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                                                                    Exhibit 10.3

                                 FIRST AMENDMENT
                                       TO
                             PRODUCT LEASE AGREEMENT

               THIS FIRST AMENDMENT TO PRODUCT LEASE AGREEMENT (the "FIRST
AMENDMENT") is made as of the 20th day of November, 2001, between AVANT! JAPAN
CORPORATION (the "COMPANY"), with its principal place of business at Nittochi
Shin-yurigaoka Building, 5F, 1-5-2 Kamiasao Asao-ku, Kawasaki-shi, Kanagawa
215-0021, Japan and MAINGATE ELECTRONICS INC. (the "DISTRIBUTOR"), with its
principal place of business at KAKiYA Building, 3F, 2-7-17 Shinyokohama,
Kohoku-ku, Yokohama-shi, Kanagawa 222-0033, Japan.

                               W I T N E S S E T H

        WHEREAS, the Company and the Distributor are parties to that certain
Product Lease Agreement dated as of October 1, 2000 (the "AGREEMENT"); and

        WHEREAS, pursuant to the Agreement, the Distributor is entitled to
certain compensation upon the termination of the Agreement; and

        WHEREAS, the Company and the Distributor now desire to amend the
Agreement to, among other things, disallow any compensation payable to the
Distributor upon termination of the Agreement.

        NOW, THEREFORE, in consideration of the mutual covenants herein
contained and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto mutually
promise, covenant, undertake and agree as follows:

        1. Consequence of Termination. In consideration of a payment of
US$1,000.00 by the Company to the Distributor, the receipt of which is hereby
acknowledged, Section 19.4 of the Agreement shall be amended and restated in its
entirety as follows:

               "19.4 Upon termination, neither the Distributor nor any of its
affiliates shall be entitled to any compensation or fee of any sort whatsoever
from the Company or any of its affiliates."

        2. Certification by the Distributor. The Distributor certifies that:

            a.  this Agreement, as amended hereby, and the Distribution
                Agreement, dated as of October 1, 2000, between the parties (the
                "DISTRIBUTION AGREEMENT"), are the only agreements currently in
                effect between the Company or any of its affiliates on the one
                hand, and the Distributor or any of its affiliates on the other
                hand, with respect to distribution of the Company's products or
                services; and

            b.  this Agreement, as amended hereby, and the Distribution
                Agreement represent the entire agreement between the Company or
                any of its affiliates on the one hand,



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                and the Distributor or any of its affiliates on the other hand,
                with respect to distribution of the Company's products or
                services; and

            c.  there are no amendments, modifications, or supplements to this
                Agreement, whether oral or written, other than this First
                Amendment; and

            d.  the Company is not in any respect in default under the
                Agreement, as hereby amended; and

            e.  notwithstanding the provisions of Section 20.7 of the Agreement,
                the Distributor consents and agrees to the (A) disclosure of any
                and all terms of the Agreement and this First Amendment (i) in
                the public reports, registration statements and other filings of
                Avant! Corporation, a Delaware corporation ("PARENT"), that have
                been filed or in the future may be filed with the US Securities
                and Exchange Commission (the "SEC"), and (ii) as may be required
                by applicable law, and (B) public filing of the Agreement and
                this First Amendment with the SEC by Parent.

        3. Release. The Distributor, for itself, its legal successors and
assigns, partners, limited partners, constituent entities, affiliated and
related companies, officers, directors, stockholders, principals, servants,
employees, agents and representatives, and each of them, do hereby absolutely,
fully and forever release, relieve, waive, relinquish, absolve, acquit and
discharge the Company and the Company's respective legal successors,
predecessors, and assigns, partners, limited partners, constituent entities,
affiliated and related companies, officers, directors, stockholders, principals,
servants, employees, attorneys, agents and representatives of and from any and
all manner of claims, demands, promises, cause or causes of action, action or
actions, suits, debts, liabilities, obligations, costs, expenses, sums of money,
controversies, damages, accounts, reckonings, and liens of every kind or nature
whatsoever, whether mature, contingent, direct, derivative, subrogated,
personal, assigned, discovered, undiscovered or otherwise (hereinafter called
"CLAIMS"), which they have or may have or have had, owned, or held at any time
by reason of any matter, cause or thing whatsoever from the beginning of time to
the date hereof in any way arising out of or relating to (i) any termination
fee, termination payment or similar award due upon termination of the Agreement
arising under or in connection with the Agreement, any prior agreement between
the Company or its affiliates on the one hand, and the Distributor or its
affiliates on the other hand, or the distribution of the Company and its
affiliates' products and services by the Distributor or otherwise or (ii) this
First Amendment. Distributor hereby represents, warrants, and acknowledges to
the Company that it has received independent legal advice from its attorneys
regarding the advisability of executing this First Amendment and giving the
release provided for herein, and that it has been advised by their attorneys
concerning and is familiar with the provisions of Section 1542 of the Civil Code
of the State of California and any similar provision under Japanese law, 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.


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Distributor, being aware of Section 1542 and such similar provisions, hereby
expressly waives and relinquishes any rights or benefits it has or may have
thereunder in connection with the release provided herein, as well as under any
other California or federal or foreign statute or common law principle of
similar effect. The Distributor acknowledges that it is aware that it or its
attorneys may hereafter discover facts different from or in addition to the
facts which it or its attorneys now know or believe to be true with respect to
the subject matter of this First Amendment, but that it is their intention
hereby to settle fully, finally, absolutely and forever any and all claims,
disputes and differences which do now exist or heretofore have existed between
the Distributor and its affiliates on the one hand, and Company and its
affiliates on the other, in any way arising out of or relating to (i) any
termination fee, termination payment or similar award due upon termination of
the Agreement arising under or in connection with the Agreement, any prior
agreement between the Company or its affiliates on the one hand, and the
Distributor or its affiliates on the other hand, or the distribution of the
Company and its affiliates' products and services by the Distributor or
otherwise or (ii) this First Amendment. In furtherance of this intention, the
release herein given shall be and remain in effect as a full and complete
release notwithstanding discovery of any such different or additional facts.

        4. Miscellaneous.

               4.1 Amendment and Waiver. Except as otherwise expressly provided
herein, any provision of this First Amendment may be amended and the observance
of any provision of this First Amendment may be waived (either generally or any
particular instance and either retroactively or prospectively) only with the
written consent of the parties.

               4.2 Governing Law and Legal Actions. This First Amendment shall
be governed by and construed under the laws of Japan without regard to conflicts
of laws or provisions thereof and without regard to the United Nations
Convention on Contracts for the International Sale of Goods. Both parties
consent to the non-exclusive jurisdiction of the Japanese courts and agree that
process may be served in the manner provided for giving of notices or otherwise
as allowed by Japanese law. In any action or proceeding to enforce rights under
this Agreement, the prevailing party shall be entitled to recover costs and
attorneys' fees.

               4.3 Severability. If any provision of this First Amendment is
held by a court of competent jurisdiction to be illegal, invalid, or
unenforceable, that provision shall be limited or eliminated to the minimum
extent necessary so that this First Amendment shall otherwise remain in full
force and effect and enforceable.

               4.4 Entire Agreement. This First Amendment supersedes all
proposals, oral or written, all negotiations, conversations, discussions, or
prior agreements between or among parties relating to the subject matter of this
First Amendment and all past dealing or industry custom.

               4.5 Assignment. The Distributor may not assign this First
Amendment or the rights thereunder without the prior consent of the Company. The
Company may assign this First Amendment by giving notice to the Distributor.


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               4.6 Counterparts. This First Amendment may be executed in
counterparts, each of which shall be deemed an original, but both of which
together shall constitute one and the same instrument.

                            [SIGNATURE PAGE FOLLOWS]




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               IN WITNESS WHEREOF, the parties hereto have executed this First
Amendment, all of the day and year first above written.

                                         AVANT! JAPAN CORPORATION

                                         By  /s/ Howard Ko
                                           ------------------------------------
                                         Name: Howard Ko

                                         Title: Executive Operating Officer

                                         MAINGATE ELECTRONICS INC.

                                         By  /s/ Moriyuki Chimura
                                           ------------------------------------
                                         Name: Moriyuki Chimura

                                         Title: President




         (SIGNATURE PAGE TO FIRST AMENDMENT TO PRODUCT LEASE AGREEMENT)
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