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                                                                  EXHIBIT 10.22
                                                                    10-K Filing

                               91 HARTWELL AVENUE
                            LEXINGTON, MASSACHUSETTS

                          LEASE DATED NOVEMBER 12, 1996


     THIS INSTRUMENT IS AN INDENTURE OF LEASE in which the Landlord and the
Tenant are the parties hereinafter named, and which relates to space in a
certain building (the "Building") known as, and with an address at, 91 Hartwell
Avenue, Lexington, Massachusetts.

     The parties to this Indenture of Lease hereby agree with each other as
follows:

                                    ARTICLE I
                                    ---------

                                 REFERENCE DATA
                                 --------------

1.1  Subjects Referred To:

     Each reference in this Lease to any of the following subjects shall be
     construed to incorporate the data stated for that subject in this Article:

     LANDLORD:                      Mortimer B. Zuckerman and Edward H.
                                    Linde, Trustees of 91 Hartwell Avenue Trust
                                    under Declaration of Trust dated September
                                    28, 1981 filed with the Middlesex South
                                    Registry District as Document No. 616455
                                    as amended by instruments dated December
                                    10, 1984 and April 17, 1991 respectively
                                    filed with said Registry District as
                                    Document Nos. 675674 and 844541 but not
                                    individually.

     LANDLORD'S ORIGINAL            c/o Boston Properties, Inc.
     ADDRESS:                       8 Arlington Street
                                    Boston, Massachusetts 02116

     LANDLORD'S CONSTRUCTION        James C. Rosenfeld or Stacey A. Baker
     REPRESENTATIVE:

     TENANT:                        RESTRAC, INC. a Delaware corporation.



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     TENANT'S ORIGINAL              3 Allied Drive
     ADDRESS:                       Dedham, Massachusetts 02026

     TENANT'S CONSTRUCTION          Martin J. Fahey
     REPRESENTATIVE:

     SPECIAL ALLOWANCE:             As defined in Section 3.1.1

     SCHEDULED TERM                 January 1, 1997.
     COMMENCEMENT DATE:

     COMMENCEMENT DATE:             As defined in Sections 2.4 and 3.2

     OUTSIDE COMPLETION DATE:       March 15, 1997.

     ORIGINAL TERM:                 Eighty-four (84) calendar months (plus the
                                    partial month, if any, immediately following
                                    the Commencement Date), unless extended
                                    or sooner terminated as provided in this
                                    Lease.

     EXTENSION OPTIONS:             Two (2) periods of three (3)  years each as
                                    provided in and on the terms set forth in
                                    Section 2.4.1 hereof.

     TERM OR LEASE TERM:            All references in this Lease to the Term or
                                    Lease Term shall mean the Original Term
                                    and if extended pursuant to Section 2.4.1,
                                    the Original Term as extended by the
                                    exercise of the applicable extension options
                                    unless otherwise specifically provided in
                                    this Lease.

     THE SITE:                      That certain parcel of land known as and
                                    numbered 91 Hartwell Avenue, Lexington,
                                    Middlesex County, Massachusetts, being more
                                    particularly described in Exhibit A attached
                                    hereto.

     THE BUILDING:                  The Building known as and numbered
                                    91 Hartwell Avenue, Lexington,

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                                    Massachusetts.  The Building is
                                    appropriately labeled on Exhibit A-1
                                    attached hereto and hereby made a part
                                    hereof.

     THE COMPLEX:                   The Building together with all surface
                                    parking areas, the Site and all improvements
                                    (including landscaping) thereon and thereto.

     TENANT'S SPACE:                (i) The entire second (2nd) floor of the
                                    Building and (ii) a portion of the first
                                    (1st) floor of the Building, all in
                                    accordance with the floor plan attached
                                    hereto as Exhibit D and incorporated herein
                                    by reference.

     NUMBER OF PARKING SPACES:      210 spaces.

     ANNUAL FIXED RENT:             (a) During the Original Term of this Lease
                                    at the following annual rates:

                                         (i) For the period beginning on the
                                         Commencement Date and continuing
                                         through the date which is six (6)
                                         months following the Commencement Date
                                         (the "Reduced Rent Period"), at the
                                         ANNUAL RATE of $1,152,139.00 (being the
                                         product of (x) $23.00 and (y) 50,093
                                         rentable square feet of the total
                                         60,093 square feet of "Rentable Floor
                                         Area of the Premises" (hereinafter
                                         defined in the Section 1.1); and

                                         (ii) For the period beginning on the
                                         day immediately following the
                                         expiration of the Reduced Rent Period
                                         and continuing through the day
                                         immediately preceding the second annual
                                         anniversary of the Commencement Date,
                                         at the ANNUAL RATE of $1,382,139.00
                                         (being the

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                                         product of (x) $23.00 and (y) the total
                                         Rentable Floor Area of the Premises);
                                         and

                                         (iii) For the period beginning on the
                                         second (2nd) annual anniversary of the
                                         Commencement Date and continuing
                                         through the day immediately preceding
                                         the fifth (5th) annual anniversary of
                                         the Commencement Date, at the ANNUAL
                                         RATE of $1,442,232.00 (being the
                                         product of (x) $24.00 and (y) the total
                                         Rentable Floor Area of the Premises);
                                         and

                                         (iv) For the period beginning on the
                                         fifth (5th) annual anniversary of the
                                         Commencement Date and continuing though
                                         the last day of the Original Term, at
                                         the ANNUAL RATE of $1,502,325.00 (being
                                         the product of (x) $25.00 and (y) the
                                         total Rentable Floor Area of the
                                         Premises).

                                    (b) During the extension option periods (if
                                    exercised), as determined pursuant to
                                    Section 2.4.1.

     OPERATING EXPENSES:            As provided in Section 2.6 hereof.

     REAL ESTATE TAXES:             As provided in Section 2.7 hereof.

     TENANT ELECTRICITY:            Initially as provided in Section 2.5 subject
                                    to adjustment as provided in Section 2.8
                                    hereof.

     ADDITIONAL RENT:               All charges and other sums payable by Tenant
                                    as set forth in this Lease, in addition to
                                    Annual Fixed Rent.

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     RENTABLE FLOOR AREA            60,093 square feet.
     OF TENANT'S SPACE
     (SOMETIMES ALSO
     CALLED RENTABLE FLOOR
     AREA OF THE PREMISES):

     TOTAL RENTABLE FLOOR           122,328 square feet.
     AREA OF THE BUILDING:

     PERMITTED USES:                General office purposes, computer software
                                    development and non retail sales, and
                                    related services, including without
                                    limitation training and customer support.

     INITIAL MINIMUM                $2,000,000.00 combined single limit
     LIMITS OF TENANT'S             on a per occurrence basis and
     COMMERCIAL GENERAL             $5,000,000.00 on an aggregate basis.
     LIABILITY INSURANCE:
     RECOGNIZED BROKERS:            Spaulding & Slye Services Limited
                                    Partnership
                                    125 High Street, 16th Floor
                                    Boston, Massachusetts 02110
                                             and
                                    Lynch Murphy Walsh & Partners
                                    Incorporated
                                    One Financial Center
                                    Boston, Massachusetts 02111

     SECURITY DEPOSIT:              $720,000.00 subject to reduction on the
                                    terms set forth in Section 8.20 hereof.


1.2  Exhibits. There are incorporated as part of this Lease:

     EXHIBIT A        Description of Site

     EXHIBIT A-1      Site Plan

     EXHIBIT B        Schedule of Tenant's Preliminary Construction Plans

     EXHIBIT C        Landlord's Services

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     EXHIBIT D        Floor Plans

     EXHIBIT E        Form of Commencement Date Agreement

     EXHIBIT F        Plan of Balance of First Floor Space

     EXHIBIT G        Broker Determination of Prevailing Market Rent

     EXHIBIT H        Form of Subordination, Non-Disturbance and Attornment 
                      Agreement with Existing Mortgagee

1.3  Table of Articles and Sections


     ARTICLE I-REFERENCE DATA

     1.1  Subjects Referred to

     1.2  Exhibits

     1.3  Table of Articles and Sections


         ARTICLE II-THE BUILDINGS, PREMISES, TERM AND RENT

     2.1  The Premises

          2.1.1 Tenant's Right of First Offer

     2.2  Rights To Use Common Facilities

          2.2.1 Tenant's Parking

     2.3  Landlord's Reservations

     2.4  Original Term

          2.4.1 Extension Options

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     2.5  Monthly Fixed Rent Payments

     2.6  Adjustment for Operating Expenses

     2.7  Adjustment for Real Estate Taxes

     2.8  Adjustment for Tenant Electricity


     ARTICLE III-CONSTRUCTION

     3.1  Tenant's Plans

          3.1.1 Special Allowance

     3.2  Landlord's and Tenant's Work; Delays

     3.3  Alterations and Additions

     3.4  General Provisions Applicable to Construction


     ARTICLE IV-LANDLORD'S COVENANTS; INTERRUPTIONS AND DELAYS

     4.1  Landlord's Covenants

          4.1.1 Services Furnished by Landlord

          4.1.2 Additional Services Available to Tenant

          4.1.3 Roof, Exterior Wall, Floor Slab and Common Facility Repairs

          4.1.4 Door Signs and Monument Sign

     4.2  Interruptions and Delays in Services and Repairs, etc.


     ARTICLE V-TENANT'S COVENANTS

     5.1  Payments

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     5.2  Repair and Yield Up

     5.3  Use

     5.4  Obstructions; Items Visible From Exterior; Rules and Regulations

     5.5  Safety Appliances; Licenses

     5.6  Assignment; Sublease

     5.7  Indemnity; Insurance

     5.8  Personal Property at Tenant's Risk

     5.9  Right of Entry

     5.10 Floor Load; Prevention of Vibration and Noise

     5.11 Personal Property Taxes

     5.12 Compliance with Laws

     5.13 Payment of Litigation Expenses


     ARTICLE VI-LANDLORD'S INSURANCE, CASUALTY AND TAKING

     6.0  Landlord's Insurance

     6.1  Fire and Casualty-Termination or Restoration; Rent Adjustment

     6.2  Uninsured Casualty

     6.3  Eminent Domain-Termination or Restoration

     6.4  Eminent Domain Damages Reserved


     ARTICLE VII-DEFAULT

     7.1  Tenant's Default

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     7.2  Landlord's Default

     ARTICLE VIII-MISCELLANEOUS PROVISIONS

     8.1  Extra Hazardous Use

     8.2  Waiver

     8.3  Cumulative Remedies

     8.4  Quiet Enjoyment

     8.5  Notice To Mortgagee and Ground Lessor

     8.6  Assignment of Rents

     8.7  Surrender

     8.8  Brokerage

     8.9  Invalidity of Particular Provisions

     8.10 Provisions Binding, Etc.

     8.11 Recording

     8.12 Notices

     8.13 When Lease Becomes Binding

     8.14 Section Headings

     8.15 Rights of Mortgagee

     8.16 Status Report and Financial Statements

     8.17 Self-Help

     8.18 Holding Over

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      8.19 Non-Subrogation
 
      8.20 Security Deposit

      8.21 Late Payment

      8.22 Volleyball Court

      8.23 Governing Law


                                   ARTICLE II
                                   ----------

                        BUILDING, PREMISES, TERM AND RENT
                        ---------------------------------

2.1   Landlord hereby demises and leases to Tenant, and Tenant hereby hires and
      accepts from Landlord, Tenant's Space in the Building excluding exterior
      faces of exterior walls, the common stairways and stairwells, elevators
      and elevator wells, fan rooms, electric and telephone closets, janitor
      closets, and pipes, ducts, conduits, wires and appurtenant fixtures
      serving exclusively, or in common, other parts of the Building, and if
      Tenant's Space includes less than the entire rentable area of any floor,
      excluding the common corridors, elevator lobbies and toilets located on
      such floor.

      Tenant's Space with such exclusions is hereinafter referred to as the
      "Premises". The term "Building" means the Building identified on the first
      page, and which is the subject of this Lease; the term "Site" means all,
      and also any part of the Land described in Exhibit A, plus any additions
      or reductions thereto resulting from the change of any abutting street
      line and all parking areas and structures. The term "Property" means the
      Building and the Site. Tenant shall have available for its employees
      twenty-four (24) hour per day card access to the Premises except in the
      case of emergencies or events beyond Landlord's reasonable control
      including, but not limited to, events constituting "Landlord's Force
      Majeure (defined in Section 3.2 hereof).

2.1.1 (A) This Section applies only to that portion of the first (1st) floor of
      the Building shown on Exhibit F as the "Offer Space". Landlord shall have
      the right, in its sole discretion and upon terms and conditions solely
      determined by it, initially to lease all or any portion of the Offer Space
      to any one or more tenants without Tenant having any right or opportunity
      to lease such space. Such leases and the terms thereof, (including, but
      not limited to, the original lease terms thereof, options to extend the
      terms thereof, rights of first offer, rights of first refusal and other
      expansion rights thereunder), any subsequent extensions of the lease term
      thereof and amendments to such leases are

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      hereinafter called the "Initial Leases" and the tenants under the Initial
      Leases are hereinafter called the "Initial Tenants". Subject to (i) the
      Initial Leases and (ii) the rights of the Initial Tenants thereunder, all
      of which rights are hereby made prior to the rights of Tenant under this
      Section 2.1.1 notwithstanding that the Initial Leases may have been
      executed subsequent to the Date of this Lease or before the Date of the
      Lease and provided that at any time any portion of the Offer Space becomes
      so available for reletting to a tenant other than an Initial Tenant (i)
      Tenant is not then in default of its obligations under this Lease, (ii)
      Tenant has not assigned this Lease nor sublet fifty percent (50%) or more
      of the Rentable Floor Area of the Premises (other than an assignment or
      subletting under Section 5.6.1 hereof) and (iii) this Lease is still in
      full force and effect, Landlord agrees not to enter into a lease or leases
      to relet the Offer Space (or such portion thereof) to a tenant other than
      an Initial Tenant without first giving to Tenant an opportunity to lease
      such space upon the terms and conditions hereinafter set forth.

      (B) When any such space becomes so available for reletting to a tenant
      other than an Initial Tenant for such space upon the foregoing conditions,
      Landlord shall notify Tenant of the availability of such space and shall
      advise Tenant of the then fair market rent and business terms reasonably
      determined by Landlord upon which Landlord is willing so to lease such
      space. If Tenant wishes to exercise Tenant's right of first offer, Tenant
      shall do so, if at all, by giving Landlord notice of Tenant's desire to
      lease the entire amount of such space so available for reletting (it being
      agreed that Tenant has no right to lease less than the entire amount of
      the space which is so available) on such terms set forth in Landlord's
      notice within sixteen (16) days after Tenant's receipt of Landlord's
      notice to Tenant of the availability of such space and of such terms. If
      Tenant shall give such notice, the same shall constitute an agreement to
      enter into an amendment to this Lease within fifteen (15) days following
      Tenant's acceptance to incorporate such space into the Premises upon the
      terms set forth in Landlord's notice. If Tenant shall not so exercise such
      right within such period or if Tenant shall timely give an acceptance to
      Landlord but shall not enter into such an amendment to this Lease within
      said fifteen (15) day period (time being of the essence in respect of such
      exercise and execution), Landlord shall be free at any time thereafter to
      enter into a lease of such space with another prospective tenant or
      tenants upon terms and conditions as determined by Landlord without having
      any further obligation to offer such space to Tenant and Tenant shall have
      no further right under this Section to such space (unless such space again
      becomes available for reletting in which case the provisions of this
      Section 2.1.1 shall again apply when such space again becomes available
      for reletting). Time is of the essence with respect to the time periods
      set forth herein.

      (C) If Tenant shall exercise any such right of first offer and if,
      thereafter, the then occupant of the premises with respect to which Tenant
      shall have so exercised such right

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      wrongfully fails to deliver possession of such premises at the time when
      its tenancy is scheduled to expire, Landlord shall use reasonable efforts
      (which shall be limited to the commencement and prosecution thereafter of
      eviction proceedings and to the payment of legal fees and other expenses
      reasonably associated with such proceedings but which shall not require
      the taking of any appeal) to evict such occupant from the applicable
      portion of the Offer Space and to deliver possession of the applicable
      portion of the Offer Space to Tenant as soon as may be practicable.
      Commencement of the term of Tenant's occupancy and lease of such
      additional space and all obligations of Tenant with respect to such Offer
      Space (including, without limitation, rental and additional rent
      obligations as to such Offer Space) shall, in the event of such holding
      over by such occupant, be deferred until possession of the additional
      space is delivered to Tenant. Notwithstanding the foregoing, Tenant may
      revoke its exercise of its right of first offer if occupancy of the
      applicable Offer Space is not delivered by Landlord within three (3)
      months after the date set for commencement in the lease amendment for such
      space (an "Exercise Revocation"). However, the failure of the then
      occupant of such premises to so vacate and/or such Exercise Revocation
      shall not constitute a default of Landlord and shall not give Tenant any
      right to terminate this Lease or to deduct from, offset against or
      withhold Annual Fixed Rent, Additional Rent or other charges due under
      this Lease (or any portions thereof).

      (D) If Tenant shall lease additional space in the Building pursuant to
      this Section 2.1.1, Tenant's parking rights under this Lease shall be
      increased on the basis of 3.5 parking spaces for each 1,000 square feet of
      rentable floor area of such additional space.

2.2   Tenant shall have, as appurtenant to the Premises, the non-exclusive right
      to use in common with others, subject to reasonable rules of general
      applicability to tenants of the Building from time to time made by
      Landlord of which Tenant is given notice (a) the common lobbies,
      corridors, stairways, elevators and loading area of the Building, and the
      pipes, ducts, conduits, wires and appurtenant meters and equipment serving
      the Premises in common with others, (b) common walkways and driveways
      necessary for access to the Building, and (c) if the Premises include less
      than the entire rentable floor area of any floor, the common toilets,
      corridors and elevator lobby of such floor.

2.2.1 In addition, Tenant shall have the right to use the Number of Parking
      Spaces (referred to in Section 1.1) of the parking area, in common with
      use by other tenants from time to time of the Complex; provided, however,
      Landlord shall not be obligated to furnish stalls or spaces in any parking
      area specifically designated for Tenant's use. Tenant covenants and agrees
      that it and all persons claiming by, through and under it, shall at all
      times abide by all reasonable rules and regulations promulgated by
      Landlord with respect to the use of the parking areas on the Site. The
      parking privileges granted herein are non- transferrable except to a
      permitted assignee or subtenant as provided in Section 5.6

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      through Section 5.6.6. Further, Landlord assumes no responsibility
      whatsoever for loss or damage due to fire, theft or otherwise to any
      automobile(s) parked on the Site or to any personal property therein,
      however caused, and Tenant covenants and agrees, upon request from
      Landlord from time to time, to notify its officers, employees, agents and
      invitees of such limitation of liability. Tenant acknowledges and agrees
      that a license only is hereby granted, and no bailment is intended or
      shall be created.

2.3   Landlord reserves the right from time to time, without unreasonable
      interference with Tenant's use and upon reasonable notice and at agreed
      times unless otherwise required by emergency: (a) to install, use,
      maintain, repair, replace and relocate for service to the Premises and
      other parts of the Building, or either, pipes, ducts, conduits, wires and
      appurtenant fixtures, wherever located in the Premises or Building, and
      (b) to alter or relocate any other common facility, provided that
      substitutions are substantially equivalent or better. Installations,
      replacements and relocations referred to in clause (a) above shall be
      located so far as practicable in the central core area of the Building,
      above ceiling surfaces, below floor surfaces or within perimeter walls of
      the Premises.

2.4   Tenant shall have and hold the Premises for a period commencing on (the
      "Commencement Date") the earlier of (a) that date on which the Premises
      are ready for occupancy as in Section 3.2 provided, or (b) that date on
      which Tenant commences occupancy of any portion of the Premises for the
      Permitted Uses, and continuing for the Term unless sooner terminated as
      provided in Article VI or Article VII or unless extended as provided in
      Section 2.4.1; provided, that for purposes of this Lease, the Commencement
      Date shall not be deemed to occur prior to January 1, 1997, unless Tenant
      elects, in its sole discretion, to occupy the Premises (or portion
      thereof) prior to such date.

      As soon as may be convenient after the date has been determined on which
      the Term commences as aforesaid, Landlord and Tenant agree to join with
      each other in the execution of a written Declaration, in the form of
      Exhibit E, in which the date on which the Term commences as aforesaid and
      the Term of this Lease shall be stated. If Tenant shall fail to execute
      such Declaration, the Commencement Date and Lease Term shall be as
      reasonably determined by Landlord in accordance with the terms of this
      Lease.

2.4.1 (A) Provided that at the time of exercise of the then applicable option to
      extend and at the commencement date of the then applicable extension
      option period (i) there exists no Event of Default (defined in Section
      7.1), (ii) this Lease is still in full force and effect, and (iii) Tenant
      has neither assigned this Lease nor sublet more than fifty percent (50%)
      of the Rentable Floor Area of the Premises in the aggregate (except for an
      assignment or subletting permitted under Section 5.6.1 hereof), Tenant
      shall have the right to extend the Term hereof upon all the same terms,
      conditions, covenants and agreements herein

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      contained (except for the Annual Fixed Rent which shall be adjusted during
      the option periods as hereinbelow set forth) for two (2) successive
      periods of three (3) years each as hereinafter set forth. Each option
      period is sometimes herein referred to as an "Extended Term".

      (B)(i) If Tenant desires to exercise the then applicable option to extend
      the Term, then Tenant shall give notice to Landlord, not earlier than
      fifteen (15) months nor later than nine (9) months prior to the expiration
      of the Term as it may have been previously extended hereunder of Tenant's
      request for Landlord's quotation of a proposed annual fixed rent for the
      then applicable Extended Term. If at the expiration of thirty (30) days
      after the date when Landlord receives Tenant's written request as
      aforesaid (the "Negotiation Period"), Landlord and Tenant have not reached
      agreement on a determination of an annual fixed rent for the then
      applicable Extended Term and executed a written instrument extending the
      Term of this Lease pursuant to such agreement, then Tenant shall have the
      right, for thirty (30) days following the expiration of the Negotiation
      Period, to make a request to Landlord for a broker determination (the
      "Broker Determination") of the Prevailing Market Rent (as defined in
      Exhibit G) for the applicable Extended Term, which Broker Determination
      shall be made in the manner set forth in Exhibit G.

      (B) (ii) If Tenant timely shall have requested the Broker Determination,
      then in order to exercise its right to extend the Term of this Lease for
      the then applicable Extended Term, Tenant, within fifteen (15) days after
      receipt of the Broker Determination, shall give written notice to Landlord
      of Tenant's exercise of its right to extend the Lease Term for the then
      applicable Extended Term pursuant to this subsection 2.4.1(B)(ii), in
      which case the Annual Fixed Rent for the applicable Extended Term shall be
      the greater of (a) ninety-five percent (95%) of the Prevailing Market Rent
      as determined by the Broker Determination or (b) an annual rate equal to
      the product of $22.80 and the Rentable Floor Area of the Premises. Upon
      the giving of notice by Tenant within said fifteen (15) day period as
      provided in this subsection (B)(ii) then this Lease and Lease Term hereof
      shall be extended for an additional term of three (3) years upon all of
      the same terms, conditions, covenants and agreements contained in this
      Lease except that the Annual Fixed Rent for the applicable Extended Term
      shall be the rent determined as described in this subparagraph.

      (C) Upon the giving of notice by Tenant to Landlord exercising Tenant's
      then applicable option to extend the Lease Term in accordance with the
      provisions of either subsection (B)(i) or (B)(ii) above, this Lease and
      the Lease Term hereof shall be extended, for the applicable Extended Term,
      without the necessity for the execution of any additional documents,
      except that Landlord and Tenant agree to enter into an instrument in
      writing setting forth the Annual Fixed Rent for the then applicable

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      Extended Term but the failure to so enter into such a written instrument
      shall not negate the exercise of the applicable option to extend.
      Notwithstanding anything herein contained to the contrary, in no event
      shall Tenant have the right to exercise more than one extension option at
      a time and, further, Tenant shall not have the right to exercise its
      second extension option unless it has duly exercised its first extension
      option and in no event shall the Lease Term hereof be extended for more
      than six (6) years after the expiration of the Original Term hereof.

2.5   Tenant agrees to pay to Landlord, or as directed by Landlord, at
      Landlord's Original Address specified in Section 1.1 hereof, or at such
      other place as Landlord shall from time to time designate by notice, (1)
      (a) on the Commencement Date (defined in Section 1.1 hereof) and
      thereafter monthly, in advance, on the first day of each and every
      calendar month during the Original Term, a sum equal to one twelfth
      (1/12th) of the applicable Annual Fixed Rent (sometimes hereinafter
      referred to as "fixed rent") and (1) (b) on the Commencement Date and
      thereafter monthly, in advance, on the first day of each and every
      calendar month during the Original Term, a sum equal to one twelfth
      (1/12th) of $0.85 per annum for each square foot of Rentable Floor Area of
      Tenant's Space for tenant electricity subject to escalation as provided in
      Section 2.8 and (2) on the first day of each and every calendar month
      during each extension option period (if exercised), a sum equal to (a) one
      twelfth (1/12th) of the applicable annual fixed rent as determined in
      Section 2.4.1 for the applicable extension option period plus (b) then
      applicable monthly electricity charges (subject to escalation for
      electricity as provided in Section 2.8 hereof). Until notice of some other
      designation is given, fixed rent and all other charges for which provision
      is herein made shall be paid by remittance to or for the order of Boston
      Properties, Inc., Agents, at 8 Arlington Street, Boston, Massachusetts
      02116, and all remittances received by Boston Properties, Inc., as Agents
      as aforesaid, or by any subsequently designated recipient, shall be
      treated as payment to Landlord.

      Annual Fixed Rent for any partial month shall be paid by Tenant to
      Landlord at such rate on a pro rata basis, and, if the Commencement Date
      is a day other than the first day of a calendar month, the first payment
      which Tenant shall make to Landlord shall be a payment equal to a
      proportionate part of such monthly Annual Fixed Rent for the partial month
      from the Commencement Date to the first day of the succeeding calendar
      month.

      Other charges payable by Tenant on a monthly basis, as hereinafter
      provided, likewise shall be prorated, and the first payment on account
      thereof shall be determined in similar fashion but shall commence on the
      Commencement Date; and other provisions of this Lease calling for monthly
      payments shall be read as incorporating this undertaking by Tenant.


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<PAGE>   16

      The Annual Fixed Rent and all other charges for which provision is herein
      made shall be paid by Tenant to Landlord, without offset, deduction or
      abatement except as otherwise specifically set forth in this Lease.

2.6   "Landlord's Operating Expenses" means the cost of operation of the
      Building and the Site which shall exclude costs of special services
      rendered to tenants (including Tenant) for which a separate charge is
      made, but shall include, without limitation, the following: premiums for
      insurance carried with respect to the Building and the Site (including,
      without limitation, liability insurance, insurance against loss in case of
      fire or casualty and insurance of monthly installments of fixed rent and
      any Additional Rent which may be due under this Lease and other leases of
      space in the Building for not more than 12 months in the case of both
      fixed rent and Additional Rent and if there be any first mortgage of the
      Property, including such insurance as may be required by the holder of
      such first mortgage); compensation and all fringe benefits, workmen's
      compensation insurance premiums and payroll taxes paid to, for or with
      respect to all persons engaged in the operating, maintaining or cleaning
      of the Building or Site, water, sewer, electric, gas, oil and telephone
      charges (excluding utility charges separately chargeable to tenants for
      additional or special services); cost of building and cleaning supplies
      and equipment; cost of maintenance, cleaning and repairs (other than
      repairs not properly chargeable against income or reimbursed from
      contractors under guarantees); cost of snow removal and care of
      landscaping; payments under service contracts with independent
      contractors; management fees at reasonable rates consistent with the type
      of occupancy and the service rendered; and all other reasonable and
      necessary expenses paid in connection with the operation, cleaning and
      maintenance of the Building and the Site and properly chargeable against
      income, provided, however, there shall be included (a) depreciation for
      capital expenditures made by Landlord (i) to reduce operating expenses if
      Landlord shall have reasonably determined that the annual reduction in
      operating expenses shall exceed depreciation therefor or (ii) to comply
      with applicable laws, rules, regulations, requirements, statutes,
      ordinances, by-laws and court decisions of all public authorities which
      are now or hereafter in force (herein collectively called "Legal
      Requirements"); plus (b) in the case of both (i) and (ii) an interest
      factor, reasonably determined by Landlord, as being the interest rate then
      charged for long term mortgages by institutional lenders on like
      properties within the locality in which the Building is located;
      depreciation in the case of both (i) and (ii) shall be determined by
      dividing the original cost of such capital expenditure by the number of
      years of useful life of the capital item acquired and the useful life
      shall be reasonably determined by Landlord in accordance with generally
      accepted accounting principles and practices in effect at the time of
      acquisition of the capital item.

      "Operating Expenses Allocable to the Premises" shall mean the same
      proportion of Landlord's Operating Expenses for and pertaining to the
      Building and the Site as the

                                      -16-
 
<PAGE>   17

      Rentable Floor Area of Tenant's Space bears to the Total Rentable Floor
      Area of the Building.

      "Base Operating Expenses" shall mean Landlord's Operating Expenses for
      calendar year 1997 (that is, the period beginning January 1, 1997 and
      ending December 31, 1997).

      "Base Operating Expenses Allocable to the Premises" shall mean the same
      proportion of Base Operating Expenses as the Rentable Floor Area of
      Tenant's Space bears to the Total Rentable Floor Area of the Building.

      If with respect to any calendar year falling within the Term after the
      period for which Base Operating Expenses are calculated, or fraction of a
      calendar year falling within the Term at the beginning or end thereof, the
      Operating Expenses Allocable to the Premises for a full calendar year
      exceed Base Operating Expenses Allocable to the Premises or for any such
      fraction of a calendar year exceed the corresponding fraction of Base
      Operating Expenses Allocable to the Premises (such amount being
      hereinafter sometimes referred to as the "Operating Cost Excess") then
      Tenant shall pay to Landlord, as Additional Rent, the amount of such
      excess. Such payments shall be made at the times and in the manner
      hereinafter provided in this Section 2.6. (The Base Operating Expenses
      Allocable to the Premises do not include the $0.85 for tenant electricity
      to be paid by Tenant together with Annual Fixed Rent and for which
      provision is made in Section 2.5 hereof, separate provision being made in
      Section 2.8 of this Lease for Tenant's share of increases in electricity
      costs.)

      Not later than ninety (90) days after the end of the first calendar year
      or fraction thereof ending December 31 and of each succeeding calendar
      year during the Term or fraction thereof at the end of the Term, Landlord
      shall render Tenant a statement in reasonable detail and according to
      usual accounting practices certified by a representative of Landlord,
      showing for the preceding calendar year or fraction thereof, as the case
      may be, Base Operating Expenses, Landlord's Operating Expenses and
      Operating Expenses Allocable to the Premises. Said statement to be
      rendered to Tenant shall also show for the preceding year or fraction
      thereof as the case may be the amounts of operating expenses already paid
      by Tenant as Additional Rent on account of the operating expenses and the
      amount of the Operating Cost Excess remaining due from, or overpaid by,
      Tenant for the year or other period covered by the statement. Within
      thirty (30) days after the date of delivery of such statement, Tenant
      shall pay to Landlord the balance of the amounts, if any, required to be
      paid pursuant to the above provisions of this Section 2.6 with respect to
      the preceding year or fraction thereof, or Landlord shall credit any
      amounts overpaid by Tenant against (i) monthly installments of fixed rent
      next thereafter coming due or (ii) any sums then due from Tenant to
      Landlord under this Lease (or

                                      -17-
 
<PAGE>   18

      refund such portion of the overpayment as aforesaid if the Term has ended
      and Tenant has no further obligation to Landlord).

      In addition, Tenant shall make payments monthly on account of Tenant's
      share of increases in operating expenses anticipated for the then current
      year at the time and in the fashion herein provided for the payment of
      fixed rent. The amount to be paid to Landlord shall be an amount
      reasonably estimated annually by Landlord to be sufficient to cover, in
      the aggregate, a sum equal to the Operating Cost Excess for each calendar
      year during the Term.

      Notwithstanding the foregoing provisions, no decrease in Landlord's
      Operating Expenses shall result in a reduction of the amount otherwise
      payable by Tenant if and to the extent said decrease is attributable to
      vacancies in the Building rather than to any other causes.

      Tenant shall have the right to audit the applicable records of Landlord to
      confirm as the case may be (i) that the Operating Expenses billed to
      Tenant are proper and conform to this Section 2.6. Such right shall be
      exercisable by Tenant within ninety (90) days following Tenant's receipt
      of Landlord's annual statement of such charges. Landlord shall cooperate
      with Tenant in providing Tenant reasonable access to Landlord's books and
      records during normal business hours to enable Tenant to audit Landlord's
      books and records as they relate to any costs and expenses passed through
      to Tenant pursuant to this Section 2.6. If the audit discloses any
      overpayment on the part of Tenant, then Tenant shall be entitled to a
      refund of any such amount unless within fifteen (15) days after receipt of
      written notice from Tenant accompanied by the audit results, Landlord
      challenges the methodology or results of the audit in which case no
      adjustment shall be made until final resolution. No audit or challenge
      shall postpone, defer or reduce any requisite payments by Tenant.

2.7   If with respect to any full Tax Year or fraction of a Tax Year falling
      within the Term after the period for which Base Taxes are calculated,
      Landlord's Tax Expenses Allocable to the Premises (as hereinafter defined)
      for a full Tax Year exceed Base Taxes Allocable to the Premises or for any
      such fraction of a Tax Year exceed the corresponding fraction of Base
      Taxes Allocable to the Premises (such amount being hereinafter sometimes
      referred to as the "Tax Excess") then, on or before the thirtieth (30th)
      day following receipt by Tenant of the certified statement referred to
      below in this Section 2.7, Tenant shall pay to Landlord, as Additional
      Rent, the amount of the Tax Excess. In addition, payments by Tenant on
      account of the Tax Excess anticipated for the then current year shall be
      made monthly at the time and in the fashion herein provided for the
      payment of fixed rent. The amount so to be paid to Landlord shall be an
      amount reasonably estimated by Landlord to be sufficient to provide
      Landlord, in the aggregate, a sum equal to the Tax Excess at least ten
      (10) days before the day on which such payments by Landlord would become

                                      -18-
 
<PAGE>   19

      delinquent. Not later than ninety (90) days after Landlord's Tax Expenses
      Allocable to the Premises are determined for the first such Tax Year or
      fraction thereof and for each succeeding Tax Year or fraction thereof
      during the Term, Landlord shall render Tenant a statement in reasonable
      detail certified by a representative of Landlord showing for the preceding
      year or fraction thereof, as the case may be, real estate taxes on the
      Building and the Site and abatements and refunds of any taxes and
      assessments. Expenditures for legal fees and for other expenses incurred
      in obtaining the tax refund or abatement may be charged against the tax
      refund or abatement before the adjustments are made for the Tax Year.

      To the extent that real estate taxes shall be payable to the taxing
      authority in installments with respect to periods less than a Tax Year,
      the foregoing statement shall be rendered and payments made on account of
      such installments. Notwithstanding the foregoing provisions, no decrease
      in Landlord's Tax Expenses with respect to any Tax Year shall result in a
      reduction of the amount otherwise payable by Tenant if and to the extent
      said decrease is attributable to vacancies in the Building or partial
      completion of the Building rather than to any other causes.

      Terms used herein are defined as follows:

           (i)    "Tax Year" means the twelve-month period beginning July 1 each
                  year during the Term or if the appropriate governmental tax
                  fiscal period shall begin on any date other than July 1, such
                  other date.

           (ii)   "Landlord's Tax Expenses Allocable to the Premises" shall mean
                  the same proportion of Landlord's Tax Expenses for and
                  pertaining to the Building and the Site as the Rentable Floor
                  Area of Tenant's Space bears to 95% of the Total Rentable
                  Floor Area of the Building.

           (iii)  "Landlord's Tax Expenses" with respect to any Tax Year means
                  the aggregate real estate taxes on the Building and Site with
                  respect to that Tax Year, reduced by any abatement receipts
                  with respect to that Tax Year.

           (iv)   "Base Taxes" means Landlord's Tax Expenses (hereinbefore
                  defined) for fiscal tax year 1997 (that is, the period
                  beginning July 1, 1996 and ending June 30, 1997).

           (v)    "Base Taxes Allocable to the Premises" means the same
                  proportion of Base Taxes as the Rentable Floor Area of
                  Tenant's Space bears to 95% of the Total Rentable Floor Area
                  of the Building.

                                      -19-
 


<PAGE>   20

           (vi)   "Real estate taxes" means all taxes and special assessments of
                  every kind and nature assessed by any governmental authority
                  on the Building or Site which the Landlord shall become
                  obligated to pay because of or in connection with the
                  ownership, leasing and operation of the Site, the Building and
                  the Property (including, without limitation, if applicable the
                  excise prescribed by Mass Gen Laws Chapter 121A, Section 10
                  and amounts in excess thereof paid to the Town of Lexington
                  pursuant to agreement between Landlord and the Town) and
                  reasonable expenses of any proceedings for abatement of taxes.
                  The amount of special taxes or special assessments to be
                  included shall be limited to the amount of the minimum
                  permissible installment (plus any interest, other than penalty
                  interest, payable thereon) of such special tax or special
                  assessment required to be paid during the year in respect of
                  which such taxes are being determined. There shall be excluded
                  from such taxes all income, estate, succession, inheritance
                  and transfer taxes; provided, however, that if at any time
                  during the Term the present system of ad valorem taxation of
                  real property shall be changed so that in lieu of, or in
                  addition to, the whole or any part of the ad valorem tax on
                  real property there shall be assessed on Landlord a capital
                  levy or other tax on the gross rents received with respect to
                  the Site or Building or Property, or a federal, state, county,
                  municipal, or other local income, franchise, excise or similar
                  tax, assessment, levy or charge (distinct from any now in
                  effect in the jurisdiction in which the Property is located)
                  measured by or based, in whole or in part, upon any such gross
                  rents, then any and all of such taxes, assessments, levies or
                  charges, to the extent so measured or based, shall be deemed
                  to be included within the term "real estate taxes" but only to
                  the extent that the same would be payable if the Site and
                  Building were the only property of Landlord.

      Tenant shall have the right to audit the applicable records of Landlord to
      confirm as the case may be (i) that the real estate taxes billed to Tenant
      are proper and conform to this Section 2.7. Such right shall be
      exercisable by Tenant within ninety (90) days following Tenant's receipt
      of Landlord's annual statement of such charges. Landlord shall cooperate
      with Tenant in providing Tenant reasonable access to Landlord's books and
      records during normal business hours to enable Tenant to audit Landlord's
      books and records as they relate to any costs and expenses passed through
      to Tenant pursuant to this Section 2.7. If the audit discloses any
      overpayment on the part of Tenant, then Tenant shall be entitled to a
      refund of any such amount unless within fifteen (15) days after receipt of
      written notice from Tenant accompanied by the audit results, Landlord
      challenges the methodology or results of the audit in which case no
      adjustment shall be

                                      -20-
 
<PAGE>   21

      made until final resolution. No audit or challenge shall postpone, defer
      or reduce any requisite payments by Tenant.

2.8   If with respect to any calendar year falling within the Term or fraction
      of a calendar year falling within the Term at the beginning or end
      thereof, the cost of furnishing electricity to the Building and the Site,
      including common areas and facilities and space occupied by tenants, (but
      expressly excluding utility charges separately chargeable to tenants for
      additional or special services) for a full calendar year exceeds $0.85 per
      square foot of Rentable Floor Area of the Building, or for any such
      fraction of a calendar year exceeds the corresponding fraction of $0.85
      per square foot of Rentable Floor Area of the Building, then Tenant shall
      pay to Landlord, as Additional Rent, on or before the thirtieth (30th) day
      following receipt by Tenant of the statement referred to below in this
      Section 2.8, its proportionate share of the amount of such excess (i.e.
      the same proportion of such excess as the Rentable Floor Area of Tenant's
      Space bears to the Total Rentable Floor Area of the Building). Payments by
      Tenant on account of such excess shall be made monthly at the time and in
      the fashion herein provided for the payment of Annual Fixed Rent. The
      amount so to be paid to Landlord shall be an amount from time to time
      reasonably estimated by Landlord to be sufficient to cover, in the
      aggregate, a sum equal to such excess for each calendar year during the
      Term. If for any calendar year falling within the Term such cost is less
      than $0.85 per square foot of Rentable Floor Area of the Building (or if
      for any fraction of a calendar year falling within the Term at the
      beginning or end thereof, such cost is less than the corresponding
      fraction of $0.85 per square foot of Rentable Floor Area of the Building)
      an appropriate reduction shall be made in the amount payable by Tenant.

      Not later than ninety (90) days after the end of the first calendar year
      or fraction thereof ending December 31 and of each succeeding calendar
      year during the Term or fraction thereof at the end of the Term, Landlord
      shall render Tenant a reasonably detailed accounting certified by a
      representative of Landlord showing for the preceding calendar year, or
      fraction thereof, as the case may be, the costs of furnishing electricity
      to the Building. Said statement to be rendered to Tenant also shall show
      for the preceding year or fraction thereof, as the case may be, the amount
      already paid by Tenant on account of electricity, and the amount remaining
      due from, or overpaid by, Tenant for the year or other period covered by
      the statement. Within thirty (30) days after the date of the delivery of
      such statement, Tenant shall pay to Landlord the balance of the amounts,
      if any required to be paid pursuant to the above provisions of this
      Section 2.8 with respect to the preceding year, or fraction thereof, or
      Landlord shall credit any amounts due from it to Tenant pursuant to the
      above provisions of this Section 2.8 against monthly installments of
      Annual Fixed Rent or Additional Rent next thereafter coming due unless the
      Lease Term has expired and Tenant has no other or further obligations to
      Landlord, in which case Landlord shall promptly refund such amount to
      Tenant.

                                      -21-
<PAGE>   22

      If at any time during the Term, or any extended term, Tenant reasonably
      concludes that the amount payable by Tenant hereunder for electricity for
      lights and power to the Premises is materially less than results from the
      above calculation, Tenant shall have the right to first give written
      notice to Landlord setting forth in reasonable detail Tenant's reasons
      therefor and Landlord and Tenant shall, in good faith, attempt to resolve
      such situation to their reasonable and mutual satisfaction. If such a
      resolution shall not result, then Tenant shall have the right, at its sole
      cost and expense, to arrange for a study or audit of electrical usage at
      the Complex by an electrical engineer acceptable to both Landlord and
      Tenant, in the respective exercise of their reasonable judgement. If the
      results of such study or inspection establish that the amount payment by
      Tenant is greater or lesser than the sum of the cost of electricity for
      lights and power to the Premises, the amount payable under this Section
      2.8 shall be appropriately adjusted; provided, however, that Landlord
      shall have the right to review the methodology used and results obtained
      by such engineer and to challenge the results of such study or audit.


                                   ARTICLE III
                                   -----------

                                  CONSTRUCTION
                                  ------------

3.1   Attached hereto as Exhibit B is a schedule of the preliminary construction
      plans showing in general terms the layout of and anticipated construction
      in the Premises ("Tenant's Preliminary Construction Plans"). The final
      plans for the construction of the initial improvements to the Premises are
      in the process of being completed (the "Final Tenant Construction Plans").
      Both Landlord and Tenant acting reasonably and promptly shall have the
      right to approve the Final Tenant Construction Plans. In addition, Tenant
      shall have the right to review all construction cost estimates and to
      require competitive bidding if Tenant determines, in its discretion, that
      such estimates are unreasonable. Landlord shall perform the work shown on
      the Final Tenant Construction Plans as so approved by Landlord and Tenant.
      In no event, however, shall Landlord's monetary obligation exceed the
      amount of the special allowance set forth in Section 3.1.1 hereof.
      However, except as otherwise provided in Exhibit B, Landlord shall have no
      responsibility for the installation or connection of Tenant's computer,
      telephone or other communications equipment, systems or wiring.

3.1.1 Landlord shall provide Tenant with a special allowance in the amount of
      $781,209.00 to be applied towards (i) the cost of the architectural plans
      and space planning respecting the work shown on the Final Tenant
      Construction Plans; (ii) the cost of demolition as shall be necessary or
      is associated with preparing the Premises for the construction of the work
      shown on the Final Tenant Construction Plans and (iii) the cost of the
      work to be performed by Landlord shown on the Final Tenant Construction
      Plans. Tenant shall pay

                                      -22-
 
<PAGE>   23



      Landlord, as Additional Rent, any cost of performing the work or items
      described in items (i) through (iii) above (collectively sometimes called
      the "Space Planning, Demolition And Construction Work") in excess of said
      special allowance within thirty (30) days after being billed therefor. In
      the event that the cost of the Space Planning, Demolition And Construction
      Work is less than the special allowance, such excess shall be applied
      against Annual Fixed Rent or Additional Rent next due pursuant to this
      Lease.

3.2   Landlord agrees to use due diligence to complete the work described in
      Section 3.1 on or before the Scheduled Term Commencement Date. Landlord
      shall not be required to install any improvements which are not in
      conformity with the plans and specifications for the Building or which are
      not approved by Landlord's architect. In case of delays due to
      governmental regulation, unusual scarcity of or inability to obtain labor
      or materials, labor difficulties, casualty or other causes reasonably
      beyond Landlord's control (collectively, "Landlord's Force Majeure"), the
      Scheduled Term Commencement Date shall be extended for the period of such
      delays. The Premises shall be deemed ready for occupancy on the date on
      which the work described in Section 3.1, together with common facilities
      for access and service to the Premises, has been substantially completed
      except for (i) items of work and adjustment of equipment and fixtures
      which can be completed after occupancy thereof has been taken without
      causing substantial interference with Tenant's use of the Premises (i.e.
      so-called "punch list" items) and (ii) items of work for which there is a
      long lead time in obtaining the materials therefor or which are specially
      or specifically manufactured, produced or milled for the work in or to the
      Premises and require additional time for receipt or installation, the
      absence of which do not substantially interfere with Tenant's occupancy of
      the Premises ("long lead" items). Landlord shall complete as soon as
      conditions practically permit the punch list items and the long lead items
      and Tenant shall not use the Premises in such manner as will increase the
      cost of completion. Landlord shall permit Tenant access for installing
      furnishings in portions of the Premises when it can be done without
      material interference with remaining work.

      If, however, Landlord shall have failed to substantially complete the work
      to be performed by Landlord in accordance with Section 3.1 (excluding
      punch list items and long lead items) on or before the Outside Completion
      Date (which date shall be extended automatically for such periods of time
      as Landlord is prevented from proceeding with or completing the same by
      reason of Landlord's Force Majeure or any act or failure to act of Tenant
      which interferes with Landlord's construction of the Premises, without
      limiting Landlord's other rights on account thereof), Tenant shall have
      the right to terminate this Lease by giving notice to Landlord of Tenant's
      desire to do so within the time period from the Outside Completion Date
      (as so extended) until the date which is thirty (30) days subsequent to
      the Outside Completion Date (as so extended); and, upon the giving of such
      notice, the Term of this Lease shall cease and come to an end without
      further

                                      -23-
 
<PAGE>   24

      liability or obligation on the part of either party unless, within thirty
      (30) days after Landlord's receipt of Tenant's notice Landlord
      substantially completes the work to be performed by Landlord under Section
      3.1 (except for punch list items and long lead items) and such right of
      termination shall be Tenant's sole and exclusive remedy at law or in
      equity or otherwise for Landlord's failure so to complete such work within
      such time.

      Tenant agrees that no delay by it, or anyone employed by it, in performing
      work to prepare the Premises for occupancy (including, without limitation,
      the work in installing telephones and other communications equipment or
      systems) shall delay commencement of the Term or the obligation to pay
      rent, regardless of the reason for such delay or whether or not it is
      within the control of Tenant or any such employee.

3.3   This Section 3.3 shall apply before and during the Term. Tenant shall not
      make alterations and additions to Tenant's space except in accordance with
      plans and specifications therefor first approved by Landlord, which
      approval shall not be unreasonably withheld. Landlord shall not be deemed
      unreasonable for withholding approval of any alterations or additions
      which (a) involve or might affect any structural or exterior element of
      the Building, any area or element outside of the Premises, or any facility
      serving any area of the Building outside of the Premises, or (b) will
      delay completion of the Premises or Building, or (c) will require unusual
      expense to readapt the Premises to normal office use on Lease termination
      or increase the cost of construction or of insurance or taxes on the
      Building or of the services called for by Section 4.1 unless Tenant first
      gives assurance acceptable to Landlord for payment of such increased cost
      and that such readaptation will be made prior to such termination without
      expense to Landlord. Landlord's review and approval of any such plans and
      specifications and consent to perform work described therein shall not be
      deemed an agreement by Landlord that such plans, specifications and work
      conform with applicable Legal Requirements and requirements of insurers of
      the Building (herein called "Insurance Requirements") nor deemed a waiver
      of Tenant's obligations under this Lease with respect to applicable Legal
      Requirements and Insurance Requirements nor impose any liability or
      obligation upon Landlord with respect to the completeness, design
      sufficiency or compliance of such plans, specifications and work with
      applicable Legal Requirements and Insurance Requirements. In the case of
      all alterations, additions and improvements, Tenant shall deliver
      reasonably detailed plans and specifications to Landlord at the time
      Tenant seeks Landlord's approval. Landlord may elect to require Tenant (i)
      to remove any alterations, additions, improvements upon lease expiration
      or termination by stating such election in Landlord's approval if given
      pursuant to the foregoing and/or (ii) to remove upon lease expiration or
      termination any of the tenant improvements not shown on the Tenant's
      Preliminary Construction Plans (attached hereto as Exhibit B) but which
      are shown the "Final Tenant Construction Plans" (approved pursuant to
      Section 3.1 hereof) by stating such election at the time of Landlord's and
      Tenant's approval of the Final Tenant's

                                      -24-
 
<PAGE>   25

      Construction Plans pursuant to Section 3.1 hereof. Any items or matters so
      to be removed shall be specified by Landlord in reasonable detail. Unless
      specified for removal as aforesaid, all alterations, additions and
      improvements (and the initial improvements) shall be part of the Building
      unless specifically otherwise agreed upon in writing by Landlord and
      Tenant. All of Tenant's alterations and additions and installation of
      furnishings shall be coordinated with any work being performed by Landlord
      and in such manner as to maintain harmonious labor relations and not to
      damage the Building or Site or interfere with construction or operation of
      the Building and other improvements to the Site and, except for
      installation of furnishings, shall be performed by Landlord's general
      contractor or by contractors or workmen first approved by Landlord. Except
      for work by Landlord's general contractor, Tenant, before its work is
      started, shall secure all licenses and permits necessary therefor; deliver
      to Landlord a statement of the names of all its contractors and
      subcontractors and the estimated cost of all labor and material to be
      furnished by them and security satisfactory to Landlord protecting
      Landlord against liens arising out of the furnishing of such labor and
      material; and cause each contractor to carry workmen's compensation
      insurance in statutory amounts covering all the contractor's and
      subcontractor's employees and commercial general liability insurance or
      comprehensive general liability insurance with a broad form comprehensive
      liability endorsement with such limits as Landlord may reasonably require,
      but in no event less than $1,000,000.00 combined single limit per
      occurrence on a per location basis (all such insurance to be written in
      companies approved by Landlord and naming and insuring Landlord and
      Landlord's managing agent as additional insureds and insuring Tenant as
      well as the contractors), and to deliver to Landlord certificates of all
      such insurance. Tenant agrees to pay promptly when due the entire cost of
      any work done on the Premises by Tenant, its agents, employees, or
      independent contractors, and not to cause or permit any liens for labor or
      materials performed or furnished in connection therewith to attach to the
      Premises or the Building or the Site and immediately to discharge any such
      liens which may so attach. Tenant shall pay, as Additional Rent, 100% of
      any real estate taxes on the Complex which shall, at any time after
      commencement of the Term, result from any alteration, addition or
      improvement to the Premises made by Tenant.

3.4   All construction work required or permitted by this Lease shall be done in
      a good and workmanlike manner and in compliance with all applicable Legal
      Requirements and Insurance Requirements now or hereafter in force. Each
      party may inspect the work of the other at reasonable times and shall
      promptly give notice of observed defects. Each party authorizes the other
      to rely in connection with design and construction upon approval and other
      actions on the party's behalf by any Construction Representative of the
      party named in Article I or any person hereafter designated in
      substitution or addition by notice to the party relying. Except for items
      identified by Tenant by written notice to Landlord given within thirty
      (30) days after Tenant takes occupancy of the Premises, and as otherwise
      provided in Article IV, the work required of Landlord pursuant to this

                                      -25-
 
<PAGE>   26

      Article III shall be deemed approved by Tenant when Tenant commences
      occupancy of the Premises for the Permitted Uses, except for items which
      are then uncompleted (including punch list items and long lead items) and
      as to which Tenant shall have given notice to Landlord prior to such date.


                                   ARTICLE IV
                                   ----------

                 LANDLORD'S COVENANTS; INTERRUPTIONS AND DELAYS
                 ----------------------------------------------

4.1   Landlord covenants:

4.1.1 To furnish services, utilities, facilities and supplies set forth in
      Exhibit C equal to those customarily provided by landlords in high quality
      buildings in the Boston West Suburban Market subject to escalation
      reimbursement in accordance with Section 2.6. Landlord's said services
      include periodic, unscheduled and random visits to the Site by a roving
      independent contracted for third party security company during the hours
      of 6:00 p.m. and 6:00 a.m. excluding Saturdays, Sundays and holidays. Such
      visits to the Site are limited to checking the burglar alarm panel in the
      Building and the perimeter of the Building and parking lot on the Site.
      Tenant acknowledges that Landlord does not provide any security services
      other than contracting with the third party security company as stated
      above and for the card access systems referred to in Exhibit E. Tenant
      further acknowledges that Landlord does not assume or undertake any
      obligation to provide security beyond the security specifically listed
      above and in Exhibit E or to increase the level of said security for which
      provisions is made above and in Exhibit E.

4.1.2 To furnish, at Tenant's expense, reasonable additional Building operation
      services which are usual and customary in similar office buildings in the
      Boston West Suburban Market upon reasonable advance request of Tenant at
      reasonable and equitable rates from time to time established by Landlord.

4.1.3 Subject to the escalation provisions of Section 2.6 and except as
      otherwise provided in Article VI, (i) to make in timely fashion (subject
      to "Landlord's Force Majeure" as defined in Section 3.2) such repairs to
      the roof, exterior walls, floor slabs and common areas and facilities as
      may be necessary to keep them in serviceable condition and (ii) to
      maintain the Building (exclusive of Tenant's responsibilities under this
      Lease) in a first class manner comparable to the maintenance of similar
      properties in the Boston West Suburban Market including providing and
      performing the services for which Landlord is entitled to escalation
      reimbursement pursuant to Section 2.6 hereof.


                                      -26-
 
<PAGE>   27

4.1.4 To provide and install, at Landlord's expense, letters or numerals on the
      entrance doors to the Premises to identify Tenant's official name and
      Building address; all such letters and numerals shall be in the building
      standard graphics and no others shall be used or permitted on the
      Premises. In addition, there exists on the Site a monument type sign
      identifying the address of the Property. Landlord shall include Tenant's
      name ("RESTRAC, INC.") on said sign in addition to such other tenants and
      other parties as Landlord shall determine but said sign need not identify
      any subtenants or assignees of Tenant.

4.2   Landlord shall not be liable to Tenant for any compensation or reduction
      of rent by reason of inconvenience or annoyance or for loss of business
      arising from the necessity of Landlord or its agents entering the Premises
      for any of the purposes in this Lease authorized, or for repairing the
      Premises or any portion of the Building however the necessity may occur.
      In case Landlord is prevented or delayed from making any repairs,
      alterations or improvements, or furnishing any services or performing any
      other covenant or duty to be performed on Landlord's part, by reason of
      any cause reasonably beyond Landlord's control, including without
      limitation the causes set forth in Section 3.2 hereof as being reasonably
      beyond Landlord's control, Landlord shall not be liable to Tenant
      therefor, nor, except as expressly otherwise provided in Article VI, shall
      Tenant be entitled to any abatement or reduction of rent by reason
      thereof, nor shall the same give rise to a claim in Tenant's favor that
      such failure constitutes actual or constructive, total or partial,
      eviction from the Premises.

      Landlord reserves the right to stop any service or utility system, when
      necessary by reason of accident or emergency, or until necessary repairs
      have been completed; provided, however, that in each instance of stoppage,
      Landlord shall exercise reasonable diligence to eliminate the cause
      thereof. Except in case of emergency repairs and when required by the
      nature of the emergency, Landlord will give Tenant reasonable advance
      notice of any contemplated stoppage and will use reasonable efforts to
      avoid unnecessary inconvenience to Tenant by reason thereof.


                                    ARTICLE V
                                    ---------

                               TENANT'S COVENANTS
                               ------------------

      Tenant covenants during the term and such further time as Tenant occupies
      any part of the Premises:


                                      -27-
 
<PAGE>   28

5.1   To pay when due all fixed rent and Additional Rent and all charges for
      utility services rendered to the Premises (except as otherwise provided in
      Exhibit C) and, further, as Additional Rent, all charges for additional
      services rendered pursuant to Section 4.1.2.

5.2   Except as otherwise provided in Article VI and Section 4.1.3, to keep the
      Premises in good order, repair and condition, reasonable wear and tear
      only excepted, and all glass in windows and doors of the Premises whole
      and in good condition with glass of the same type and quality as that
      injured or broken, damage by fire or taking under the power of eminent
      domain only excepted, and at the expiration or termination of this Lease
      peaceably to yield up the Premises all construction, work, improvements,
      and all alterations and additions thereto in good order, repair and
      condition, reasonable wear and tear only excepted, first removing all
      goods and effects of Tenant and (i) to the extent specified by Landlord by
      notice to Tenant given at least ten (10) days before such expiration or
      termination, the wiring for Tenant's computer, telephone and other
      communication systems and equipment and (ii) to the extent specified in
      Landlord's notice of removal given pursuant to Section 3.3, all
      alterations, additions, improvements and initial improvements. Tenant
      shall repair any damage caused by such removal and shall restore the
      Premises and leave them clean and neat. Tenant shall not permit or commit
      any waste, and Tenant shall be responsible for the cost of repairs which
      may be made necessary by reason of damage to common areas in the Building
      or to the Site caused by Tenant, Tenant's independent contractors,
      Tenant's employees or Tenant's invitees.

5.3   Continuously from the commencement of the Term, to use and occupy the
      Premises for the Permitted Uses only, and not to injure or deface the
      Premises, Building, the Site or any other part of the Complex nor to
      permit in the Premises or on the Site any auction sale, vending machine,
      (except as set forth below) or inflammable fluids or chemicals, or
      nuisance, or the emission from the Premises of any objectionable noise or
      odor, nor to use or devote the Premises or any part thereof for any
      purpose other than the Permitted Uses, nor for any use thereof which is
      inconsistent with maintaining the Building as a first class office
      building in the quality of its maintenance, use and occupancy, or which is
      improper, offensive, contrary to law or ordinance or liable to render
      necessary any alteration or addition to the Building. Notwithstanding the
      foregoing respecting vending machines, Tenant may, at its sole cost,
      expense and risk, keep a reasonable number of vending machines in the
      Premises dispensing non-alcoholic beverages, candy, other food products
      and sundries, Tenant covenanting and agreeing that Tenant shall be solely
      responsible for compliance with applicable laws, by-laws, rules and
      regulations, for obtaining all permits, licenses and approvals therefor
      and for maintaining such permits, licenses and approvals in full force and
      effect. Further, (i) Tenant shall not, nor shall Tenant permit its
      employees, invitees, agents, independent contractors, contractors,
      assignees or subtenants to, keep, maintain, store or dispose of (into the
      sewage or waste

                                      -28-
 

<PAGE>   29


      disposal system or otherwise) or engage in any activity which might
      produce or generate any substance which is or may hereafter be classified
      as a hazardous material, waste or substance (collectively "Hazardous
      Materials"), under federal, state or local laws, rules and regulations,
      including, without limitation, 42 U.S.C. Section 6901 et seq., 42 U.S.C.
      Section 9601 et seq., 42 U.S.C. Section 2601 et seq., 49 U.S.C. Section
      1802 et seq. and Massachusetts General Laws, Chapter 21E and the rules and
      regulations promulgated under any of the foregoing, as such laws, rules
      and regulations may be amended from time to time (collectively "Hazardous
      Materials Laws"), (ii) Tenant shall immediately notify Landlord of any
      incident in, on or about the Premises, the Building or the Site that would
      require the filing of a notice under any Hazardous Materials Laws, (iii)
      Tenant shall comply and shall cause its employees, invitees, agents,
      independent contractors, contractors, assignees and subtenants to comply
      with each of the foregoing and (iv) Landlord shall have the right to make
      such inspections (including testing) as Landlord shall elect from time to
      time to determine that Tenant is complying with the foregoing.

5.4   Not to obstruct in any manner any portion of the Building not hereby
      leased or any portion thereof or of the Site used by Tenant in common with
      others; not without prior consent of Landlord to permit the painting or
      placing of any signs, curtains, blinds, shades, awnings, aerials or
      flagpoles, or the like, visible from outside the Premises; and to comply
      with all reasonable rules and regulations now or hereafter made by
      Landlord, of which Tenant has been given notice, for the care and use of
      the Building and Site and their facilities and approaches; Landlord shall
      not be liable to Tenant for the failure of other occupants of the Building
      to conform to such rules and regulations.

5.5   To keep the Premises equipped with all safety appliances required by any
      public authority because of any use made by Tenant other than the
      Permitted Uses and to procure all licenses and permits so required because
      of such use and, if requested by Landlord, to do any work so required
      because of such use, it being understood that the foregoing provisions
      shall not be construed to broaden in any way Tenant's Permitted Uses.

5.6   Except as otherwise expressly provided herein, Tenant covenants and agrees
      that it shall not assign, mortgage, pledge, hypothecate or otherwise
      transfer this Lease and/or Tenant's interest in this Lease or sublet
      (which term, without limitation, shall include granting of concessions,
      licenses or the like) the whole or any part of the Premises. Any
      assignment, mortgage, pledge, hypothecation, transfer or subletting not
      expressly permitted in or consented to by Landlord under Sections
      5.6.1-5.6.6 shall be void, ab initio; shall be of no force and effect; and
      shall confer no rights on or in favor of third parties. In addition,
      Landlord shall be entitled to seek specific performance of or other
      equitable relief with respect to the provisions hereof.


                                      -29-
<PAGE>   30

5.6.1 Notwithstanding the provisions of Section 5.6 above and the provisions of
      Section 5.6.2, 5.6.3 and 5.6.5 below, Tenant shall have the right to
      assign this Lease or to sublet the Premises (in whole or in part) to any
      parent or subsidiary corporation of Tenant or to any corporation into
      which Tenant may be converted or with which it may merge, provided that
      the entity to which this Lease is so assigned or which so sublets the
      Premises has the financial capability, credit worthiness and liquidity to
      perform the obligations of the Tenant under this Lease as and when
      required under this Lease. For all purposes of this Section 5.6.1, as long
      as Tenant remains liable for all payments due under this Lease, Tenant's
      financial capability, credit worthiness and liquidity shall be sufficient
      with respect to the assignee or subtenant. Any such assignment or
      subletting shall be subject to the provisions of Section 5.6.4 and Section
      5.6.6 below.

5.6.2 Notwithstanding the provisions of Section 5.6 above, in the event Tenant
      desires to assign this Lease or to sublet the Premises in whole or in
      part, Tenant shall notify Landlord thereof in writing and Landlord shall
      have the right at its sole option, to be exercised within thirty (30) days
      after receipt of Tenant's notice, to:

           (i)    In the case of a proposed assignment of the Lease or
                  subletting of the entire Premises, Landlord may, at its sole
                  option, elect to terminate this Lease as of a date specified
                  in a notice to Tenant, which date shall not be earlier than
                  sixty (60) days nor later than one hundred twenty (120) days
                  after Landlord's notice to Tenant; provided, however, that
                  upon the termination date as set forth in Landlord's notice,
                  all obligations relating to the period after such termination
                  date (but not those relating to the period before such
                  termination date) shall cease and promptly upon being billed
                  therefor by Landlord, Tenant shall make final payment of all
                  rent and Additional Rent due from Tenant through the
                  termination date.

           (ii)   In the case of a proposed subleasing of less than the entire
                  Premises, Landlord may, at its sole option, elect to terminate
                  this Lease as to such portion of the Premises proposed to be
                  sublet (herein called the "Terminated Portion of the
                  Premises") as of a date which shall be not earlier than sixty
                  (60) days nor later than one hundred twenty (120) days after
                  Landlord's notice to Tenant; provided, however, that upon the
                  termination date as set forth in Landlord's notice, all of
                  Landlord's and Tenant's obligations as to the Terminated
                  Portion of the Premises relating to the period after such
                  termination date (but not those relating to the period before
                  such termination date) shall cease and promptly upon being
                  billed therefor by Landlord, Tenant shall make final payment
                  of all rent and Additional Rent due from Tenant respecting the
                  Terminated Portion of the Premises through the termination
                  date and provided, further, that this

                                      -30-
 
<PAGE>   31



                  Lease shall remain in full force and effect as to the
                  remainder of the Premises, except that from and after the
                  termination date the Rentable Floor Area of the Premises shall
                  be reduced to the rentable floor area of the remainder of the
                  Premises and the definition of Rentable Floor Area of the
                  Premises shall be so amended and after such termination all
                  references in this Lease to the "Premises" or the "Rentable
                  Floor Area of the Premises" shall be deemed to be references
                  to the remainder of the Premises, and provided further that
                  Landlord shall have the right to make such alterations and
                  improvements as may be required to separately demise the
                  Terminated Portion of the Premises. In addition, from and
                  after the effective date of any such termination, Annual Fixed
                  Rent shall be at the rate set forth in Section 1.1 but shall
                  be calculated using the rentable floor area of the remainder
                  of the Premises and Tenant's payments for operating costs,
                  real estate taxes and electricity shall be calculated on the
                  same basis set forth in this Lease using the rentable floor
                  area of the remainder of the Premises.

           (iii)  In the event that Landlord shall not exercise its termination
                  rights as aforesaid, or shall fail to give any or timely
                  notice under subsection (i) or subsection (ii) immediately
                  above, the provisions of Sections 5.6.3-5.6.6 shall be
                  applicable. This Section 5.6.2 shall not be applicable to an
                  assignment or sublease pursuant to Section 5.6.1.

5.6.3 Notwithstanding the provisions of Section 5.6 above, BUT subject to the
      provisions of this Section 5.6.3 and the provisions of Sections 5.6.4,
      5.6.5 and 5.6.6 below, in the event that Landlord shall not have exercised
      the termination right as set forth in Section 5.6.2 or shall have failed
      to give any or timely notice under Section 5.6.2, then for a period of one
      hundred twenty (120) days (i) after the receipt of Tenant's notice
      referred to in Section 5.6.2, or (ii) after the expiration of the thirty
      (30) day period referred to in Section 5.6.2 in the event Landlord shall
      not give any or timely notice under section 5.6.2, as the case may be,
      Tenant shall have the right to assign this Lease or sublet the whole or
      part of the Premises in accordance with Tenant's notice to Landlord given
      as provided in Section 5.6.4 provided that, in each instance, Tenant first
      obtains the express prior written consent of Landlord, which consent shall
      not be unreasonably withheld or delayed. Landlord shall not be deemed to
      be unreasonably withholding its consent to such a proposed assignment or
      subleasing if:

           (a)    the proposed assignee or subtenant is not of a character
                  consistent with the operation of a first class office building
                  (by way of example Landlord shall not be deemed to be
                  unreasonably withholding its consent to an assignment or
                  subleasing to any governmental agency), or

                                      -31-
 
<PAGE>   32

           (b)    the proposed assignee or subtenant is not of good character
                  and reputation, or

           (c)    the proposed assignee or subtenant does not possess adequate
                  financial capability and liquidity to perform the Tenant
                  obligations as and when due or required, or

           (d)    the assignee or subtenant proposes to use the Premises (or
                  part thereof) for a purpose other than the purpose for which
                  the Premises may be used as stated in Section 1.1 hereof, or

           (e)    the character of the business to be conducted or the proposed
                  use of the Premises by the proposed subtenant or assignee
                  shall (i) be likely to materially increase Landlord's
                  Operating Expenses beyond that which Landlord now incurs for
                  use by Tenant; (ii) be likely to materially increase the
                  burden on elevators or other Building systems or equipment
                  over the burden prior to such proposed subletting or
                  assignment; or (iii) violate or be likely to violate any
                  provisions or restrictions contained herein relating to the
                  use or occupancy of the Premises, or

           (f)    there shall be existing an Event of Default (defined in
                  Section 7.1).

5.6.4 Tenant shall give Landlord notice of any proposed sublease or assignment,
      and said notice shall specify the provisions of the proposed assignment or
      subletting, including (a) the name and address of the proposed assignee or
      subtenant, (b) in the case of a proposed assignment or subletting pursuant
      to Section 5.6.2, such information as to the proposed assignee's or
      proposed subtenant's net worth and financial capability and standing as
      may reasonably be required for Landlord to make the determination referred
      to in Section 5.6.3 above (provided, however, that Landlord shall hold
      such information confidential having the right to release same to its
      officers, accountants, attorneys and mortgage lenders on a confidential
      basis), (c) all of the terms and provisions upon which the proposed
      assignment or subletting is to be made, (d) in the case of a proposed
      assignment or subletting pursuant to Section 5.6.2, all other information
      necessary to make the determination referred to in Section 5.6.3 above and
      (e) in the case of a proposed assignment or subletting pursuant to Section
      5.6.1 above, such information as may be reasonably required by Landlord to
      determine that such proposed assignment or subletting complies with the
      requirements of said Section 5.6.1.

      If Landlord shall consent to the proposed assignment or subletting, as the
      case may be, then, in such event, Tenant may thereafter sublease or assign
      pursuant to Tenant's notice, as given hereunder; provided, however, that
      if such assignment or sublease shall not be

                                      -32-
 
<PAGE>   33

      executed and delivered to Landlord within one hundred and twenty (120)
      days after the date of Landlord's consent, the consent shall be deemed
      null and void and the provisions of Section 5.6.2 shall be applicable.

5.6.5 In addition, in the case of any assignment or subleasing as to which
      Landlord may consent (other than an assignment or subletting permitted
      under Section 5.6.1 hereof) such consent shall be upon the express and
      further condition, covenant and agreement, and Tenant hereby covenants and
      agrees that, in addition to the Annual Fixed Rent, Additional Rent and
      other charges to be paid pursuant to this Lease, fifty percent (50%) of
      the "Assignment/Sublease Profits" (hereinafter defined), if any, shall be
      paid to Landlord.

      The "Assignment/Sublease Profits" shall be the excess, if any, of (a) the
      "Assignment/Sublease Net Revenues" as hereinafter defined over (b) the
      Annual Fixed Rent and Additional Rent and other charges provided in this
      Lease prorated in the case of a partial subletting. The
      "Assignment/Sublease Net Revenues" shall be the fixed rent, Additional
      Rent and all other charges and sums payable for lease of the Premises
      either initially or over the term of the sublease or assignment PLUS all
      other profits and increases to be derived by Tenant as a result of such
      subletting or assignment, less the reasonable costs of Tenant incurred in
      such subleasing or assignment (the definition of which shall include but
      not necessarily be limited to rent concessions, brokerage commissions and
      alteration allowances) amortized over the term of the sublease or
      assignment.

      All payments of the Assignment/Sublease Profits due Landlord shall be made
      within ten (10) days of receipt of same by Tenant.

5.6.6 (A) It shall be a condition of the validity of any assignment or
      subletting of right under Section 5.6.1 above, or consented to under
      Section 5.6.3 above, that the assignee or sublessee agrees directly with
      Landlord, in form reasonably satisfactory to Landlord, to be bound by all
      the obligations of the Tenant hereunder, including, without limitation,
      the obligation to pay the rent and other amounts provided for under this
      Lease (but in the case of a partial subletting pursuant to Section 5.6.1,
      such subtenant shall agree on a pro rata basis to be so bound) including
      the provisions of Sections 5.6 through 5.6.6 hereof, but such assignment
      or subletting shall not relieve the Tenant named herein of any of the
      obligations of the Tenant hereunder, Tenant shall remain fully and
      primarily liable therefor and the liability of Tenant and such assignee
      (or subtenant, as the case may be) shall be joint and several. Further,
      and notwithstanding the foregoing, the provisions hereof shall not
      constitute a recognition of the assignment or the assignee thereunder or
      the sublease or the subtenant thereunder, as the case may be, and at
      Landlord's option, upon the termination of the Lease, the assignment or
      sublease shall be terminated.


                                      -33-

<PAGE>   34

      (B) As Additional Rent, Tenant shall reimburse Landlord promptly for
      reasonable out of pocket legal and other expenses incurred by Landlord in
      connection with any request by Tenant for consent to assignment or
      subletting.

      (C) If this Lease be assigned, or if the Premises or any part thereof be
      sublet or occupied by anyone other than Tenant, Landlord may upon prior
      notice to Tenant, at any time and from time to time, collect rent and
      other charges from the assignee, sublessee or occupant and apply the net
      amount collected to the rent and other charges herein reserved, but no
      such assignment, subletting, occupancy or collection shall be deemed a
      waiver of this covenant, or a waiver of the provisions of Sections 5.6
      through 5.6.6 hereof, or the acceptance of the assignee, sublessee or
      occupant as a tenant or a release of Tenant from the further performance
      by Tenant of covenants on the part of Tenant herein contained, the Tenant
      herein named to remain primarily liable under this Lease.

      (D) The consent by Landlord to an assignment or subletting under any of
      the provisions of Sections 5.6.1 or 5.6.3 shall in no way be construed to
      relieve Tenant from obtaining the express consent in writing to Landlord
      to any further assignment or subletting.

5.7   To defend with counsel first approved by Landlord (which approval shall
      not be unreasonably withheld or delayed), save harmless, and indemnify
      Landlord from any liability for injury, loss, accident or damage to any
      person or property, and from any claims, actions, proceedings and expenses
      and costs in connection therewith (including without limitation reasonable
      counsel fees) (i) to the extent arising from or claimed to have arisen
      from (a) the omission, fault, willful act, negligence or other misconduct
      of Tenant or Tenant's contractors, licensees, invitees, agents, servants,
      independent contractors or employees or (b) any use made or thing done or
      occurring on the Premises not due to the omission, fault, willful act,
      negligence or other misconduct of Landlord or not due to structural
      alterations, new construction or demolition operations performed by or on
      behalf of Landlord, or (ii) resulting from the failure of Tenant to
      perform and discharge its covenants and obligations under this Lease;
      provided, however, (x) that with respect to the omission, fault, willful
      act, negligence or other misconduct of any third parties for whom Tenant
      is not legally responsible (hereinafter in this Section called "Third
      Parties"), Tenant's indemnify therefor shall be limited to the amount of
      the liability insurance required to be maintained by Tenant pursuant to
      this Lease so long as Landlord is not precluded from maintaining an action
      or pursuing its remedies against such Third Parties and Landlord's
      recovery from such Third Parties is not limited hereby and (y) that with
      respect to a claim brought against Landlord as to which indemnification is
      sought by Landlord from Tenant, Landlord shall give Tenant reasonably
      prompt notice after Landlord's receipt of actual notice of such claim so
      as to afford Tenant the opportunity to defend such claim and (z) Tenant
      shall have the right to settle such claim

                                      -34-

<PAGE>   35

      provided Landlord is fully released therefrom without payment by Landlord
      and Landlord otherwise first consents thereto, such consent not to be
      unreasonably withheld; to maintain commercial general liability insurance
      or comprehensive general liability insurance written on an occurrence
      basis with a broad form comprehensive liability endorsement covering the
      Premises insuring Landlord and Landlord's managing agent (and such persons
      as are in privity of estate with Landlord and Landlord's managing agent as
      may be set out in notice from time to time) as additional insureds as well
      as Tenant with limits which shall, at the commencement of the Term, be at
      least equal to those stated in Section 1.1 and from time to time during
      the Term shall be for such higher limits, if any, as are customarily
      carried in Greater Boston with respect to similar properties or which may
      reasonably be required by Landlord (Landlord agreeing not to request
      higher limits during the Original Term), and workmen's compensation
      insurance with statutory limits covering all of Tenant's employees working
      in the Premises, and to deposit with Landlord on or before the
      Commencement Date and concurrent with all renewals thereof, certificates
      for such insurance bearing the endorsement that the policies will not be
      canceled until after thirty (30) days' written notice to Landlord. All
      insurance required to be maintained by Tenant pursuant to this Lease shall
      be maintained with responsible companies qualified to do business, and in
      good standing, in the Commonwealth of Massachusetts reasonably approved by
      Landlord.

5.8   That all of the furnishings, fixtures, equipment, effects and property of
      every kind, nature and description of Tenant and of all persons claiming
      by, through or under Tenant which, during the continuance of this Lease or
      any occupancy of the Premises by Tenant or anyone claiming under Tenant,
      may be on the Premises or elsewhere in the Building or on the Site, shall
      be at the sole risk and hazard of Tenant, and if the whole or any part
      thereof shall be destroyed or damaged by fire, water or otherwise, or by
      the leakage or bursting of water pipes, or other pipes, by theft or from
      any other cause, no part of said loss or damage is to be charged to or be
      borne by Landlord, except that Landlord shall in no event be indemnified
      or held harmless or exonerated from any liability to Tenant or to any
      other person, for any injury, loss, damage or liability to the extent such
      indemnity, hold harmless or exoneration is prohibited by law. Further,
      Tenant, at Tenant's expense, shall maintain at all times during the Term
      of this Lease insurance against loss or damage covered by the so-called
      "all risk" type insurance coverage with respect to Tenant's fixtures,
      equipment, goods, wares and merchandise, tenant improvements made by or
      paid for by Tenant, and other property of Tenant (collectively "Tenant's
      Property"). Such insurance shall be in an amount at least equal to the
      full replacement cost of Tenant's Property.

5.9   To permit Landlord and its agents to examine the Premises at reasonable
      times and, if Landlord shall so elect, to make any repairs or replacements
      Landlord may deem necessary; to remove, at Tenant's expense, any
      alterations, addition, signs, curtains,

                                      -35-

<PAGE>   36
      blinds, shades, awnings, aerials, flagpoles, or the like not consented to
      in writing; and to show the Premises to prospective tenants during the
      nine (9) months preceding expiration of the Term and to prospective
      purchasers and mortgagees at all reasonable times.

5.10  Not to place a load upon the Premises exceeding an average rate of 100
      pounds of live load per square foot of floor area (partitions shall be
      considered as part of the live load); and not to move any safe, vault or
      other heavy equipment in, about or out of the Premises except in such
      manner and at such time as Landlord shall in each instance authorize;
      Tenant's business machines and mechanical equipment which cause vibration
      or noise that may be transmitted to the Building structure or to any other
      space in the Building shall be so installed, maintained and used by Tenant
      so as to eliminate such vibration or noise.

5.11  To pay promptly when due all taxes which may be imposed upon Tenant's
      Property in the Premises to whomever assessed.

5.12  To comply with all applicable Legal Requirements now or hereafter in force
      which shall impose a duty on Landlord or Tenant relating to or as a result
      of the use or occupancy of the Premises; provided that Tenant shall not be
      required to make any alterations or additions to the structure, roof,
      exterior and load bearing walls, foundation, structural floor slabs and
      other structural elements of the Building unless the same are required by
      such Legal Requirements as a result of or in connection with Tenant's use
      or occupancy of the Premises beyond normal use of space of this kind.
      Tenant shall promptly pay all fines, penalties and damages that may arise
      out of or be imposed because of its failure to comply with the provisions
      of this Section 5.12. Landlord represents to Tenant that the Permitted
      Uses are permitted in the Premises under the applicable Town of Lexington
      Zoning By-Law.

5.13  To pay as Additional Rent all reasonable costs, counsel and other fees
      incurred by Landlord in connection with the successful enforcement by
      Landlord of any obligations of Tenant under this Lease.


                                   ARTICLE VI
                                   ----------

                    LANDLORD'S INSURANCE CASUALTY AND TAKING
                    ----------------------------------------

6.0   Landlord shall maintain in full force from the date upon which Tenant
      first enters the Premises for any reason, throughout the Term, and
      thereafter so long as Tenant is in occupancy of any part of the Premises,
      a policy of insurance upon the Building and Landlord's furniture,
      fixtures, and other equipment insuring against all risks of physical

                                      -36-
 
<PAGE>   37

      loss or damage under an All Risk coverage endorsement in an amount at
      least equal to the full replacement value of the property insured (as
      reasonably determined by Landlord), with an Agreed Amount endorsement to
      satisfy co-insurance requirements, as well as insurance against breakdown
      of boilers and other machinery as customarily insured against. Upon
      request of Tenant from time to time, a certificate of such insurance shall
      be delivered to Tenant. Such insurance may be written with a deductible as
      determined by Landlord. Further, if at any time during the Term all risk
      type insurance coverage shall cease to be written, then the type of fire
      and casualty insurance and amount of coverage shall be as determined by
      Landlord. Landlord may also maintain such other insurance as may from time
      to time be required by any mortgagee holding a first mortgage lien on the
      Site. In addition, Landlord may also maintain such insurance against loss
      of Annual Fixed Rent and Additional Rent and such other risks and perils
      as Landlord deems proper. Any and all such insurance together with the
      liability insurance required or permitted to be carried under this Lease
      by Landlord may be maintained under a blanket policy affecting other
      premises of Landlord and/or affiliated business organizations.

6.1   In case during the Lease Term the Building or the Site are damaged by fire
      or other casualty and such fire or casualty damage cannot, in the ordinary
      course, reasonably be expected to be repaired within one hundred fifty
      (150) days from the time that repair work would commence, Landlord may, at
      its election, terminate this Lease by notice given to Tenant within sixty
      (60) days after the date of such fire or other casualty, specifying the
      effective date of termination. The effective date of termination specified
      by Landlord shall not be less than thirty (30) days nor more than
      forty-five (45) days after the date of notice of such termination.

      In case during the Lease Term, the Premises are damaged by fire or other
      casualty and such fire or casualty damage cannot, in the ordinary course,
      reasonably be expected to be repaired within two hundred forty (240) days
      (and/or as to special work or work which requires long lead time then if
      such work cannot reasonably be expected to be repaired within such
      additional time as is reasonable under the circumstances given the nature
      of the work) from the time that repair work would commence, Tenant may, at
      its election, terminate this Lease by notice given to Landlord within
      thirty (30) days after the date of such fire or other casualty, specifying
      the effective date of termination. The effective date of termination
      specified by Tenant shall be not less than thirty (30) days nor more than
      forty-five (45) days after the date of notice of such termination.

      However, in case during the last year of the Lease Term, the Premises are
      damaged by fire or other casualty and such fire or casualty damage cannot,
      in the ordinary course, reasonably be expected to be repaired within one
      hundred fifty (150) days (and/or as to special work or work which requires
      long lead time then if such work cannot reasonably

                                      -37-
 
<PAGE>   38

      be expected to be repaired within such additional time as is reasonable
      under the circumstances given the nature of the work) from the time that
      repair work would commence, Tenant may, at its election, terminate this
      Lease by notice given to Landlord within thirty (30) days after the date
      of such fire or other casualty, specifying the effective date of
      termination. The effective date of termination specified by Tenant shall
      be not less than thirty (30) days nor more than forty-five (45) days after
      the date of notice of such termination.

      Unless terminated pursuant to the foregoing provisions, this Lease shall
      remain in full force and effect following any such damage subject,
      however, to the following provisions.

      If the Building or the Site or any part thereof are damaged by fire or
      other casualty and this Lease is not so terminated, or Landlord or Tenant
      have no right to terminate this Lease, and in any such case the holder of
      any mortgage which includes the Building as a part of the mortgaged
      premises or any ground lessor of any ground lease which includes the Site
      as part of the demised premises allows the net insurance proceeds to be
      applied to the restoration of the Building (and/or the Site), Landlord
      shall, promptly after such damage and the determination of the net amount
      of insurance proceeds available, use due diligence to restore the Premises
      and the Building in the event of damage thereto (excluding Tenant's
      Property) into proper condition for use and occupation and a just
      proportion of the Annual Fixed Rent, Tenant's share of Operating Costs and
      Tenant's share of real estate taxes shall be abated according to the
      nature and extent of the injury to the Premises, until the Premises shall
      have been restored by Landlord substantially into such condition except
      for punch list items and long lead items. Notwithstanding anything herein
      contained to the contrary, Landlord shall not be obligated to expend for
      such repair and restoration any amount in excess of the net insurance
      proceeds.

      If such restoration is not completed within eleven (11) months from the
      date of the fire or casualty, such period to be subject, however, to
      extension where the delay in completion of such work is due to causes
      beyond Landlord's reasonable control (but in no event beyond fifteen (15)
      months from the date of the fire or casualty), Tenant shall have the right
      to terminate this Lease at any time after the expiration of such one-year
      period (as extended), which right shall continue until the restoration is
      substantially completed. Such termination shall be effective as of the
      thirtieth (30th) day after the date of receipt by Landlord of Tenant's
      notice, with the same force and effect as if such date were the date
      originally established as the expiration date hereof unless, within thirty
      (30) days after Landlord's receipt of Tenant's notice, such restoration is
      substantially completed, in which case Tenant's notice of termination
      shall be of no force and effect and this Lease and the Lease Term shall
      continue in full force and effect.


                                      -38-
 
<PAGE>   39


6.2   Notwithstanding anything to the contrary contained in this Lease, if the
      Building or the Premises shall be substantially damaged by fire or
      casualty as the result of a risk not covered by the forms of casualty
      insurance at the time maintained by Landlord and such fire or casualty
      damage cannot, in the ordinary course, reasonably be expected to be
      repaired within ninety (90) days from the time that repair work would
      commence, Landlord may, at its election, terminate the Term of this Lease
      by notice to the Tenant given within thirty (30) days after such loss. If
      Landlord shall give such notice, then this Lease shall terminate as of the
      date of such notice with the same force and effect as if such date were
      the date originally established as the expiration date hereof.

6.3   If the entire Building, or such portion of the Premises as to render the
      balance (if reconstructed to the maximum extent practicable in the
      circumstances) unsuitable for Tenant's purposes, shall be taken by
      condemnation or right of eminent domain, Landlord or Tenant shall have the
      right to terminate this Lease by notice to the other of its desire to do
      so, provided that such notice is given not later than thirty (30) days
      after Tenant has been deprived of possession. If either party shall give
      such notice, then this Lease shall terminate as of the date of such notice
      with the same force and effect as if such date were the date originally
      established as the expiration date hereof.

      Further, if so much of the Building shall be so taken that continued
      operation of the Building would be uneconomic as a result of the taking,
      Landlord shall have the right to terminate this Lease by giving notice to
      Tenant of Landlord's desire to do so not later than thirty (30) days after
      Landlord receives written notice of such taking. If Landlord shall give
      such notice, then this Lease shall terminate as of the date of such notice
      with the same force and effect as if such date were the date originally
      established as the expiration date hereof.

      Should any part of the Premises be so taken or condemned during the Lease
      Term hereof, and should this Lease not be terminated in accordance with
      the foregoing provisions, and the holder of any mortgage which includes
      the Premises as part of the mortgaged premises or any ground lessor of any
      ground lease which includes the Site as part of the demised premises
      allows the net condemnation proceeds to be applied to the restoration of
      the Building, Landlord agrees, after the determination of the net amount
      of condemnation proceeds available to Landlord, to use due diligence to
      put what may remain of the Premises into proper condition for use and
      occupation as nearly like the condition of the Premises prior to such
      taking as shall be practicable (excluding Tenant's Property).
      Notwithstanding the foregoing, Landlord shall not be obligated to expend
      for such repair and restoration any amount in excess of the net
      condemnation proceeds.

      If the Premises shall be affected by any exercise of the power of eminent
      domain, then the Annual Fixed Rent, Tenant's share of operating costs and
      Tenant's share of real estate

                                      -39-
<PAGE>   40

      taxes shall be justly and equitably abated and reduced according to the
      nature and extent of the loss of use thereof suffered by Tenant; and in
      case of a taking which permanently reduces the Rentable Floor Area of the
      Premises, a just proportion of the Annual Fixed Rent, Tenant's share of
      operating costs and Tenant's share of real estate taxes shall be abated
      for the remainder of the Lease Term.

6.4   Landlord shall have and hereby reserves to itself any and all rights to
      receive awards made for damages to the Premises, the Building, the Complex
      and the Site and the leasehold hereby created, or any one or more of them,
      accruing by reason of exercise of eminent domain or by reason of anything
      lawfully done in pursuance of public or other authority. Tenant hereby
      grants, releases and assigns to Landlord all Tenant's rights to such
      awards, and covenants to execute and deliver such further assignments and
      assurances thereof as Landlord may from time to time request, and if
      Tenant shall fail to execute and deliver the same within fifteen (15) days
      after notice from Landlord, Tenant hereby covenants and agrees that
      Landlord shall be irrevocably designated and appointed as its
      attorney-in-fact to execute and deliver in Tenant's name and behalf all
      such further assignments thereof which conform with the provisions hereof.

      Nothing contained herein shall be construed to prevent Tenant from
      prosecuting in any condemnation proceeding a claim for the value of any of
      Tenant's usual trade fixtures installed in the Premises by Tenant at
      Tenant's expense and for relocation and moving expenses, provided that
      such action and any resulting award shall not affect or diminish the
      amount of compensation otherwise recoverable by Landlord from the taking
      authority.


                                   ARTICLE VII
                                   -----------

                                     DEFAULT
                                     -------

7.1   (a) If at any time subsequent to the date of this Lease any one or more of
      the following events (herein sometimes called an "Event of Default") shall
      occur:

           (i)    Tenant shall fail to pay the fixed rent, Additional Rent or
                  other charges for which provision is made herein on or before
                  the date on which the same become due and payable, and the
                  same continues for ten (10) days after notice from Landlord
                  thereof, or

           (ii)   Landlord having rightfully given the notice specified in
                  subdivision (a) above twice in any calendar year, Tenant shall
                  thereafter in the same calendar year fail to pay the fixed
                  rent, Additional Rent or other charges

                                      -40-
 
<PAGE>   41



                  on or before the date on which the same become due and
                  payable and the same continues for two (2) business days after
                  notice from Landlord thereof, or,

           (iii)  Tenant shall neglect or fail to perform or observe any other
                  covenant herein contained on Tenant's part to be performed or
                  observed and Tenant shall fail to remedy the same within
                  thirty (30) days after notice to Tenant specifying such
                  neglect or failure, or if such failure is of such a nature
                  that Tenant cannot reasonably remedy the same within such
                  thirty (30) day period, Tenant shall fail to commence promptly
                  to remedy the same and to prosecute such remedy to completion
                  with diligence and continuity; or

           (iv)   Tenant's leasehold interest in the Premises shall be taken on
                  execution or by other process of law directed against Tenant;
                  or

           (v)    Tenant shall make an assignment for the benefit of creditors
                  or shall file a voluntary petition in bankruptcy or shall be
                  adjudicated bankrupt or insolvent, or shall file any petition
                  or answer seeking any reorganization, arrangement,
                  composition, readjustment, liquidation, dissolution or similar
                  relief for itself under any present or future Federal, State
                  or other statute, law or regulation for the relief of debtors,
                  or shall seek or consent to or acquiesce in the appointment of
                  any trustee, receiver or liquidator of Tenant or of all or any
                  substantial part of its properties, or shall admit in writing
                  its inability to pay its debts generally as they become due;
                  or

           (vi)   A petition shall be filed against Tenant in bankruptcy or
                  under any other law seeking any reorganization, arrangement,
                  composition, readjustment, liquidation, dissolution, or
                  similar relief under any present or future Federal, State or
                  other statute, law or regulation and shall remain undismissed
                  or unstayed for an aggregate of sixty (60) days (whether or
                  not consecutive), or if any debtor in possession (whether or
                  not Tenant) trustee, receiver or liquidator of Tenant or of
                  all or any substantial part of its properties or of the
                  Premises shall be appointed without the consent or
                  acquiescence of Tenant and such appointment shall remain
                  unvacated or unstayed for an aggregate of sixty (60) days
                  (whether or not consecutive)--

      then after the applicable notice and cure period when no cure has been
      fully effected, and in any of said cases (notwithstanding any license of a
      former breach of covenant or waiver of the benefit hereof or consent in a
      former instance, Landlord lawfully may, immediately or at any time
      thereafter, and without demand or further notice terminate this Lease by
      notice to Tenant, specifying a date not less than twenty (20) days after
      the

                                      -41-
 
<PAGE>   42

      giving of such notice on which this Lease shall terminate, and this Lease
      shall come to an end on the date specified therein as fully and completely
      as if such date were the date herein originally fixed for the expiration
      of the Lease Term (Tenant hereby waiving any rights of redemption), and
      Tenant will then quit and surrender the Premises to Landlord, but Tenant
      shall remain liable as hereinafter provided.

      (b) If This Lease shall have been terminated as provided in this Article,
      then Landlord may, without notice, re-enter the Premises, either by
      force, summary proceedings, ejectment or otherwise, and remove and
      dispossess Tenant and all other persons and any and all property from the
      same, as if this Lease had not been made, and Tenant hereby waives the
      service of notice of intention to re-enter or to institute legal
      proceedings to that end.

      (c) In the event that this Lease is terminated under any of the provisions
      contained in Section 7.1 (a) or shall be otherwise terminated by breach of
      any obligation of Tenant, Tenant covenants and agrees forthwith to pay and
      be liable for, on the days originally fixed herein for the payment
      thereof, amounts equal to the several installments of rent and other
      charges reserved as they would, under the terms of this Lease, become due
      if this Lease had not been terminated or if Landlord had not entered or
      re-entered, as aforesaid, and whether the Premises be relet or remain
      vacant, in whole or in part, or relet for a period less than the remainder
      of the Term, and for the whole thereof, but in the event the Premises be
      relet by Landlord, Tenant shall be entitled to a credit in the net amount
      of rent and other charges received by Landlord in reletting, after
      deduction of all expenses incurred in reletting the Premises (including,
      without limitation, remodeling costs, brokerage fees and the like), and in
      collecting the rent in connection therewith, in the following manner:

      Amounts received by Landlord after reletting shall first be applied
      against such Landlord's expenses, until the same are recovered, and until
      such recovery, Tenant shall pay, as of each day when a payment would fall
      due under this Lease, the amount which Tenant is obligated to pay under
      the terms of this Lease (Tenant's liability prior to any such reletting
      and such recovery not in any way to be diminished as a result of the fact
      that such reletting might be for a rent higher than the rent provided for
      in this Lease); when and if such expenses have been completely recovered,
      the amounts received from reletting by Landlord as have not previously
      been applied shall be credited against Tenant's obligations as of each day
      when a payment would fall due under this Lease, and only the net amount
      thereof shall be payable by Tenant. Further, amounts received by Landlord
      from such reletting for any period shall be credited only against
      obligations of Tenant allocable to such period, and shall not be credited
      against obligations of Tenant hereunder accruing subsequent or prior to
      such period; nor shall any credit of any kind be

                                      -42-
 
<PAGE>   43

      due for any period after the date when the term of this Lease is scheduled
      to expire according to its terms.

      (d)(i) At any time after such termination and whether or not Landlord
      shall have collected any damages as aforesaid, Tenant shall pay to
      Landlord as liquidated final damages and in lieu of all other damages
      beyond the date of notice from Landlord to Tenant, at Landlord's election,
      such a sum as at the time of the giving of such notice represents the
      amount of the excess, if any, of the then cash value (in advance) of the
      total rent and other benefits which would have accrued to Landlord under
      this Lease from the date of such notice for what would be the then
      unexpired Lease Term if the Lease terms had been fully complied with by
      Tenant over and above the then cash rental value (in advance) of the
      Premises for the balance of the Lease Term.

      (d)(ii) For the purposes of this Article, if Landlord elects to require
      Tenant to pay damages in accordance with the immediately preceding
      paragraph, the total rent shall be computed by assuming that Tenant's
      share of excess taxes, Tenant's share of excess operating costs and
      Tenant's share of excess electrical costs would be, for the balance of the
      unexpired Term from the date of such notice, the amount thereof (if any)
      for the immediately preceding annual period payable by Tenant to Landlord.

      (e) In case of any Event of Default, re-entry, dispossession by summary
      proceedings or otherwise, Landlord may (i) relet the Premises or any part
      or parts thereof, either in the name of Landlord or otherwise, for a term
      or terms which may at Landlord's option be equal to or less than or exceed
      the period which would otherwise have constituted the balance of the Term
      of this Lease and may grant concessions or free rent to the extent that
      Landlord considers advisable or necessary to relet the same and (ii) may
      make such alterations, repairs and decorations in the Premises as Landlord
      in its sole judgment considers advisable or necessary for the purpose of
      reletting the Premises; and the making of such alterations, repairs and
      decorations shall not operate or be construed to release Tenant from
      liability hereunder as aforesaid. Landlord shall use reasonable efforts to
      relet the Premises after Tenant vacates the Premises (which reasonable
      efforts shall be deemed satisfied by Landlord offering the Premises for
      lease either directly or through a commercial real estate leasing broker
      or brokerage firm) but the failure to relet in whole or in part shall not
      give rise to any claim, action or counterclaim by Tenant nor release,
      limit, reduce, affect or otherwise modify Tenant's liability. Also,
      Landlord shall in no event be liable in any way whatsoever for failure to
      relet the Premises, or, in the event that the Premises are relet, for
      failure to collect the rent under reletting. Tenant hereby expressly
      waives any and all rights of redemption granted by or under any present or
      future laws in the event of Tenant being evicted or dispossessed, or in
      the event of Landlord obtaining possession of the Premises, by reason of
      the violation by Tenant of any of the covenants and conditions of this
      Lease.

                                      -43-
 
<PAGE>   44

      (f) Except as provided in Subsection (d)(i) above, the specified remedies
      to which Landlord may resort hereunder are not intended to be exclusive of
      any remedies or means of redress to which Landlord may at any time be
      entitled lawfully, and Landlord may invoke any remedy (including the
      remedy of specific performance) allowed at law or in equity as if specific
      remedies were not herein provided for. Further, nothing contained in this
      Lease shall limit or prejudice the right of Landlord to prove and obtain
      in proceedings for bankruptcy or insolvency by reason of the termination
      of this Lease, an amount equal to the maximum allowed by any statute or
      rule of law in effect at the time when, and governing the proceedings in
      which, the damages are to be proved, whether or not the amount be greater,
      equal to, or less than the amount of the loss or damages referred to
      above.

7.2   Landlord shall in no event be in default in the performance of any of
      Landlord's obligations hereunder unless and until Landlord shall have
      failed to perform such obligations within thirty (30) days, or such
      additional time as is reasonably required to correct any such default,
      after notice by Tenant to Landlord properly specifying wherein Landlord
      has failed to perform any such obligation.


                                  ARTICLE VIII
                                  ------------

8.1   Tenant covenants and agrees that Tenant will not do or permit anything to
      be done in or upon the Premises, or bring in anything or keep anything
      therein, which shall invalidate or increase the rate of insurance on the
      Premises or on the Building above the standard rate applicable to premises
      being occupied for the use to which Tenant has agreed to devote the
      Premises; and Tenant further agrees that, in the event that Tenant shall
      do any of the foregoing, Tenant will promptly pay to Landlord, on demand,
      any such increase resulting therefrom, which shall be due and payable as
      Additional Rent thereunder.

8.2   Failure on the part of Landlord or Tenant to complain of any action or
      non-action on the part of the other, no matter how long the same may
      continue, shall never be a waiver by Tenant or Landlord, respectively, of
      any of its rights hereunder. Further, no waiver at any time of any of the
      provisions hereof by Landlord or Tenant shall be construed as a waiver of
      any of the other provisions hereof, and a waiver at any time of any of the
      provisions hereof shall not be construed as a waiver at any subsequent
      time of the same provisions. The consent or approval of Landlord or Tenant
      to or of any action by the other requiring such consent or approval shall
      not be construed to waive or render unnecessary Landlord's or Tenant's
      consent or approval to or of subsequent similar act by the other.

      No payment by Tenant, or acceptance by Landlord, of a lesser amount than
      shall be due from Tenant to Landlord shall be treated otherwise than as a
      payment on account. The

                                      -44-
 
<PAGE>   45

      acceptance by Landlord of a check for a lesser amount with an endorsement
      or statement thereon, or upon any letter accompanying such check, that
      such lesser amount is payment in full, shall be given no effect, and
      Landlord may accept such check without prejudice to any other rights or
      remedies which Landlord may have against Tenant.

8.3   The specific remedies to which Landlord may resort under the terms of this
      Lease are cumulative and are not intended to be exclusive of any other
      remedies or means of redress to which such party may be lawfully entitled
      in case of any breach or threatened breach by Tenant of any provisions of
      this Lease. In addition to the other remedies provided in this Lease,
      Landlord shall be entitled to the restraint by injunction of the violation
      or attempted or threatened violation of any of the covenants, conditions
      or provisions of this Lease or to a decree compelling specific performance
      of any such covenants, conditions or provisions.

8.4   Tenant, subject to the terms and provisions of this Lease on payment of
      the rent and observing, keeping and performing all of the terms and
      provisions of this Lease on Tenant's part to be observed, kept and
      performed, shall lawfully, peaceably and quietly have, hold, occupy and
      enjoy the Premises during the Term, without hindrance or ejection by any
      persons lawfully claiming under Landlord to have title to the Premises
      superior to Tenant; the foregoing covenant of quiet enjoyment is in lieu
      of any other covenant, express or implied; and it is understood and agreed
      that this covenant and any and all other covenants of Landlord contained
      in this Lease shall be binding upon Landlord and Landlord's successors
      only with respect to breaches occurring during Landlord's or Landlord's
      successors' respective ownership of Landlord's interest hereunder, as the
      case may be.

      Further, Tenant specifically agrees to look solely to Landlord's then
      equity interest in the Building at the time owned, or in which Landlord
      holds an interest as ground lessee, for recovery of any judgment from
      Landlord; it being specifically agreed that neither Landlord (original or
      successor), nor any partner in or of Landlord, nor any beneficiary of any
      Trust of which any person holding Landlord's interest is Trustee, shall
      ever be personally liable for any such judgment, or for the payment of any
      monetary obligation to Tenant. The provision contained in the foregoing
      sentence is not intended to, and shall not, limit any right that Tenant
      might otherwise have to obtain injunctive relief against Landlord or
      Landlord's successors in interest, or any action not involving the
      personal liability of Landlord (original or successor), any partner in or
      of Landlord, any successor Trustee to the persons named herein as
      Landlord, or any beneficiary of any Trust of which any person holding
      Landlord's interest is Trustee, to respond in monetary damages from
      Landlord's assets other than Landlord's equity interest aforesaid in the
      Building. In no event shall Landlord ever be liable to Tenant for any
      indirect or consequential

                                      -45-
 
<PAGE>   46

      damages suffered by Tenant from whatever cause or for any special or
      punitive damages of whatever nature.

8.5   After receiving notice from any person, firm or other entity that it holds
      a mortgage which includes the Premises as part of the mortgaged premises,
      or that it is the ground lessor under a lease with Landlord, as ground
      lessee, which includes the Premises as a part of the demised premises, no
      notice from Tenant to Landlord shall be effective unless and until a copy
      of the same is given to such holder or ground lessor, and the curing of
      any of Landlord's defaults by such holder or ground lessor within a
      reasonable time thereafter (including a reasonable time to obtain
      possession of the premises if the mortgagee or ground lessor elects to do
      so) shall be treated as performance by Landlord. For the purposes of this
      Section 8.5 or Section 8.15, the term "mortgage" includes a mortgage on a
      leasehold interest of Landlord (but not one on Tenant's leasehold
      interest).

8.6   With reference to any assignment by Landlord or Landlord's interest in
      this Lease, or the rents payable hereunder, conditional in nature or
      otherwise, which assignment is made to the holder of a mortgage or ground
      lease on property which includes the Premises, Tenant agrees:

           (a)    That the execution thereof by Landlord, and the acceptance
                  thereof by the holder of such mortgage or the ground lessor,
                  shall never be treated as an assumption by such holder or
                  ground lessor of any of the obligations of Landlord hereunder,
                  unless such holder, or ground lessor, shall, by notice sent to
                  Tenant, specifically otherwise elect; and

           (b)    That, except as aforesaid, such holder or ground lessor shall
                  be treated as having assumed Landlord's obligations hereunder
                  only upon foreclosure of such holder's mortgage and the taking
                  of possession of the Premises, or, in the case of a ground
                  lessor, the assumption of Landlord's position hereunder by
                  such ground lessor.

                  In no event shall the acquisition of title to the Building and
                  the land on which the same is located by a purchaser which,
                  simultaneously therewith, leases the entire Building or such
                  land back to the seller thereof be treated as an assumption by
                  such purchaser-lessor, by operation of law or otherwise, of
                  Landlord's obligations hereunder, but Tenant shall look solely
                  to such seller-lessee, and its successors from time to time in
                  title, for performance of Landlord's obligations hereunder
                  subject to the provisions of Section 8.4 hereof. In any such
                  event, this Lease shall be subject and subordinate to the
                  lease to such purchaser provided that such purchaser agrees to
                  recognize the right of Tenant to use and occupy the Premises

                                      -46-

<PAGE>   47

                  upon the payment of rent and other charges payable by Tenant
                  under this Lease and the performance by Tenant of Tenant's
                  obligations under this Lease and provided that Tenant agrees
                  to attorn to such purchaser. For all purposes, such
                  seller-lessee, and its successors in title, shall be the
                  landlord hereunder unless and until Landlord's position shall
                  have been assumed by such purchaser-lessor.

8.7   No act or thing done by Landlord during the Lease Term shall be deemed an
      acceptance of a surrender of the Premises, and no agreement to accept such
      surrender shall be valid, unless in writing signed by Landlord. No
      employee of Landlord or of Landlord's agents shall have any power to
      accept the keys of the Premises prior to the termination of this Lease.
      The delivery of keys to any employee of Landlord or of Landlord's agents
      shall not operate as a termination of the Lease or a surrender of the
      Premises.

8.8   (A) Tenant warrants and represents that Tenant has not dealt with any
      broker, finder or other agent in connection with the consummation of this
      Lease other than the Recognized Brokers designated in Section 1.1 hereof;
      and in the event any claim is made against the Landlord relative to
      dealings by Tenant with brokers, finders or other agents other than the
      Recognized Brokers designated in Section 1.1 hereof, Tenant shall defend
      the claim against Landlord with counsel of Tenant's selection first
      approved by Landlord (which approval will not be unreasonably withheld)
      and save harmless and indemnify Landlord on account of loss, cost or
      damage which may arise by reason of such claim.

      (B) Landlord warrants and represents that Landlord has not dealt with any
      broker, finder or other agent in connection with the consummation of this
      Lease other than the Recognized Brokers designated in Section 1.1 hereof;
      and in the event any claim is made against the Tenant relative to dealings
      by Landlord with brokers, finders or other agents other than the
      Recognized Brokers designated in Section 1.1 hereof, Landlord shall defend
      the claim against Tenant with counsel of Landlord's selection and save
      harmless and indemnify Tenant on account of loss, cost or damage which may
      arise by reason of such claim. Landlord agrees that it shall be solely
      responsible for the payment of brokerage commissions to the Recognized
      Brokers designated in Section 1.1 hereof.

8.9   If any term or 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 term or provision
      to persons or circumstances other than those as to which it is held
      invalid or unenforceable, shall not be affected thereby, and each term and
      provision of this Lease shall be valid and be enforced to the fullest
      extent permitted by law.


                                      -47-
<PAGE>   48

8.10  The obligations of this Lease shall run with the land, and except as
      herein otherwise provided, the terms hereof shall be binding upon and
      shall inure to the benefit of the successors and assigns, respectively, of
      Landlord and Tenant and, if Tenant shall be an individual, upon and to his
      heirs, executors, administrators, successors and assigns. Each term and
      each provision of this Lease to be performed by Tenant shall be construed
      to be both a covenant and a condition. The reference contained to
      successors and assigns of Tenant is not intended to constitute a consent
      to subletting or assignment by Tenant.

8.11  Tenant agrees not to record the within Lease, but each party hereto
      agrees, on the request of the other, to execute a so-called Notice of
      Lease or short form lease in form recordable and complying with applicable
      law and reasonably satisfactory to both Landlord's and Tenant's attorneys.
      In no event shall such document set forth rent or other charges payable by
      Tenant under this Lease; and any such document shall expressly state that
      it is executed pursuant to the provisions contained in this Lease, and is
      not intended to vary the terms and conditions of this Lease.

8.12  Whenever, by the terms of this Lease, notice shall or may be given either
      to Landlord or to Tenant, such notice shall be in writing and shall be
      sent by registered or certified mail postage prepaid:

           If intended for Landlord, addressed to Landlord at the address set
           forth on the first page of this Lease (or to such other address or
           addresses as may from time to time hereafter be designated by
           Landlord by like notice) with a copy to Landlord, Attention: General
           Counsel.

           If intended for Tenant, addressed to Tenant, Attention: President at
           the address set forth on the second page of this Lease except that
           from and after the Commencement Date the address of Tenant shall be
           the Premises (or to such other address or addresses as may from time
           to time hereafter be designated by Tenant by like notice) with a copy
           to Tenant, Attention: General Counsel.

      Except as otherwise provided herein, all such notices shall be effective
      when received; provided, that (i) if receipt is refused, notice shall be
      effective upon the first occasion that such receipt is refused or (ii) if
      the notice is unable to be delivered due to a change of address of which
      no notice was given, notice shall be effective upon the date such delivery
      was attempted.

      Where provision is made for the attention of an individual or department,
      the notice shall be effective only if the wrapper in which such notice is
      sent is addressed to the attention of such individual or department.


                                      -48-
 
<PAGE>   49

      Time is of the essence with respect to any and all notices and periods for
      giving notice or taking any action thereto under this Lease.

8.13  Employees or agents of Landlord have no authority to make or agree to make
      a lease or any other agreement or undertaking in connection herewith. The
      submission of this document for examination and negotiation does not
      constitute an offer to lease, or a reservation of, or option for, the
      Premises, and this document shall become effective and binding only upon
      the execution and delivery hereof by both Landlord and Tenant. All
      negotiations, considerations, representations and understandings between
      Landlord and Tenant are incorporated herein and may be modified or altered
      only by written agreement between Landlord and Tenant, and no act or
      omission of any employee or agent of Landlord shall alter, change or
      modify any of the provisions hereof.

8.14  The titles of the Articles throughout this Lease are for convenience and
      reference only, and the words contained therein shall in no way be held to
      explain, modify, amplify or aid in the interpretation, construction or
      meaning of the provisions of this Lease.

8.15  This Lease shall be subject and subordinate to any mortgage now or
      hereafter on the Site or the Building, or both, and to each advance made
      or hereafter to be made under any mortgage, and to all renewals,
      modifications, consolidations, replacements and extensions thereof and all
      substitutions therefor provided that the holder of such mortgage agrees to
      recognize the rights of Tenant under this Lease (including the right to
      use and occupy the Premises) upon the payment of rent and other charges
      payable by Tenant under this Lease and the performance by Tenant of
      Tenant's obligations hereunder in which event Tenant shall agree to attorn
      to such holder and its successors as landlord. In confirmation of such
      subordination and recognition, Tenant shall execute and deliver promptly
      such instruments of subordination and recognition as such mortgagee may
      reasonably request. Tenant hereby appoints such mortgagee (from time to
      time) as Tenant's attorney-in-fact to execute such subordination upon
      default of Tenant in complying with such mortgagee's (from time to time)
      request. In the event that any mortgagee or its respective successor in
      title shall succeed to the interest of Landlord, then, this Lease shall
      nevertheless continue in full force and effect and Tenant shall and does
      hereby agree to attorn to such mortgagee or successor and to recognize
      such mortgagee or successor as its landlord. If any holder of a mortgage
      which includes the Premises, executed and recorded prior to the date of
      this Lease, shall so elect, this Lease and the rights of Tenant hereunder,
      shall be superior in right to the rights of such holder, with the same
      force and effect as if this Lease had been executed, delivered and
      recorded, or a statutory Notice hereof recorded, prior to the execution,
      delivery and recording of any such mortgage. The election of any such
      holder shall become effective upon either notice from such holder to
      Tenant in the same fashion as notices from Landlord to Tenant are to be
      given hereunder or by the recording in the appropriate registry or
      recorder's office of an instrument in which such

                                      -49-
 
<PAGE>   50

      holder subordinates its rights under such mortgage to this Lease. With
      respect to the present mortgage encumbering the Property, on or before the
      Commencement Date, Landlord shall use reasonable efforts to obtain a
      Subordination, Non-Disturbance and Attornment Agreement in substantially
      the form of Exhibit H attached hereto which shall be executed by Landlord,
      Tenant and said mortgagee.

      If in connection with obtaining financing for the Building or Complex, a
      bank, insurance company, pension trust or other institutional lender shall
      request reasonable modifications in this Lease as a condition to such
      financing, Tenant will not unreasonably withhold, delay or condition its
      consent thereto, provided that such modifications do not increase the
      monetary obligations of Tenant hereunder or materially adversely affect
      the leasehold interest hereby created.

8.16  Recognizing that Landlord may find it necessary to establish to third
      parties, such as accountants, banks, potential or existing mortgagees,
      potential purchasers or the like, the then current status of performance
      hereunder, Tenant, on the request of Landlord made from time to time, will
      promptly furnish to Landlord, or any existing or potential holder of any
      mortgage encumbering the Premises, the Building, the Site and/or the
      Complex or any potential purchaser of the Premises, the Building, the Site
      and/or the Complex, (each an "Interested Party"), a statement of the
      status of any matter pertaining to this Lease, including, without
      limitation, acknowledgments that (or the extent to which) each party is in
      compliance with its obligations under the terms of this Lease. In
      addition, Tenant shall deliver to Landlord, or any Interested Party
      designated by Landlord, financial statements of Tenant and any guarantor
      of Tenant's obligations under this Lease, as reasonably requested by
      Landlord, including, but not limited to financial statements for the past
      three (3) years. Any such status statement or financial statement
      delivered by Tenant pursuant to this Section 8.16 may be relied upon by
      any Interested Party.

8.17  If Tenant shall at any time default in the performance of any obligation
      under this Lease, Landlord shall have the right, but shall not be
      obligated, to enter upon the Premises and to perform such obligation
      notwithstanding the fact that no specific provision for such substituted
      performance by Landlord is made in this Lease with respect to such
      default. In performing such obligation, Landlord may make any payment of
      money or perform any other act. All sums so paid by Landlord (together
      with interest at the rate of one and one-half percentage points over the
      then prevailing prime rate in Boston as set by The First National Bank of
      Boston) and all costs and expenses in connection with the performance of
      any such act by Landlord, shall be deemed to be Additional Rent under this
      Lease and shall be payable to Landlord immediately on demand. Landlord may
      exercise the foregoing rights without waiving any other of its rights or
      releasing Tenant from any of its obligations under this Lease.


                                      -50-
 
<PAGE>   51

8.18  Any holding over by Tenant after the expiration of the term of this Lease
      shall be treated as a tenancy at sufferance at one and one-half times the
      rents and other charges herein (prorated on a daily basis) and shall
      otherwise be on the terms and conditions set forth in this Lease, as far
      as applicable; provided, however, that neither the foregoing nor any other
      term or provision of this Lease shall be deemed to permit Tenant to retain
      possession of the Premises or hold over in the Premises after the
      expiration or earlier termination of the Lease Term.

8.19  Any insurance carried by either party with respect to the Premises,
      Building or property therein shall include a clause or endorsement denying
      to the insurer rights of subrogation against the other party to the extent
      rights have been waived by the insured prior to occurrence of injury or
      loss. Each party, notwithstanding any provisions of this Lease to the
      contrary, hereby waives any rights of recovery against the other for
      injury or loss due to hazards covered by such insurance to the extent of
      the indemnification received thereunder.

8.20  (A) Tenant agrees to deposit with Landlord upon the execution and delivery
      of this Lease a security deposit (the "Security Deposit") in the amount of
      $720,000.00 which shall be paid in cash or by wire transfer in either case
      in good funds. Landlord shall hold such Security Deposit in a separate
      interest bearing account (in which Landlord is identified as trustee and
      Tenant is identified as the beneficial owner but in which Landlord (or its
      managing agent) is the sole signatory) at a banking institution and in an
      investment vehicle selected by Tenant, which banking institution and
      investment vehicle shall be subject to Landlord's reasonable prior
      approval. If Tenant shall not select a banking institution or investment
      vehicle or if Landlord shall not reasonably approve either, Landlord shall
      have the right to designate the banking institution and investment
      vehicle. The interest so earned shall be added to and be deemed a part of
      the Security Deposit. Landlord shall hold the Security Deposit throughout
      the term of this Lease , as security for the performance by Tenant of all
      obligations on the part of Tenant to be performed. Landlord shall have the
      right from time to time without prejudice to any other remedy Landlord may
      have on account thereof, to apply the Security Deposit and all interest
      earned thereon, or any part thereof, to Landlord's damages arising from
      any default on the part of Tenant. If Landlord so applies all or any
      portion of such deposit, Tenant shall within seven (7) days after notice
      from Landlord deliver cash to Landlord in an amount sufficient to restore
      such deposit to the full amount stated in Section 1.2. Tenant not then
      being in default, Landlord shall return the Security Deposit, or so much
      thereof as shall not have theretofore been applied in accordance with the
      terms of this Section 8.20(A) or returned to Tenant in accordance with
      Section 8.20(B), to Tenant on the expiration or earlier termination of the
      Lease Term and surrender of possession of the Premises by Tenant to
      Landlord at such time. If Landlord conveys Landlord's interest under this
      Lease, the deposit, or any part thereof not previously applied, shall be
      turned

                                      -51-

<PAGE>   52

      over by Landlord to Landlord's grantee for proper application of the
      Security Deposit in accordance with the terms of this Section 8.20 and the
      return thereof in accordance herewith.

      (B) Provided that on the applicable date (i) there exists no Event of
      Default of Tenant under the Lease and there exists no event which with the
      giving of notice or passage of time or both would constitute an Event of
      Default or (ii) if Landlord has previously applied the Security Deposit or
      any portion thereof to Landlord's damages arising from any default and
      Tenant has fully restored the amount so applied, then:

           (a)    On the last day of the twenty-fourth (24th) full calendar
                  month of the Lease Term, the Security Deposit shall be reduced
                  to $480,000.00 and within fifteen (15) days thereafter
                  Landlord shall return to Tenant such amount as shall be
                  necessary to reduce the Security Deposit to $480,000.00; and

           (b)    On the last day of the sixtieth (60th) full calendar month of
                  the Lease Term, the Security Deposit shall be further reduced
                  to $300,000.00 and within fifteen (15) days thereafter
                  Landlord shall return to Tenant such amount as shall be
                  necessary to reduce the Security Deposit to $300,000.00.

      provided, however, in no event shall the foregoing require Landlord to pay
      Tenant any amount in excess of the Security Deposit then being held by
      Landlord.

      (C) Neither the holder of any mortgage nor the lessor in any ground lease
      on property which includes the Premises shall ever be responsible to
      Tenant for the return or application of any such deposit, whether or not
      it succeeds to the position of Landlord hereunder, unless such deposit
      shall have been received in hand by such holder or ground lessor.

8.21  If Landlord shall not have received any payment or installment of rent on
      or before the date (the "Due Date") on which the same first becomes
      payable under this Lease, the amount of such payment or installment shall
      bear interest from the Due Date through and including the date such
      payment or installment is received by Landlord, at a rate equal to the
      lesser of (i) the rate announced by The First National Bank of Boston from
      time to time as its prime or base rate (or if such rate is no longer
      available, a comparable rate reasonably selected by Landlord), plus two
      percent (2%), or (ii) the maximum applicable legal rate, if any. Such
      interest shall be deemed Additional Rent and shall be paid by Tenant to
      Landlord upon demand.


                                      -52-
 
<PAGE>   53

8.22  (A) Landlord shall review the Site respecting the feasibility of
      constructing an outdoor volleyball court on the Site and shall make
      reasonable efforts to provide Tenant with an exterior area on the Site
      where a volleyball court can be constructed, given the shape and
      topography, soil conditions and existing improvements. If practicable and
      if there is sufficient space, Landlord will attempt to locate the
      volleyball court in the existing grass area on the southwest, back side of
      the Building between the Building and Hartwell Place or in the wooded area
      east of the parking lot opposite the front entrance of the Building,
      subject to the following provisions hereof. Further, to the extent
      required, Landlord shall make reasonable efforts to obtain such
      governmental permits and approvals or amendments to existing permits and
      approvals as may be necessary for the construction and operation of such a
      volleyball court (the "Governmental Approvals"). Tenant shall reasonably
      cooperate with Landlord in the foregoing. If Landlord shall be able to
      obtain the requisite Governmental Approvals and construct a volleyball
      court, the cost of obtaining the Governmental Approvals and construction
      the volleyball court shall be paid for entirely by Landlord. In no event
      shall Tenant have any obligation to pay for any portion of the cost of
      obtaining the Governmental Approvals and/or any portion of the cost of
      constructing such volleyball court. If Landlord shall not be able to
      obtain the requisite Governmental Approvals and/or if Landlord reasonably
      determines that it is not feasible to construct an outdoor volleyball
      court on the Site or if Landlord shall be unable to construct an outdoor
      volleyball court on the Site, the same shall not constitute a default of
      Landlord under this Lease, shall not give Tenant any right to terminate
      this Lease and shall not give Tenant any right to reduce, withhold, offset
      against or otherwise deduct from Annual Fixed Rent or any Additional Rent.

      (B) In addition, Landlord agrees to erect, at its sole cost and expense,
      one (1) basketball hoop at the north end of the parking lot area in a
      location mutually acceptable to Landlord and Tenant. Tenant shall have the
      right to use same and shall not interfere with the use of the parking
      areas.

8.23  This Lease shall be governed exclusively by the provisions hereof and by
      the law of the Commonwealth of Massachusetts, as the same may from time to
      time exist.



                                      -53-
 
<PAGE>   54

      EXECUTED as a sealed instrument in two or more counterparts each of which
shall be deemed to be an original.

                                         LANDLORD:


WITNESS:                                 BY: EDWARD H. LINDE, AS TRUSTEE OF
signature                                    91 HARTWELL AVENUE TRUST FOR
---------                                    HIMSELF AND CO-TRUSTEE BUT NOT
                                             INDIVIDUALLY



                                         TENANT:

                                         RESTRAC, INC.



                                         By MARTIN FAHEY
                                         Title (VICE PRESIDENT)
                                               -----------------
                                          HERETO DULY AUTHORIZED
ATTEST:
                                          BY: CYNTHA EADES
RACHAEL SHANAHAN                               TREASURER
----------------                               ---------
SECRETARY                                HERETO DULY AUTHORIZED
---------      

                                              (CORPORATE SEAL)

                                      -54-
 
<PAGE>   55

                                    EXHIBIT A
                                    ---------


      That certain parcel of land situate in Lexington in the County of
Middlesex and Commonwealth of Massachusetts, described as follows:

          SOUTHEASTERLY  by Hartwell Avenue, two hundred thirty-seven and 47/100
                         feet;

          SOUTHEASTERLY  by a curving line forming the junction of said Hartwell
                         Avenue and Hartwell Place, as shown on plan hereinafter
                         mentioned, thirty-nine and 27/100 feet;

          SOUTHWESTERLY  five hundred thirty-two and 23/100 feet, and

          SOUTHWESTERLY, SOUTHERLY and SOUTHEASTERLY one hundred ninety and
                         25/100 feet, by said Hartwell Place;

          SOUTHERLY      by lot 9 on said plan, three hundred seventy-four and
                         57/100 feet;

          SOUTHWESTERLY  three hundred sixty-seven and 65/100 feet;

          NORTHWESTERLY  thirty-one and 12/100 feet, and

          NORTHWESTERLY  again, eight hundred ninety and 63/100 feet, by land
                         now or formerly of The United States of America;

          NORTHEASTERLY  by said United States of America land and by land now
                         or formerly of John W. O'Connor et al, nine hundred
                         thirty-three and 87/100 feet.

      Said parcel is shown as lot 10 on said plan, (Plan No. 31330D).

      All of said boundaries are determined by the Court to be located as shown
on a subdivision plan, as approved by the Court, filed in the Land Registration
Office, a copy of which is filed in the Registry of Deeds for the South Registry
District of Middlesex County in Registration Book 835, Page 146, with
Certificate 141096.

      The above described land is subject to and has the benefit of the ditches
as approximately shown on said plan at date of original decree, (May 17, 1963).


                                     -55-

<PAGE>   56

      So much of the above described land as is included within the area marked
"Tennessee Gas Transmission Company Easement 30' wide" is subject to the
easements set forth in a taking by the Northeastern Gas Transmission Company,
dated July 13, 1951 and duly recorded in Book 7772, Page 162.

      The above described land is subject to an Avigation Easement set forth in
a Declaration of Taking by the United States of America dated February 12, 1954
recorded with the Middlesex South District Registry of Deeds in Book 8219, Page
421 and more particularly shown as "Avigation Easement A-130E-1" on Plan No.
31330-D (referred to above).

      The above described land is subject to an Order by the Town of Lexington
for construction of water main in Hartwell Avenue, Document No. 461902 as
affected by Certificate for Dissolving Betterments filed as Document No. 499500.

      The above described land is subject to a Grant of Easement from Wilbur C.
Nylander et al Trs. to the Town of Lexington to construct and maintain sewer in
Hartwell Place, Document No. 508567.

      The above described land is subject to a grant of Easement over 20 feet
wide drain easement (i) for the benefit of lot 9 in common with others entitled
thereto, set forth in Document 511666 and (ii) set forth in Document No. 479843
for the benefit of lot 7 shown on plan recorded with said Document No. 479843.

      The above described land is subject to a Taking of easement by the Town of
Lexington in Hartwell Place, Document No. 544200.

      The above described land is subject to and has the benefit of a Grant of
Easement and Reservation from Wilbur C. Nylander et al Trs. to the Town of
Lexington for conservation purposes, Document No. 616453.

      The above described land is subject to and has the benefit of the
following:

           A.     Order of Conditions issued by the Town of Lexington
                  Conservation Commission filed as Document No. 616456 as
                  extended by Extension Permits issued by said Conservation
                  Commission filed as Document Nos. 627154, 635069, 655552 and
                  669180.

           B.     Decision of the Town of Lexington Board of Appeals filed as
                  Document No. 616457.



                                      -56-

<PAGE>   57

           C.     Decision of the Town of Lexington Board of Appeals filed as
                  Document No. 616458.

           D.     Decision of the Town of Lexington Board of Appeals filed as
                  Document No. 616459.

           E.     Decision of the Town of Lexington Board of Appeals filed as
                  Document No. 634489.

           F.     Decision of the Town of Lexington Board of Appeals filed as
                  Document No. 646344.

           G.     Decision of the Town of Lexington Board of Appeals filed as
                  Document No. 646345.

           H.     Decision of the Town of Lexington Board of Appeals filed as
                  Document No. 646346.

      The above described land is subject to an Easement granted to Boston
Edison Company filed as Document No. 672152.

      The above described land is subject to such other easements, agreements
and matters of record, if any, insofar as in force and applicable.


                                      -57-