
performance thereof.

      30.5. Within thirty (30) days after substantial completion of the work,
the Tenant shall deliver to the Landlord (i) copies of paid receipts certified
by an officer of the Tenant, (ii) general releases and waivers of lien from all
consultants, contractors, subcontractors and materialmen involved in the
performance of the work and the materials furnished in connection therewith,
(iii) a certificate from the Tenant's architect certifying that the work has
been completed in accordance with this Lease, all applicable rules and
regulations of the Landlord, all Requirements and the Working Drawings, and (iv)
record drawings and specifications of the Premises reflecting the renovation as
provided in clause (iv), subparagraph (e) of Section 6.1. Notwithstanding the
foregoing, but in all events subject to the Tenant's obligation to keep the
Premises and the Building free of liens, the Tenant shall not be required to
deliver to the Landlord any general release or waiver of lien, as required by
the preceding sentence, if the Tenant shall be disputing in good faith the
payment which would otherwise entitle the Tenant to such release or waiver,
provided that the Tenant shall keep the Landlord advised in a timely fashion of
the status of any such dispute and the basis therefor and the Tenant shall
deliver to the Landlord the general release or waiver of lien when any such
dispute is settled.

      30.6. The Landlord agrees that upon receipt by it of evidence satisfactory
to it (as provided in Section 30.5. above) of the completion of such work in a
manner reasonably satisfactory to the Landlord, and upon the furnishing by the
Tenant to the Landlord of the evidence (as provided in Section 30.5. above) of
the payment therefor by the Tenant, the Landlord shall reimburse to the Tenant
the lesser of (i) the payment of the actual cost of such work, or (ii)
$75,000.00.

                               ARTICLE THIRTY-ONE
                                   Sprinklers

      31.1. If during the initial renovation of the Work Area the Tenant does
not remove or materially alter the ceiling as described in Section 30.1. hereof
and provide and install a sprinkler system in the Work Area as provided therein,
then, in the event the Tenant at anytime thereafter during the term of this
Lease removes or materially alters fifty percent (50%) or more of the ceiling in
the Work Area, the Tenant shall provide and install a sprinkler system for the
Work Area. Such installation shall be performed in accordance with and subject
to all of the terms and conditions of this Lease (including but not limited to
Article Six hereof). The Landlord will, subject to Article Two, be responsible
for providing and installing a sprinkler tap to the Work Area and a sprinkler
loop therein, at its sole cost and expense which sprinkler tap and loop shall be
connected to the Building's base building water supply system.

      31.2. The Tenant agrees to permit the Landlord to enter the Work Area in
order to install the sprinkler tap and sprinkler loop and the Landlord may do
such work during Business Hours while the Tenant is in occupancy of the Work
Area. The Tenant shall not be entitled to any abatement of fixed rent or other
compensation by reason thereof.

                               ARTICLE THIRTY-TWO
                           Asbestos Removal by Tenant

      32.1. The Landlord shall, prior to the term commencement date, cause to be
conducted at its cost and expense, by a licensed inspector selected by the
Landlord an inspection for the purpose of detecting the presence of asbestos in
the Work Area. Upon the completion of such inspection the Landlord shall submit
a copy of the inspection report to the Tenant.

<PAGE>   39
                                       36


      32.2. In the event that the asbestos inspection report indicates that
asbestos removal is required, the Tenant shall submit to the Landlord, for the
Landlord's approval, complete specifications detailing the proposed asbestos
removal from the Work Area, consistent with the design, construction and
equipment of the Building and in conformity with its standards, all in such form
and in such detail as may be reasonably required by the Landlord. In no event
shall any such specifications include removal of asbestos from the Building's
core or perimeter, from behind perimeter heating units or from shafts, columns,
beams or wet stacks, if any. The specifications to be submitted to the Landlord
as aforesaid shall be prepared by a competent engineer licensed in the State of
New York, reasonably satisfactory to the Landlord, who shall be engaged by the
Tenant and who, at the Tenant's expense, shall furnish all architectural and
engineering services necessary for the preparation of said specifications and in
connection with securing the aforesaid approval thereof by the Landlord and with
the securing by the Tenant of such approvals as by reason of the nature of the
work shown on said specifications, may be required from the Department of
Buildings of the City of New York and any other governmental authorities. The
Tenant shall furnish three estimates from qualified contractors of the proposed
cost of the asbestos removal along with the specifications licensed in the State
of New York to perform such asbestos removal.

      32.3. Should the Landlord not accept any estimate or specifications as
submitted by the Tenant, the Landlord shall, with reasonable promptness, notify
the Tenant thereof and of the particulars of such revisions therein as are
reasonably required by the Landlord for the purpose of obtaining its said
approval and as promptly as reasonably possible after being so informed by the
Landlord the Tenant shall submit to the Landlord, for the Landlord's approval
(which approval shall not be unreasonably withheld), a revised estimate
acceptable to the Landlord and/or a specification, as the case may be,
incorporating such revisions or incorporating such modifications thereto as are
suggested by the Tenant and approved by the Landlord (said specifications, as so
approved, being herein called "the Specifications"). Any such approval by the
Landlord shall not be deemed to be a representation or warranty that the same is
properly designed to perform the function for which it is intended or complies
with any Requirements, but only that the work required thereby will not
interfere with the systems of the Building and is compatible with the design and
structure of the Building.

      32.4. Such removal shall be performed in accordance with, and subject to
all of the terms and conditions of this Lease (including, but not limited to,
Article Six hereof). Upon the approval by the Landlord of the Specifications and
the revised estimate, the Tenant shall proceed with due dispatch to cause the
work as shown on such approved Specifications to be properly supervised,
monitored and completed at the Tenant's sole cost and expense.

      32.5. The Landlord agrees that upon receipt by it of evidence satisfactory
to it of the completion of such work by the Tenant in a manner satisfactory to
the Landlord and upon the furnishing by the Tenant to the Landlord of (i) the
discharge of any lien filed in connection with such work, and (ii) certificates
issued by a licensed independent testing laboratory (other than the entity
performing the asbestos removal) indicating the satisfactory removal of
asbestos; the Landlord shall reimburse to the Tenant that amount which is the
lesser of (a) the estimate as approved by the Landlord, subject to any change
orders approved by the Landlord, or (b) the actual cost to the Tenant of such
work.

                              ARTICLE THIRTY-THREE
                              Termination by Tenant

      33.1. The Tenant may, effective as of September 30, 1999, elect to
terminate this Lease and the term and estate hereby granted (the "Termination
Date"), by giving to the Landlord notice thereof on or prior to September 30,
1998, as to which date time is of the essence. The Tenant shall also be required
in connection with such termination to make a Termination Payment to the
Landlord concurrent with the giving of such notice. For purposes of this
Article, "Termination Payment" shall mean $628,346.25.

      33.2. In the event of the giving of such notice and the making as
aforesaid of the Termination Payment, this Lease and the term and estate hereby
granted (unless the same shall have expired sooner pursuant to any of the

<PAGE>   40
                                       37


other conditions of limitation or provisions of this Lease or pursuant to law)
shall terminate on the Termination Date with the same effect as if the
Termination Date were the date hereinbefore specified for the expiration of the
full term granted by this Lease. The Tenant shall terminate its occupancy of the
Premises not later than the Termination Date and the fixed rent hereunder shall
be apportioned as of such date.

      33.3. With respect to the foregoing termination, the Tenant shall complete
and timely submit all returns and questionnaires relating to New York City and
State real property transfer tax laws and any other applicable real property
transfer or gains tax laws (the taxes which are the subject of such laws are
hereinafter collectively called "Transfer Taxes"). The Tenant shall timely pay
all Transfer Taxes, if any, and shall deliver evidence, reasonably acceptable to
the Landlord, of such payment simultaneously to the Landlord. The Tenant shall
indemnify and hold harmless the Landlord from all losses, liabilities, interest,
judgments, suits, demands, damages, costs and expenses (including attorneys'
fees and disbursements incurred in the defense thereof) which the Landlord may
incur by reason of the Tenant's failure to complete and timely submit any and
all Transfer Tax returns and questionnaires and/or the Tenant's failure to
timely pay any and all Transfer Taxes. The provisions of this paragraph shall
survive the expiration of the Lease.

                               ARTICLE THIRTY-FOUR
                                   Extra Space

      34.1. The parties agree and understand that all of the space on the 24th
and 26th floors of the Building (all or any part of such space hereinafter
called an "Extra Space") is currently vacant. After the Landlord completes the
initial leasing of all or any part of the Extra Space, and if this Lease shall
at the time be in full force and effect and the term hereof shall not have
expired or terminated, the Landlord will not enter into a lease with any other
person, firm or corporation covering the demise of any Extra Space until a
period of thirty (30) days shall have elapsed after the Landlord shall have
notified the Tenant that such Extra Space is or will be available for leasing.
The Landlord agrees that, if so requested by the Tenant, it will negotiate in
good faith with the Tenant during said period of thirty (30) days for the
leasing of such Extra Space to the Tenant upon terms mutually satisfactory to
the Landlord and the Tenant, which shall, with the exception of the financial
terms, be substantially the terms and conditions of this Lease. If such mutually
satisfactory terms with respect to any Extra Space have not been agreed to by
the Landlord and the Tenant in a written agreement, fully executed and
unconditionally delivered by both parties by the end of such period of thirty
(30) days, then the Landlord shall have no further obligation to the Tenant with
respect to such Extra Space.

      34.2. Notwithstanding anything hereinbefore contained to the contrary, the
Extra Space shall not be deemed to be available for leasing to the Tenant if (i)
the Landlord renews or extends, in whole or in part, the then existing lease
covering the Extra Space or leases all or any part of the Extra Space to the
then present lessee of the Extra Space, or (ii) the Extra Space has been
previously offered to the Tenant and the Tenant has not exercised such option or
the Landlord and the Tenant failed to achieve mutually satisfactory terms with
respect to a prior offer of the Extra Space.

                               ARTICLE THIRTY-FIVE
                               Assignment of Lease

      35.1. In connection with a one time only bona fide sale of the Tenant's
business, an assignment of this Lease by the Tenant, to a person, firm or
corporation (herein called the "Assignee"), shall not be deemed a violation of
Article Seven hereof, provided that:

                  (a) the Tenant shall notify the Landlord of the name of the
            proposed Assignee, such information as to the proposed Assignee's
            business, financial responsibility and standing as the Landlord may
            reasonably require. Such Assignee shall be, in the Landlord's
<PAGE>   41
                                       38


reasonable judgment, of a character as is in keeping with the standards in those
respects for the Building; and

      (b) the Landlord shall approve such assignment or transfer, which approval
will not be unreasonably withheld or delayed upon the express conditions that:

            (I) such Assignee shall have the financial resources necessary to
      meet its obligation under the Lease and the Assignee shall supply such
      financial information to the Landlord as may be reasonably necessary for
      the Landlord to determine the same and if, in the Landlord's reasonable
      judgment, the Assignee does not have the necessary financial resources,
      then the Landlord reserves the right to require the posting of such
      security or guarantee as the Landlord deems reasonably necessary to secure
      the obligations under this Lease;

            (II) the Tenant, as assignor, and the Assignee will execute and
      deliver to the Landlord an agreement in form and substance satisfactory to
      the Landlord whereby the Tenant shall be released from its obligations
      under the Lease and the Assignee shall agree to be bound by and upon all
      of the terms and conditions set forth in this Lease, and for which the
      Tenant shall pay to the Landlord a reasonable processing charge, not to
      exceed $2,500.00; and

            (III) the Tenant and the Assignee shall agree that the Assignee
      shall not, without the prior approval of the Landlord pursuant to this
      Article, further assign or transfer the Lease or the Premises or any part
      thereof.

                            (Continued on next page)

<PAGE>   42

                                       39

      In Witness Whereof, the Landlord and the Tenant have duly executed this
Lease as of the day and year first above written.


                                     ROCKEFELLER CENTER PROPERTIES
                                     By: ROCKEFELLER CENTER MANAGEMENT
                                     CORPORATION, its Agent

                                     By:
                                       -------------------------------
                                                        Vice President

Attest:


-----------------------------------
                Assistant Secretary


                                     John A. Levin & Co., Inc.

                                     By: John A. Levin
                                       -------------------------------
                                                             President

      Attest:

      /s/ Carol L. Novak
      --------------------------------
                             Secretary

<PAGE>   43

                             RULES AND REGULATIONS

      1. The rights of the Tenant in the sidewalks, entrances, corridors,
stairways, elevators and escalators of the Building are limited to ingress to
and egress from the Premises for any Tenant Party, and the Tenant shall not
invite to the Premises, nor permit the visit thereto by, persons in such numbers
or under such conditions as to interfere with the use and enjoyment by others of
the sidewalks, entrances, corridors, stairways, elevators, escalators or any
other facilities of the Building. Fire exits and stairways are for emergency use
only, and they shall not be used for any other purpose by any Tenant Party. The
Landlord shall have the right to regulate the use of and operate the public
portions of the Building, as well as portions furnished for the common use of
the tenants, in such manner as it deems best for the benefit of the tenants
generally.

      2. The Landlord may refuse admission to the Building outside of Business
Hours to any person not having a pass issued by the Landlord or not properly
identified, and may require all persons admitted to or leaving the Building
outside of Business Hours to register. Any person whose presence in the Building
at any time shall, in the judgment of the Landlord, be prejudicial to the
safety, character, reputation and interests of the Building or of its tenants
may be denied access to the Building or may be ejected therefrom. In case of
invasion, riot, public excitement or other commotion the Landlord may prohibit
all access to the Building during the continuance of the same, by closing doors
or otherwise, for the safety of the tenants or protection of property in the
Building. The Landlord shall, in no way, be liable to the Tenant for damages or
loss arising from the admission, exclusion or ejection of any person to or from
the Premises or the Building under the provisions of this rule. The Landlord may
require any person leaving the Building with any package or other object to
exhibit a pass from the tenant from whose Premises the package or object is
being removed, but the establishment or enforcement of such requirement shall
not impose any responsibility on the Landlord for the protection of the Tenant
against the removal of property from the Premises of the Tenant.

      3. The Tenant shall not obtain or accept for use in the Premises ice,
drinking water, food, beverage, towel, linen, uniform, barbering, bootblacking
or similar or related services from any persons not authorized by the Landlord
to furnish such services. Such services shall be furnished only at such hours,
in such places within the Premises and under such regulations as may be fixed by
the Landlord.

      4. Where any damage to the public portions of the Building or to any
portions used in common with other tenants is caused by any Tenant Party, the
cost of repairing the same shall be paid by the Tenant upon demand.

      5. Except in the case of a shop, no lettering, sign, advertisement,
trademark, emblem, notice or object shall be displayed in or on the windows or
doors, or on the outside of the Premises, or at any point inside the Premises
where the same might be visible outside the Premises, except that the name of
the Tenant may be displayed on the entrance door of the Premises, subject to the
approval of the Landlord as to the location, size, color and style of such
display. The inscription of the name of the Tenant on the door of the Premises
shall be done by the Landlord and the expense thereof shall be paid by the
Tenant to the Landlord.

      6. No awnings or other projections of any kind over or around the windows
or entrances of the Premises shall be installed by the Tenant, and only such
window blinds and shades as are approved by the Landlord shall be used in the
Premises. Linoleum, tile or other floor covering shall be laid in the Premises
only in a manner approved by the Landlord.

      7. The Landlord shall have the right to prescribe the weight and position
of safes and other objects of excessive weight, and no safe or other object
whose weight exceeds the lawful load for the area upon which it would stand
shall be brought into or kept upon the Premises. If, in the judgment of the
Landlord, it is necessary to distribute the concentrated weight of any safe or
heavy object, the work involved in such distribution shall be done in such
manner as the Landlord shall determine and the expense thereof shall be paid by
the Tenant. The

<PAGE>   44

moving of safes and other heavy objects shall take place only upon previous
notice to, and at times and in a manner approved by, the Landlord, and the
persons employed to move the same in and out of the Building shall be acceptable
to the Landlord. No machines, machinery or electrical or electronic equipment or
appliances of any kind shall be placed or operated so as to disturb other
tenants. Freight, furniture, business equipment, merchandise and packages of any
description shall be delivered to and removed from the Premises only in the
freight elevators and through the service entrances and corridors, and only
during hours and in a manner approved by the Landlord.

      8. No noise, including the playing of any musical instrument, radio or
television, which, in the judgment of the Landlord, might disturb other tenants
in the Building, shall be made or permitted by the Tenant. No animal shall be
brought into or kept in the Building or the Premises. No dangerous, inflammable,
combustible or explosive object or material shall be brought into or kept in the
Building by the Tenant or with the permission of the Tenant, except as permitted
by law and the insurance companies insuring the Building or the property
therein. The Tenant shall not cause or permit any odors of cooking or other
processes, or any unusual or other objectionable odors, to permeate in or
emanate from the Premises. Any cuspidors or containers or receptacles used as
such in the Premises, shall be emptied, cared for and cleaned by the Tenant.

      9. No additional locks or bolts of any kind shall be placed upon any of
the doors or windows in the Premises and no lock on any door shall be changed or
altered in any respect. Duplicate keys for the Premises and toilet rooms shall
be procured only from the Landlord, and the Tenant shall pay to the Landlord the
Landlord's reasonable charge therefor. Upon the expiration or termination of the
Lease, all keys of the Premises and toilet rooms shall be delivered to the
Landlord.

      10. All entrance doors in the Premises shall be left locked by the Tenant
when the Premises are not in use. No door (other than a door in an interior
partition of the Premises) shall be left open at any time.

      11. The Landlord reserves the right to rescind, alter or waive any rule or
regulation at any time prescribed by the Landlord when, in its judgment, it
deems it necessary, desirable or proper for its best interest or for the best
interests of the tenants, and no recision, alteration or waiver of any rule or
regulation in favor of one tenant shall operate as a recision, alteration or
waiver in favor of any other tenant. The Landlord shall not be responsible to
the Tenant for the nonobservance or violation by any other tenant of any of the
rules or regulations at any time prescribed by the Landlord.

      12. The Tenant shall promptly notify the Landlord of any inspection of the
Premises by governmental agencies having jurisdiction over matters involving
health or safety.

      13. The Tenant shall be responsible for maintaining the Premises rodent
and insect free. Extermination services shall be provided by the Tenant on a
monthly basis and additionally as required by the Landlord.

      14. All food storage areas shall be adequately protected against vermin
entry by a contractor approved in advance by the Landlord.

      15. Drain pipes shall be kept free of obstructions and operable at all
times.

      16. Exit signs shall be illuminated, and other exit identification shall
be operable, at all times.

      17. Emergency lighting, including battery components, shall be in good
working condition at all times.

<PAGE>   45

                                    EXHIBIT B

                             CLEANING SPECIFICATIONS

GENERAL

            All hard surface flooring to be dust mopped nightly. All other floor
         maintenance shall be done at Tenant's expense.

            All carpeting and rugs to be carpet swept nightly and vacuumed twice
      monthly.

            Hand dust nightly all furniture tops and exposed surfaces of
      shelves, ledges and bookcases within reach.

            Empty and wipe clean all wastebaskets nightly and remove the
      contents thereof from the Premises.

            Empty and wipe clean all ash trays and screen all sand urns nightly.

            Wash clean all water fountains and coolers nightly.

            Dust all door and other ventilating louvers within reach, as
      necessary.

            Dust all telephones as necessary.

            Sweep all private stairway structures nightly.

            All windows are to be washed approximately five times per year.

            Do all high dusting approximately once every three months, namely:

                        Dust all pictures, frames, charts, graphs and similar
                  wall hangings not reached in nightly cleaning.

                        Dust clean all vertical surfaces, such as walls,
                  partitions, doors and bucks and other surfaces not reached in
                  nightly cleaning.

                        Dust clean all pipes, ventilating and conditioning
                  louvers, ducts, diffusers, high mouldings and other high areas
                  not reached in nightly cleaning.

                        Dust all lighting fixtures, including exterior surfaces
                  of diffusers and enclosures.

                        Dust all venetian blinds.

CORE LAVATORIES

            Sweep and wash all lavatory floors nightly, using disinfectants.

            Wash and disinfect all basins, bowls and urinals nightly.

            Wash and disinfect all toilet seats nightly.

<PAGE>   46

            Hand dust and clean, washing where necessary, all partitions, tile
      walls, dispensers and receptacles in all lavatories and restrooms nightly.

            Empty paper towel receptacles and transport wastepaper from the
      Premises nightly.

            Fill toilet tissue holders nightly (tissue to be furnished by
      Landlord).

            Empty sanitary disposal receptacles nightly.

            Wash interior of wastecans and receptacles at least once a week.

            If core lavatory is within Tenant's space, the soap and towel
      dispenser will be filled at Tenant's direction at Tenant's expense. If
      core lavatory is on a public corridor, the soap and towel dispenser will
      be maintained by Landlord.

PUBLIC AND CORE AREAS AND ELEVATORS

            Dust mop all floors nightly and wash once a week. Spray buff
      resilient tile flooring on a semi-monthly schedule.

            Inspect, maintain and keep clean firehoses, extinguishers and
      similar equipment as necessary.

            Spot wash wall of corridors and public stairways as necessary.

            Empty and screen all cigarette urns daily.

            Mop floor in public stairwells once per week.

            Dust elevator doors and frames, and Building directories as
      required.

                                    *********

      "Nightly", as used herein, shall be exclusive of Saturdays, Sundays and
holidays.

      "Holidays", as used herein, shall mean any day which is specified as a
holiday for all union members in the applicable building service union agreement
(as distinguished from days which are specified as holidays in such union
agreement on an individual basis such as a member's birthday or a death of a
relative).

<PAGE>   47

                                    EXHIBIT C

                               Consent to Sublease

      ROCKEFELLER CENTER PROPERTIES, a partnership, having an office at No. 1230
Avenue of the Americas, New York, N.Y. 10020 (herein called "the landlord"),
hereby consents to the subletting by (herein called "the Tenant"), to (herein
called "the Subtenant"), of a portion not exceeding square feet of rentable area
of the premises on the Floor of the Building known as in Rockefeller Center, in
the Borough of Manhattan, New York, N.Y., for a term expiring not later than
which premises are now leased and demised by the Landlord to the Tenant by that
certain lease dated (said lease, as the same may have been and may hereafter be
amended by any indentures or agreements supplemental thereto, is herein called
"the Lease'), such consent being subject to and upon the following terms and
conditions, to each of which the Tenant and the Subtenant expressly agree:

      (1) Nothing herein contained shall be construed to modify, waive, impair
or affect any of the terms or conditions contained in the Lease (except as may
be herein expressly provided), or to waive any breach of the Tenant in the due
keeping, observance or performance thereof.

      (2) The Tenant shall be and remain liable and responsible for the due
keeping, performance and observance throughout the term of the Lease, of all of
the terms and conditions therein set forth on the part of the Tenant to be kept,
performed and observed and for the payment of the fixed rent, percentage rent
(if any), additional rent and all other sums now and/or hereafter becoming
payable thereunder, expressly including as such additional rent, any and all
charges for any property, material, labor, utility or other services furnished
or rendered by the Landlord in or in connection with the premises demised by the
Lease, whether for, or at the request of, the Tenant or the Subtenant.

      (3) The sublease to cover the space to be sublet by the Tenant to the
Subtenant shall be subject and subordinate at all times to the Lease, and to all
of the terms and conditions of the Lease and of this Consent, and the Subtenant
shall not do, permit or suffer anything to be done in, or in connection with the
Subtenant's use or occupancy of, the portion of the premises so sublet which
would violate any of said terms and conditions.

      (4) The Subtenant shall not, without the prior written consent of the
Landlord, assign the aforesaid sublease or under-sublet the space so sublet or
any part thereof.

      (5) This Consent shall not be construed as a consent by the Landlord to,
or as permitting, any other or further subletting by the Tenant.

      (6) The portion of the premises so sublet shall (subject to all of the
terms and conditions of the Lease) be used solely for

<PAGE>   48

      (7) Upon the expiration or any earlier termination of the term of the
Lease with respect to the portion of the premises so sublet or in case of the
surrender of the Lease by the Tenant to the Landlord, the aforesaid sublease and
the term and estate thereby granted shall terminate as of the effective date of
such expiration, termination or surrender, and the Subtenant shall vacate such
portion of the premises on such date.

      (8) A true and complete copy of the aforesaid sublease and a true and
complete copy of each amendment thereto shall be delivered to the Landlord
within 10 days after the execution and delivery thereof by the parties thereto;
it being understood that the Landlord shall not be deemed to be a party to said
sublease or any such amendment nor bound by any of the terms or conditions
thereof and that neither the execution and delivery of this Consent nor the
receipt by the Landlord of a copy of said sublease or a copy of any such
amendment shall be deemed to change any provision of this Consent or to be a
consent to, or an approval by the Landlord of, any term or condition contained
in said sublease or any such amendment.

<PAGE>   49

      IN WITNESS WHEREOF, the parties hereto have cause these presents to be
duly executed as of

                                   ROCKEFELLER CENTER PROPERTIES,
                                   By ROCKEFELLER CENTER MANAGEMENT
                                   CORPORATION, its Agent


                                   By
                                     ---------------------------------
Attest:                                                 Vice President
                                                 LANDLORD

-----------------------------
          Assistant Secretary


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


                                    By
                                     ---------------------------------
Attest:                                                 Vice President
                                                 TENANT

-----------------------------
          Assistant Secretary


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


                                    By
                                     ---------------------------------
Attest:                                                 Vice President
                                                 SUBTENANT

-----------------------------
          Assistant Secretary

<PAGE>   50

                            SECOND AMENDMENT TO LEASE

            This SECOND AMENDMENT TO LEASE, dated as of January 22, 1998 (this
"Amendment"), between RCPI TRUST, a Delaware business trust having an office c/o
Tishman Speyer Properties, L.P., 45 Rockefeller Plaza, New York, New York 10111
("Landlord"), and LEVIN MANAGEMENT CO., INC., a Delaware corporation having an
office at One Rockefeller Plaza, New York, New York 10020 ("Tenant").

                              W I T N E S S E T H :

            WHEREAS, Landlord's predecessor in interest, Rockefeller Center
Properties, and Tenant's predecessor-in-interest, John A. Levin & Co., Inc.,
entered into that certain Lease, dated December 20, 1993, amended by
Supplemental Indenture, dated March 2,1995, and First Amendment to Lease, dated
June 23, 1997 (the "First Amendment"), with respect to Space `A' on the 25th
Floor (the "25th Floor Premises"), Space `A' on the 10th Floor (the "10th Floor
Premises") and Space `Y' on the Subbasement Floor (the "Subbasement Premises")
(the 25th Floor Premises, the 10th Floor Premises and the Subbasement Premises
collectively, the "Premises") of the building located at One Rockefeller Plaza,
New York, New York (the "Building");

            WHEREAS, John A. Levin & Co., formerly known as JALC Subsidiary
Corp. ("Guarantor"), executed a certain Guaranty, dated as of June 28, 1996,
whereby Guarantor guaranteed all of Tenant's obligations under the Lease; and

            WHEREAS, Landlord and Tenant desire to modify the Original Lease to
(i) extend the term of the Lease with respect to the 25th Floor Premises, (ii)
provide for the leasing by Tenant of certain additional space consisting of the
entire 19th Floor of the Building, (iii) terminate the Lease with respect to the
10th Floor Premises, and (iv) otherwise modify the terms and conditions of the
Original Lease, all as hereinafter set forth (the Original Lease, as modified by
this Amendment, the "Lease").

            NOW, THEREFORE, in consideration of the mutual covenants herein
contained, and other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, Landlord and Tenant agree as
follows:

            1. Capitalized Terms; Recitals. All capitalized terms used herein
and not otherwise defined in this Amendment shall have the meanings ascribed to
them in the Original Lease.

<PAGE>   51
                                       2


            2. Extension of Term; Rent. (a) The term of the Original Lease with
respect to the 25th Floor Premises is hereby extended for the period (the
"Extension Period") commencing on October 1, 2004 (the "Extension Period
Commencement Date") and ending on the last day of the calendar month in which
the day immediately preceding the 10 year anniversary of the 19th Floor Premises
Commencement Date (as hereinafter defined) occurs (the "Extended Expiration
Date"), or such earlier date upon which the term may expire or be terminated
pursuant to any of the conditions of limitation or other provisions of the Lease
or pursuant to law upon all of the terms and conditions of the Original Lease,
as modified by this Amendment. All references in the Original Lease with respect
to the 25th Floor Premises to the expiration date of "September 30, 2004" shall
be deemed to be references to the "Extended Expiration Date" and all references
to "term" or "term of this Lease" or words of similar import shall be deemed to
refer to the term of the Original Lease as extended by the Extension Period.

            (b) The fixed rent payable under the Lease for the Extension Period
with respect to the 25th Floor Premises only shall be an amount equal to
$763,560.00 per annum ($63,630.00 per month) payable at the times and in the
manner specified in the Lease for the payment of Rent.

            (c) During the Extension Period, Tenant shall pay all additional
rent payable pursuant to Article Twenty-Four of the Original Lease with respect
to the 25th Floor Premises, except that (w) the clause "110% of" in Section 24.1
of the Original Lease shall be deemed to be deleted in both places in which it
appears, (x) the clause "110% of" in Section 24.2(b) of the Original Lease shall
be deemed to be deleted in both places in which it appears, (y) the term "Base
Real Estate Taxes" shall mean the R.E. Tax Share of the Real Estate Taxes for
the Tax Year commencing on July 1,1997 and ending on June 30, 1998, and (z) the
term "Base COM" shall mean the O.E. Share of the Cost of Operation and
Maintenance for the Computation Year commencing on January 1, 1998 and ending on
December 31, 1998.

            3. Lease of 19th Floor Premises. (a) Landlord hereby leases to
Tenant, and Tenant hereby leases from Landlord, the entire 19th Floor of the
Building, designated as Space `A', and being more particularly shown on Exhibit
A attached hereto (the "19th Floor Premises"), for a term commencing on the date
of execution and delivery of this Amendment by Landlord and Tenant (the 19th
floor Premises Commencement Date"), and ending on the Extended Expiration
Date, or such earlier date upon which the term may expire or be terminated
pursuant to any of the conditions of limitation or other provisions of the Lease
or pursuant to law, upon all of the terms and conditions of the Original Lease,
as modified by this Amendment. Landlord shall not be liable for failure to
deliver possession of the 19th Floor Premises to Tenant on any specified date,
and such failure shall not impair the validity of this Amendment. Landlord shall
be

<PAGE>   52
                                       3


deemed to have delivered possession of the 19th Floor Premises to Tenant upon
the giving of notice by Landlord to Tenant stating that the 19th Floor Premises
are vacant, in the condition required under this Amendment, and available for
Tenant's occupancy. There shall be no postponement of the 19th Floor Premises
Commencement Date for (i) any delay in the delivery of possession of the 19th
Floor Premises to Tenant which results from any Tenant Delay (as hereinafter
defined) or (ii) any delay by Landlord in the performance of details of
construction, decoration and mechanical adjustments, if any, the noncompletion
of which do not materially interfere with Tenant's use of the 19th Floor
Premises, or which, in accordance with good construction practice, should be
completed after the completion of other work to be performed in the 19th Floor
Premises (collectively, "Punch List Items") relating to Landlord's 19th Floor
Work (as hereinafter defined). The provisions of this Section 3(a) are intended
to constitute "an express provision to the contrary" within the meaning of
Section 223-a of the New York Real Property Law or any successor thereto.

            (b) Effective as of the 19th Floor Premises Commencement Date,
Tenant shall lease the 19th Floor Premises upon all of the terms and conditions
of the Original Lease, except as follows:

                  (i) The fixed rent payable under the Lease shall be increased
            by an amount equal to (x) $641,840.00 per annum ($53,486.67 per
            month) for the period commencing on June 1,1998 (the "19th Floor
            Premises Rent Commencement Date") and ending on the day preceding
            the 5 year anniversary of the 19th Floor Premises Commencement Date,
            both dates inclusive, and (y) $722,070.00 per annum ($60,172.50 per
            month) for the period commencing on the 5 year anniversary of the
            19th Floor Premises Commencement Date and ending on the Extended
            Expiration Date, both dates inclusive.

                  (ii) The 19th Floor Premises shall be deemed to consist of
            16,046 rentable square feet for all purposes of the Lease.

                  (iii) (x) Landlord shall pay to Tenant, toward payment of the
            cost of the work to be performed by Tenant in connection with
            Tenant's initial occupancy of the 19th Floor Premises (the "19th
            Floor Initial Installations"), an amount ("Landlord's Contribution")
            not to exceed the difference of (A) $802,300.00 less (B) the NPV
            Differential (as hereinafter defined), provided that as of the date
            on which Landlord is required to make payment pursuant to this
            Paragraph 3(b)(iii): (i) the Lease is in full force and effect and
            (ii) no Event of Default then exists. Tenant shall pay all costs of
            the 19th Floor Initial Installations in excess of Landlord's
            Contribution. Landlord's Contribution shall be payable solely on
            account of labor directly related to the 19th Floor Initial
            Installations and materials delivered to the 19th Floor Premises in
            connection with the 19th Floor Initial

<PAGE>   53
                                       4


Installations, except that Tenant may apply up to 5% of Landlord's Contribution
to pay "soft costs" incurred in connection with the 19th Floor Initial
Installations, which shall be limited to the actual architectural, consulting
and engineering fees incurred by Tenant in connection therewith, and Tenant may
apply Landlord's Contribution towards overtime freight elevator charges incurred
by Tenant in connection with the 19th Floor Initial Installations. Tenant shall
not be entitled to receive any portion of Landlord's Contribution not actually
expended by Tenant in the performance of the 19th Floor Initial Installations in
accordance with this Paragraph 3(b)(iii) nor shall Tenant have any right to
apply any unexpended portion of Landlord's Contribution as a credit against Rent
or any other obligation of Tenant under the Lease. Following the calculation of
the NPV Differential, if it shall be determined that Landlord shall have made an
overpayment of Landlord's Contribution, Tenant shall pay to Landlord the amount
of such overpayment within 10 days after the amount due is determined. For
purposes hereof, "NPV Differential" shall mean the positive difference, if any,
of (x) the net present value to Landlord as of the date of execution and
delivery of a New Lease (as hereinafter defined) by Landlord and another tenant
(the "New Lease Execution Date") of the fixed rent payable under the Original
Lease with respect to the 10th Floor Premises for the period commencing on the
New Lease Execution Date and ending on September 30, 2004 (assuming such fixed
rent is paid annually in advance), less the cost of Landlord's Work (as defined
in the First Amendment) (assuming such cost was incurred by Landlord on the New
Lease Execution Date) and the total brokerage commissions payable by Landlord in
connection with the leasing of the 10th Floor Premises pursuant to the Original
Lease (assuming such commissions (except for the portion of the commissions
payable following the expiration of Tenant's right to terminate its leasing of
the 10th Floor Premises pursuant to the Original Lease) were paid by Landlord on
the New Lease Execution Date, and assuming the portion of the commissions
payable following the expiration of Tenant's right to terminate its leasing of
the 10th Floor Premises pursuant to the Original Lease were paid by Landlord on
the first day of the lease year in which such termination right expired), with
all present value amounts calculated using a discount rate equal to 10% per
annum, less (y) the net present value to Landlord as of the New Lease Execution
Date of the fixed rent payable under the New Lease with respect to the 10th
Floor Premises for the period commencing on the New Lease Execution Date and
ending on September 30, 2004 (assuming such fixed rent is paid annually in
advance), less the value of any free rent period (including any construction
period prior to the commencement date of the New Lease) under the New Lease
commencing on the New Lease Execution Date (assuming such free rent is credited
or applied during the applicable lease year specified in the New Lease), the
cost of Landlord's Work and any work to be performed by Landlord pursuant to the
New Lease (assuming such costs were incurred

<PAGE>   54
                                       5


by Landlord on the New Lease Execution Date), any tenant improvement
contribution to be provided by Landlord pursuant to the New Lease (assuming such
contribution was paid by Landlord on the New Lease Execution Date) and the total
brokerage commissions payable by Landlord in connection with the leasing of the
10th Floor Premises pursuant to the Original Lease and the New Lease (except for
any brokerage commission that may be payable to Landlord's Agent if an outside
broker procured the tenant under the New Lease) (assuming such commissions were
paid by Landlord on the New Lease Execution Date), with all present value
amounts calculated using a discount rate equal to 10% per annum. Attached hereto
as Exhibit C is an example of the calculation of the NPV Differential using the
above methodology which has been agreed to by Landlord and Tenant and which will
be used as the basis for the determination of the actual NPV Differential.

            (y) Landlord shall pay Landlord's Contribution to Tenant following
commencement of Tenant's business operations at the 19th Floor Premises, the
final completion of the 19th Floor Initial Installations and the execution and
delivery of a New Lease by Landlord and another tenant, within 30 days following
the submission by Tenant to Landlord of a written requisition, signed by the
chief financial officer of Tenant and accompanied by (i) copies of paid invoices
covering all of the 19th Floor Initial Installations, (ii) a written
certification from Tenant's architect stating that (A) the 19th Floor Initial
Installations described on such invoices have been completed in accordance with
the plans and specifications approved by Landlord, (B) such work has been paid
in full by Tenant, and (C) all contractors, subcontractors and materialmen have
delivered to Tenant waivers of lien with respect to such work (copies of which
shall be included with such architect's certification), (iii) proof of the
satisfactory completion of all required inspections and the issuance of any
required approvals and sign-offs by all Governmental Authorities having
jurisdiction thereover, (iv) certificates of final approval of such 19th Floor
Initial Installations required by any Governmental Authority, and shall furnish
Landlord with copies thereof, together with "as-built" plans and specifications
for such 19th Floor Initial Installations prepared on an Autocad Computer
Assisted Drafting and Design System (or such other system or medium as Landlord
may accept) using naming conventions issued by the American Institute of
Architects in June, 1990 (or such other naming convention as Landlord may
accept) and magnetic computer media of such record drawings and specifications,
translated into DXF format or another format acceptable to (v) such other
documents and information as Landlord may reasonably request. The right to
receive Landlord's Contribution is for the exclusive benefit of Tenant, and in
no event shall such right be assigned to or be enforceable by or for the benefit
of any third party, including any contractor, subcontractor,

<PAGE>   55
                                       6


materialman, laborer, architect, engineer, attorney or any other Person. For
purposes hereof, "Governmental Authority (Authorities)" shall mean the United
States of America, the City, County or State of New York or any political
subdivision, agency, department, commission, board, bureau or instrumentality of
any of the foregoing, or any landmarks preservation agency (or other entity
designated or accepted for such purpose by any Governmental Authority or
landmarks preservation agency), now existing or hereafter created, having
jurisdiction over the Building, the Land or the Center.

            (iv) Tenant shall pay to Landlord or its designee, within ten (10)
Business Days after demand, all reasonable out-of-pocket costs actually incurred
by Landlord in connection with the 19th Floor Initial Installations, including
costs incurred in connection with (x) Landlord's review of the 19th Floor
Initial Installations (including review of requests for approval thereof), and
(y) the provision of Building personnel during the performance of the 19th Floor
Initial Installations required by trade union policy or otherwise, to operate
elevators or otherwise to facilitate the 19th Floor Initial Installations.

            (v) Tenant shall pay all additional rent payable pursuant to Article
Twenty-Four of the Original Lease with respect to the 19th Floor Premises,
except that (v) the clause "110% of" in Section 24.1 of the Original Lease shall
be deemed to be deleted in both places in which it appears, (w) the clause "110%
of" in Section 24.2(b) of the Original Lease shall be deemed to be deleted in
both places in which it appears, (x) the term "Base Real Estate Taxes" shall
mean the R.E. Tax Share of the Real Estate Taxes for the Tax Year commencing on
July 1, 1997 and ending on June 30, 1998, (y) the term "Base COM" shall mean the
O.E. Share of the Cost of Operation and Maintenance for the Computation Year
commencing on January 1, 1998 and ending on December 31, 1998, and (z) Tenant's
Area shall equal 16,046 rentable square feet.

            (vi) Tenant has inspected the 19th Floor Premises and agrees (x) to
accept possession of the 19th Floor Premises in the "as is" condition existing
on the 19th Floor Premises Commencement Date, (y) that neither Landlord nor
Landlord's agents have made any representations or warranties with respect to
the 19th Floor Premises or the Building except as expressly set forth herein,
and (z) Landlord has no obligation to perform any work, supply any materials,
incur any expense or make any alterations or improvements to the 19th Floor
Premises or the Building to prepare the same for Tenant's occupancy, except for
the work set forth on Exhibit B to this Amendment ("Landlord's 19th Floor
Work"). Tenant's occupancy of any portion of the 19th Floor Premises for the
conduct of its business shall be conclusive evidence, as against

<PAGE>   56
                                       7


Tenant, that (A) Landlord has Substantially Completed Landlord's 19th Floor
Work, (B) Tenant has accepted possession of the 19th Floor Premises in their
then current condition, and (C) the 19th Floor Premises and the Building are in
a good and satisfactory condition as required by the Lease. As to Landlord's
19th Floor Work, "Substantial Completion" or "Substantially Completed" means
that such work has been completed in accordance with (i) the provisions of this
Amendment applicable thereto, (ii) the plans and specifications for such work,
and (iii) all applicable Requirements, except for Punch List Items.

            (vii) Tenant shall install, and thereafter maintain in good order
and repair, a sprinkler system and fire-alarm and life-safety system serving the
19th Floor Premises. Such installation and maintenance shall be performed by
Tenant in accordance with this Lease, the Rules and Regulations and all
Requirements. If the Fire Insurance Rating Organization or any Governmental
Authority or any of Landlord's insurers requires or recommends any modifications
or Alterations be made or any additional equipment be supplied in connection
with the sprinkler system or fire-alarm and life-safety system serving the
Building or the 19th Floor Premises by reason of Tenant's business, or the
location of the partitions, trade fixtures, or other contents of the 19th Floor
Premises, Landlord (to the extent such modifications or Alterations are
structural, affect any Building system or involve the performance of work
outside the 19th Floor Premises), or Tenant (to the extent such modifications or
Alterations are nonstructural, do not affect any Building system and do not
involve the performance of work outside the 19th Floor Premises) shall make such
modifications or Alterations, and supply such additional equipment, in either
case at Tenant's expense.

            (viii) As part of the 19th Floor Initial Installations, Tenant shall
have the right to install an auxiliary HVAC system to service the 19th Floor
Premises. Landlord shall provide Tenant with up to 3 tons of chilled water for
Tenant's autonomous HVAC system through the common cooling tower unit servicing
the Building. As part of the 19th Floor Initial Installations, Tenant shall, at
Tenant's sole cost and expense, perform all necessary work and install all
required equipment to permit Tenant to tap into Landlord's chilled water risers;
provided that Landlord shall perform the actual tap in to the Building's chilled
water risers for a one-time tap in fee of $1,500.00 payable by Tenant prior to
the performance of such tap-in. Tenant shall pay, as additional rent, an annual
sum equal to the product of (a) the charge Landlord has then established as
customary for the provision of chilled water per connected ton multiplied by (b)
the number of connected tons of chilled water Landlord is obligated to provide
to Tenant, which amount shall be payable as additional rent in equal monthly
installments in advance on the first day of each month during the Term.

<PAGE>   57
                                       8


                  (ix) The provisions of Article Five of the Original Lease
            shall be applicable to the 19th Floor Premises, except that the
            clause "four watts" in the first sentence of Section 5.1 shall be
            deemed to be deleted and the clause "six watts" inserted in place
            thereof.

                  (x) Except as provided in this Amendment, all references in
            the Original Lease to the "Premises" shall be deemed to include the
            19th Floor Premises for all purposes of the Lease.

                  (xi) The following provisions of the Original Lease shall not
            be applicable to the leasing of the 19th Floor Premises: Section
            20.2 and Articles Twenty-Seven, Thirty, Thirty-One and Thirty-Two.

            4. Termination of 10th Floor Premises. (a) Effective as of the date
(the "Termination Date") that Landlord and another tenant execute and deliver a
lease (the "New Lease") for the 10th Floor Premises, the term of the Lease with
respect to the 10th Floor Premises only shall terminate as if such date was
initially set forth in the Lease as the expiration date thereof.

            (b) On or before the Termination Date, Tenant shall vacate the 10th
Floor Premises in accordance with the Lease, remove all of Tenant's personal
property therefrom and deliver vacant possession thereof to Landlord, time being
of the essence. Any fixtures, installations or personal property remaining in
the 10th Floor Premises after the Termination Date shall be deemed abandoned by
Tenant and Landlord may take possession thereof and dispose of same, at Tenant's
sole cost and expense, in any manner Landlord determines without accountability
therefor to Tenant. Tenant acknowledges that effective upon the close of the
Termination Date the Lease with respect to the 10th Floor Premises shall have
terminated and expired and Tenant shall have abandoned and surrendered any claim
of possession to the 10th Floor Premises to Landlord.

            (c) Tenant represents and warrants that it has not assigned, pledged
or encumbered the Lease or sublet the 10th Floor Premises or done or suffered
any other action as a result of which the Lease or the 10th Floor Premises might
be subject to any lien or encumbrance. Tenant warrants that the foregoing
covenants and representations will be true and correct as of the Termination
Date, Tenant has and will have good right to surrender the 10th Floor Premises
on or before the Termination Date, and delivery of possession of the 10th Floor
Premises will be made to Landlord on or before the Termination Date free and
clear of all liens and encumbrances of any kind whatsoever.

            (d) If Tenant shall fail to surrender the 10th Floor Premises to
Landlord pursuant to this Paragraph 4 on or before the Termination Date, then
Tenant shall be deemed to be a holdover in the 10th Floor Premises and be

<PAGE>   58
                                       9


subject to all of Landlord's rights and remedies available to it as landlord
under the Lease or otherwise, at law or in equity.

            (e) With respect to the foregoing termination, Tenant shall complete
and timely submit all returns and questionnaires relating to New York City and
State real property transfer tax laws and any other applicable real property
transfer or gains tax laws (the taxes which are the subject of such laws are
hereinafter collectively "Transfer Taxes"). Tenant shall timely pay all Transfer
Taxes, if any, and shall deliver evidence, reasonably acceptable to Landlord, of
such payment simultaneously to Landlord. Tenant shall indemnify, defend (with
counsel reasonably acceptable to Landlord) and hold harmless Landlord from all
losses, liabilities, interest, judgments, suits, demands, damages, costs and
expenses (including attorneys' fees and disbursements incurred in the defense
thereof) which Landlord may incur by reason of Tenant's failure to complete and
timely submit any and all Transfer Tax returns and questionnaires and/or
Tenant's failure to timely pay any and all Transfer Taxes. The provisions of
this Paragraph 4 shall survive the expiration of the Lease.

            (f) Provided Tenant is not in default under any of the terms or
provisions of the Lease, Landlord shall, within 10 days Business Days after the
Termination Date and after delivery of possession of the 10th Floor Premises to
Landlord in the manner required by the Lease, return to Tenant the Additional
Security Deposit (as defined in the First Amendment), or the remaining portion
thereof.

            5. Modifications. The provisions of the Original Lease are hereby
amended as follows:

            (a) Article Six of the Original Lease is hereby amended by deleting
Section 6.1(e)(vii) and inserting the following in place thereof:

      "(vii) Tenant is hereby notified that the Premises are subject to the
      jurisdiction of the Landmarks Preservation Commission. In accordance with
      Sections 25-305, 25-306, 25-309 and 25-310 of the Administrative Code of
      the City of New York and the rules set forth in Title 63 of the Rules of
      the City of New York, any demolition, construction, reconstruction,
      alteration or minor work as described in such Sections and such rules may
      not be commenced within or at the Premises without the prior written
      approval of the Landmarks Preservation Commission. Tenant is notified that
      such demolition, construction, reconstruction, alteration or minor work
      includes, but is not limited to, (a) work to the exterior of the Premises
      involving windows, signs, awnings,

<PAGE>   59
                                       10


      flagpoles, banners and storefront alterations and (b) interior work to the
      Premises that (i) requires a permit from the Department of Buildings or
      (ii) changes, destroys or affects an interior architectural feature of an
      interior landmark or an exterior architectural feature of an improvement
      that is a landmark or located on a landmark site or in a historic
      district."

            (b)Section 6.1(e)(ii) of the Original Lease is hereby amended by
inserting the following at the end thereof:

      "; provided that in connection with the 19th Floor Initial Installations
      or any renovation of the 25th Floor Premises performed within 12 months
      after the date of the Second Amendment to Lease, such reasonable charges
      shall not include a Landlord supervisory fee."

            (c) Article Six of the Original Lease is hereby amended by inserting
the following clauses (viii) and (ix) after Section 6.1(e)(vii):

      "(viii) The approval of plans or specifications, or the consent by
      Landlord to the making of any alterations, changes, additions,
      improvements, repairs or replacements does not constitute Landlord's
      agreement or representation that such plans, specifications or
      alterations, changes, additions, improvements, repairs or replacements
      comply with any legal requirements, requirements of insurance bodies or
      the certificate of occupancy issued for the Building. Landlord shall have
      no liability to Tenant or any other party in connection with Landlord's
      approval of plans and specifications for any alterations, changes,
      additions, improvements, repairs or replacements, or Landlord's consent to
      Tenant's performing any alterations, changes, additions, improvements,
      repairs or replacements.

      (ix) Notwithstanding anything to the contrary contained herein, Tenant
      shall pay to Landlord or its designee, within 10 days after demand, all
      out-of-pocket costs actually incurred by Landlord in connection with any
      Alteration, including costs incurred in connection with (i) Landlord's
      review of the Alterations (including review of requests for approval
      thereof), and (ii) the provision of Building personnel during the
      performance of any Alteration required by trade union policy or otherwise,
      to operate elevators or otherwise to facilitate any Alteration. In
      addition, Tenant shall pay to Landlord or its

<PAGE>   60
                                       11


      designee, upon demand, an administrative fee with respect to the
      performance of any Alteration (other than the 19th Floor Initial
      Installations or any renovation of the 25th Floor Premises performed
      within 12 months after the date of the Second Amendment to Lease) and the
      scheduling of Building equipment, facilities and personnel in connection
      therewith which fee shall be payable as follows: 5% of the cost of
      Tenant's Alterations up to $100,000; 4% of the cost of Tenant's
      Alterations between $100,000 and $250,000; 3% of the cost of Tenant's
      Alterations between $250,000 and $500,000; and 2% of the cost of Tenant's
      Alterations in excess of $500,000."

            (d) Section 6(k) of the Original Lease is hereby deleted in its
entirety and the following inserted in place thereof:

            "Tenant, at Tenant's expense, shall obtain and keep in full force
            and effect during the term of this Lease, (1) a policy of commercial
            general liability insurance on an occurrence basis against claims
            for bodily injury, death and/or property damage occurring in or
            about the premises or the Building, under which Tenant is named as
            the insured and Landlord, Landlord's managing agent, any lessors
            under underlying leases, any holders of underlying mortgages and any
            other parties whose names shall have been furnished by Landlord to
            Tenant from time to time are named as additional insureds, which
            insurance shall provide primary coverage without contribution from
            any other insurance carried by or for the benefit of Landlord,
            Landlord's managing agent or any lessors under underlying leases or
            any holders of underlying mortgages named as additional insureds,
            and Tenant agrees to obtain blanket broad-form contractual liability
            coverage to insure its indemnity obligations set forth in Article
            Six hereof. The minimum limits of liability shall be a combined
            single limit with respect to each occurrence in an amount of not
            less than $3,000,000 per occurrence, with a $5,000,000 annual
            aggregate; provided, however, that Landlord may require Tenant to
            increase such coverage, from time to time, to that amount of
            insurance which in Landlord's reasonable judgment is then being
            customarily required by landlords for similar office space in
            first-class buildings in the City of New York. If the aggregate
            limit applying to the Premises is reduced by the payment of a claim
            or establishment of a reserve equal to or greater than 50% of the
            annual aggregate, Tenant shall immediately arrange to have the
            aggregate limit restored by

<PAGE>   61
                                       12


            endorsement to the existing policy or the purchase of an additional
            insurance policy unless, in Landlord's reasonable judgment, Tenant
            maintains sufficient excess liability insurance to satisfy the
            liability requirements of this Lease without the reinstatement of
            the aggregate limit, (2) insurance against loss or damage by fire,
            and such other risks and hazards as are insurable under then
            available standard forms of "all risk" property insurance policies
            with extended coverage, insuring Tenant's goods, furniture and
            furnishings, all fixtures removable by Tenant as provided in the
            Lease, and all of Tenant's alterations and improvements to the
            Premises, for the full insurable value thereof or replacement cost
            value thereof, having a deductible amount, if any, not exceeding
            $25,000; (3) during the performance of any alteration, until
            completion thereof, Builder's risk insurance on an "all risk" basis
            and on a completed value form including a Permission to Complete and
            Occupy endorsement, for full replacement value covering the interest
            of Landlord and Tenant (and their respective contractors and
            subcontractors), any lessor of an underlying lease and any holder of
            an underlying mortgage in all work incorporated in the Building and
            all materials and equipment in or about the premises; (4) Workers'
            Compensation Insurance, as required by law; (5) Business
            Interruption Insurance; and (6) such other insurance in such amounts
            as Landlord, any holder of an underlying mortgage and/or any lessor
            of an underlying lease may reasonably require from time to time,
            provided that in Landlord's reasonable judgment such insurance is
            then being customarily required by landlords, mortgagees or superior
            lessors for similar office space in first-class buildings in the
            City of New York.

            (ii) All insurance required to be carried by Tenant pursuant to the
            terms of this Lease shall contain a provision that (1) no act or
            omission of Tenant (other than intentional unlawful or fraudulent
            acts) shall affect or limit the obligation of the insurance company
            to pay the amount of any loss sustained, (2) the policy shall be
            noncancellable and/or no material change in coverage shall be made
            thereto unless Landlord, each lessor of an underlying lease and each
            holder of an underlying mortgage shall have received 30 days' prior
            notice of the same by certified mail, return receipt requested, (3)
            Tenant shall be solely responsible for the payment of all premiums
            under such policies and Landlord, the lessors of underlying leases
            and the holders of underlying mortgages

<PAGE>   62
                                       13


            shall have no obligation for the payment thereof, and (4) shall be
            effected under valid and enforceable policies issued by reputable
            and independent insurers permitted to do business in the State of
            New York, and rated in Best's Insurance Guide, or any successor
            thereto (or if there be none, an organization having a national
            reputation) as having a Best's Rating of "A-"and a "Financial Size
            Category" of at least "IX" or if such ratings are not then in
            effect, the equivalent thereof or such other financial rating as
            Landlord may at any time consider appropriate.

                  (iii) On or prior to the 19th Floor Premises Commencement
            Date, Tenant shall deliver to Landlord appropriate policies of
            insurance, including evidence of waivers of subrogation, required to
            be carried by each party pursuant to this Lease. Evidence of each
            renewal or replacement of a policy shall be delivered by Tenant to
            Landlord at least 10 days prior to the expiration of such policy. In
            lieu of the policies of insurance required to be delivered to
            Landlord pursuant to this section (the "Policy"), Tenant may deliver
            to Landlord a certification from Tenant's insurance company which
            shall be binding on Tenant's insurance company, and which shall
            expressly provide that such certification (1) conveys to Landlord
            and any other named insured and/or additional insureds thereunder
            (the "Insured Parties") all the rights and privileges afforded under
            the Policy as primary insurance, and (2) contains an unconditional
            obligation of the insurance company to advise all Insured Parties in
            writing by certified mail, return receipt requested, at least 30
            days in advance of any termination of or change to the Policy that
            would affect the interest of any of the Insured Parties.

                  (iv) Landlord and Tenant shall each procure an appropriate
            clause in or endorsement to any property insurance covering the
            premises, the Building and personal property, fixtures and equipment
            located therein, wherein the insurance companies shall waive
            subrogation or consent to a waiver of right of recovery, and
            Landlord and Tenant agree not to make any claim against, or seek to
            recover from, the other for any loss or damage to its property or
            the property of others resulting from fire and other hazards to the
            extent covered by such property insurance; provided, however, that
            the release, discharge, exoneration and covenant not to sue
            contained herein shall be limited by and coextensive with the

<PAGE>   63
                                       14


             terms and provisions of the waiver of subrogation or waiver of
             right of recovery. If the payment of an additional premium is
             required for the inclusion of, or consent to, a waiver of
             subrogation, each party shall advise the other, in writing, of the
             amount of any such additional premiums and the other party may pay
             such additional premium. If such other party shall not elect to pay
             such additional premium, then the first party shall not be required
             to obtain such waiver of subrogation or consent to waiver."

            (e) Section 7.2.3 of the Original Lease is hereby amended by
inserting the following sentence at the end thereof:

      "The term "Applicable Rental Rate" as used in this Article with respect to
      the 19th Floor Premises only shall mean (i) $40.00 per annum for the
      period commencing on the 19th Floor Premises Commencement Date and ending
      on the day preceding the 5 year anniversary of the 19th Floor Premises
      Commencement Date and (ii) $45.00 per annum for the period commencing on
      the 5 year anniversary of the 19th Floor Premises Commencement Date and
      ending on the Extended Expiration Date. The term "Applicable Rental Rate"
      as used in this Article with respect to the 25th Floor Premises only shall
      mean $45.00 per annum for the period commencing on the Extension Period
      Commencement Date and ending on the Extended Expiration Date."

            (f) Section 9.3 of the Original Lease is hereby deleted in its
entirety.

            (g) Article Fourteen of the Original Lease is modified by deleting
Landlord's address set forth therein and replacing such address with the
following addresses:

            "RCPI Trust, c/o Tishman Speyer Properties, L.P., 45 Rockefeller
            Plaza, New York, New York 10111, Attention: Property Manager - One
            Rockefeller Plaza, with copies to (1) Office of the Center, 45
            Rockefeller Plaza, New York, New York 10111, Attention: General
            Counsel, (2) Office of the Center, 45 Rockefeller Plaza, New York,
            New York 10111, Attention: Controller, and (3) Tishman Speyer
            Properties, L.P., 520 Madison Avenue, New York, New York 10022,
            Attention: General Counsel".

<PAGE>   64
                                       15


            (h) Article Twenty-Five of the Original Lease is amended by adding
the following Sections at the end thereof:

            "25.13. Unless Landlord shall render notice to Tenant to the
            contrary, Tishman Speyer Properties, L.P. is authorized to act as
            Landlord's agent ("Landlord's Agent") in connection with the
            performance of this Lease, and Tenant shall direct all
            correspondence and requests to, and shall be entitled to rely upon
            correspondence received from, Tishman Speyer Properties, L.P., as
            agent for Landlord in accordance with Article Fourteen. Tenant
            acknowledges that Tishman Speyer Properties, L.P. is acting solely
            as agent for Landlord in connection with the foregoing; and neither
            Tishman Speyer Properties, L.P. nor any of its direct or indirect
            partners, officers, shareholders, directors, employees, principals,
            agents or representatives shall have any liability to Tenant in
            connection with this Lease, and Tenant waives any and all claims
            against any and all of such parties arising out of, or in any way
            connected with, this Lease, the Building or the Center.

            25.14. The liability of Landlord for Landlord's obligations under
            this Lease shall be limited to Landlord's interest from time to time
            in the Land and the Building and Tenant shall not look to any other
            property or assets of Landlord or the property or assets of any of
            Landlord's Agent, any holder of an underlying mortgage and any
            lessor an underlying lease, and each of their respective direct and
            indirect partners, officers, shareholders, directors, members,
            trustees, beneficiaries, employees, principals, contractors,
            licensees, invitees, servants, agents and representatives
            (collectively, the "lndemnitees") in seeking either to enforce
            Landlord's obligations under this Lease or to satisfy a judgment for
            Landlord's failure to perform such obligations; and neither Landlord
            nor the Indemnitees shall be personally liable for the performance
            of Landlord's obligations under this Lease."

            (i) Paragraph 6 of the First Amendment is hereby deleted in its
entirety.

            6. Second Additional Security Deposit. (a) Notwithstanding the
provisions of Article Twenty-Six of the Lease or Paragraph 5 of the First
Amendment to Lease, Tenant shall deposit with Landlord upon the execution of
this Amendment, an amount equal to $675,000.00 (the "Second Additional

<PAGE>   65
                                       16


Security Deposit") in cash as security for the faithful performance and
observance by Tenant of the terms, covenants and conditions of the Lease.

            (b) In lieu of a cash deposit, Tenant may deliver the Second
Additional Security Deposit to Landlord in the form of a clean, irrevocable,
non-documentary and unconditional Letter of Credit issued by and drawable upon
any commercial bank, trust company, national banking association or savings and
loan association with offices for banking purposes in the City of New York (the
"Issuing Bank"), which has outstanding unsecured, uninsured and unguaranteed
indebtedness, or shall have issued a letter of credit or other credit facility
that constitutes the primary security for any outstanding indebtedness (which is
otherwise uninsured and unguaranteed), that is then rated, without regard to
qualification of such rating by symbols such as "+" or "-" or numerical
notation, "Aa" or better by Moody's Investors Service and "AA" or better by
Standard & Poor's Ratings Service, and has combined capital, surplus and
undivided profits of not less than $500,000,000. Such Letter of Credit shall (i)
name Landlord and its successors and/or assigns as beneficiary, (ii) be in the
amount of the Second Additional Security Deposit, (iii) have a term of not less
than one year, (iv) permit multiple drawings, (v) be fully transferable by
Landlord without the payment of any fees or charges, and (vi) otherwise be in
form and content satisfactory to Landlord; provided, however, that Landlord
shall in no event be obligated to accept a Letter of Credit for any amount less
than $25,000. If upon any transfer of the Letter of Credit, any fees or charges
shall be so imposed, then such fees or charges shall be payable solely by Tenant
and the Letter of Credit shall so specify. The Letter of Credit shall provide
that it shall be deemed automatically renewed, without amendment, for
consecutive periods of one year each thereafter during the Term, unless the
Issuing Bank sends a notice (the "Non-Renewal Notice") to Landlord by certified
mail, return receipt requested, not less than 45 days next preceding the then
expiration date of the Letter of Credit, stating that the Issuing Bank has
elected not to renew the Letter of Credit. Landlord shall have the right, upon
receipt of a Non-Renewal Notice, to draw the full amount of the Letter of
Credit, by sight draft on the Issuing Bank, and shall thereafter hold or apply
the cash proceeds of the Letter of Credit pursuant to the terms of this
Paragraph. The Issuing Bank shall agree with all drawers, endorsers and bona
fide holders that drafts drawn under and in compliance with the terms of the
Letter of Credit will be duly honored upon presentation to the Issuing Bank at
an office location in Manhattan. The Letter of Credit shall be subject in all
respects to the Uniform Customs and Practice for Documentary Credits (1993
revision), International Chamber of Commerce Publication No. 500.

            (c) If Tenant defaults in the payment or performance of any the
terms, covenants or conditions of the Lease, including the payment of Rent,
Landlord may apply or retain the whole or any part of the Second Additional
Security Deposit or may notify the Issuing Bank and thereupon receive all or a

<PAGE>   66
                                       17


portion of the Second Additional Security Deposit represented by the Letter of
Credit, and use, apply, or retain the whole or any part of such proceeds, as the
case may be, to the extent required for the payment of any fixed rent,
additional rent or any other sum as to which Tenant is in default, including (i)
any sum which Landlord may expend or may be required to expend by reason of
Tenant's default, and (ii) any damages or Deficiency (as defined in the First
Amendment) to which Landlord is entitled pursuant to the Lease or applicable
Requirements, whether such damages or Deficiency accrues before or after summary
proceedings or other reentry by Landlord. If Landlord applies or retains any
part of the Second Additional Security Deposit, Tenant, upon demand, shall
deposit with Landlord the amount so applied or retained so that Landlord shall
have the full Second Additional Security Deposit on hand at all times during the
Term. If Tenant shall fully and faithfully comply with all of the terms,
covenants and conditions of the Lease, the Second Additional Security Deposit
shall be returned to Tenant after the Expiration Date and after delivery of
possession of the Premises to Landlord in the manner required by the Lease.
Tenant expressly agrees that Tenant shall have no right to apply any portion of
the Second Additional Security Deposit against any of Tenant's obligations to
pay Rent under the Lease.

            (d) Upon a sale of the Building or the Land or a leasing of the
Building, or any financing of Landlord's interest therein, Landlord shall have
the right to transfer the cash Second Additional Security Deposit or the Letter
of Credit, as applicable, to the vendee, lessee or lender. With respect to the
Letter of Credit, within five days after notice from Landlord of such sale,
leasing or financing, Tenant, at its sole cost, shall arrange for the transfer
of the Letter of Credit to the new landlord or lender, as designated by Landlord
in the foregoing notice, or to have the Letter of Credit reissued in the name of
the new landlord or lender. Tenant shall look solely to the new landlord or
lender for the return of such cash Second Additional Security Deposit or Letter
of Credit, and the provisions of this paragraph shall apply to every transfer or
assignment made of the Second Additional Security Deposit to a new landlord.
Tenant will not assign or encumber, or attempt to assign or encumber, the cash
Second Additional Security Deposit or Letter of Credit, and neither Landlord nor
its successors or assigns shall be bound by any such actual or attempted
assignment or encumbrance.

            (e) If Tenant (i) has not previously defaulted in its obligation to
pay Rent to Landlord on a timely basis under the Lease and (ii) is not then in
default in the due keeping, observance or performance of any term or condition
of the Lease, then in accordance with the provision of this Paragraph 6(e), on
and after (A) June 1, 1999, the Second Additional Security Deposit shall be
reduced to an amount equal to $500,000.00, (B) June 1, 2000, the Second
Additional Security Deposit shall be reduced to an amount equal to $300,000.00,
and (C) June 1, 2001, the Second Additional Security Deposit shall be reduced to
an amount

<PAGE>   67
                                       18


equal to $75,000.00. If the Second Additional Security Deposit is in the form of
cash, Landlord shall, within 10 Business Days following notice by Tenant to
Landlord that Tenant is entitled to reduce the Second AdditionaI Security
Deposit pursuant to this Paragraph 6(e), deliver to Tenant the amount by which
the Second Additional Security Deposit is reduced or if the Second Additional
Security Deposit is in the form of a Letter of Credit, Tenant may deliver to
Landlord an amendment to the Letter of Credit (which amendment must be
reasonably acceptable to Landlord in all respects) reducing the amount of the
Letter of Credit by the amount of the permitted reduction, and Landlord shall
execute the amendment and such other documents as are reasonably necessary to
reduce the amount of the Letter of Credit in accordance with the terms hereof.

            7. Brokerage. (a) Each of Landlord and Tenant represents and
warrants to the other that it has not dealt with any broker in connection with
this Amendment other than Tishman Speyer Properties, L.P. ("Broker") and that,
to the best of its knowledge, no other broker negotiated this Amendment or is
entitled to any fee or commission in connection herewith. The execution and
delivery of this Amendment by each party shall be conclusive evidence that each
party has relied upon the foregoing representations and warranties.

            (b) Each of Landlord and Tenant shall indemnify, defend, protect and
hold the other party harmless from and against any and all losses, liabilities,
damages, claims, judgments, fines, suits, demands, costs, interest and expenses
of any kind or nature (including reasonable attorneys' fees and disbursements)
incurred in connection with any claim, proceeding or judgment and the defense
thereof which the indemnified party may incur by reason of any claim of or
liability to any broker, finder or like agent (other than Broker) arising out of
any dealings claimed to have occurred between the indemnifying party and the
claimant in connection with this Amendment, or the above representation being
false. The provisions of this Paragraph 7 shall survive the expiration or
earlier termination of the term of the Lease.

            8. No Modification. Except as set forth herein, nothing contained in
this Amendment shall be deemed to amend or modify in any respect the terms,
provisions, or conditions of the Original Lease and such terms, provisions, and
conditions shall remain in full force and effect as modified hereby.

            9. Representations. Tenant hereby represents and warrants to
Landlord that, as of the date hereof, (a) the Lease is in full force and effect
and has not been modified except pursuant to this Amendment; (b) to the best of
Tenant's knowledge, there are no defaults existing under the Lease; (c) to the
best of Tenant's knowledge there exist no valid abatements, causes of action,
counterclaims, disputes, defenses, offsets, credits, deductions, or claims
against the enforcement of any of the terms and conditions of the Lease; and (d)
this

<PAGE>   68
                                       19


Amendment has been duly authorized, executed and delivered by Tenant and
constitutes the legal, valid and binding obligation of Tenant.

            10. Miscellaneous.

            (a) This Amendment contains the entire understanding of the parties
with respect to the subject matter hereof.

            (b) This Amendment shall be governed by the laws of the State of New
York without giving effect to conflict of laws principles thereof.

            (c) This Amendment shall be binding upon and inure to the benefit of
Landlord and Tenant and their successors and permitted assigns.

            (d) The captions, headings, and titles in this Amendment are solely
for convenience of reference and shall not affect its interpretation. For
purposes of this Amendment, whenever the words "include", "includes", or
"including" are used, they shall be deemed to be followed by the words "without
limitation", and, whenever the circumstances or the context requires, the
singular shall be construed as the plural, the masculine shall be construed as
the feminine and/or the neuter and vice versa. This Amendment shall be
interpreted and enforced without the aid of any canon, custom or rule of law
requiring or suggesting construction against the party drafting or causing the
drafting of the provision in question.

            (e) This Amendment shall not be binding upon Landlord or Tenant
unless and until Landlord shall have delivered a fully executed counterpart of
this Amendment to Tenant.

<PAGE>   69
                                       20


            11. Reaffirmation of Guaranty. By execution of this Amendment,
Guarantor hereby confirms that its obligations under the Guaranty are hereby
ratified and shall remain and continue in full force and effect with respect to
the Lease.

            IN WITNESS WHEREOF, Landlord and Tenant have executed this Amendment
as of the day and year first above written.

                              LANDLORD:

                              RCPI TRUST
                              By:  Tishman Speyer Properties, L.P., its Agent
                              By: /s/ Philip M. Waterman
                                  -------------------------------
                                      Philip M. Waterman III

                              TENANT:

                              LEVIN MANAGEMENT CO., INC.
                              By: /s/ Jessica M. Bibliowicz
                                  -------------------------------
                                  Name: Jessica M. Bibliowicz
                                  Title: President

GUARANTOR AGREES TO BE BOUND BY
THE PROVISIONS OF PARAGRAPH 11 OF
THIS SECOND AMENDMENT TO LEASE:

JOHN A. LEVIN & CO.

By:   /s/ Jessica M. Bibliowicz
      -------------------------------
      Name: Jessica M. Bibliowicz
      Title: President

<PAGE>   70

                            THIRD AMENDMENT TO LEASE

            This THIRD AMENDMENT TO LEASE, dated as of December 31, 1998 (this
"Amendment"), between RCPI TRUST, a Delaware business trust having an office c/o
Tishman Speyer Properties, L.P., 45 Rockefeller Plaza, New York, New York 10111
("Landlord"), and LEVIN MANAGEMENT CO., INC., a Delaware corporation having an
office at One Rockefeller Plaza, New York, New York 10020 ("Tenant").

                                  WITNESSETH:

            WHEREAS, Landlord's predecessor in interest, Rockefeller Center
Properties, and Tenant's predecessor-in-interest, John A. Levin & Co., Inc.,
entered into that certain Lease, dated December 20, 1993, amended by
Supplemental Indenture, dated March 2, 1995, First Amendment to Lease, dated
June 23, 1997 (the "First Amendment") and Second Amendment to Lease, dated as of
January 22, 1998, with respect to Space 'A' on the 25th Floor (the "25th Floor
Premises"), Space 'A' on the 19th Floor (the "19th Floor Premises") and Space
'Y' on the Subbasement Floor (the "Subbasement Storage Space") (the "Building")
(the Lease as heretofore amended, is hereafter the "Original Lease");

            WHEREAS, pursuant to Paragraph (6) of the Original Lease, Landlord
has elected to terminate the Original Lease with respect to the Subbasement
Storage Space, which termination is effective as of December 31, 1998 (the
"Termination Date");

            WHEREAS, in consideration of Tenant vacating the Sub-basement
Storage Space in accordance with the provisions of the Original Lease prior to
the Termination Date, Landlord has agreed to lease to Tenant, and Tenant has
agreed to hire from Landlord, certain storage premises (the "New Storage Space")
located on the 22nd Floor of the Building, substantially as shown on Exhibit A
and designated as Space 'P', on the terms and conditions set forth herein and in
the Original Lease (the Original Lease, as modified by this Amendment, is
hereafter the "Lease").

            NOW, THEREFORE, in consideration of the mutual covenants herein
contained, and other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, Landlord and Tenant agree as
follows:

            1. Capitalized Terms; Recitals. All capitalized terms used herein
and not otherwise defined in this Amendment shall have the meanings ascribed to
them in the Lease.

            2. Modifications. Effective as of the date hereof, all references
contained in the Lease to the "Premises" shall be deemed to include the New

<PAGE>   71
                                        2


Storage Space; all references contained in the Lease to space 'Y', or to the
Subbasement Premises shall be deemed to mean the New Storage Space. All
references contained in the Supplemental Indenture to the "Additional Space"
shall be deemed to mean the New Storage Space.

            3. Brokerage. (a) Each of Landlord and Tenant represents and
warrants to the other that it has not dealt with any broker in connection with
this Amendment other than Tishman Speyer Properties, L.P. ("Landlord's Agent")
and that, to the best of its knowledge, no other broker negotiated this
Amendment and that no broker (other than Landlord's Agent) is entitled to any
fee or commission in connection herewith. The execution and delivery of this
Amendment by each party shall be conclusive evidence that each party has relied
upon the foregoing representations and warranties. Landlord shall pay Landlord's
Agent any commission due in accordance with the terms of a separate agreement.

            (b) Each of Landlord and Tenant shall indemnify, defend, protect and
hold the other party harmless from and against any and all losses, liabilities,
damages, claims, judgments, fines, suits, demands, costs, interest and expenses
of any kind or nature (including reasonable attorneys' fees and disbursements)
incurred in connection with any claim, proceeding or judgment and the defense
thereof which the indemnified party may incur by reason of any claim of or
liability to any broker, finder or like agent (other than Landlord's Agent)
arising out of any dealings claimed to have occurred between the indemnifying
party and the claimant in connection with this Amendment, or the above
representation being false. The provisions of this Paragraph 3 shall survive the
expiration or earlier termination of the term of this Amendment.

            4. No Modification. Except as set forth herein, nothing contained in
this Amendment shall be deemed to amend or modify in any respect the terms,
provisions, or conditions of the Lease and such terms, provisions, and
conditions shall remain in full force and effect as modified hereby.

            5. Construction. If there is any inconsistency between the terms of
this Amendment and the terms of the Lease, the terms of this Amendment shall be
controlling and prevail.

            6. Entire Agreement. This Amendment contains the sole and entire
understanding and agreement of the parties with respect to its entire subject
matter and all prior negotiations, discussions, representations, agreements and
understandings heretofore had among the parties with respect thereto are merged
herein.

            7. Counterparts. This Amendment may be executed in duplicate
counterparts, each of which shall be deemed an original and all of which, when
taken together, shall constitute one and the same instrument.

<PAGE>   72
                                       3


            8. Representations and Warranties, Tenant hereby represents and
warrants to Landlord that, as of the date hereof, (i) the Lease is in full force
and effect and has not been modified except pursuant to this Amendment; (ii) to
the best of Tenant's knowledge, there are no defaults existing under the Lease;
(iii) to the best of Tenant's knowledge there exist no valid abatements, causes
of action, counterclaims, disputes, defenses, offsets, credits, deductions, or
claims against the enforcement of any of the terms and conditions of the Lease;
and (iv) this Amendment has been duly authorized, executed and delivered by
Tenant and constitutes the legal, valid and binding obligation of Tenant.

            9. Miscellaneous. (a) This Amendment shall be governed by the laws
of the State of New York without giving effect to conflict of laws principles
thereof.

            (b) This Amendment shall be binding upon and inure to the benefit of
Landlord and Tenant and their successors and permitted assigns.

            (c) The captions, headings, and titles in this Amendment are solely
for convenience of reference and shall not affect its interpretation.

            (d) This Amendment shall not be binding upon Landlord or Tenant
unless and until Landlord shall have delivered a fully executed counterpart of
this Amendment to Tenant.

            IN WITNESS WHEREOF, Landlord and Tenant have executed this Amendment
as of the day and year first above written.

                              LANDLORD:

                              RCPI TRUST
                              By: Tishman Speyer Properties, L.P., its Agent


                              By: /s/ Peter A. Fair
                                 -------------------------------------------
                                    Peter Fair


                              TENANT:

                              LEVIN MANAGEMENT CO., INC.


                              By: /s/ Glenn A. Aigen
                                 -------------------------------------------
                                 Name:  Glenn A. Aigen
                                 Title: VP & CFO
<PAGE>   73

                                   EXHIBIT A

                                   FLOOR PLAN

The floor plan which follows is intended solely to identify the general location
of the New Storage Space, and should not be used for any other purpose. All
areas, dimensions and locations are approximate, and any physical conditions
indicated may not exist as shown.

<PAGE>   74

                               ROCKEFELLER PLAZA

                               [GRAPHIC OMITTED]

<PAGE>   75

                            FOURTH AMENDMENT TO LEASE

            This FOURTH AMENDMENT TO LEASE, dated as of July 18, 2000 (this
"Amendment"), between RCPI TRUST, a Delaware business trust having an office c/o
Tishman Speyer Properties, L.P., 45 Rockefeller Plaza, New York, New York 10111
("Landlord"), and LEVIN MANAGEMENT CO., INC., a Delaware corporation having an
office at One Rockefeller Plaza, New York, New York 10020 ("Tenant").

                              W I T N E S S E T H:

            WHEREAS, Landlord's predecessor in interest, Rockefeller Center
Properties, and Tenant's predecessor-in-interest, John A. Levin & Co., Inc.,
entered into that certain Lease, dated December 20, 1993, amended by
Supplemental Indenture, dated March 2, 1995, First Amendment to Lease, dated
June 23, 1997 (the "First Amendment"), Second Amendment to Lease, dated as of
January 22, 1998 (the "Second Amendment"), and Third Amendment to Lease, dated
as of December 31, 1998 (the "Third Amendment"), with respect to certain
premises (the "Original Premises") in the building (the "Building") located at
One Rockefeller Plaza, New York, New York (the Lease as heretofore amended, is
hereafter the "Original Lease");

            WHEREAS, Landlord and Tenant desire to modify the Original Lease to
provide for the leasing by Tenant of certain additional space consisting of a
portion of the 3rd floor of the Building, and otherwise modify the terms and
conditions of the Original Lease, all as hereafter set forth, (the Original
Lease, as modified by this Amendment, is hereafter the "Lease").

            NOW, THEREFORE, in consideration of the mutual covenants herein
contained, and other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, Landlord and Tenant agree as
follows:

            1. Capitalized Terms; Recitals. All capitalized terms used herein
and not otherwise defined in this Amendment shall have the meanings ascribed to
them in the Lease.

            2. Lease of 3rd Floor Premises. (a) Landlord hereby leases to
Tenant, and Tenant hereby leases from Landlord, a portion of the 3rd Floor of
the Building, designated as Space 'D', and being more particularly shown on
Exhibit A attached hereto (the "3rd Floor Premises"), for a term commencing on
the later to occur of (a) July 1, 2000 and (b) the date upon which Landlord
delivers possession of the Premises to Tenant in accordance with the terms of
this Amendment (the "3rd Floor Premises Commencement Date"), and ending on
September 30, 2004, or such earlier date upon which the term may expire or be
terminated pursuant to any of the conditions of limitation or other provisions
of the Lease or pursuant to law, upon all of the terms and conditions of the
Original Lease, as modified by this Amendment. Landlord shall not be liable for
failure to

<PAGE>   76
                                       2


deliver possession of the 3rd Floor Premises to Tenant on any specified date,
and such failure shall not impair the validity of this Amendment. Landlord shall
be deemed to have delivered possession of the 3rd Floor Premises to Tenant upon
the giving of notice by Landlord to Tenant stating that the 3rd Floor Premises
are vacant, in the condition required under this Amendment, and available for
Tenant's occupancy. The provisions of this Section 2(a) are intended to
constitute "an express provision to the contrary" within the meaning of Section
223-a of the New York Real Property Law or any successor thereto.

            (b) Effective as of the 3rd Floor Premises Commencement Date, Tenant
shall lease the 3rd Floor Premises upon all of the terms and conditions of the
Original Lease, except as follows:

                  (i) The fixed rent payable under the Lease shall be increased
            by an amount equal to $159,060.00 per annum ($13,255.00 per month)
            for the period commencing on the date which is 2 months after the
            3rd Floor Commencement Date (the "3rd Floor Premises Rent
            Commencement Date") and ending on September 30, 2004, both dates
            inclusive.

                  (ii) The 3rd Floor Premises shall be deemed to consist of
            2,651 rentable square feet for all purposes of the Lease.

                  (iii) Tenant shall pay all additional rent payable pursuant to
            the Article Twenty-Four of the Original Lease, except that with
            respect to the 3rd Floor Premises only, (v) the clause "110% of" in
            Section 24.1 of the Original Lease shall be deemed to be deleted in
            both places in which it appears, (w) the clause "110% of" in Section
            24.2(b) of the Original Lease shall be deemed to be deleted in both
            places in which it appears, (x) the term "Base Real Estate Taxes"
            shall mean the R.E. Tax Share of the Real Estate Taxes for the Tax
            Year commencing on July 1, 2000 and ending on June 30, 2001, (y) the
            term "Base COM" shall mean the O.E. Share of the Cost of Operation
            and Maintenance for the Computation Year commencing on January 1,
            2000 and ending on December 31, 2000, and (z) Tenant's Area shall
            equal 2,651 rentable square feet.

                  (iv) Tenant has inspected the 3rd Floor Premises and agrees
            (i) to accept possession of the 3rd Floor Premises in the "as is"
            condition existing on the 3rd Floor Premises Commencement Date, (ii)
            that neither Landlord nor Landlord's agents have made any
            representations or warranties with respect to the 3rd Floor Premises
            or the Building except as expressly set forth herein, and (iii)
            Landlord has no obligation to perform any work, supply any
            materials, incur any expense or make any alterations or improvements
            to the 3rd Floor Premises to prepare the 3rd Floor Premises for
            Tenant's occupancy. Tenant's occupancy of any part of the 3rd Floor
            Premises shall be conclusive evidence, as against Tenant, that (A)
            Tenant has accepted possession of the 3rd Floor Premises in their
            then current condition, and (B) the 3rd Floor Premises and the
            Building are in a
<PAGE>   77
                                        3


            good and satisfactory condition as required by this Amendment.
            Notwithstanding the foregoing, Landlord agrees to deliver the 3rd
            Floor Premises to Tenant vacant and in "broom clean" condition.

                  (v) Tenant shall maintain in good order and repair, the
            sprinkler system and fire-alarm and life-safety system serving the
            3rd Floor Premises. Such maintenance shall be performed by Tenant in
            accordance with this Lease, the rules and regulations and all
            Requirements. If the Fire Insurance Rating Organization or any
            Governmental Authority or any of Landlord's insurers requires or
            recommends any modifications or Alterations be made or any
            additional equipment be supplied in connection with the sprinkler
            system or fire-alarm and life-safety system serving the Building or
            the 3rd Floor Premises by reason of Tenant's business, or the
            location of the partitions, trade fixtures, or other contents of the
            3rd Floor Premises, Landlord (to the extent such modifications or
            Alterations are structural, affect any Building System or involve
            the performance of work outside the 3rd Floor Premises), or Tenant
            (to the extent such modifications or Alterations are nonstructural,
            do not affect any Building System and do not involve the performance
            of work outside the 3rd Floor Premises) shall make such
            modifications or Alterations, and supply such additional equipment,
            in either case at Tenant's expense. Landlord represents that, as of
            the date hereof, the sprinkler system and fire-alarm and life-safety
            system serving the 3rd Floor Premises is in working order.

                  (vi) The provisions of Article Five of the Original Lease
            shall be applicable to the 3rd Floor Premises, except that the
            clause "four watts" in the first sentence of Section 5.1 shall be
            deemed to be deleted and the clause "six watts" inserted in place
            thereof.

                  (vii) Section 6.1(e)(ii) of the Original Lease is hereby
            amended by inserting the following at the end thereof:

                        "; provided that in connection with any work to be
                  performed by Tenant in connection with Tenant's initial
                  occupancy of the 3rd Floor Premises, such reasonable charges
                  shall not include a Landlord supervisory fee."

                  (viii) Except as provided in this Amendment, all references in
            the Original Lease to the "Premises" shall be deemed to include the
            3rd Floor Premises for all purposes of the Lease. With respect to
            the 3rd Floor Premises only, all references in the Original Lease to
            "term" or "term of this Lease" or words of similar import shall be
            deemed to refer to the term of the leasing of the 3rd Floor Premises
            and all references to "termination or expiration of this Lease" or
            words of similar import shall be deemed to refer to the termination
            or expiration of the leasing of the 3rd Floor Premises.

<PAGE>   78
                                       4


                  (ix) The term "Applicable Rental Rate" as used in Section
            7.2.3 of the Original Lease with respect to the 3rd Floor Premises
            only shall mean $60.00 per annum for the period commencing on the
            3rd Floor Premises Commencement Date and ending on September 30,
            2004.

                  (x) The following provisions of the Original Lease shall not
            be applicable to the leasing of the 3rd Floor Premises: Section 20.2
            and Articles Twenty-Seven, Thirty, Thirty-One, Thirty-Two and
            Thirty-Three, Paragraph 6 of the First Amendment, Paragraph 7 of the
            First Amendment, and Paragraph 2 of the Second Amendment.

            3. Brokerage. (a) Each of Landlord and Tenant represents and
warrants to the other that it has not dealt with any broker in connection with
this Amendment other than Tishman Speyer Properties, L.P. ("TSP") and Colliers
ABR, Inc. ("Colliers") and that, to the best of its knowledge, no other broker
negotiated this Amendment or is entitled to any fee or commission in connection
herewith. Landlord shall pay Colliers and TSP any commission which may be due in
connection with this Amendment pursuant to a separate agreement. Each of
Landlord and Tenant shall indemnify, defend, protect and hold the other party
harmless from and against any and all losses, liabilities, damages, claims,
judgments, fines, suits, demands, costs, interest and expenses of any kind or
nature (including reasonable attorneys' fees and disbursements) incurred in
connection with any claim, proceeding or judgment and the defense thereof which
the indemnified party may incur by reason of any claim of or liability to any
broker, finder or like agent (other than TSP and Colliers) arising out of any
dealings claimed to have occurred between the indemnifying party and the
claimant in connection with this Amendment, or the above representation being
false. The provisions of this Paragraph 3 shall survive the expiration or
earlier termination of the term of the Lease.

            4. No Modification. Except as set forth herein, nothing contained in
this Amendment shall be deemed to amend or modify in any respect the terms,
provisions, or conditions of the Lease and such terms, provisions, and
conditions shall remain in full force and effect as modified hereby.

            5. Construction. If there is any inconsistency between the terms of
this Amendment and the terms of the Lease, the terms of this Amendment shall be
controlling and prevail.

            6. Entire Agreement. This Amendment contains the sole and entire
understanding and agreement of the parties with respect to its entire subject
matter and all prior negotiations, discussions, representations, agreements and
understandings heretofore had among the parties with respect thereto are merged
herein.

<PAGE>   79
                                        5


            7. Counterparts. This Amendment may be executed in duplicate
counterparts, each of which shall be deemed an original and all of which, when
taken together, shall constitute one and the same instrument.

            8. Representations and Warranties. Tenant hereby represents and
warrants to Landlord that, as of the date hereof, (i) the Lease is in full force
and effect and has not been modified except pursuant to this Amendment; (ii) to
the best of Tenant's knowledge, there are no defaults existing under the Lease;
(iii) to the best of Tenant's knowledge there exist no valid abatements, causes
of action, counterclaims, disputes, defenses, offsets, credits, deductions, or
claims against the enforcement of any of the terms and conditions of the Lease;
and (iv) this Amendment has been duly authorized, executed and delivered by
Tenant and constitutes the legal, valid and binding obligation of Tenant.

            9. Miscellaneous. (a) This Amendment shall be governed by the laws
of the State of New York without giving effect to conflict of laws principles
thereof.

            (b) This Amendment shall be binding upon and inure to the benefit of
Landlord and Tenant and their successors and permitted assigns.

            (c) The captions, headings, and titles in this Amendment are solely
for convenience of reference and shall not affect its interpretation.

<PAGE>   80
                                        6


            (d) This Amendment shall not be binding upon Landlord or Tenant
unless and until Landlord shall have delivered a fully executed counterpart of
this Amendment to Tenant.

            IN WITNESS WHEREOF, Landlord and Tenant have executed this Amendment
as of the day and year first above written.

                             LANDLORD:

                             RCPI TRUST
                             By: Tishman Speyer Properties L.P., its Agent


                             By: /s/ Geoffrey P. Wharton
                                ------------------------------------------
                                Geoffrey P. Wharton


                             TENANT:

                             LEVIN MANAGEMENT CO., INC.


                             By: /s/ Glenn A. Aigen
                                ------------------------------------------
                                Name:  Glenn A. Aigen
                                Title: Sr VP & CFO

<PAGE>   81

                                   EXHIBIT A

                                   FLOOR PLAN

The floor plan which follows is intended solely to identify the general location
of the 3rd Floor Premises, and should not be used for any other purpose. All
areas, dimensions and locations are approximate, and any physical conditions
indicated may not exist as shown.

<PAGE>   82

                               ROCKEFELLER PLAZA

                               [GRAPHIC OMITTED]