The TAIEX rose 1.11% to 46,021.48 on Thursday, a fourth straight gain, as a cool US CPI print and a 2.49% SOX rally powered semiconductors. Foreign investors net bought NT$75.69 billion in the cash market, MediaTek jumped 5.23%, and Hon Hai bucked the tape.
TAIFEX publishes foreign investors’ net open interest in TAIEX futures and the options put/call OI ratio every trading day — but a large negative net OI is usually a hedge, not a bearish bet. Here is how to read both gauges, with a worked example from real August 2026 data, the practitioner heuristics and their limits, and the divergences that matter.
The TAIEX closed at 45,518.07 on Wednesday, up 0.88%, as TSMC’s record NT$467.58 billion July revenue and a fresh capex approval lifted the tech complex. All three institutional groups were net buyers, led by NT$11.02 billion of foreign inflows, with the US CPI print looming overnight.
Taipei reversed an early 276-point drop to close up 0.43% at 45,120.72 on Tuesday, defying a 2.94% overnight slide in the Philadelphia Semiconductor Index. Foreign investors net bought NT$22.33 billion, MediaTek and TSMC led the recovery, and passive-component names went limit-up on AI server demand.
Taiwan stocks jumped 702.85 points Monday as foreign investors swung back to a NT$51.71B net buy, UMC surged 6%, and TSMC filed a record NT$467.58B July revenue on filing-deadline day.
Taiwan’s benchmark faded from an early push past 44,800 to close at 44,225.91 on Friday, down 0.38%, as foreign investors sold a net NT$40.72 billion in the cash market. TSMC edged higher against the tide; UMC fell 4.5%. Monthly revenue filings land Monday.
Taiwan’s TAIEX fell 0.48% to 44,396.70 on Thursday as TSMC and MediaTek gave back part of Wednesday’s 1,250-point surge. Investment trusts bought NT$8.86B while foreigners were marginal net buyers in the cash market; rotation lifted memory and cooling names even as the heavyweights sagged.
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.