TAIPEI, R.O.C.—(BUSINESS WIRE)—Nov. 9, 2004— United Microelectronics Corporation (NYSE: UMC; TAIEX: 2303), (UMC) today reported unaudited net sales for the month of October 2004.

Revenues for October 2004

    Period          2004        2003     Y/Y Change  Y/Y (%)   M/M (%)
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    October      10,064,217   7,665,349   2,398,868   +31.29%   -15.2%
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   Jan.-Oct.     99,147,283  68,808,222  30,339,061   +44.09%     N/A
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(*) All figures in thousands of New Taiwan Dollars (NT$), except for percentages.

Additional information about UMC is available on the web at http://www.umc.com.

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