UMC greenlights extra $3.2B for AI buildout as shares slide 9%

UMC's board signed off on an extra capital expenditure budget of approximately $3.2 billion on October 28, 2026, earmarked for faster buildouts at its Singapore and Tainan, Taiwan sites. That cash does not replace anything: the chipmaker kept its existing $2 billion cash-based CAPEX outlook for 2026 intact, so the new figure sits alongside it rather than swapping it out.

The spending points at specialized technologies feeding AI infrastructure — advanced packaging, silicon photonics, silicon capacitors and lithium niobate modulators. Silicon photonics shifts data between chips using light instead of electrical signals, while lithium niobate modulators encode data onto those light signals, a key piece of faster optical links. Nobody sees the payoff soon: UMC expects initial production ramps in late 2028 and full capacity by 2030.

The announcement rode along with third-quarter 2026 earnings that gave management some cover. UMC posted record wafer shipments for the quarter, revenue of NT$74.24 billion — up 25.6% year-over-year and 8% from the previous quarter — and an operating margin of 25.1%. Capacity utilization hit 92%, and the 22nm process accounted for 18.3% of total wafer sales.

Management paired the outlay with forward numbers of its own: roughly 10% year-over-year growth in blended average selling price in 2027, and AI-related revenue topping 25% of total revenue by 2029. Blended ASP reflects the average price UMC pulls in per wafer across its product mix.

Shares still fell about 9% on October 29, the day after the approval, with margin pressure driving the selloff. New fabs and equipment get depreciated over time, and that cost lands on the income statement while operating expenses climb during the buildout — before any of the new capacity produces revenue. For shareholders, the costs arrive well before the late-2028 to 2030 payoff window.