United Microelectronics Corporation (UMC) experienced a 24-hour plunge of 5.05%, as the stock faced significant selling pressure during the trading session.

The decline came amid broad weakness in the semiconductor sector, with key industry peers also trading lower, which contributed to negative market sentiment and dragged down the stock.

Furthermore, UMC saw concentrated profit-taking from investors following a recent rally, driven by uncertainty over speculative reports regarding a potential partnership with Intel. The company has issued a statement discouraging reliance on market rumors and urging attention to official disclosures, which heightened caution and triggered the sell-off.