A flat close that wasn’t quiet
Taiwan’s stock market returned from the October 9–11 National Day holiday on Monday and produced one of those sessions where the headline number hides the work being done underneath. The TAIEX closed at 49,301.96, down 11.48 points, or 0.02%, after opening 41.36 points lower, on turnover of NT$843.93 billion (roughly US$26.40 billion). A near-unchanged close would normally suggest a dull day. It wasn’t: foreign investors sold NT$52.20 billion of shares net — and the index absorbed it almost without flinching.
The absorption came from rotation rather than the heavyweights. The TWSE Shipping sub-index jumped 5.12% and Financials & Insurance gained 2.87%, while breadth was comfortably positive: 556 advancers against 465 decliners, with 101 unchanged. The exchange publishes foreign flow only in aggregate, not by stock or sector, but the price action tells a consistent story: the index heavyweights where foreign ownership is concentrated all closed lower, while local money went looking elsewhere.
Institutional flows: the signature numbers
| Investor group | Net trading value (Oct 12) | Direction |
|---|---|---|
| Foreign investors | NT$-52.20B | Net sell |
| Investment trusts | NT$+7.12B | Net buy |
| Dealers (prop + hedge) | NT$-14.29B | Net sell |
| Three institutions combined | NT$-59.37B | Net sell |
Monday’s outflow extends a trend: foreign investors had already net sold NT$23.66 billion over the shortened October 5–8 pre-holiday stretch. Investment trusts were the only institutional buyers on the day, a familiar pattern when domestic funds lean into financials and old-economy names while foreign desks lighten tech exposure.
Semiconductors: heavyweights down, sector up
The index’s biggest names all closed lower. TSMC (2330) slipped 0.39% to NT$2,540.00, Hon Hai (2317) fell 1.81% to NT$244.50, MediaTek (2454) lost 1.39% to NT$4,625.00, and UMC (2303) gave up 1.36% to NT$145.50. Yet the TWSE Semiconductor sub-index still rose 0.35% — the lifting was done by smaller chip names. With flow data available only in aggregate, that divergence is the strongest evidence — circumstantial, but consistent — that Monday’s pressure was a large-cap story rather than a sector-wide one.
TSMC remains in its pre-earnings quiet period (October 5–14) ahead of Thursday’s Q3 2026 earnings conference on October 15. The setup into that call is strong on the top line: September consolidated revenue came in at NT$511.86 billion, up 54.6% year over year, with AI hardware demand and advanced CoWoS packaging still anchoring the ecosystem. The cautious tone on Monday looked like position-trimming ahead of the event rather than a change of view.
The overseas tape offered little direction. The Philadelphia Semiconductor Index fell 0.41% at Friday’s US close, even as the S&P 500 rose 0.59% to 7,811.54; S&P futures traded 0.24% higher during Taipei hours on Monday. TSMC’s ADR closed at $453.31 on Friday in New York, about 14.0% above Monday’s Taipei close on a per-share basis. A reminder on reading that number: the ADR premium is structural — it has run roughly 15–25% in recent years given limited fungibility — and the two closes come from different sessions spanning Taiwan’s holiday. The level is not a mispricing signal; what’s worth noting is only that the gap currently sits toward the lower end of its habitual range, and day-to-day changes from here are the thing to track.
Derivatives positioning: pre-holiday snapshot only
Monday’s TAIFEX data had not yet been published as of writing, so the latest positioning picture dates to October 8, the last pre-holiday session. As of that session, foreign investors held a net open interest of -83,194 contracts in TAIEX futures (with a day’s net volume of -4,048), and the volume-based options put/call ratio stood at 87.14%. These figures describe the book going into the holiday — they are not Monday’s positioning and did not cause Monday’s move. The combination of a sizable pre-existing foreign net short in futures and Monday’s heavy cash-market selling is the context worth carrying into this week’s releases.
Currency and valuations
USD/TWD was little changed, trading around NT$31.92 on Monday, leaving the currency as a non-factor in the day’s flows.
Valuation marks as of the October 8 TWSE close, for reference into earnings week:
| Company | PER | PBR | Dividend yield |
|---|---|---|---|
| TSMC (2330) | 29.56 | 10.28 | 0.86% |
| MediaTek (2454) | 77.46 | 17.65 | 1.14% |
| UMC (2303) | 22.18 | 4.17 | 1.77% |
| Hon Hai (2317) | 16.41 | 1.83 | 2.88% |
| Delta Electronics | 62.54 | 17.38 | 0.59% |
Foreign investors hold 69.14% of TSMC’s shares outstanding — a structural fact that makes the heavyweights the natural place to feel a NT$52 billion foreign selling day, and Monday’s price action in the large caps fits that reading, even though the published flow data is aggregate only. It also explains why Monday’s rotation into shipping and financials was enough to keep the TAIEX flat anyway.
What to watch
- TSMC Q3 earnings, Thursday October 15. The quiet period ends October 14; the question is whether 54.6% year-over-year September revenue growth carries through to margin and capex guidance.
- Monday’s TAIFEX positioning data, once published. Whether foreign investors added to or trimmed the -83,194-contract net short futures book alongside their NT$52.20 billion cash selling will say a lot about whether this is hedged event-risk reduction or a directional call.
- Persistence of foreign cash outflows. NT$75 billion-plus of net selling across the past five trading sessions combined; a second heavy day, or a reversal after TSMC reports, sets the tone for the rest of October.
Disclaimer: This is an information and analysis publication, not investment advice. See our Methodology for data sources, standards, and our corrections policy.