The TAIEX gave back an early bounce to close down 0.52% at 42,449.70 in the first session after Friday’s record plunge. TSMC rose on a $100B Arizona expansion, but UMC cratered 9.7%, foreigners kept selling, and investment trusts did the buying.
Taiwan’s benchmark fell 6.47% to 42,671 on Friday as an overnight 4.29% rout in the Philadelphia Semiconductor Index swept through Taipei. TSMC dropped 7.29% despite a record Q2, UMC closed limit-down, and foreign investors had already sold NT$48.3 billion of cash equities heading into the session.
The TAIEX closed at 44,737.95 on Tuesday, down 1.42%, as renewed U.S.-Iran tensions and Monday’s 4.78% drop in the Philadelphia Semiconductor Index hit Taipei. Foreign investors sold a net NT$51.89 billion, with TAIFEX settlement Wednesday and TSMC earnings Thursday.
Taiwan’s five largest tech exporters must disclose revenue every month — a disclosure rule almost no other major market imposes. Here’s how to read those filings, with TSMC, Hon Hai, Delta Electronics, MediaTek, and UMC’s June 2026 numbers as a worked example of what accelerating AI demand looks like in the data.