TAIPEI, R.O.C.—(BUSINESS WIRE)—Dec. 7, 2004— United Microelectronics Corporation (NYSE: UMC; TAIEX: 2303), (UMC) today reported unaudited net sales for the month of November 2004.

Revenues for November 2004

     Period            2004       2003    Y/Y Change  Y/Y (%)  M/M (%)
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    November        9,280,783  7,701,531   1,579,252  +20.51%   -7.78%
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   Jan.-Nov.      108,428,066 76,509,754  31,918,312  +41.72%     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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