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                                                                  EXHIBIT 10.26

                              SEPARATION AGREEMENT
                           GENERAL RELEASE AND WAIVER

                  SEPARATION AGREEMENT and GENERAL RELEASE and WAIVER (this
"Agreement") made as of December 3, 2001 (the "Execution Date"), by and among
Gerald Chien Kuo Hsu (the "Employee"), Synopsys, Inc. ("Synopsys"), and Avant!
Corporation, (the "Employer," together with Synopsys and the Employee, the
"Parties").

                  WHEREAS, the Employer engaged the Employee to be an employee
of the Employer;

                  WHEREAS, the Employee and the Employer are parties to an
Employment Agreement, dated August 24, 2000 (the "August 24, 2000 Agreement"),
and a Modification Agreement, dated July 25, 2001, (together with the August 24,
2000 Agreement, the "Employment Agreement"); and

                  WHEREAS, the Parties wish to confirm the termination of the
Employee's employment with the Employer and set forth their agreement as to the
manner in which the Employee's employment with the Employer will be closed out.

                  NOW, THEREFORE, in consideration of the mutual covenants set
forth herein and for other good and valuable consideration, receipt of which is
hereby acknowledged, the Parties agree as follows:

                  1. Confirmation of Termination. The Parties hereby now
acknowledge and confirm that the Employee's employment with the Employer and its
affiliates (as defined in Rule 12b-2 under the Securities Exchange Act of 1934,
as amended (the "Affiliates" and the "Exchange Act") shall terminate as of the
Effective Time (as defined in the Agreement and Plan of Merger by and among
Synopsys, Maple Forest Acquisition LLC and the Employer, dated as of December 3,
2001 (the "Merger Agreement")) (the "Termination Date"). The Employee hereby
resigns, effective as of the Termination Date, all positions, titles, duties,
authorities and responsibilities with, arising out of or relating to his
employment with the Employer or its Affiliates, including all positions on the
board of directors (or any committee thereof) of the Employer or its Affiliates.
The Parties acknowledge and agree that neither Party shall be required to
perform any of its obligations under this Agreement, and the releases contained
in Section 3 of this Agreement shall not become effective, until the Effective
Time under the Merger Agreement shall have occurred, and that this Agreement
shall terminate automatically, and neither Party shall have any liability
hereunder, if the Merger Agreement shall have been terminated as provided
therein. Notwithstanding the preceding sentence, the Employee agrees that he
shall not, at any time between the Execution Date and either the Effective Time
or a termination of the Merger Agreement, exercise any of his rights to
terminate the Employment Agreement under Section 8(a)(i) or 8(c) of the August
24, 2000 Agreement; provided, however, that if during such time period any
ground shall arise on which the Employee would otherwise be entitled to
terminate the Employment Agreement under Section 8(c) of the Employment
Agreement, the Employee's right to terminate the Employment Agreement on such
ground shall be preserved until 10 days after the end of such time period, even
if such ground for termination shall have ceased to exist prior to the end of
such period.
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                  2.       Termination Payment.

                  (a) On the Termination Date, and subject to Section 6 herein,
the Employer shall pay the Employee the sum of (i) thirty million, six hundred
thousand dollars ($30,600,000), (ii) the amount due pursuant to Section 9(b)(iv)
of the August 24, 2000 Agreement (determined by reference to the closing price
of the Employer's Common Stock on the day before the date of the Effective Time,
and (iii) any unpaid salary, bonus (for services through December 31, 2001 only,
but this parenthetical reference shall not affect the Employee's right under the
Employment Agreement to a bonus for any subsequent year in the event that this
Agreement is terminated as provided in the third sentence of Section 1), expense
reimbursement, previously deferred compensation or vacation pay to which the
Employee may be entitled up to the Termination Date pursuant to the August 24,
2000 Agreement.

                  (b) The amount set forth in Section 2(a) shall be referred to
herein as the "Termination Payment." The Termination Payment shall be reduced by
any required tax withholdings. The Termination Payment shall not be taken into
account as compensation under, and no service credit shall be given after the
Termination Date for purposes of determining the benefits payable under, any
benefit plan, program, agreement or arrangement of the Employer or its
Affiliates. The Employee acknowledges that, except for the Termination Payment
and payments provided under Section 13 of the August 24, 2000 Agreement (and the
other indemnification provisions identified in the final sentence of the first
paragraph of Section 3(b)(i) below), he is not entitled to any payment in the
nature of severance or termination pay from the Employer or any of its
Affiliates and is not entitled to any other amount, payment or benefit, of any
nature whatsoever, from the Employer or any of its Affiliates, including,
without limitation, under any employee benefit plan, program or arrangement of
the Employer or its Affiliates (other than any vested benefit under the
Employer's 401(k) plan) or under the Employment Agreement.

                  3.       General Releases and Waivers

                  (a) General Release and Waiver by Synopsys, Inc., et al
("RELEASE")

                      (i) SYNOPSYS, INC. ("RELEASOR"), on behalf of itself, its
           corporate parents, subsidiaries and Affiliates, including without
           limitation the Employer and its subsidiaries and Affiliates, and its
           directors, managing directors, officers, control persons,
           stockholders, employees, agents, attorneys, administrators,
           successors and assigns (collectively, "RELEASOR"), for good and
           valuable consideration received from the Employee, releases and
           discharges the Employee and his heirs, executors, agents, attorneys,
           administrators, successors and assigns (collectively, "RELEASEE")
           from any claim or cause of action, accounts, agreements, bonds,
           bills, covenants, contracts, controversies, claims, damages, demands,
           debts, dues, extents, executions, judgments, liabilities,
           obligations, promises, predicate acts, reckonings, specialties,
           suits, sums of money, trespasses and variances, including without
           limitation court costs and attorneys fees, in law or in equity, which
           RELEASOR has as of the Execution Date against RELEASEE that are based
           on actions or omissions of RELEASEE occurring prior to the Execution
           Date which, as of the Execution Date (A) are known to RELEASOR, or
           (B) have been disclosed in a publicly available report or other


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          document filed on or before the Execution Date with the U.S.
          Securities and Exchange Commission by or on behalf of RELEASEE or the
          Employer, or (C) have been disclosed to RELEASOR by RELEASEE or the
          Employer on or before the Execution Date, the information described in
          (A), (B) and (C) being hereinafter referred to as the "Disclosed
          Facts" (collectively, the "RELEASED MATTERS"). For the purposes of
          this paragraph, a claim against RELEASEE shall be deemed to have
          existed as of the Execution Date if such claim is based upon actions
          or omissions of RELEASEE that occurred or began prior to the Execution
          Date, even if (i) RELEASOR's right to damages or equitable relief on
          such claim had not matured as of the Execution Date; or (2) RELEASOR
          became entitled to additional or different legal or equitable relief
          on such claim after the Execution Date as a result of a continuation
          of the same actions or omissions or the effects thereof, and/or the
          passage of time, after the Execution Date, and such claim shall be
          deemed to include the right to any such additional or different
          relief. "RELEASED MATTERS" do not include any claim that RELEASOR may
          now or hereafter have against the Employee's son, John Hsu, to the
          extent such a claim is based on actions or omissions of John Hsu
          rather than actions or omissions of the Employee.

                      (ii) THE PARTIES ACKNOWLEDGE THAT THEY ARE FAMILIAR WITH
          SECTION 1542 OF THE CIVIL CODE OF THE STATE OF CALIFORNIA, WHICH
          PROVIDES AS FOLLOWS:

                      "A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE
          CREDITOR DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF
          EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY
          AFFECTED HIS SETTLEMENT WITH THE DEBTOR."

                      RELEASOR EXPRESSLY WAIVES AND RELINQUISHES ANY RIGHT OR
           BENEFIT WHICH IT HAS OR MAY HAVE UNDER SECTION 1542 OF THE CIVIL CODE
           OF THE STATE OF CALIFORNIA, OR ANY OTHER STATUTE OR LEGAL PRINCIPLE
           WITH SIMILAR EFFECT WITH RESPECT TO CLAIMS BASED ON OR ARISING FROM
           THE DISCLOSED FACTS, BUT RELEASOR DOES NOT WAIVE OR RELINQUISH ANY
           SUCH RIGHT OR BENEFIT WITH RESPECT TO CLAIMS THAT ARE NOT BASED ON OR
           DO NOT ARISE FROM THE DISCLOSED FACTS.

                      RELEASEE acknowledges that he is aware that, after
           executing this RELEASE, RELEASOR or its attorneys or agents may
           discover facts in addition to or different from the Disclosed Facts,
           and that it is the intention of RELEASOR and RELEASEE not to settle
           and release any claim or cause of action, accounts, agreements,
           bonds, bills, covenants, contracts, controversies, claims, damages,
           demands, debts, dues, extents, executions, judgments, liabilities,
           obligations, promises, predicate acts, reckonings, specialties,
           suits, sums of money, trespasses and variances, including without
           limitation court costs and attorneys fees, in law or in equity, which
           may exist on the basis of facts other than the Disclosed Facts.


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<PAGE>
                      (iii) The RELEASED MATTERS do not include any claims for
          the breach by RELEASEE or any person or entity acting on his behalf of
          the obligations arising under this Agreement.

                      (iv) Nothing in this Release is intended to, or shall be
          construed or claimed to be, a license in favor of RELEASEE with
          respect to any property of RELEASOR, the Employer, or any other person
          or entity.

                      (v) This RELEASE may not be modified or amended except by
          an instrument in writing signed by the RELEASOR and the RELEASEE.

                  (b) General Release and Waiver by the Employee ("EMPLOYEE
RELEASE").

                      (i) The Employee on behalf of himself, his heirs,
           executors, agents, attorneys, administrators, successors and assigns
           (collectively, "EMPLOYEE RELEASOR"), for good and valuable
           consideration received from the Employer or its Affiliates, hereby
           releases and discharges the Employer, Synopsys and their respective
           subsidiaries and Affiliates and their respective present and former
           directors, managing directors, officers, control persons,
           stockholders, employees, agents, attorneys, administrators,
           successors and assigns (collectively, "SYNOPSYS RELEASEE"), from any
           claim or cause of action, accounts, agreements, bonds, bills,
           covenants, contracts, controversies, claims, damages, demands, debts,
           dues, extents, executions, judgments, liabilities, obligations,
           promises, predicate acts, reckonings, specialties, suits, sums of
           money, trespasses and variances, including without limitation court
           costs and attorneys fees, in law or in equity, which EMPLOYEE
           RELEASOR has as of the Execution Date against SYNOPSYS RELEASEE that
           are based on actions or omissions of SYNOPSYS RELEASEE occurring
           prior to the Execution Date which, as of the Execution Date (A) are
           known to EMPLOYEE RELEASOR; or (B) have been disclosed in a publicly
           available report or other document filed on or before the Execution
           Date with the U.S. Securities and Exchange Commission by or on behalf
           of EMPLOYEE RELEASEE, Synopsys or the Employer, or (C) have been
           disclosed to EMPLOYEE RELEASOR by SYNOPSYS RELEASEE or the Employer
           on or before the Execution Date, the information described in (A),
           (B) and (C) being hereinafter referred to as the "Facts Disclosed to
           EMPLOYEE RELEASOR" (collectively, the "EMPLOYEE RELEASED MATTERS"),
           including, without limitation, under the Americans with Disabilities
           Act of 1990, the Family and Medical Leave Act of 1993, Title VII of
           the United States Civil Rights Act of 1964, 42 U.S.C. Section 1981,
           the California Fair Employment and Housing Act, California's Unruh
           Civil Rights Act, Section 51 of the California Civil Code, the
           California Labor Code, the California Family Rights Act, or any other
           Federal, state, or local law and any workers' compensation or
           disability claims under any such laws. This EMPLOYEE RELEASE relates
           to claims arising from or during Employee's employment relationship
           with the Employer or its Affiliates or as a result of the termination
           of such relationship. The EMPLOYEE RELEASOR further agrees that the
           EMPLOYEE RELEASOR will not file or permit to be filed on EMPLOYEE
           RELEASOR'S behalf any such claim. Notwithstanding the preceding
           sentence or any other provision of this Agreement, this EMPLOYEE
           RELEASE is not intended to interfere with EMPLOYEE RELEASOR's right
           to file a charge with the


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          Equal Employment Opportunity Commission in connection with any claim
          EMPLOYEE RELEASOR believes EMPLOYEE RELEASOR may have against SYNOPSYS
          RELEASEE. However, by executing this Agreement, EMPLOYEE RELEASOR
          hereby waives the right to recover in any proceeding EMPLOYEE RELEASOR
          may bring before the Equal Employment Opportunity Commission or any
          state human rights commission or in any proceeding brought by the
          Equal Employment Opportunity Commission or any state human rights
          commission on EMPLOYEE RELEASOR'S behalf. This EMPLOYEE RELEASE is for
          any relief, no matter how denominated, including, but not limited to,
          injunctive relief, wages, back pay, front pay, compensatory damages,
          or punitive damages. This EMPLOYEE RELEASE shall not apply to any
          obligation of the Employer pursuant to this Agreement, Section 13 of
          the August 24, 2000 Agreement or any other right to indemnification
          that the Employee may now or hereafter have under any other
          indemnification agreement with the Employer, statute, or the
          Employer's certificate of incorporation or bylaws.

                      Without limiting the breadth of the preceding paragraph,
           "EMPLOYEE RELEASED MATTERS" shall include any claim, not based on
           Facts Disclosed to EMPLOYEE RELEASOR, that EMPLOYEE RELEASOR may now
           or hereafter have against SYNOPSYS RELEASEE based on any transaction
           described in Item 404 of Regulation S-K under the Exchange Act
           involving or relating to the Employer or any of its "subsidiaries"
           (as such term is defined in Rule 12b-2 under the Exchange Act) (i) to
           which the Employee or any member of his "immediate family" (as such
           term is defined in Rule 16a-1 under the Exchange Act) is presently a
           party, or (ii) in which the Employee presently has any "pecuniary
           interest" (as such term is defined in the next sentence). For
           purposes of this paragraph, the term "pecuniary interest" means the
           opportunity, directly or indirectly, to profit or share in any profit
           derived from a transaction, including any "indirect pecuniary
           interest" (as such term is defined in Rule 16a-1 under the Exchange
           Act) and, for purposes of clarification, determined without regard to
           whether the transaction involves any securities of the Employer or
           any subsidiary. The Employee shall be liable to the Employer for any
           damages resulting to the Employer from a transaction to which the
           first sentence of this paragraph applies, but only to the extent of
           the Employee's pecuniary interest in such transaction and only if the
           facts concerning such transaction are not Disclosed Facts.

                      "EMPLOYEE RELEASED MATTERS" does not include any claim
           that any heir of the Employee may now or hereafter have against
           SYNOPSYS RELEASEE, except for any such claim that is based solely on
           the status of such person as an heir of the Employee.

                      (ii) THE PARTIES ACKNOWLEDGE THAT THEY ARE FAMILIAR WITH
          SECTION 1542 OF THE CIVIL CODE OF THE STATE OF CALIFORNIA, WHICH
          PROVIDES AS FOLLOWS:

                      "A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE
          CREDITOR DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF
          EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY
          AFFECTED HIS SETTLEMENT WITH THE DEBTOR."


                                       5
<PAGE>
                      EMPLOYEE RELEASOR, HAVING READ AND UNDERSTOOD SECTION 1542
           AND BEEN ADVISED BY HIS OWN COUNSEL CONCERNING SECTION 1542 AND THE
           LEGAL EFFECT OF A WAIVER THEREOF, EXPRESSLY WAIVES AND RELINQUISHES
           ANY RIGHT OR BENEFIT WHICH HE HAS OR MAY HAVE UNDER SECTION 1542 OF
           THE CIVIL CODE OF THE STATE OF CALIFORNIA, OR ANY OTHER STATUTE OR
           LEGAL PRINCIPLE WITH SIMILAR EFFECT WITH RESPECT TO CLAIMS BASED ON
           OR ARISING FROM FACTS DISCLOSED TO EMPLOYEE RELEASOR, BUT EMPLOYEE
           RELEASOR DOES NOT WAIVE OR RELINQUISH ANY SUCH RIGHT OR BENEFIT WITH
           RESPECT TO CLAIMS THAT ARE NOT BASED ON OR DO NOT ARISE FROM FACTS
           DISCLOSED TO EMPLOYEE RELEASOR.

                       SYNOPSYS RELEASEE acknowledges that it is aware that,
           after executing this EMPLOYEE RELEASE, EMPLOYEE RELEASOR or his
           attorneys or agents may discover facts in addition to or different
           from the Facts Disclosed to EMPLOYEE RELEASOR, and that it is the
           intention of EMPLOYEE RELEASOR and SYNOPSYS RELEASEE not to settle
           and release any claim or cause of action, accounts, agreements,
           bonds, bills, covenants, contracts, controversies, claims, damages,
           demands, debts, dues, extents, executions, judgments, liabilities,
           obligations, promises, predicate acts, reckonings, specialties,
           suits, sums of money, trespasses and variances, including without
           limitation court costs and attorneys fees, in law or in equity, which
           may exist on the basis of facts other than the Facts Disclosed to
           EMPLOYEE RELEASOR.

                      (iii) This EMPLOYEE RELEASE may not be modified or amended
          except by an instrument in writing signed by the EMPLOYEE RELEASOR and
          the SYNOPSYS RELEASEE.

                      (iv) The EMPLOYEE RELEASED MATTERS do not include any
          claims for the breach by any person other than the Employee of
          obligations arising under this Agreement.

                  4.       Restrictive Covenants

                  The Employee hereby agrees and acknowledges that the Employee
shall be bound by and shall comply with the restrictive covenants provided in
Sections 16 and 17 of the August 24, 2000 Agreement and that such restrictive
covenants are hereby made a part of this Agreement as if specifically restated
herein, subject in each case to all of the terms and conditions of such Sections
16 and 17 except as expressly provided below in this section, provided that, the
Employee hereby agrees that, (a) with respect to Section 17 of the August 24,
2000 Agreement, (i) he shall not engage in any of the restricted activities
listed under Section 17 of the August 24, 2000 Agreement for a period of four
years from the Termination Date, (ii) clause 17(a)(i) shall be amended to read
as follows:

                  (i) Become an officer, director, partner, associate, employee,
         owner, agent, creditor, independent contractor, co-venturer or
         otherwise, or be interested in or associated with any other
         corporation, firm or business engaged, in any geographical area


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<PAGE>
         in which the Employer, Synopsys or their respective subsidiaries and
         Affiliates (the "Synopsys Group") is then engaged, in making or selling
         one or more products competitive with a product or products then being
         made or sold by the Synopsys Group in the EDA industry, which products
         made or sold by the Synopsys Group accounted for at least 1% of the
         annual sales of either the Corporation or Synopsys (including in each
         case their respective subsidiaries and affiliates) during the four
         fiscal quarter period ending with the last fiscal quarter completed
         prior to the Termination Date;

                   and (iii) clause 17(a)(iv) shall be amended by replacing the
word "executive" in line three thereof with the word "employee", and by adding
the following at the end of such clause 17(a)(iv): ", nor to any solicitation of
Yvonne Liu (commencing six months after the Termination Date), Kevin Liu, David
Huang, D.J. Ma, Maggie Chen, C.S. Kuo or any relative of the Employee; and (b)
the obligation not to disclose confidential information, as described under
Section 16 of the August 24, 2000 Agreement, shall not terminate on the first
anniversary of the Termination Date with respect to trade secrets related to the
Employer's technology or financial information, or to the pricing or other
material terms or conditions of agreements between the Employer and any of its
customers, but shall instead continue until the fourth anniversary of the
Termination Date with respect to such trade secrets. The Employee agrees and
acknowledges that the Proprietary Information and Inventions Agreement executed
by him continues in full force and effect in accordance with its terms, except
to the extent that Sections 4(a) and 4(b) of this Agreement expressly state a
more limited scope or duration of the Employee's obligations not to disclose the
Employer's confidential information or to compete with the Employer or the
Synopsys Group. The restrictions imposed on the Employee's activities under
Section 17 of the August 24, 2000 Agreement, as incorporated by reference in and
amended by this Agreement, shall not be interpreted to restrict any activities
of the Employee that are not materially related to the EDA industry, nor to the
Employee's donation of any money, property or services to any educational,
scientific or religious organization as defined in Section 501(c)(3) of the
Internal Revenue Code, as amended (or any such organization that would fall
within such definition if the entire world were part of the United States).

                  The Employee hereby agrees that it is impossible to measure in
money the damages which will accrue to the Employer, Synopsys or their
respective subsidiaries and Affiliates (the "Synopsys Group") by reason of a
failure by the Employee to perform any of his obligations under the restrictive
covenants. Accordingly, notwithstanding Section 11 of this Agreement, if the
Synopsys Group institutes any action or proceeding to enforce the provisions
hereof, to the extent permitted by applicable law, the Employee hereby waives
the claim or defense that the Synopsys Group has an adequate remedy at law, and
the Employee shall not urge in any such action or proceeding the claim or
defense that any such remedy at law exists.

                  5. [intentionally omitted]

                  6. Certain Forfeitures in Event of Breach

                  The Employee acknowledges and agrees that, notwithstanding any
other provision of this Agreement, in the event the Employee breaches any of his
obligations under Section 4(a) of this Agreement relating to Section 17 of the
August 24, 2000 Agreement, the Employee will forfeit his right to receive the
Termination Payment under Section 2 of this Agreement to the


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<PAGE>
extent not theretofore paid to him as of the date of such breach and, if already
made as of the time of breach, the Employee agrees that he will reimburse the
Employer, immediately, for the amount of such payment. The preceding sentence
states the Employer's exclusive monetary remedy for such a breach. In no event
shall the Employee's aggregate liability for any breach or breaches of any
obligations under this Agreement exceed the amount of the Termination Payment
received by him.

                  7. Cooperation in Certain Litigation Matters

                  From the Termination Date through the earliest to occur of the
fifth anniversary thereof, the Employee's death or the Employee's disability, or
such other time as the Parties may mutually agree, the Employee agrees to
cooperate with the Synopsys Group as the Synopsys Group may from time to time
request in connection with certain litigation matters relating to the Employer,
not to exceed an aggregate of 10 business days in any month, unless the Parties
otherwise agree, provided that the nature and timing of the cooperation
requested is reasonable. To the extent such cooperation can reasonably be
provided by telephone, the time spent providing such cooperation by telephone
shall be aggregated on the basis that eight hours constitutes one business day.
Such cooperation shall relate to litigation pending as of the Termination Date
involving the Employer or its Affiliates and any other litigation relating to
events or circumstances existing or occurring during the Employee's period of
employment as to which the Synopsys Group requests the Employee's cooperation:

                                    (A) cooperation in regard to such litigation
                provided, however, notwithstanding the occurrence of the fifth
                anniversary of the Termination Date the Employee's agreement to
                cooperate respecting such litigation shall continue for the
                duration of such litigation and the Employee shall be provided
                reasonable additional compensation agreed to by the Parties for
                such cooperation as the Employee may provide;

                                    (B) if requested by the Synopsys Group, such
                cooperation shall include, without limitation, (1) responding
                promptly to requests for information and documents in the
                Employee's possession concerning matters pertinent to any of the
                foregoing, (2) making himself available as a witness and
                testifying at trial, depositions, hearings or other proceedings,
                as well as being available for adequate preparation for such
                testimony; and (3) participating at times in interviews and
                meetings with representatives of the Synopsys Group,
                representatives of governments or regulatory authorities, or
                others designated by the Synopsys Group;

                                    (C) unless prohibited by applicable law or
                any rule of any applicable regulatory authority, the Employee
                further agrees to notify the Employer and Synopsys promptly of
                any request made to the Employee by any party to any such
                litigations for information or assistance with respect to such
                litigations, and the substance of the Employee's response to
                such request. The Employee shall also provide the Employer and
                Synopsys with a copy of such request and response, if in
                writing;


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<PAGE>
                                    (D) the Employee and the Synopsys Group will
                each use good faith best efforts to reconcile and accommodate
                any conflicts in scheduling such cooperation described above,
                the Synopsys Group taking into account previously scheduled
                vacation or personal plans of the Employee and the Employee
                taking into account the Synopsys Group's need to comply with
                judicial or other schedules; and

                                    (E) in respect of all cooperation provided
                by the Employee hereunder, the Employer shall pay all of the
                Employee's reasonable out-of-pocket expenses in connection
                therewith promptly upon the Employee's presentation to the
                Employer of an invoice specifying the amount and purpose of the
                expense.

                  8.       No Admission

                  This Agreement does not constitute an admission of liability
or wrongdoing of any kind by any member of the Synopsys Group, including the
Employer or its Affiliates.

                  9.       Indemnification

                  The Parties hereby agree and acknowledge that they shall be
bound by Section 13 of the August 24, 2000 Agreement. The Employee shall not
unreasonably withhold his consent to the settlement of any litigation or other
proceeding as to which the Employee is indemnified under such Section 13,
provided that such settlement will not require payment of any material amount by
the Employee or otherwise result in a material detriment to the Employee.

                  10.      Heirs and Assigns

                  The terms of this Agreement shall be binding on the Parties
hereto and their respective successors and assigns.

                  11.      Arbitration

                  The Parties hereby agree and acknowledge that they shall be
bound by Section 14 of the August 24, 2000 Agreement.

                  12.      General Provisions

                  (a)      Notice

                  Any notice or other communication required or permitted under
this Agreement shall be effective only if it is in writing and shall be deemed
to be given when delivered personally or four days after it is mailed by
registered or certified mail, postage prepaid, return receipt requested or one
day after it is sent by a reputable overnight courier service and, in each case,
addressed as follows (or if it is sent through any other method agreed upon by
the Parties):

                  If to the Employee:

                  Gerald C. Hsu
                  5295 Blackhawk Drive


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<PAGE>
                  Danville, California 94506

                  With a copy to:

                  Eric A. Brill, Esq.
                  3535 Clay Street
                  San Francisco, CA 94118

                  If to the Employer or Synopsys:

                  Synopsys, Inc.
                  700 East Middlefield Road
                  Mountain View, CA 94043
                  Attention: General Counsel

                  Or to such other address as any party hereto may designate by
notice to the other.

                  (b)      Integration

                  This Agreement constitutes the entire understanding of the
Synopsys Group and the Employee with respect to the subject matter hereof and
supersedes all prior understandings, written or oral, including the Employment
Agreement (except for Sections 13, 14, 16 and 17 of the August 24, 2000
Agreement, which shall remain in effect as provided herein). The terms of this
Agreement may be changed, modified or discharged only by an instrument in
writing signed by the Parties hereto. A failure of the Synopsys Group or the
Employee to insist on strict compliance with any provision of this Agreement
shall not be deemed a waiver of such provision or any other provision hereof. In
the event that any provision of this Agreement is determined to be so broad as
to be unenforceable, such provision shall be interpreted to be only so broad as
is enforceable.

                  (c)      Choice of Law

                  THIS AGREEMENT SHALL BE CONSTRUED, ENFORCED AND INTERPRETED IN
ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF DELAWARE, WITHOUT
REFERENCE TO PRINCIPLES OF CONFLICT OF LAWS.

                  (d)      Construction of Agreement

                  The Parties hereto acknowledge and agree that each Party has
reviewed and negotiated the terms and provisions of this Agreement and has had
the opportunity to contribute to its revision. Accordingly, the rule of
construction to the effect that ambiguities are resolved against the drafting
party shall not be employed in the interpretation of this Agreement. Rather, the
terms of this Agreement shall be construed fairly as to both Parties hereto and
not in favor or against either Party.


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<PAGE>
                  (e)      Counterparts

                  This Agreement may be executed in any number of counterparts
and by different Parties on separate counterparts, each of which counterpart,
when so executed and delivered, shall be deemed to be an original and all of
which counterparts, taken together, shall constitute but one and the same
Agreement.

                  13.      Acknowledgement

                  The Employee acknowledges that, by the Employee's free and
voluntary act of signing below, the Employee has had an opportunity to consult
with attorneys and other advisers of his choosing regarding this Agreement, has
reviewed all of the terms of this Agreement and fully understands all of its
provisions, including, without limitation, the general release and waiver set
forth therein, and agrees to all of the terms of this Agreement and intends to
be legally bound thereby.

                                        Avant! Corporation

                                        /s/ Sheng-Chun Lo
                                        -------------------------------
                                        Name:  Sheng-Chun Lo
                                        Title: President

                                        Synopsys, Inc.


                                        /s/ Aart de Geus
                                        -------------------------------
                                        Name:  Aart de Geus
                                        Title: Chief Executive Officer

                                        /s/ Gerald Chien Kuo Hsu
                                        -------------------------------
                                        Gerald Chien Kuo Hsu


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