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                                 EXHIBIT 10.120

                      THIRD AMENDMENT TO OFFICE LEASE WITH
                       ZURICH AMERICAN INSURANCE COMPANY

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                        THIRD AMENDMENT TO OFFICE LEASE
                        -------------------------------

     THIS THIRD AMENDMENT TO OFFICE LEASE (this "Amendment") is made as of this
25th day of January, 2001, by and between WINDY POINT OF SCHAUMBURG L.L.C., a
Delaware limited liability company ("Landlord"), and ZURICH AMERICAN INSURANCE
COMPANY, a New York corporation ("Tenant").

                                    RECITALS:
                                    --------

     A. Landlord and Tenant entered into a certain Office Lease (the "Original
Lease") dated as of May 6, 2000, whereby Landlord leased to Tenant certain
premises (the "Initial Premises") in that certain 11-story office building to be
built at 1600 McConnor Parkway, Schaumburg, Illinois (the "Building").

     B. Landlord and Tenant entered into a First Amendment to Office Lease (the
"First Amendment") dated as of July 14, 2000, whereby Landlord and Tenant agreed
to amend the Original Lease to reflect a change in the site plan for the parking
areas serving the Windy Point of Schaumburg complex and to reflect Landlord's
agreement to provide a rent credit to Tenant in exchange for a corresponding
reduction of the commission due Tenant's broker.

     C. Landlord and Tenant entered into a Second Amendment to Office Lease (the
"Second Amendment") dated as of August 4, 2000, whereby Landlord and Tenant
agreed to further amend the Original Lease to acknowledge the location and
rentable area of the initial leased premises, among other things. The Original
Lease, as amended by the First Amendment and the Second Amendment, is
hereinafter referred to as the "Lease."

     D. Landlord and Tenant desire to further amend the Lease to reflect
Tenant's lease of the entire Building and to reflect certain additional parking
rights for Tenant.

     NOW, THEREFORE, for good and valuable consideration, the receipt and legal
sufficiency of which are hereby acknowledged, Landlord and Tenant hereby agree
as follows:

     1. DEFINITIONS. Each capitalized term used in this Amendment shall have the
        -----------
same meaning as is ascribed to such capitalized term in the Lease, unless
otherwise provided for herein.

     2. ADDITIONAL SPACE. Landlord leases to Tenant and Tenant leases from
        ----------------
Landlord those certain premises (the "Additional Space") consisting of the 11th
floor of the Building and containing approximately 28,973 rentable square feet.
The Additional Space is leased to Tenant subject to all of the same terms and
provisions as are contained in the Lease with respect to the Initial Premises.
Henceforth, the term "Premises" as used and defined in the Lease, as amended
hereby, shall be deemed to mean and refer to the Initial Premises and the
Additional Space (i.e., all rentable space within the Building). Landlord and
Tenant acknowledge that the Premises contains 300,034 rentable square feet. Such
area has been determined by Landlord's architect in accordance with the
standards set forth in Section 2A(v) of the Original Lease.

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         3. BASE RENT. For purposes of calculating the rate of Base Rent, Tenant
            ---------
shall be deemed to have leased the entire Building in accordance with Section
1B. Landlord and Tenant acknowledge that the Base Rent for the Premises during
the initial Term shall equal the following amounts:

<TABLE>
<CAPTION>
             Annual Rental Rate for
 Lease Year   Rentable Square Foot   Annual Base Rent   Monthly Installments
 ----------   --------------------   ----------------   --------------------
 <S>         <C>                     <C>                <C>
      1           $   16.97          $  5,091,576.96      $   424,298.08

      2               17.48             5,244,594.36          437,049.53

      3               18.00             5,400,612.00          450,051.00

      4               18.54             5,562,630.36          463,552.53

      5               19.10             5,730,649.44          477,554.12

      6               19.67             5,901,668.76          491,805.73

      7               20.26             6,078,688.80          506,557.40

      8               20.87             6,261,709.56          521,809.13

      9               21.50             6,450,731.04          537,560.92

     10               22.14             6,642,752.76          553,562.73

</TABLE>

         4. TENANT'S PROPORTIONATE SHARE. Landlord and Tenant acknowledge that
            ----------------------------
Tenant's Proportionate Share is 100%.

         5. DELETIONS. Sections 27 and 28 of the Original Lease are hereby
            ---------
deleted and of no further force or effect.

         6. PARKING.
            -------

         A. The site plan attached hereto as Exhibit A shows the current
proposed configuration of the parking areas serving the Windy Point of
Schaumburg complex and such site plan attached hereto as Exhibit A is hereby
substituted for the site plan attached to the Original Lease as Exhibit H (as
previously amended).

         B. Tenant acknowledges that if Tenant desires an addition to the
parking deck in accordance with Section 26C of the Original Lease, such addition
may not exceed one level (in addition to the other requirements set forth in
Section 26C).

                                       2

<PAGE>

     C. In addition to Tenant's Special Parking Spaces (i.e., 250 parking spaces
in the parking deck), Landlord shall furnish to Tenant 345 parking spaces
reserved for Tenant's exclusive use in the surface parking lots serving the
Windy Point of Schaumburg complex at the locations shown on Exhibit A attached
hereto ("Tenant's Surface Parking Spaces"). Tenant's use of Tenant's Surface
Parking Spaces shall be subject to the terms and conditions of Section 26D of
the Original Lease. Landlord shall mark the Tenant's Surface Parking Spaces in a
reasonable manner to indicate to third parties that such spaces are reserved for
use by Tenant, and Landlord shall use reasonable and customary efforts to
prevent unauthorized use of Tenant's Surface Parking Spaces, but Landlord shall
have no responsibility for or liability in the event of any unauthorized use of
Tenant's Surface Parking Spaces. Tenant shall use reasonable and customary
efforts to prevent its employees, agents or contractors from using, the
non-reserved parking spaces serving the Windy Point of Schaumburg complex unless
all of Tenant's Special Parking Spaces and Tenant's Surface Parking Spaces are
then occupied by Tenant, its employees, agents and contractors. If the rentable
area of the Premises is reduced for any reason (including, without limitation,
Tenant's exercise of the Contraction Option), the number of Tenant's Surface
Parking Spaces (but not Tenant's Special Parking Spaces) shall be reduced
proportionally. Furthermore, as provided in Section 26A of the Original Lease,
if any governmental authority, agency or department requires the use of any
parking areas serving the Windy Point of Schaumburg complex (including areas
containing Tenant's reserved parking spaces), Tenant shall no longer have the
right to use such areas and Landlord shall have no liability to Tenant (nor
shall Rent abate or be reduced) on account of such reduction in available
parking areas (provided Landlord shall, within a reasonable period after such
areas are no longer available, cause the parking areas serving the Windy Point
of Schaumburg complex to have a number of parking spaces equal to at least 90%
of the parking spaces depicted on Exhibit A attached hereto).

     D. Landlord acknowledges that Tenant has expressed an interest in acquiring
the right to park automobiles on the site immediately north of the Windy Point
of Schaumburg complex (the "NiGas Site"). During the first year of the Term,
Landlord shall cooperate with Tenant in attempting to acquire such right from
the owner of the NiGas Site. Neither Landlord nor Tenant shall be obligated to
proceed with any such acquisition unless and until Landlord and Tenant mutually
agree, in writing, upon the configuration and other terms of such right
(provided Tenant acknowledges that it is the parties' intention that all costs
associated with such acquisition and the construction of any improvements will
be borne by Tenant, in a manner mutually agreeable to the parties).

     7. BASE BUILDING IMPROVEMENTS.
        --------------------------

     A. Landlord agrees to construct the Building so that the size of the
Building (exterior and each floor plate) is consistent with the plans and
specifications listed on Exhibit B attached hereto (subject to changes to the
size of the Building approved by Tenant in writing, in advance [which approval
shall not be unreasonably withheld, conditioned or delayed]).

     B. At Tenant's request, Landlord has agreed to incorporate the additional
base building improvements generally described on Exhibit C attached hereto.
Tenant acknowledges that the foregoing changes and additions to the base
building improvements will increase the costs thereof as shown on Exhibit C
(collectively, the "Increased Base Building Costs") and may result in Tenant

                                       3

<PAGE>

Delays with respect to those items where, under "Construction Delays," Exhibit C
states "TBD" or "None Yet." The Increased Base Building Costs shall be paid by
Tenant as follows:

          first, the credit shown on Exhibit C shall be applied against the
     Increased Base Building Costs until such credit is exhausted;

          second, upon Tenant's written request, any portion of the Allowance
     that is not allocable to the Work (as such capitalized terms are defined in
     the Work Letter Agreement) may be used to pay for the Increased Base
     Building Costs; and

          third, Tenant shall pay to Landlord any unpaid Increased Base Building
     Costs for any item described on Exhibit C within 30 days after Landlord
     provides Tenant with a copy of the general contractor's invoice (or draw
     request) for such item.

Any Tenant Delays shall have the effect set forth in Paragraph 7 of the Work
Letter Agreement. Any additional changes to the base building work desired by
Tenant beyond those described on Exhibit C shall continue to be governed by
Paragraph 8 of the Work Letter Agreement.

     8.   BROKER. Tenant represents that except for Fifield Realty Corp. and
          ------
Julien J. Studley, Inc. (collectively, the "Brokers"), Tenant has not dealt with
any real estate broker, salesperson or finder in connection with this Amendment,
and no such person initiated or participated in the negotiation of this
Amendment. Tenant agrees to indemnify, defend and hold Landlord, its property
manager and their respective employees harmless from and against all claims,
demands, actions, liabilities, damages, costs and expenses (including reasonable
attorneys' fees) arising from either (i) a claim for a fee or commission made by
any broker, other than the Broker, claiming to have acted by or on behalf of
Tenant in connection with this Amendment, or (ii) a claim of, or right to, lien
under the statutes of Illinois relating to real estate broker liens with respect
to any such broker retained by Tenant. Landlord agrees to pay the Brokers a
commission in accordance with the agreement between Landlord and the Brokers (as
amended by the First Amendment). Landlord represents to Tenant that Landlord has
dealt only with the Brokers in connection with this Amendment and that, insofar
as Landlord knows, no other broker negotiated this Amendment or is entitled to
any commission in connection herewith. Landlord agrees to indemnify, defend and
hold Tenant harmless from and against all claims, demands, actions, liabilities,
damages, costs and expenses (including reasonable attorneys' fees) arising from
a claim for a fee or commission made by any broker, other than the Brokers,
claiming to have acted by or on behalf of Landlord in connection with this
Amendment.

     9.   BINDING EFFECT. The Lease, as amended hereby, shall continue in full
          --------------
force and effect, subject to the terms and provisions thereof and hereof. In the
event of any conflict between the terms of the Lease and the terms of this
Amendment, the terms of this Amendment shall control. This Amendment shall be
binding upon and inure to the benefit of Landlord, Tenant and their respective
successors and permitted assigns.

                                       4

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     10. LIMITATION OF LIABILITY. Any liability of Landlord under the Lease, as
         -----------------------
amended hereby, shall be limited solely to its equity interest in the Building,
and in no event shall any personal liability be asserted against Landlord in
connection with the Lease, as amended hereby, nor shall any recourse be had to
any other property or assets of Landlord. The obligations of Tenant under the
Lease, as amended hereby, do not constitute personal obligations of the
individual officers and employees of Tenant.

     IN WITNESS WHEREOF, this Amendment is executed as of the day and year
aforesaid.


LANDLORD:                                     TENANT:
--------                                      ------

WINDY POINT OF SCHAUMBURG                     ZURICH AMERICAN INSURANCE
L.L.C., a  Delaware limited                   COMPANY, a New York corporation
liability company

By: FRC WINDY POINT L.L.C., an
    Illinois limited liability company, its
    managing member                           By: /s/ Robert Windsor
                                                  ------------------------------
                                              Title: Vice President
                                                     ---------------------------

    By: /s/ Steven D. FiField
        ---------------------------
    Title: Managing Member
           ------------------------


                               MORTGAGEE'S CONSENT
                               -------------------

         The undersigned hereby consents to the foregoing Amendment, provided
that the undersigned reserves all rights granted to the undersigned under the
loan documents to review additional changes to the scope of work for the
Building.

                                        NATIONAL CITY BANK OF MICHIGAN-ILLINOIS


                                        By: /s/ [ILLEGIBLE]
                                            ------------------------------------
                                        Title: Senior Vice President
                                               ---------------------------------

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<PAGE>

                                    EXHIBIT A

         REVISED PARKING PLAN (SHOWING RESERVED SURFACE PARKING SPACES)

                            [SITE PLAN APPEARS HERE]