Document:

<PAGE>

                                                                   Exhibit 10.46

[LOGO] HEALTHGATE(R) DATA CORP.                    25 Corporate Drive, Suite 310
                                                   Burlington, MA 01803

                                                   TEL: (781) 685-4000
                                                   FAX: (781) 685-4040
                                                   http://www.healthgate.com

January 19, 2000

Mr. Ian Bannerman
Blackwell Science Ltd
Osney Mead
Oxford, OX2 0EL
United Kingdom

Dear Ian,

Pursuant to our conversations to date, HealthGate agrees to offer Blackwell
Science a 10% discount on the outstanding balance of the estimated total fees
for our activePress Journal Hosting and Delivery Agreement for the year 2000.
Estimated total fees for the year 2000 are US$805,500. Your fees paid to date
total US$249,125.

Therefore, Blackwell Science agrees to pay HealthGate the sum of US$556,375.00
on Friday, 21 January, 2000. This sum is an advance payment on the remaining
Software Maintenance, Content Conversion, Site Maintenance and Content Storage
fees relating to 2000, described in the activePress Journal Hosting and Delivery
Agreement, effective as of 1 January 2000.

HealthGate agrees to credit Blackwell Science with an early settlement discount
of US$55,637.50, representing 10% of the estimated total fees for Software
Maintenance, Content Conversion, Site Maintenance and Content Storage in 2000.

The balance of fees for Software Maintenance, Content Conversion, Site
Maintenance and Content Storage will be reviewed quarterly and HealthGate will
issue a statement of account to Blackwell Science effective 1 April 2000, 1 July
2000 and 1 October 2000. Any outstanding balance will be settled quarterly. If
there is an underpayment, then HealthGate will invoice any additional fees
(provided for in the activePress agreement), if any, quarterly. Any overpayment
will be credited to Blackwell Science quarterly.

All other terms and conditions from the activePress Journal Hosting and Delivery
Agreement still apply, unless waived in writing by both parties as provided for
the Agreement.

Please acknowledge the terms for early payment by signing below. We look forward
to working with you in the coming year.

Sincerely,

/s/ Rick Lawson

Rick Lawson
Vice President

For Blackwell Science Ltd.

/s/ Ian Bannerman
-------------------------------------------
Ian Bannerman
Journal Sales Director

                                                        CONFIDENTIAL INFORMATION<PAGE>

                               91 HARTWELL AVENUE
                            LEXINGTON, MASSACHUSETTS

                          LEASE DATED OCTOBER 15, 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:

<TABLE>
<CAPTION>
         <S>                                         <C>
         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
         REPRESENTATIVE:                             Stacey A. Baker

         TENANT:                                     Moldflow Pty. LTD an Australian corporation registered to do
                                                     business in Connecticut.

<PAGE>

         TENANT'S ORIGINAL                           Two Corporate Drive, Suite 232
         ADDRESS:                                    Shelton, Connecticut 06484

         TENANT'S CONSTRUCTION
         REPRESENTATIVE:                             Marc Dulude

         SPECIAL ALLOWANCE:                          As defined in Section 3.1.1

         SCHEDULED TERM
         COMMENCEMENT DATE:                          November 1, 1996

         COMMENCEMENT DATE:                          As defined in Sections 2.4 and 3.2

         OUTSIDE COMPLETION DATE:                    December 1, 1996.

         ORIGINAL TERM:                              Sixty (60) calendar months (plus the partial month, if any,
                                                     immediately following the Commencement Date), unless
                                                     extended or sooner terminated as provided in this Lease.

         EXTENSION OPTION:                           One (1) period of five (5)  years 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,

                                      -2-
<PAGE>

                                                     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:                             A portion of the first floor of the Building in accordance
                                                     with the floor plan attached hereto as Exhibit D
                                                     and incorporated herein by reference.

         NUMBER OF PARKING SPACES:                   26 spaces.

         ANNUAL FIXED RENT:                          (a) During the Original Term of this Lease at the annual
                                                     rate of $185,650.00 (being the product of (i)
                                                     $23.50 and (ii) the "Rentable Floor Area of
                                                     Tenant's Space" (hereinafter defined in this
                                                     Section 1.1).

                                                     (b) During the extension option period (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.

         RENTABLE FLOOR AREA                         7,900 square feet.
         OF TENANT'S SPACE

                                      -3-

<PAGE>

         (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.

         INITIAL MINIMUM                             $2,000,000.00 combined single limit
         LIMITS OF TENANT'S                          per occurrence on a per location basis.
         COMMERCIAL GENERAL
         LIABILITY INSURANCE:

         RECOGNIZED BROKER:                          Spaulding & Slye
                                                     125 High Street, 16th Floor
                                                     Boston, Massachusetts 02110-2701

         SECURITY DEPOSIT:                           $46,412.50

</TABLE>

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

<TABLE>
<CAPTION>
         <S>                        <C>
         EXHIBIT A                  Description of Site

         EXHIBIT A-1                Site Plan

         EXHIBIT B                  Tenant's Construction Plan

         EXHIBIT C                  Landlord's Services

         EXHIBIT D                  Floor Plan

         EXHIBIT E                  Form of Commencement Date
                                    Agreement
</TABLE>

                                      -4-

<PAGE>

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    Relocation of Tenant's Space

         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 Option

         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 and Tenant Plan Excess Costs

                                      -5-

<PAGE>

                  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

         4.2      Interruptions and Delays in Services and Repairs, etc.

         ARTICLE V-TENANT'S COVENANTS

         5.1      Payments

         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

                                      -6-

<PAGE>

         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-CASUALTY AND TAKING

         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

         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

                                      -7-

<PAGE>

         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

         8.19     Non-Subrogation

         8.20     Security Deposit

         8.21     Late Payment

         8.22     Governing Law

         8.23     Submission to Jurisdiction

                                      -8-

<PAGE>

                                   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.

2.1.1    Tenant hereby agrees with Landlord that upon the request of Landlord,
         Landlord shall have the right to relocate Tenant's Space within the
         Building one time during the Lease Term.  Upon such relocation,
         Tenant's Space shall be relocated to premises on the first, second, or
         third floor of the Building at Landlord's sole discretion.  Landlord,
         at its sole cost and expense, shall perform the partitioning of the
         relocated Tenant's Space, and shall improve, alter and finish the
         relocated Tenant's Space to substantially the same condition of the
         former Tenant's Space.  Landlord also shall pay for Tenant's reasonable
         out of pocket moving costs in relocating, including, costs to reinstall
         the telecommunication and computer lines and cabling in the relocated
         Tenant's Space.  The relocated Tenant's Space shall be complete
         (excluding punch list items and long lead items, as further defined in
         Section 3.2) before Tenant shall be required to vacate the former
         Tenant's Space.  Upon any such relocation, Tenant's Space may be
         increased or decreased by not more than one hundred fifty (150) square
         feet of Rentable Floor Area in total, and Tenant agrees to enter into
         an appropriate lease amendment reflecting the relocation of Tenant's
         Space and the adjustment to the Rentable Floor Area (as defined in
         Section 1.1 of this Lease), if any.  Further, upon adjustment to the
         Rentable Floor Area, if any, the Annual Fixed Rent defined in
         Section 1.1 of this Lease shall be at the rate defined therein but
         shall be calculated on the basis of the adjusted Rentable Floor Area
         of Tenant's 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

                                     -9-
<PAGE>

         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 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: (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 so that the same are not visible within the Premises.

2.4      Tenant shall have and hold the Premises for a period commencing on 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.

         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

                                     -10-

<PAGE>

         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 option to extend and
         at the commencement date of the 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 in excess of 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 contained
         (except for the Annual Fixed Rent which shall be adjusted during the
         option period as hereinbelow set forth) for one (1) period of five
         (5) years as hereinafter set forth.  The option period is sometimes
         herein referred to as the "Extended Term".

         (B)  If Tenant desires to exercise the option to extend the Term, then
         Tenant shall give notice to Landlord, not earlier than twelve (12)
         months nor later than nine (9) months prior to the expiration of the
         Term, hereunder of Tenant's request for Landlord's quotation of the
         annual fair market rent for the Premises as of the commencement date of
         the extension period, such quotation to be based on the use of the
         Premises in its then condition as first class office space utilizing
         properties of a similar character within the Boston West Suburban
         market (including premises within the Complex if at the time such
         quotation is requested such premises shall be available for rent)
         (hereinafter called the "Annual Market Rent"). Within thirty (30) days
         after Landlord's receipt of Tenant's notice requesting such a
         quotation, Landlord shall notify Tenant of Landlord's quotation of the
         Annual Market Rent. Within twenty (20) days after receipt by Tenant of
         Landlord's quotation of the Annual Market Rent, Tenant shall have the
         right to extend the Term by written notice to Landlord within said last
         mentioned 20-day period upon all of the same terms, conditions,
         covenants and agreements contained in this Lease, except that the
         annual fixed rent for the option period shall be equal to the Annual
         Market Rent per square foot as quoted by Landlord for the option period
         multiplied by the Rentable Floor Area of the Premises; provided,
         however, that in no event shall the annual fixed rent payable during
         the option period be less than the annual fixed rent for the last year
         of the Term of this Lease and further that the only extension option
         shall be that set forth in this Section 2.4.1. Upon the giving of such
         notice, this Lease and the Term hereof shall be extended for the option
         period, 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 fixed rent); and in such event
         all references herein to the Term or the term of this Lease shall be
         construed as referring to the Term, as so extended, unless the

                                     -11-
<PAGE>

         context clearly otherwise requires. Notwithstanding anything herein
         contained to the contrary, in no event shall the Lease Term hereof be
         extended for more than five (5) 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 the 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 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.

         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.

                                     -12-
<PAGE>

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; brokerage commissions related to the leasing of space in the
         Building; the cost of any item or service to the extent to which
         Landlord is actually reimbursed or compensated by insurance, any tenant
         or any third party; the cost of any capital expansion made to the
         Building or the Site after the date of this Lease; capital expenditures
         (except as provided hereinbelow in this Section 2.6); legal fees or
         other expenses incurred in connection with negotiating and enforcing
         leases with tenants in the Building; expenses for renovating,
         decorating or other tenant improvement work which Landlord performs in
         connection with leasing in the Building; costs incurred in performing
         work or furnishing services for any tenant (including Tenant), whether
         at such tenant's or Landlord's expense to the extent that such work or
         service is in excess of such work or service that Landlord is obligated
         to furnish to Tenant at Landlord's expense (e.g., if Landlord agrees to
         provide extra cleaning to another tenant, the cost thereof would be
         excluded since Landlord is not obligated to furnish extra cleaning to
         Tenant); the cost of any service or materials provided by any
         subsidiaries or affiliates of Landlord, to the extent such costs exceed
         the reasonable cost for such service or materials absent such
         relationship in buildings similar to the Building in the vicinity of
         the Building; interest on any debt, debt amortization or ground rent
         for any mortgage or ground lease of the Building or Site; salaries and
         other compensation paid to employees above the level of building
         manager; advertising and promotional expenses for obtaining tenants for
         the Building; fines or penalties incurred by Landlord due to violations
         by Landlord of any applicable governmental law; acquisition costs of
         sculptures, paintings or other art work for the Building, the cost of
         removal or remediation of "Hazardous Materials" (as defined in Section
         5.3) in the Building or on the Site required by "Hazardous Materials
         Laws" (as defined in Section 5.3) 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 (provided that Landlord shall prorate any such
         expenses for any person whose time is not spent solely in the operation
         of the Building or the 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

                                     -13-

<PAGE>

         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 an annual
         charge for (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 enacted after the date of
         this Lease (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 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, 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

                                     -14-
<PAGE>

         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 generally acceptable accounting practices used in the real
         estate industry 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 refund such portion of the
         overpayment as aforesaid if the Term has ended and Tenant has no
         further obligation to Landlord). At the request of Tenant, Landlord
         shall make available for Tenant's review, at Tenant's expense, and at a
         time and place reasonably determined by Landlord, the records Landlord
         used to prepare such statement. Tenant shall hold such books and
         records in confidence and not disclose the same to any other party,
         including, without limitation, any other tenant in the Building.

         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.

                                     -15-

<PAGE>

         In the event that on the average less than ninety-five percent (95%) of
         the Rentable Floor Area of the Building is leased during any calendar
         year during the Lease Term (including, without limitation, calendar
         year 1997 for purposes of calculating Base Operating Expenses),
         Landlord's Operating Expenses for such calendar year shall be
         determined by Landlord to be an amount equal to the Landlord's
         Operating Expenses which would normally be expected to have been
         charged had ninety-five percent (95%) of the Rentable Floor Area of the
         Building been leased during such calendar year.

2.7      If with respect to any full Tax Year or fraction of a Tax Year falling
         within the Term, 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 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:

                                     -16-

<PAGE>

                  (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 1996 (that
                           is, the period beginning July 1, 1995 and ending June
                           30, 1996).

                  (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.

                  (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 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

                                     -17-

<PAGE>

91 HARTWELL AVENUE
REAL ESTATE TAX ESCALATION
FOR THE PERIOD ENDING FEBRUARY 28, 1998

Tenant:  MOLDFLOW PTY, LIMITED           Square Footage:    7,900

                     JULY 1, 1997 TO FEBRUARY 28, 1998
                     ---------------------------------

Total FY 1998 Real Estate Costs:                       178,978.16

Less Tenant Real Estate Tax Base:                     (157,961.27)
                                                      -----------

Real Estate Expense Excess:                             21,016.89

Tenant's Proportionate Share: (1)                        1,359.43

Real Estate Expenses Due For The Period Occupied
July 1997 - February 1998            (243 / 243 days):   1,359.43

Less Amounts Billed:                                         0.00
                                                      -----------

TOTAL FY1998 REAL ESTATE ESCALATION DUE
LANDLORD/(TENANT)                                                      1,359.43
                                                                     ==========

(1) Tenant's Proportionate Share based on square footage of 122,135.

<PAGE>

91 HARTWELL AVENUE
REAL ESTATE TAX ESCALATION
FOR THE PERIOD ENDING JUNE 30, 1998

Tenant:  MOLDFLOW PTY, LIMITED           Square Footage:    7,900

                     MARCH 1, 1998 THROUGH JUNE 30, 1998
                     -----------------------------------

Total FY 1998 Real Estate Costs remaining:              89,489.08

Less Tenant Real Estate Tax Base:                      (78,980.63)
                                                       ----------

Real Estate Expense Excess:                             10,508.45

Tenant's Proportionate Share: (1)                          679.71

Real Estate Expenses Due For The Period Occupied
March 1998 - June 1998                  (122/122 days):    679.71

                                                                         169.93
NEW MONTHLY PAYMENT DUE LANDLORD:                                    ==========

<PAGE>

<TABLE>
<S>                                 <C>                                            <C>
MAKE PAYMENTS TO                    FISCAL YEAR 1998 REAL ESTATE TAX BILL
TOWN OF LEXINGTON                       COMMONWEALTH OF MASSACHUSETTS              BILL NUMBER  000062
COLLECTOR OF TAXES                           TOWN OF LEXINGTON
P.O. BOX 614                          OFFICE OF THE COLLECTOR OF TAXES
LEXINGTON, MASSACHUSETTS 02173
                                                                                   Based on assessment as of January 1, 1997 your
                                                                                   Real Estate Tax for the fiscal year beginning
OFFICE HOURS                                                                       July 1, 1997 and ending June 30, 1998 on the
8:30 a.m. - 4:30 p.m.                                                              Real Estate described below is as follows:
MONDAY - FRIDAY

ASSESSED OWNERS
AS OF JAN 1, 1997     85 HARTWELL AVENUE TRUST                                     Property Location 91 HARTWELL AVE
                                                                                   Map 0080          Parcel 00010C
TAX RATE              RESIDENTIAL    COMMERCIAL     INDUSTRIAL                     Reference Deed Book      951     Page 42
PER $1000                13.43          25.51          25.51                       Area 652,093.000 Sq. Ft.

                                                                                   Amount Due By:  02/02/98      72,693.15
TOTAL VALUE           10,524,000

                      85 HARTWELL AVENUE TRUST
                      8 ARLINGTON ST                                               Payment must be received in the Tax Collector's
                      BOSTON, MA 02116-3406                                        Office on or before the due date to avoid
                                                                                   penalty

                                                                                   TAXPAYER'S COPY - RETAIN FOR YOUR RECORDS

                       15501000062000726931500000000009802136

                      This form approved by the Commissioner of Revenue

                                                                             Bill No 00062

               BETTERMENTS AND LIENS                         Real Estate Tax FY97           268,467.2X
                                                             Total Betterment & Liens
                                                             Exemption / Deferral
                                                             Total Due FY97                 268,457.2X
                                                             1st Prelim: Due 08/01/97        61,540.4X
                                                             2nd Prelim: Due 11/03/97        61,540.47
                                                             3rd Quarter Tax Due 02/02/98    72,693.15
                                                             4th Quarter Tax Due 05/01/98    72,693.14
                                                             Payments                       123,030.95
                                                             Interest Due As Of 02/02/98
                                                             3rd Quarter Tax Due 02/02/98    72,693.15

  TOTAL BETTERMENTS AND LIENS                                Amount Due Now                  72,693.15

See Reverse Side For Important Information

Interest at the rate of 14% per annum will                   See reverse side of bill for important tax information.
accrue on overdue payments from the due                      If you have sold your property please forward this bill
date until payment is made.                                  to the new owner as soon as possible. Request for change
                                                             of mailing address must be sent in writing to:
* This bill reflects payments                                Board of Assessors, 1625 Massachusetts Ave,
received as of 12/11/97                                      Lexington, MA 02173

Detach Here                                                                                               Detach Here

</TABLE>

<PAGE>

                           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.

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 which in no event shall exceed the amount billed for such
         electricity by the utility company providing the same, 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.

         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

                                     -18-
<PAGE>

         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.

                                   ARTICLE III

                                  CONSTRUCTION

3.1      Landlord shall perform the work shown on Exhibit B annexed hereto. In
         addition, Landlord represents that as of the Commencement Date, the
         heating, ventilating and air conditioning system installed by Landlord
         servicing the Premises shall be in good working order and condition.
         However, 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 $86,900.00 to be applied towards the cost of the work to be
         performed by Landlord shown on Exhibit B attached hereto and the
         architect's fee in connection with the preparation of the plans
         described on Exhibit B.  Landlord shall obtain Tenant's consent
         prior to performing any work which has a cost in excess of the
         special allowance and Tenant shall pay Landlord, as Additional Rent,
         any cost of performing such work in excess of said special allowance
         within thirty (30) days after being billed therefor.  In the event
         that the cost of the work shown on Exhibit B is less than the
         special allowance, such excess shall be applied against Annual Fixed
         Rent or Additional Rent next due pursuant to this Lease.  Within one
         hundred and twenty (120) days after the Commencement Date, Landlord
         agrees to provide Tenant with a written report with respect to the
         air balance of the heating, ventilating and air conditioning system
         servicing the Premises.

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. 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 (a) 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

                                     -19-
<PAGE>

         equipment and fixtures which are not necessary to make the Premises
         tenantable for office uses and 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, provided
         that Landlord has promptly notified Tenant of such items of work
         having such characteristics after Landlord becomes aware of same
         ("long lead" items) and, (b) a certificate of occupancy, temporary or
         permanent, has been approved for issuance by applicable governmental
         authority, to the extent required by law permitting occupancy of the
         Premises by Tenant. 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 and wiring for Tenant's telephone and telecommunications
         equipment 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 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.

                                     -20-

<PAGE>

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. Except for the work shown on Exhibit B and for
         any additions or alterations which Tenant requests to remain in the
         Premises in Tenant's notice seeking Landlord's consent for the
         installation thereof (which notice shall specifically refer to this
         Section 3.3) and for which Landlord agrees in writing may remain, all
         alterations and additions shall be part of the Building unless and
         until Landlord shall specify the same for removal pursuant to Section
         5.2. 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 $2,000,000.00

                                     -21-

<PAGE>

         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.

3.3.1    Notwithstanding the terms of Section 3.3, Tenant shall have the
         right, without obtaining the prior consent of Landlord, to make
         alterations, additions or improvements to the Premises where:

                  (i)      the same are within the interior of the Premises
                           within the Building, and do not affect the exterior
                           of the Premises and the Building (including no signs
                           on windows);

                  (ii)     the same do not affect the roof, any structural
                           element of the Building, the mechanical, electrical,
                           plumbing, heating, ventilating, air-conditioning and
                           fire protection systems of the Building;

                  (iii)    the cumulative sum of the costs of said alterations,
                           additions or improvements made by Tenant during the
                           Lease Term shall not exceed $5,000.00 in cost;

                  (iv)     Tenant shall comply with the provisions of this Lease
                           and if such work increases the cost of insurance or
                           taxes or of services, Tenant shall pay for any such
                           increase in cost;

         provided, however, that Tenant shall, within fifteen (15) days after
         the making of such changes, send to Landlord plans and specifications
         describing the same in reasonable detail and provided further that
         Landlord, by notice to Tenant given at least thirty (30) days prior to
         the expiration or earlier termination of the Lease Term, may require
         Tenant to restore the Premises to its condition prior to such
         alteration, addition or improvement at the expiration or earlier
         termination of the Lease Term.

                                     -22-

<PAGE>

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 as otherwise provided in Article IV, the work
         required of Landlord pursuant to this 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 within thirty (30) days after such
         date.
<PAGE>

                                   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.

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 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.

4.1.4    To provide and install, at Landlord's expense, letters or numerals on
         (i) the entrance doors to the Premises (ii) the tenant directory in the
         lobby of the Building and (iii), at Landlord's option from time to time
         and subject to receipt of any required permits or approvals, the
         existing monument sign facing Hartwell Avenue, to identify Tenant's

                                     -23-

<PAGE>
         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.

4.1.5    Subject to escalation reimbursement in accordance with Section 2.6, to
         maintain during the Term of this Lease (a) commercial general
         liability insurance insuring Landlord with respect to the Building in
         an amount not less than $2,000,000 and insurance against loss or
         damage to the Building covered by "all risk" type insurance coverage,
         which insurance shall be in an amount at least equal the replacement
         cost of the Building.  Any and all of such insurance (i) may be
         maintained under a blanket policy affecting other premises of
         Landlord and/or its affiliated business organizations and (ii) may
         be written with deductibles as determined by Landlord. Nothing herein
         shall limit Landlord's right to maintain such other insurance as
         provided in Section 2.6 hereof.

4.2      In exercising any of its rights to enter the Premises or to repair the
         Premises or any portion of the Building, Landlord will use reasonable
         efforts not to unreasonably interfere with Tenant's business during
         such entry. Notwithstanding the foregoing sentence, 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. In the
         event that the electricity service to the Premises shall be shut down
         for more than five (5) full and consecutive business days, but only
         as a result of causes which are covered by Landlord's loss of rentals
         insurance, then, Tenant shall be entitled to an abatement of Annual
         Fixed Rent equal to the "Insurance Amount" (hereinafter defined).
         The "Insurance Amount" shall be an amount equal to the payment
         actually received by Landlord (but ONLY allocable to and on account
         of the Premises) for such shut down of electricity service to the
         Premises from Landlord's insurance carrier providing such loss of
         rents insurance less the amount of any deductible contained in such
         loss of rents insurance coverage.

         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;

                                     -24-

<PAGE>

         provided, however, that in each instance of stoppage, Landlord shall
         exercise reasonable diligence to eliminate the cause thereof. Except
         in case of emergency repairs, 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:

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 and damage from fire or other casualty only excepted, and all
         glass in windows (except glass in exterior walls unless the damage
         thereto is attributable to Tenant's negligence or misuse) 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
         and damage from fire or to other casualty only excepted, first removing
         all goods and effects of Tenant and, to the extent specified by
         Landlord by notice to Tenant given at least ten (10) days before such
         expiration or termination (unless otherwise specified by Landlord as
         set forth in Section 3.3), the wiring for Tenant's computer, telephone
         and other communication systems and equipment and all alterations and
         additions made by Tenant and all partitions, and repairing any damage
         caused by such removal and restoring the Premises and leaving 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      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

                                      -25-

<PAGE>
         machine, 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.
         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 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. Notwithstanding the foregoing,
         Tenant may use normal amounts and types of substances typically used
         for office uses, provided that Tenant uses such substances in the
         manner which they are normally used, and in compliance with all
         Hazardous Materials Laws and other applicable laws, ordinances,
         bylaws, rules and regulations, and Tenant obtains and complies with
         all permits required by Hazardous Materials Laws or any other laws,
         ordinances, bylaws, rules or regulations prior to the use or presence
         of any such substances in the Premises.

         (B) Landlord represents to Tenant that to the best of Landlord's
         actual knowledge as of the date of this Lease, based upon and except
         as provided in the Report on Oil and Hazardous Material Site
         Evaluation prepared by Dames & Moore and dated August 29, 1996, and
         the Preliminary Asbestos Survey prepared by Briggs Associates, Inc.
         and dated April 26, 1990 and Waste Shipment Manifest Numbers 008549
         and 008514 and letters from Environmental Remediation Services to
         Dec-Tam Corporation dated May 13, 1996, May 15, 1996, May 16, 1996,
         May 17, 1996 and May 20, 1996, copies of which have been provided to
         Tenant, there is no asbestos or Hazardous Materials in the Premises
         which are required to be removed or remediated by Hazardous Materials
         Laws.

                                       -26-

<PAGE>

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 general applicability to all tenants in
         the Building, 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
         normal office use, 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.

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 (i) any parent or subsidiary corporation of
         Tenant or Moldflow, Inc. (ii) to any corporation into which Tenant
         or Moldflow, Inc. may be converted or with which they may merge or be
         consolidated or (iii) to any entity which acquires substantially all
         of the assets or corporate stock of Tenant, provided that the entity
         to which this Lease is so assigned or which so sublets the Premises
         has a credit worthiness (e.g. assets on a pro forma basis using
         generally accepted accounting principles consistently applied and
         using the most recent financial statements) which in Landlord's
         reasonable determination is sufficient to perform the obligations
         of Tenant under this Lease.  Any such assignment or subletting shall
         be subject to the provisions of Section 5.6.4 and Section 5.6.6 below.

                                       -27-

<PAGE>

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 but not in part (no partial subletting being permitted other
         than as provided in Section 5.6.1), 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 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 and 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.

         In the event that Landlord shall not exercise its termination rights
         as aforesaid, or shall fail to give any or timely notice, 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,
         then for a period of one hundred twenty (120) days after the receipt
         of Tenant's notice referred to in Section 5.6.2, Tenant shall have the
         right to assign this Lease or sublet the whole (but not 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

               (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 to perform the Tenant
                        obligations as and when due or required, or

                                   -28-

<PAGE>

               (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 increase
                        Landlord's Operating Expenses beyond that which
                        Landlord now incurs for use by Tenant; (ii) be likely
                        to 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.  No partial subletting shall
         be permitted except as provided in 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
         (the whole but not part of the Premises) or assign pursuant to Tenant's
         notice, as given hereunder; provided, however, that if such assignment
         or sublease shall not be executed and delivered to Landlord within
         ninety (90) 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.

                                      -29-

<PAGE>

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. The "Assignment/Sublease Net Revenues" shall be the
         fixed rent, Additional Rent and all other charges and sums payable
         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 to the extent of the payments which such
         assignee or subtenant is obligated to make to Tenant pursuant to such
         sublease or assignment 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.

         (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

                                      -30-

<PAGE>

        by Tenant for consent to assignment or subletting in an amount not to
        exceed $1,000.00 for each request.

        (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) 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 (ii) resulting from the failure of Tenant to perform and
        discharge its covenants and obligations under this Lease; 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, 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

                                      -31-

<PAGE>

        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 and which have a rating of at
        least "A-" and are within a financial size category of not less than
        "Class VIII" in the most current Best's Key Rating Guide or such
        similar rating as may be reasonably selected by Landlord if such
        Guide is no longer published.

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, 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. Upon reasonable prior written
        or verbal notice, except in the event of an emergency, Landlord shall
        make reasonable efforts not to unreasonably interfere with Tenant's
        business during any entry to the Premises pursuant to this Section 5.9.

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;

                                      -32-

<PAGE>
        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, common areas 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. Tenant shall not be responsible for the compliance of the
        common areas with the Federal Americans with Disabilities Act (the
        "ADA") except for compliance required because of Tenants use or
        occupancy of the Premises beyond normal use of space of this kind or
        because of improvements in the Premises performed by or for Tenant.

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

                               CASUALTY AND TAKING

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.

                                     -33-

<PAGE>

        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 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 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 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 substantially the
        same condition they were in prior to the damage 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 net insurance proceeds
        are not allowed by such mortgagee or ground lessor to be applied to, or
        are insufficient for, the restoration of the Building and if Landlord
        does not otherwise elect to restore the Building, then Landlord shall
        give prompt notice to Tenant terminating this Lease, the effective date
        of which termination shall not be less than sixty (60) days after the
        date of notice of such termination.

        If such restoration is not completed within ten (10) 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 sixteen
        (16) months from the date of the fire or casualty), Tenant shall have
        the

                                      -34-

<PAGE>
        right to terminate this Lease at any time after the expiration of
        such ten-month 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.

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 Tenant has been deprived of possession of the Premises
        (or such portion thereof as may be taken). 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

                                       -35-

<PAGE>

        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 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.

                                       -36-

<PAGE>

                                   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 five (5)
                          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 on or before the date on which the same
                          become due and payable, 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,

                                      -37-

<PAGE>

                          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, 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 ten (10) days
       after the 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:

                                      -38-

<PAGE>

        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 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 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) re-let 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 commercially reasonable
        concessions or free rent to the extent that Landlord considers
        advisable or necessary to re-let the same and (ii) may make such
        alterations, repairs and decorations in the Premises as Landlord in

                                      -39-

<PAGE>

        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 in no event be liable
        in any way whatsoever for failure to re-let the Premises, or, in the
        event that the Premises are re-let, for failure to collect the rent
        under re-letting. 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.

        (f) 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

                                     -40-

<PAGE>
        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 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

                                      -41-

<PAGE>
        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 damages suffered by
        Tenant from whatever cause.

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.

                                      -42-

<PAGE>

                          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 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, if any, 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, if any, 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, if any, 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, if any, designated in Section
        1.1 hereof, Landlord shall defend the claim against Tenant with counsel
        of Landlord's selection and

                                      -43-

<PAGE>
        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, if any, 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.

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 or by recognized
        overnight courier service 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 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 with a copy to Palmer & Dodge LLP, One Beacon

                                       -44-

<PAGE>
                 Street, Boston, Massachusetts 02108, Attention: Thomas G.
                 Schnorr, Esquire (or to such other address or addresses as
                 may from time to time hereafter be designated by Tenant by
                 like notice).

        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.

        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

                                      -45-

<PAGE>
        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 holder
        subordinates its rights under such mortgage to this Lease.

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 and such failure continues beyond the
        expiration of any applicable notice, grace or cure period, 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

                                       -46-

<PAGE>
        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.

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
        (1 1/2) 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 (or required to be carried) by either party with
        respect to the Premises or property therein or occurrences thereon
        shall, if it can be so written without additional premium or with an
        additional premium which the other party agrees to pay, 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    If, in Section 1.1 hereof, a security deposit is specified, Tenant
        agrees that the same will be paid upon execution and delivery of this
        Lease, and that Landlord shall hold the same, throughout the term of
        this Lease (including any extension thereof), as security for the
        performance by Tenant of all obligations on the part of Tenant to be
        kept and performed. Landlord shall have the right from time to time
        without prejudice to any other remedy Landlord may have on account
        thereof, to apply such deposit, 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 1.1. Tenant not then being in default and having performed all
        of its obligations under this Lease, including the payment of all
        Annual Fixed Rent, Landlord shall return the deposit, or so much
        thereof as shall not have theretofore been applied in accordance with
        the terms of this Section 8.20 plus any interest earned thereon, to
        Tenant on the expiration or earlier termination of the term of this
        Lease and the surrender of possession of the Premises by Tenant to
        Landlord in the condition required by this Lease at such time. While
        Landlord holds such deposit, Landlord shall hold the same in an
        interest bearing account and shall have the right to commingle the same
        with

                                      -47

<PAGE>
        Landlord's other funds. If Landlord conveys Landlord's interest
        under this Lease, the deposit, or any part thereof not previously
        applied, shall be turned over by Landlord to Landlord's grantee, and,
        once so turned over, Tenant agrees to look solely to such grantee for
        proper application of the deposit in accordance with the terms of this
        Section 8.20, and the return thereof in accordance herewith.

        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.

8.22    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.

8.23    Tenant hereby irrevocably and unconditionally (a) submits to personal
        jurisdiction in the Commonwealth of Massachusetts over any suit, action
        or proceeding arising out of or relating to this Lease, and (b) waives
        any and all personal rights under the laws of any state to object to
        jurisdiction with respect to such suit, action or proceeding within the
        Commonwealth of Massachusetts or venue in any particular forum within
        the Commonwealth of Massachusetts. Tenant hereby appoints Suzanne
        Rogers at 91 Hartwell Avenue, Lexington, MA 02173 as its authorized
        agent for service of process and agrees that methods of service of
        process shall be, either, as determined by Landlord in Landlord's sole
        discretion, (i) as provided for under applicable law or (ii) by
        certified mail, return receipt requested to such authorized agent.
        Nothing contained herein, however, shall prevent Landlord from
        bringing any suit, action or proceeding or exercising any rights
        against Tenant, in the Commonwealth of Massachusetts, or other
        jurisdiction in which Tenant is located, all at Landlord's election,
        and against any property of Tenant, in any other state. Initiating
        such suit, action or proceeding or taking such action in any state
        shall in no event constitute a waiver of the agreement contained
        herein that the laws of the Commonwealth of Massachusetts shall govern
        the rights and obligations of Tenant and Landlord or the

                                       -48-

<PAGE>
        submission herein made by Tenant to personal jurisdiction within the
        Commonwealth of Massachusetts.

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

                                    LANDLORD:

WITNESS:                                    By /s/ Edward H. Linde
                                              --------------------------------
                                              EDWARD H. LINDE, AS TRUSTEE OF
/s/ Sue Baker                                 91 HARTWELL AVENUE TRUST FOR
------------------------------                HIMSELF AND CO-TRUSTEE BUT NOT
                                              INDIVIDUALLY

                                            TENANT:

                                            MOLDFLOW PTY. LTD

                                            By /s/ Marc Dulude
                                              --------------------------------
                                            Name   Marc Dulude
                                                ------------------------------
                                            Title  PRESIDENT (OR VICE PRESIDENT)
                                                 -----------------------------
                                                   HERETO DULY AUTHORIZED

                                            By /s/ Charles D. Yie
                                              --------------------------------
                                            Name   Charles D. Yie
                                                ------------------------------
                                            Title  CHAIRMAN
                                                 -----------------------------
                                                   (OR ASSISTANT TREASURER)
                                                   HERETO DULY AUTHORIZED

                                                              (CORPORATE SEAL)

                                     -49-

<PAGE>
                                    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).
<PAGE>

      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.

                                      -2-
<PAGE>

            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.

                                      -3-
<PAGE>

                                   EXHIBIT A-1

                                    Site Plan

                                    [GRAPHIC]

                                    SITE PLAN

                               91 HARTWELL AVENUE
                            LEXINGTON, MASSACHUSETTS
                                   [ILLEGIBLE]

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00000-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00000-of-00352.parquet"}]]