Taiwan’s benchmark jumped 1,250.94 points on Wednesday as a record-setting Wall Street session and a 6.5% surge in the Philadelphia Semiconductor Index lit up the AI hardware complex. Foreign investors bought NT$90.31 billion of cash equities — the day’s defining number.
Taipei, Aug 4: closing prints conflict — our quote feed shows the TAIEX at 43,360.66 (+0.56%) while media reports put the close at 43,289 (-0.22%) — but the rotation was unambiguous. TSMC fell 2.11% as the semiconductor sub-index rose 1.37%, investment trusts bought NT$25.27B against NT$5.73B of foreign selling, and the TWD softened to 32.41.
Taiwan’s TAIEX closed up 0.62% at 43,386.41 on Monday despite a 2.27% drop in TSMC, as MediaTek’s near-limit-up surge and rotation into memory and passive components carried the tape. Foreign investors sold NT$19.19B; investment trusts bought NT$21.07B.
The TAIEX surged 7.98% to 43,119.75 on Friday, recovering a large slice of a five-session, near-11% plunge. Foreign investors net bought NT$67.55 billion as TSMC, MediaTek and UMC closed at or near their 10% daily limits.
After a two-day, 3,595-point rout, the TAIEX fell to 39,404 and then rallied more than 1,000 points intraday, closing at 39,933.30 (-0.26%) as UMC’s earnings-driven surge offset another NT$48.3B of foreign selling.
TSMC carries roughly 35% or more of the TAIEX’s capitalization weight, so a 1% move in the stock mechanically shifts Taiwan’s benchmark by about 0.35 percentage points before any other share trades. Here is how to decompose any TAIEX session into its TSMC and non-TSMC components — with worked examples from real July 2026 data.
Taiwan’s benchmark fell 4.65% to 41,603 on Tuesday as foreign investors dumped a net NT$87.56 billion. MediaTek and UMC fell close to 10%, TSMC lost 2.98%, and the sell-off tracked a region-wide unwind of AI infrastructure trades.
Taipei absorbed a -4.25% overnight drop in the Philadelphia Semiconductor Index with barely a scratch: the TAIEX closed at 43,634.19, down just 0.05%, as foreign investors net bought NT$8.04B and financials rallied 1.45%. MediaTek and UMC bore the brunt while TSMC ended unchanged.
The TAIEX fell 1,195.97 points to 43,654.84 on Friday as a Wall Street rout over AI spending and $100 oil hit Taipei. Foreign investors sold a net NT$60.95 billion in cash equities, with UMC down 7.6% and MediaTek off 3.2%.
Taiwan’s benchmark closed barely changed Thursday after a whippy session that briefly reclaimed 45,000. All three institutional groups bought — foreign investors for a second day — even as the previous session’s futures book showed foreigners still heavily net short.