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                                                                Exhibit 10.43


                           LOAN MODIFICATION AGREEMENT

       This Loan Modification Agreement is entered into as of June 26, 2002, by
and between Moldflow Corporation (the "Borrower") and Silicon Valley Bank, a
California-chartered bank doing business in Massachusetts under the name
"Silicon Valley East" ("Bank").

1. DESCRIPTION OF EXISTING OBLIGATIONS: Among other Obligations which may be
owing by Borrower to Bank, Borrower is indebted to Bank pursuant to, among other
documents, a Loan Agreement, dated November 13, 2001, as may be amended from
time to time, (the "Loan Agreement"). The Loan Agreement provides for, among
other things, a Committed Line in the original principal amount of Five Million
Dollars ($5,000,000). Defined terms used but not otherwise defined herein shall
have the same meanings as set forth in the Loan Agreement.

Hereinafter, all indebtedness owing by Borrower to Bank shall be referred to as
the "Obligations."

2. Hereinafter, all other documents evidencing or securing the Obligations shall
be referred to as the "Existing Loan Documents".

3. DESCRIPTION OF CHANGE IN TERMS.

       A. MODIFICATION(S) TO LOAN AGREEMENT.


            1.   The defined term of "Profitability" under Section 5.7 entitled
                 "Financial Covenants" is hereby amended in part to read as
                 follows:

                   Borrower will have a minimum net profit of $1 for each fiscal
                   quarter except Borrower may suffer losses not to exceed
                   $500,000 for the quarters ending June 30, 2002 and September
                   30, 2002. For calculation purposes, Profitability shall be
                   defined as Borrower's net income after taxes, but prior to
                   depreciation, amortization and non-cash restructuring
                   expenses. For purposes of this covenant, restructuring
                   expenses shall be deducted from net profit when cash payments
                   are made in respect of such expenses.

4. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever
necessary to reflect the changes described above.

5. NO DEFENSES OF BORROWER. Borrower agrees that, as of this date, it has no
defenses against paying the Obligations.

6. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the
existing Obligations, Bank is relying upon Borrower's representations,
warranties, and agreements, as set forth in the Existing Loan Documents. Except
as expressly modified pursuant to this Loan Modification Agreement, the terms of
the Existing Loan Documents remain unchanged and in full force and effect.
Bank's agreement to modifications to the existing Obligations pursuant to this
Loan Modification Agreement in no way shall obligate Bank to make any future
modifications to the Obligations. Nothing in this Loan Modification Agreement
shall constitute a satisfaction of the Obligations. It is the intention of Bank
and Borrower to retain as liable parties all makers and endorsers of Existing
Loan Documents, unless the party is expressly released by Bank in writing.
Unless expressly released herein, no maker, endorser, or guarantor will be
released by virtue of this Loan Modification Agreement. The terms of this
Paragraph apply not only to this Loan Modification Agreement, but also to all
subsequent loan modification agreements.

7. JURISDICTION/VENUE. Borrower accepts for itself and in connection with its
properties, unconditionally, the non-exclusive jurisdiction of any state or
federal court of competent jurisdiction in the Commonwealth of Massachusetts in
any action, suit, or proceeding of any kind against it which arises out of or by
reason of this Loan Modification Agreement; provided, however, that if for any
reason Bank cannot avail itself of the courts of the Commonwealth of
Massachusetts, then venue shall lie in Santa Clara County, California.


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8. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective
only when it shall have been executed by Borrower and Bank (provided, however,
in no event shall this Loan Modification Agreement become effective until signed
by an officer of Bank in California).


       This Loan Modification Agreement is executed as of the date first written
above.


BORROWER:                                BANK:

MOLDFLOW CORPORATION                     SILICON VALLEY BANK, doing business
                                         as SILICON VALLEY EAST


By: /s/ Suzanne E. Rogers                By: /s/ Mark Gallagher
  -------------------------------           -------------------------------
Name: Suzanne E. Rogers                  Name: Mark Gallagher
     ----------------------------             -----------------------------
Title: Vice President                    Title: Vice President
      ---------------------------              ----------------------------



                                         SILICON VALLEY BANK


                                         By: /s/ Maggie Garcia
                                            ---------------------------------
                                         Name: Maggie Garcia
                                              -------------------------------
                                         Title: Assistant Vice Preseident
                                               ------------------------------
                                              (Signed at Santa Clara County, CA)



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