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                                                                  EXHIBIT 10.4.1


                               NASSDA CORPORATION

                        FORM OF DIRECTOR OPTION AGREEMENT

     NASSDA Corporation (the "Company"), has granted to ___________________ (the
"Optionee"), an option to purchase a total of [__________ (____)] shares of the
Company's Common Stock (the "Optioned Stock"), at the price determined as
provided herein, and in all respects subject to the terms, definitions and
provisions of the Company's 2001 Director Option Plan (the "Plan") adopted by
the Company which is incorporated herein by reference. The terms defined in the
Plan shall have the same defined meanings herein.

     1.  Nature of the Option. This Option is a nonstatutory option and is not
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intended to qualify for any special tax benefits to the Optionee.

     2.  Exercise Price. The exercise price is $_______ for each share of Common
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Stock.

     3.  Exercise of Option. This Option shall be exercisable during its term in
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accordance with the provisions of Section 8 of the Plan as follows:

         (i)  Right to Exercise.
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              (a)  (FIRST GRANT) This Option shall become with respect to 1/3 of
the Optioned Stock one year after the date of grant and 13/6/th/ of the Optioned
Stock each month thereafter, so that one hundred percent (100%) of the Optioned
Stock shall be exercisable three years after the date of grant; provided,
however, that in no event shall any Option be exercisable prior to the date the
stockholders of the Company approve the Plan.

     OR       (a)  (SUBSEQUENT GRANTS) This Option shall become exercisable in
installments cumulatively with respect to 1/24th of the Optioned Stock each
month following the one year anniversary of the date of grant, so that one
hundred percent (100%) of the Optioned Stock shall be exercisable three years
after the date of grant; provided, however, that in no event shall any Option be
exercisable prior to the date the stockholders of the Company approve the Plan.

              (b)  This Option may not be exercised for a fraction of a share.

              (c)  In the event of Optionee's death, disability or other
termination of service as a Director, the exercisability of the Option is
governed by Section 8 of the Plan.

         (ii) Method of Exercise. This Option shall be exercisable by written
              ------------------
notice which shall state the election to exercise the Option and the number of
Shares in respect of which the Option is being exercised. Such written notice,
in the form attached hereto as Exhibit A, shall be signed by the Optionee and
                               ---------
shall be delivered in person or by certified mail to the Secretary of the
Company. The written notice shall be accompanied by payment of the exercise
price.

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     4.  Method of Payment. Payment of the exercise price shall be by any of the
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following, or a combination thereof, at the election of the Optionee:

         (i)   cash;

         (ii)  check; or

         (iii) surrender of other shares which (x) in the case of Shares
acquired upon exercise of an Option, have been owned by the Optionee for more
than six (6) months on the date of surrender, and (y) have a Fair Market Value
on the date of surrender equal to the aggregate exercise price of the Shares as
to which said Option shall be exercised; or

         (iv)  delivery of a properly executed exercise notice together with
such other documentation as the Company and the broker, if applicable, shall
require to effect an exercise of the Option and delivery to the Company of the
sale or loan proceeds required to pay the exercise price.

     5.  Restrictions on Exercise. This Option may not be exercised if the
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issuance of such Shares upon such exercise or the method of payment of
consideration for such shares would constitute a violation of any applicable
federal or state securities or other law or regulations, or if such issuance
would not comply with the requirements of any stock exchange upon which the
Shares may then be listed. As a condition to the exercise of this Option, the
Company may require Optionee to make any representation and warranty to the
Company as may be required by any applicable law or regulation.

     6.  Non-Transferability of Option. This Option may not be transferred in
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any manner otherwise than by will or by the laws of descent or distribution and
may be exercised during the lifetime of Optionee only by the Optionee. The terms
of this Option shall be binding upon the executors, administrators, heirs,
successors and assigns of the Optionee.

     7.  Term of Option. This Option may not be exercised more than ten (10)
         --------------
years from the date of grant of this Option, and may be exercised during such
period only in accordance with the Plan and the terms of this Option.

     8.  Taxation Upon Exercise of Option. Optionee understands that, upon
         --------------------------------
exercise of this Option, he or she will recognize income for tax purposes in an
amount equal to the excess of the then Fair Market Value of the Shares purchased
over the exercise price paid for such Shares. Since the Optionee is subject to
Section 16(b) of the Securities Exchange Act of 1934, as amended, under certain
limited circumstances the measurement and timing of such income (and the
commencement of any capital gain holding period) may be deferred, and the
Optionee is advised to contact a tax advisor concerning the application of
Section 83 in general and the availability a Section 83(b) election in
particular in connection with the exercise of the Option. Upon a resale of such
Shares by the Optionee, any difference between the sale price and the Fair
Market Value of the Shares on the

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date of exercise of the Option, to the extent not included in income as
described above, will be treated as capital gain or loss.

        DATE OF GRANT: ______________

                                                NASSDA CORPORATION,
                                                a Delaware corporation


                                                By: ____________________________

        Optionee acknowledges receipt of a copy of the Plan, a copy of which is
attached hereto, and represents that he or she is familiar with the terms and
provisions thereof, and hereby accepts this Option subject to all of the terms
and provisions thereof. Optionee hereby agrees to accept as binding, conclusive
and final all decisions or interpretations of the Board upon any questions
arising under the Plan.

        Dated: _________________

                                                ___________________________
                                                Optionee

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                                    EXHIBIT A

                         DIRECTOR OPTION EXERCISE NOTICE

NASSDA Corporation
2975 Scott Boulevard, Suite 110
Santa Clara, CA 95054


Attention:  Corporate Secretary

     1.  Exercise of Option. The undersigned ("Optionee") hereby elects to
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exercise Optionee's option to purchase ______ shares of the Common Stock (the
"Shares") of NASSDA Corporation (the "Company") under and pursuant to the
Company's 2001 Director Option Plan and the Director Option Agreement dated
_______________ (the "Agreement").

     2.  Representations of Optionee. Optionee acknowledges that Optionee has
         ---------------------------
received, read and understood the Agreement.

     3.  Federal Restrictions on Transfer. Optionee understands that the Shares
         --------------------------------
must be held indefinitely unless they are registered under the Securities Act of
1933, as amended (the "1933 Act"), or unless an exemption from such registration
is available, and that the certificate(s) representing the Shares may bear a
legend to that effect. Optionee understands that the Company is under no
obligation to register the Shares and that an exemption may not be available or
may not permit Optionee to transfer Shares in the amounts or at the times
proposed by Optionee.

     4.  Tax Consequences. Optionee understands that Optionee may suffer adverse
         ----------------
tax consequences as a result of Optionee's purchase or disposition of the
Shares. Optionee represents that Optionee has consulted with any tax
consultant(s) Optionee deems advisable in connection with the purchase or
disposition of the Shares and that Optionee is not relying on the Company for
any tax advice.

     5.  Delivery of Payment. Optionee herewith delivers to the Company the
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aggregate purchase price for the Shares that Optionee has elected to purchase
and has made provision for the payment of any federal or state withholding taxes
required to be paid or withheld by the Company.

     6.  Entire Agreement. The Agreement is incorporated herein by reference.
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This Exercise Notice and the Agreement constitute the entire agreement of the
parties and supersede in their entirety all prior undertakings and agreements of
the Company and Optionee with respect to the

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subject matter hereof. This Exercise Notice and the Agreement are governed by
California law except for that body of law pertaining to conflict of laws.

          Submitted by:                   Accepted by:

          OPTIONEE:                       NASSDA CORPORATION



          By: ________________________    By: __________________________________

                                          Its:__________________________________


          Address:


          Dated: _____________________    Dated: _________________________

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