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                              MOLDFLOW CORPORATION

                           1997 EQUITY INCENTIVE PLAN


1.  PURPOSE

         The purpose of the Moldflow Corporation 1997 Equity Incentive Plan
(the "Plan") is to attract and retain key employees, consultants and
non-employee directors of the Company and its Affiliates, to provide an
incentive for them to achieve long-range performance goals, and to enable
them to participate in the long-term growth of the Company by granting Awards
with respect to the Company's Common Stock (the "Common Stock").

2.  ADMINISTRATION

         The Plan shall be administered by the Committee. The Committee shall
select the Participants to receive Awards and shall determine the terms and
conditions of the Awards. The Committee shall have authority to adopt, alter
and repeal such administrative rules, guidelines and practices governing the
operation of the Plan as it shall from time to time consider advisable, and
to interpret the provisions of the Plan. The Committee's decisions shall be
final and binding. To the extent permitted by applicable law, the Committee
may delegate to one or more executive officers of the Company the power to
make Awards to Participants who are not Reporting Persons or Covered
Employees and all determinations under the Plan with respect thereto,
provided that the Committee shall fix the maximum amount of such Awards for
all such Participants and a maximum for any one Participant.

3.  ELIGIBILITY

         All employees, consultants and non-employee directors of the Company
or any Affiliate capable of contributing significantly to the successful
performance of the Company, other than a person who has irrevocably elected
not to be eligible, are eligible to be Participants in the Plan. Incentive
Stock Options may be granted only to persons eligible to receive such Options
under the Code.

4.  STOCK AVAILABLE FOR AWARDS

         (a) AMOUNT. Subject to adjustment under subsection (b), Awards may
be made under the Plan for up to 3,689,180 shares of Common Stock. If any
Award expires or is terminated unexercised or is forfeited or settled in a
manner that results in fewer shares outstanding than were awarded, the shares
subject to such Award, to the extent of such expiration, termination,
forfeiture or decrease, shall again be available for award under the Plan.
Common Stock issued through the assumption or substitution of outstanding
grants from an acquired company shall not reduce the shares available for
Awards under the Plan. Shares issued under the Plan may consist in whole or
in part of authorized but unissued shares or treasury shares.

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         (b) ADJUSTMENT. In the event that the Committee determines that any
stock dividend, extraordinary cash dividend, recapitalization,
reorganization, merger, consolidation, split-up, spin-off, combination,
exchange of shares or other transaction affects the Common Stock such that an
adjustment is required in order to preserve the benefits intended to be
provided by the Plan, then the Committee (subject in the case of Incentive
Stock Options to any limitation required under the Code) shall equitably
adjust any or all of (i) the number and kind of shares in respect of which
Awards may be made under the Plan, (ii) the number and kind of shares subject
to outstanding Awards and (iii) the exercise price with respect to any of the
foregoing, and if considered appropriate, the Committee may make provision
for a cash payment with respect to an outstanding Award, provided that the
number of shares subject to any Award shall always be a whole number.

         (c) LIMIT ON INDIVIDUAL GRANTS. Subject to adjustment under
subsection (b), the maximum number of shares of Common Stock subject to Stock
Options and SARs that may be granted to any Participant in the aggregate in
any calendar year will not exceed 3,689,180 shares.

5.  STOCK OPTIONS

         (a) GRANT OF OPTIONS. Subject to the provisions of the Plan, the
Committee may grant options ("Options") to purchase shares of Common Stock
(i) complying with the requirements of Section 422 of the Code or any
successor provision and any regulations thereunder ("Incentive Stock
Options") and (ii) not intended to comply with such requirements
("Nonstatutory Stock Options"). The Committee shall determine the number of
shares subject to each Option and the exercise price therefor, which in the
case of Incentive Stock Options shall not be less than 100% of the Fair
Market Value of the Common Stock on the date of grant, provided that a
Nonstatutory Stock Option granted to a new employee, consultant or
non-employee director within 90 days of the date of employment may have a
lower exercise price so long as it is not less than 100% of Fair Market Value
on the date of employment. No Incentive Stock Option may be granted hereunder
more than ten years after the effective date of the Plan.

         (b) TERMS AND CONDITIONS. Each Option shall be exercisable at such
times and subject to such terms and conditions as the Committee may specify
in the applicable grant or thereafter. The Committee may impose such
conditions with respect to the exercise of Options, including conditions
relating to applicable federal or state securities laws, as it considers
necessary or advisable.

         (c) PAYMENT. Payment for shares to be delivered pursuant to any
exercise of an Option may be made in whole or in part in cash or, to the
extent permitted by the Committee at or after the grant of the Option, by
delivery of a note or other commitment satisfactory to the Committee or
shares of Common Stock owned by the optionee, including Restricted Stock, or
by retaining shares otherwise issuable pursuant to the Option, in each case
valued at their Fair Market Value on the date of delivery or retention, or
such other lawful consideration as the Committee may determine.

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6.  STOCK EQUIVALENTS

         (a) GRANT OF STOCK EQUIVALENTS. Subject to the provisions of the
Plan, the Committee may grant rights to receive payment from the Company
based in whole or in part on the value of the Common Stock. The Committee
shall determine at the time of grant or thereafter whether Stock Equivalents
are settled in cash, Common Stock or other securities of the Company, Awards
or other property.

         (b) STOCK APPRECIATION RIGHTS. Stock Equivalents may include rights
to receive any excess in value of shares of Common Stock over the exercise
price ("Stock Appreciation Rights" or "SARs") which may be granted in tandem
with an Option (at or after the award of the Option), or alone and unrelated
to an Option. SARs in tandem with an Option shall terminate to the extent
that the related Option is exercised, and the related Option shall terminate
to the extent that the tandem SARs are exercised. The Committee shall fix the
exercise price of each SAR or specify the manner in which the price shall be
determined and may define the manner of determining the excess in value of
the shares of Common Stock. An SAR granted in tandem with an Option shall
have an exercise price not less than the exercise price of the related
Option. An SAR granted alone and unrelated to an Option may not have an
exercise price less than 100% of the Fair Market Value of the Common Stock on
the date of the grant, provided that such an SAR granted to a new employee,
consultant or non-employee director within 90 days of the date of employment
may have a lower exercise price so long as it is not less than 100% of Fair
Market Value on the date of employment.

7.  STOCK GRANTS

         (a) GRANT OF STOCK. Subject to the provisions of the Plan, the
Committee may grant shares of Common Stock upon such terms and conditions as
the Committee determines. Stock Grants may be issued for no cash
consideration, such minimum consideration as may be required by applicable
law or such other consideration as the Committee may determine.

         (b) RESTRICTED STOCK. Stock Grants may include shares subject to
forfeiture ("Restricted Stock"). The Committee will determine the duration of
the period (the "Restricted Period") during which, and the conditions under
which, the shares may be forfeited to the Company and the other terms and
conditions of such Awards. Shares of Restricted Stock may not be sold,
assigned, transferred, pledged or otherwise encumbered, except as permitted
by the Committee, during the Restricted Period. Shares of Restricted Stock
shall be evidenced in such manner as the Committee may determine. Any
certificates issued in respect of shares of Restricted Stock shall be
registered in the name of the Participant and unless otherwise determined by
the Committee, deposited by the Participant, together with a stock power
endorsed in blank, with the Company. At the expiration of the Restricted
Period, the Company shall deliver such certificates to the Participant or if
the Participant has died, to the Participant's Designated Beneficiary.

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8.  GENERAL PROVISIONS APPLICABLE TO AWARDS

         (a) REPORTING PERSON LIMITATIONS. Notwithstanding any other
provision of the Plan, to the extent required to qualify for the exemption
provided by Rule 16b-3 under the Exchange Act, Awards made to a Reporting
Person shall not be transferable by such person other than by will or the
laws of descent and distribution and are exercisable during such person's
lifetime only by such person or by such person's guardian or legal
representative. If then permitted by Rule 16b-3, such Awards, unless
Incentive Stock Options, may also be made transferable pursuant to a
Qualified Domestic Relations Order as defined in the Code or Title I of the
Employee Retirement Income Security Act or the rules thereunder.

         (b) DOCUMENTATION. Each Award under the Plan shall be evidenced by a
writing delivered to the Participant specifying the terms and conditions
thereof and containing such other terms and conditions not inconsistent with
the provisions of the Plan as the Committee considers necessary or advisable
to achieve the purposes of the Plan or to comply with applicable tax and
regulatory laws and accounting principles.

         (c) COMMITTEE DISCRETION. Each type of Award may be made alone, in
addition to or in relation to any other Award. The terms of each type of
Award need not be identical, and the Committee need not treat Participants
uniformly. Except as otherwise provided by the Plan or a particular Award,
any determination with respect to an Award may be made by the Committee at
the time of grant or at any time thereafter.

         (d) DIVIDENDS AND CASH AWARDS. In the discretion of the Committee,
any Award under the Plan may provide the Participant with (i) dividends or
dividend equivalents payable currently or deferred with or without interest
and (ii) cash payments in lieu of or in addition to an Award.

         (e) TERMINATION OF EMPLOYMENT. The Committee shall determine the
effect on an Award of the disability, death, retirement or other termination
of employment or service on the Board of Directors of a Participant and the
extent to which, and the period during which, the Participant's legal
representative, guardian or Designated Beneficiary may receive payment of an
Award or exercise rights thereunder.

         (f) CHANGE IN CONTROL. In order to preserve a Participant's rights
under an Award in the event of a change in control of the Company (as defined
by the Committee), the Committee in its discretion may, at the time an Award
is made or at any time thereafter, take one or more of the following actions:
(i) provide for the acceleration of any time period relating to the exercise
or payment of the Award, (ii) provide for payment to the Participant of cash
or other property with a Fair Market Value equal to the amount that would
have been received upon the exercise or payment of the Award had the Award
been exercised or paid upon the change in control, (iii) adjust the terms of
the Award in a manner determined by the Committee to reflect the change in
control, (iv) cause the Award to be assumed, or new rights substituted
therefor, by another entity, or (v) make such other provision as the
Committee may consider equitable to Participants and in the best interests of
the Company.

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         (g) LOANS. The Committee may authorize the making of loans or cash
payments to Participants in connection with the grant or exercise any Award
under the Plan, which loans may be secured by any security, including Common
Stock, underlying or related to such Award (provided that the loan shall not
exceed the Fair Market Value of the security subject to such Award), and
which may be forgiven upon such terms and conditions as the Committee may
establish at the time of such loan or at any time thereafter.

         (h) WITHHOLDING TAXES. The Participant shall pay to the Company, or
make provision satisfactory to the Committee for payment of, any taxes
required by law to be withheld in respect of Awards under the Plan no later
than the date of the event creating the tax liability. In the Committee's
discretion, such tax obligations may be paid in whole or in part in shares of
Common Stock, including shares retained from the Award creating the tax
obligation, valued at their Fair Market Value on the date of delivery. The
Company and its Affiliates may, to the extent permitted by law, deduct any
such tax obligations from any payment of any kind otherwise due to the
Participant.

         (i) FOREIGN NATIONALS. Awards may be made to Participants who are
foreign nationals or employed outside the United States on such terms and
conditions different from those specified in the Plan as the Committee
considers necessary or advisable to achieve the purposes of the Plan or to
comply with applicable laws.

         (j) AMENDMENT OF AWARD. The Committee may amend, modify or terminate
any outstanding Award, including substituting therefor another Award of the
same or a different type, changing the date of exercise or realization and
converting an Incentive Stock Option to a Nonstatutory Stock Option, provided
that the Participant's consent to such action shall be required unless the
Committee determines that the action, taking into account any related action,
would not materially and adversely affect the Participant.

9.  CERTAIN DEFINITIONS

         "Affiliate" means any business entity in which the Company owns
directly or indirectly 50% or more of the total voting power or has a
significant financial interest as determined by the Committee.

         "Award" means any Stock Option, Stock Grant or Stock Equivalent
granted under the Plan.

         "Board" means the Board of Directors of the Company.

         "Code" means the Internal Revenue Code of 1986, as amended from time
to time, or any successor law.

         "Committee" means one or more committees each comprised of not less
than two members of the Board appointed by the Board to administer the Plan
or a specified portion thereof. Unless otherwise determined by the Board, if
a Committee is authorized to grant

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Awards to a Reporting Person or a Covered Employee, each member shall be a
"non-employee director" or the equivalent within the meaning of applicable
Rule 16b-3 under the Exchange Act or an "outside director" within the meaning
of Section 162(m) of the Code, respectively.

         "Common Stock" or "Stock" means the Common Stock, $0.01 par value,
of the Company.

         "Company" means Moldflow Corporation, a Delaware corporation.

         "Covered Employee" means a "covered employee" within the meaning of
Section 162(m) of the Code.

         "Designated Beneficiary" means the beneficiary designated by a
Participant, in a manner determined by the Committee, to receive amounts due
or exercise rights of the Participant in the event of the Participant's
death. In the absence of an effective designation by a Participant,
"Designated Beneficiary" means the Participant's estate.

         "Exchange Act" means the Securities Exchange Act of 1934, as amended
from time to time, or any successor law.

         "Fair Market Value" means, with respect to Common Stock or any other
property, the fair market value of such property as determined by the
Committee in good faith or in the manner established by the Committee from
time to time.

         "Participant" means a person selected by the Committee to receive an
Award under the Plan.

         "Reporting Person" means a person subject to Section 16 of the
Exchange Act.

10.  MISCELLANEOUS

         (a) NO RIGHT TO EMPLOYMENT. No person shall have any claim or right
to be granted an Award. Neither the Plan nor any Award hereunder shall be
deemed to give any employee the right to continued employment or to limit the
right of the Company to discharge any employee at any time.

         (b) NO RIGHTS AS STOCKHOLDER. Subject to the provisions of the
applicable Award, no Participant or Designated Beneficiary shall have any
rights as a stockholder with respect to any shares of Common Stock to be
distributed under the Plan until he or she becomes the holder thereof. A
Participant to whom Common Stock is awarded shall be considered the holder of
the Stock at the time of the Award except as otherwise provided in the
applicable Award.

         (c) EFFECTIVE DATE. Subject to the approval of the stockholders of
the Company, the Plan shall be effective on August 14, 1997.

         (d) AMENDMENT OF PLAN. The Board may amend, suspend or terminate the
Plan or

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any portion thereof at any time, subject to such stockholder approval as the
Board determines to be necessary or advisable to comply with any tax or
regulatory requirement.

         (e) GOVERNING LAW. The provisions of the Plan shall be governed by
and interpreted in accordance with the laws of the state of Delaware.

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THIS PLAN WAS INITIALLY APPROVED BY THE BOARD OF DIRECTORS ON AUGUST 14, 1997.

REVISED OCTOBER 20, 1998, PER BOARD CONSENT. REVISED APRIL 22, 1999 PER BOARD
VOTE, RATIFIED BY A CONSENT OF ALL STOCKHOLDERS EFFECTIVE APRIL 23, 1999.









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