TAIPEI, Taiwan--(BUSINESS WIRE)--United Microelectronics Corporation (NYSE: UMC; TWSE: 2303) (“UMC”), today reported unaudited net sales for the month of May 2025. Revenues for May 2025 Period 2025 2024 Y/Y Change Y/Y (%) May 19,480,057 19,509,486 -29,429 -0.15% Jan.-May 97,793,544 93,882,976 3,910,568 4.17%

All figures in thousands of New Taiwan Dollars (NT$), except for percentages (**) All figures are consolidated Additional information about UMC is available on the web at https://www.um.