Filed by Cadence Design Systems, Inc. Pursuant to Rule 425
                                                Under the Securities Act of 1933
                                        Subject Company: Simplex Solutions, Inc.
                                                  Commission File No.: 000-32487


          This filing relates to a proposed merger between Cadence Design
Systems, Inc. ("Cadence") and Simplex Solutions, Inc. ("Simplex") pursuant to
the terms of an Agreement and Plan of Merger, dated as of April 24, 2002, by and
among Cadence, Simplex and Zodiac Acquisition, Inc.

          On June 4, 2002, Cadence issued the following press release regarding
the proposed merger described above:


CADENCE SATISFIES HART-SCOTT-RODINO REQUIREMENTS FOR SIMPLEX ACQUISITION

SAN JOSE, Ca., June 4, 2002 -- Cadence Design Systems, Inc. (NYSE: CDN), the
world's leading supplier of electronic design products and services, today
announced the expiration of the waiting period required under the
Hart-Scott-Rodino Antitrust Improvements Act in connection with the previously
announced proposed acquisition of Simplex Solutions, Inc. (Nasdaq: SPLX). The
Act requires parties to acquisitions valued at more than $50 million to notify
the Federal Trade Commission and the Antitrust Division of the Department of
Justice in advance of the acquisition, and to observe a waiting period, to allow
the antitrust agencies to determine whether to conduct an investigation. The
expiration of the waiting period means that the requirements of the Act have
been satisfied. Cadence expects to close the proposed merger promptly after
approval thereof by Simplex's stockholders.


ABOUT CADENCE

        Cadence is the largest supplier of electronic design technologies,
methodology services, and design services. Cadence solutions are used to
accelerate and manage the design of semiconductors, computer systems, networking
and telecommunications equipment, consumer electronics, and a variety of other
electronics-based products. With approximately 5,600 employees and 2001 revenues
of approximately $1.4 billion, Cadence has sales offices, design centers, and
research facilities around the world. The company is headquartered in San Jose,
California, and traded on the New York Stock Exchange under the symbol CDN. More
information about the company, its products and services are available at
http://www.cadence.com.


ABOUT SIMPLEX

        Simplex Solutions, Inc. provides software and services for the design
and verification of integrated circuits (ICs) to enable its communications,
computer and consumer-products customers to achieve first-time production
success and rapid delivery of complex systems-on-chip. Simplex's customers use
its products and services prior to manufacture to design and verify ICs to help
ensure that they will perform as intended, taking into account the complex
effects of




deep-submicron semiconductor physics. Simplex can be reached at 408-617-6200 or
on the web at http://www.simplex.com.

          ADDITIONAL INFORMATION ABOUT THE PROPOSED MERGER AND WHERE TO FIND IT

        On May 28, 2002, Cadence Design Systems, Inc. filed with the Securities
and Exchange Commission an amended registration statement, including a proxy
statement/prospectus, and other relevant materials in connection with the
proposed merger. The proxy statement/prospectus was mailed to the stockholders
of Simplex on or about May 29, 2002. Investors and security holders of Simplex
are urged to read the proxy statement/prospectus and the other relevant
materials because they will contain important information about Cadence, Simplex
and the proposed merger. The proxy statement/prospectus and other relevant
materials, and any other documents filed by Cadence or Simplex with the
Securities and Exchange Commission, may be obtained free of charge at the
Securities and Exchange Commission's web site at http://www.sec.gov. In
addition, investors and security holders may obtain free copies of the documents
filed with the Securities and Exchange Commission by Cadence by contacting
Cadence Investor Relations, 2655 Seely Avenue, Building 5, San Jose, California
95134, 408-943-1234. Investors and security holders may obtain free copies of
the documents filed with the Securities and Exchange Commission by Simplex by
contacting Simplex Investor Relations, 521 Almanor Avenue, Sunnyvale, California
94085, 408-617-6200. Investors and security holders are urged to read the proxy
statement/prospectus and the other relevant materials before making any voting
or investment decision with respect to the proposed merger.

        Simplex and its executive officers and directors may be deemed to be
participants in the solicitation of proxies from the stockholders of Simplex in
favor of the proposed merger. A description of the interests of the executive
officers and directors in Simplex is set forth in the proxy statement for
Simplex's 2002 Annual Meeting of Stockholders, which was filed with the
Securities and Exchange Commission on January 10, 2002. Investors and security
holders may obtain more detailed information regarding the direct and indirect
interests of the executive officers and directors in the proposed merger by
reading the proxy statement/prospectus filed with the Securities and Exchange
Commission on May 28, 2002. These documents are available free of charge at the
Securities and Exchange Commission's web site at http://www.sec.gov and from
Simplex by directing a request to Simplex Investor Relations, 521 Almanor
Avenue, Sunnyvale, California 94085, 408-617-6200.


CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

        This press release contains forward-looking statements within the
meaning of the federal securities laws, including, without limitation,
statements regarding the proposed merger between Cadence and Simplex. These
statements are subject to risks and uncertainties that could cause actual
results and events to differ materially, including, without limitation, the
following: the approval of the proposed merger by Simplex's stockholders; the
satisfaction of closing conditions, including the receipt of regulatory
approvals; and the successful integration of Simplex's employees and
technologies. A detailed discussion of other risks and uncertainties that could
cause actual results and events to differ materially from such forward-looking




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statements is included in Cadence's and Simplex's most recent filings with the
Securities and Exchange Commission. Neither Cadence nor Simplex undertakes any
obligation to update forward-looking statements to reflect events or
circumstances occurring after the date of this press release.

For more information, please contact:

Judy Erkanat
Cadence Design Systems, Inc.
408-894-2302
jerkanat@cadence.com





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