Taiwan's stock market jumped on strong Nvidia earnings, but chipmaker UMC fell sharply after announcing a big fundraising plan — bad news for its shareholders in the short run.

• UMC's board approved up to $1.8 billion in overseas convertible bonds, and the stock dropped 4% on heavy selling by both local funds and foreign investors.
• The worry is dilution: if those bonds turn into shares later, existing shareholders own a smaller slice.
• The money is not for paying off debt — it goes to new equipment, a Singapore expansion, and a new plant in southern Taiwan to meet AI and specialty chip demand.
• That heavy spending is itself a signal, since UMC has not been a company that throws money at expansion — management clearly expects years of strong demand.
• The wider market ran hot: passive components, PCB makers, and optical suppliers all surged as AI data centers drive demand for faster data links.

Outlook: UMC's stock may stay under pressure while the dilution worry lingers, even as the broader AI-driven rally in Taiwan continues.