SUNNYVALE, Calif., February 28, 2001 - The United States International Trade Commission (ITC) voted yesterday to investigate whether Silicon Integrated Systems Corporation (SiS) is infringing two patents owned by United Microelectronics Corporation of Taiwan (NYSE:UMC). This is the first step toward possible U.S. Government action to exclude all SiS-manufactured integrated circuits from the U.S. market.

The ITC's decision constitutes a finding by the ITC that UMC's complaint is worthy of a full U.S. Government investigation. The decision follows a review by the ITC staff of a complaint submitted by UMC.

"UMC is extremely gratified that the U.S. Government agrees with UMC that a formal investigation into SiS's activities is warranted," said John Hsuan, UMC Chairman. "UMC intends to protect to the fullest extent of the law the intellectual property that we have spent hundreds of millions of US dollars and countless manhours of engineering and manufacturing effort over the past twenty years to develop. We believe that intellectual property is the cornerstone of our success, and know that technological prowess comes only as a result of substantial and independent effort. We cannot sit still while other companies abuse our proprietary information to launch into the business without making the investments and engineering work required to secure advanced technology legitimately. We do not believe modern industry will tolerate those who seek shortcuts to success through the misuse of intellectual property belonging to others."

The ITC's decision initiates an investigation under Section 337 of the U.S. Tariff Act. Section 337 investigations are very fast paced, and ordinarily are completed within one year. If the ITC determines that integrated circuits that infringe valid UMC patents are being imported into the United States, the ITC is likely to order that such circuits be excluded from the U.S. market and that SiS cease infringing UMC's patents. The ITC also can impose civil penalties of up to $100,000 (U.S.) per day in the event that SiS does not comply with those orders.

The ITC has assigned the case to an Administrative Law Judge who will oversee the fact-finding phase of the investigation, preside over a formal evidentiary hearing and render an initial decision. It is likely that the Judge will issue an initial decision by December 2001. Once the initial decision is made, the six ITC Commissioners will have 45 days to decide whether to conduct a review of any aspect of that determination. If the Commissioners elect not to review it, the initial determination becomes the final determination of the ITC.

The ITC is an independent, non-partisan agency of the United States government. One of its duties is to direct actions against certain unfair trade practices, including patent, trademark and copyright infringement. The ITC is headed by six Commissioners appointed by the President to nine-year terms.

A copy of UMC's Complaint is available from the ITC in Washington, D.C. and can be viewed at http://dockets.usitc.gov/eol/public.