Taiwan’s benchmark weighted index fell 492.93 points, or 0.99 percent, to close at 49,313.44 on Thursday as investors trimmed positions before the Double Ten holiday and U.S. Treasury yields climbed to multi-decade highs, pressuring large-cap chip and handset stocks.
Turnover reached NT$869.7 billion, shy of the NT$1 trillion sessions seen during the September rally. The index opened at 49,783.06, touched a session low of 49,189.77 and never recovered, with foreign and proprietary desks cited by brokers as net sellers into the close.
Cap-weighted drag
Taiwan Semiconductor Manufacturing Co. slid NT$35 to NT$2,550, a 1.35 percent drop that alone subtracted roughly 277 index points, brokers estimated. MediaTek fell NT$145 to NT$4,690, down 3 percent, while Hon Hai Precision Industry lost 1.19 percent to NT$249. Delta Electronics and Quanta Computer also retreated more than 1 percent as the Philadelphia semiconductor index logged its steepest slide in months overnight.
Analysts tied the weakness to rising 10- and 30-year U.S. yields, which make future earnings from growth stocks less attractive on a discounted basis. With cash markets closed Friday through Sunday for National Day, many funds chose to lock in gains after the index flirted with 50,000 earlier in the week.
Countertrends under the surface
Not every subgroup followed the retreat. Memory packaging names such as Nanya Technology and ASE Technology Holding contributed positive index points, reflecting continued AI server demand. Passive-component makers including Walsin Technology and Yageo saw selective buying after strong September revenue prints.
Defensive plays drew attention as influenza and COVID-19 cases climbed. Medtecs International Corp. and several biotech names hit daily limits, while mask and hygiene suppliers rallied for a second session. Formosa Plastics Group shares surged after executives struck an upbeat tone on 2027 petrochemical demand, lifting the plastics sub-index toward a four-day high.
Positioning into the holiday
Securities houses warned that thin liquidity during the long weekend could amplify moves when trading resumes Tuesday. TSMC’s September revenue, reported earlier in the week at NT$511.86 billion, remains a focus ahead of next week’s investor conference, where management may update capital spending and advanced-node mix.
Technical strategists said support now clusters near 49,000, with resistance still pegged at the psychological 50,000 level. Unless U.S. bond yields stabilize, they expect choppy range trading rather than a clean breakout—especially while investors wait for third-quarter earnings from Apple suppliers and AI server assemblers.