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                                                                   Exhibit 10.51


                    NON-QUALIFIED STOCK OPTION AGREEMENT
                              FOR COMPANY EMPLOYEES
                         UNDER THE MOLDFLOW CORPORATION
                    2000 STOCK OPTION AND INCENTIVE PLAN


Name of Optionee:  _____________________________________________________________

No. of Option Share:  __________________________________________________________

Option Exercise Price per Share ($USD):  _______________________________________

Grant Date:  ___________________________________________________________________

Grant ID Number:  ______________________________________________________________

Expiration Date:  ______________________________________________________________

Pursuant to the Moldflow Corporation 2000 Stock Option and Incentive Plan (the
"Plan") as amended through the date hereof, Moldflow Corporation (the "Company")
hereby grants to the Optionee named above an option (the "Stock Option") to
purchase on or prior to the Expiration Date specified above all or part of the
number of shares of Common Stock, par value $.01 per share (the "Stock") of the
Company specified above at the Option Exercise Price per Share specified above
subject to the terms and conditions set forth herein and in the Plan.

      1. Vesting Schedule. No portion of this Stock Option may be exercised
until such portion shall have vested. This Stock Option shall be vested and
exercisable with respect to the following number of Option Shares on the dates
indicated:

<TABLE>
<CAPTION>
               Number of
          Option Shares Exercisable             Vesting Date
          -------------------------             ------------
<S>                                             <C>


</TABLE>


Once vested, this Stock Option shall continue to be exercisable at any time or
times prior to the close of business on the Expiration Date, subject to the
provisions hereof and of the Plan.

      2. Manner of Exercise.

         (a) The Optionee may exercise this Option only in the following manner:
from time to time on or prior to the Expiration Date of this Option, the
Optionee may give written notice to the Company of his or her election to
purchase some or all of the vested Option Shares purchasable at the time of such
notice. This notice shall specify the number of Option Shares to be purchased.

      Payment of the purchase price for the Option Shares may be made by one or
more of the following methods:

         (i) in cash, by certified or bank check or other instrument acceptable
 to the Administrator; (ii) in the form of shares of Stock that are not then
 subject to restrictions under any Company plan and that have been held by the
 Optionee for at least six months; (iii) by the Optionee delivering to the
 Company


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a properly executed exercise notice together with irrevocable instructions to a
broker to promptly deliver to the Company cash or a check payable and acceptable
to the Company to pay the option purchase price, provided that in the event the
Optionee chooses to pay the option purchase price as so provided, the Optionee
and the broker shall comply with such procedures and enter into such agreements
of indemnity and other agreements as the Administrator shall prescribe as a
condition of such payment procedure; or (iv) a combination of (i), (ii) and
(iii) above. Payment instruments will be received subject to collection.

      The delivery of certificates representing the Option Shares will be
contingent upon the Company's receipt from the Optionee of full payment for the
Option Shares, as set forth above and any agreement, statement or other evidence
that the Company may require to satisfy itself that the issuance of Stock to be
purchased pursuant to the exercise of Options under the Plan and any subsequent
resale of the shares of Stock will be in compliance with applicable laws and
regulations.

         (b) Certificates for shares of Stock purchased upon exercise of this
Stock Option shall be issued and delivered to the Optionee upon compliance to
the satisfaction of the Administrator with all requirements under applicable
laws or regulations in connection with such issuance and with the requirements
hereof and of the Plan. The determination of the Administrator as to such
compliance shall be final and binding on the Optionee. The Optionee shall not be
deemed to be the holder of, or to have any of the rights of a holder with
respect to, any shares of Stock subject to this Stock Option unless and until
this Stock Option shall have been exercised pursuant to the terms hereof, the
Company shall have issued and delivered the shares to the Optionee, and the
Optionee's name shall have been entered as the stockholder of record on the
books of the Company. Thereupon, the optionee shall have full voting, dividend
and other ownership rights with respect to such shares of Stock.

         (c) Notwithstanding any other provision hereof or of the Plan, no
portion of this Stock Option shall be exercisable after the Expiration Date
hereof.

      3. Termination of Employment.  If the Optionee's employment by the
Company or a Subsidiary (as defined in the Plan) is terminated, the period
within which to exercise the Option may be subject to earlier termination
as set forth below.

         (a) Termination Due to Death. If the Optionee's employment terminates
by reason of death, any portion of the Option that would otherwise vest over the
next twelve (12) months shall immediately vest in Optionee's estate or other
legal representative and become exercisable and Optionee's estate or other legal
representative shall have twelve (12) months from the date of termination, or
the remaining option term, if earlier, to exercise such Option.

         (b) Termination Due to Disability. If the Optionee's employment
terminates by reason of Disability (as defined below), any Option held by the
Optionee which would otherwise vest over the next twelve (12) months shall
immediately vest and become exercisable, and Optionee shall have twelve (12)
months from the date of termination, or the remaining Option term, if earlier,
to exercise such Option. The death of the Optionee during the twelve (12) month
period provided in this Section 3(b) shall extend such period for another twelve
(12) months from the date of death or until the Expiration Date, if earlier. The
term "Disability" shall mean incapacity as a result of physical or mental
illness pursuant to which Optionee shall have been absent from his or her duties
on a full-time basis for 180 calendar days in the aggregate in any twelve (12)
month period. In the event of a dispute, the determination of Disability will be
made by the Administrator (as defined in Section 2(a) of the Plan) in good faith
and with the advice of a physician competent in the area to which such
Disability relates.


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         (c) Termination for Cause. If the Optionee's employment terminates for
Cause (as defined below), any Option held by the Optionee shall cease to vest as
of the date of termination and the Optionee shall have thirty (30) days from the
date of termination, or the remaining Option term, if earlier, to exercise all
such vested Stock Options. The term "Cause" shall mean: (A) conduct by Optionee
constituting a material act of willful misconduct in connection with the
performance of his or her duties; (B) criminal or civil conviction of Optionee,
a plea of nolo contendere by Optionee or conduct by Optionee that would
reasonably be expected to result in material injury to the reputation of the
Company if he or she were retained in her position with the Company; (C)
continued, willful and deliberate non-performance by Optionee of his or her
duties hereunder (other than by reason of Optionee's physical or mental illness,
incapacity or disability) which has continued for more than thirty (30) days
following written notice of such non-performance from the Board; or (D) a breach
by Optionee of any of the provisions contained in Paragraphs 4 and 5 of the
Employment Agreement between the Optionee and the Company, as the same may be
amended from time to time (The "Employment Agreement").

         d) Termination by Optionee for Good Reason. If the Optionee's
employment terminates for Good Reason (as defined below), or if the Optionee's
employment is terminated by the Company without Cause (as defined in Section
3(c)), then as of the date of termination, the portion of the Option that would
otherwise vest over the next twelve (12) months shall immediately vest and
become exercisable and Optionee shall have twelve (12) months from the date of
termination, or the remaining Option term, if earlier, to exercise such Option.
The term Good Reason shall mean: (A) a substantial diminution or other
substantive adverse change, not consented to by Optionee, in the nature or scope
of Optionee's responsibilities, authorities, powers, functions or duties; (B)
any removal, during the Period of Employment, from Optionee of his or her title;
(C) an involuntary reduction in Optionee's Base Salary except for
across-the-board reductions similarly affecting all or substantially all
management employees; (D) a breach by the Company of any of its other material
obligations under the Optionee's Employment Agreement and the failure of the
Company to cure such breach within thirty (30) days after written notice thereof
by Optionee; (E) the involuntary relocation of the Company's offices at which
Optionee is principally employed or the involuntary relocation of the offices of
Optionee's primary workgroup to a location more than thirty (30) miles from such
offices, or the requirement by the Company that Optionee be based anywhere other
than the Company's offices at such location on an extended basis, except for
required travel on the Company's business to an extent substantially consistent
with Optionee's business travel obligations; or (F) the failure of the Company
to obtain the agreement from any successor to the Company to assume and agree to
perform the Employment Agreement. Terms capitalized in this Section 3 but not
defined herein shall have the meaning set forth in the Employment Agreement.

         (e) Other Termination. If the Optionee's employment terminates for any
reason other than death, Disability, Good Reason or Cause, and unless otherwise
determined by the Administrator, any Option held by the Optionee may be
exercised, to the extent exercisable on the date of termination, for a period of
three (3) months from the date of termination or until the Expiration Date, if
earlier. Any Option that is not exercisable at such time shall terminate
immediately and be of no further force or effect.

      The date of termination and the reason for termination shall be determined
pursuant to the terms of the Employment Agreement.

      4. Incorporation of Plan. Notwithstanding anything herein to the contrary,
this Stock Option shall be subject to and governed by all the terms and
conditions of the Plan. Capitalized terms in this


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Agreement shall have the meaning specified in the Plan, unless a different
meaning is specified herein.

      5. Transferability. This Agreement is personal to the Optionee, is
non-assignable and is not transferable in any manner, by operation of law or
otherwise, other than by will or the laws of descent and distribution. This
Stock Option is exercisable, during the Optionee's lifetime, only by the
Optionee, and thereafter, only by the Optionee's legal representative or
legatee.

      6. Tax Withholding. The Optionee shall, not later than the date as of
which the exercise of this Stock Option becomes a taxable event for Federal
income tax purposes, pay to the Company or make arrangements satisfactory to the
Administrator for payment of any Federal, state, and local taxes required by law
to be withheld on account of such taxable event. Subject to approval by the
Administrator, the Optionee may elect to have the minimum required tax
withholding obligation satisfied, in whole or in part, by (i) authorizing the
Company to withhold from shares of Stock to be issued, or (ii) transferring to
the Company, a number of shares of Stock owned by the Optionee with an aggregate
Fair Market Value (as of the date the withholding is effected) that would
satisfy the withholding amount due.

      7. Change of Control. Notwithstanding the foregoing, or anything in the
Plan to the contrary, in the event of a Change of Control of the Company, as
defined in the Plan, this Stock Option shall become immediately exercisable as
to all shares without regard to any vesting schedule.

      8. Miscellaneous.

         (a) Notice hereunder shall be given to the Company at its principal
place of business, and shall be given to the Optionee at the address set forth
below, or in either case at such other address as one party may subsequently
furnish to the other party in writing.

         (b) This Stock Option does not confer upon the Optionee any rights with
respect to continuance of employment by the Company or any Subsidiary.

         (c) Pursuant to Section 15 of the Plan, the Administrator may at
any time amend or cancel any outstanding portion of this Stock Option, but
no such action may be taken which adversely affects the Optionee's rights
under this Agreement without the Optionee's consent.


MOLDFLOW CORPORATION
By:  __________________________________________________

Name:
Title:

      The foregoing Agreement is hereby accepted and the terms and conditions
thereof hereby agreed to by the undersigned.

Dated:  _______________________________________________

Optionee's Signature: _________________________________


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