A record month ends with a fade, not a failure
The TAIEX closed the last session of September up 308.17 points, or 0.65%, at 47,940.13 — trimming a morning surge of more than 700 points that had carried the index to a session high of 48,380 before afternoon profit-taking set in. Turnover was heavy at NT$875.67 billion. The pullback off the highs did nothing to spoil the bigger picture: the index added 1,811.66 points in September, a 3.93% monthly gain, and finished the quarter at an all-time high.
The setup was familiar. The Philadelphia Semiconductor Index rose 1.32% to 12,629.16 in Tuesday’s US session even as the broader tape sagged — the S&P 500 slipped 0.17% and the Nasdaq eased under pressure from rising Treasury yields ahead of PCE inflation and labor data. Taipei took its cue from the chip index, as it usually does, and overnight S&P 500 futures ticking up 0.20% kept the afternoon fade orderly.
Institutional flows: all three legs buying
The day’s defining number was the foreign bid. All three institutional categories were net buyers, combining for NT$38.66 billion:
| Investor group | Net trading value (Sep 30) |
|---|---|
| Foreign investors | NT$+29.64B (net buy) |
| Investment trusts | NT$+7.78B (net buy) |
| Dealers (prop + hedge) | NT$+1.24B (net buy) |
| Combined | NT$+38.66B |
That cash-market buying sits against a still-cautious derivatives book: as of Tuesday’s session — Wednesday’s TAIFEX data is not yet published — foreign investors held a net short position of 79,029 contracts in TAIEX futures, and the volume-based put/call ratio stood at 90.39%. The gap between fresh cash inflows and a large standing futures short is worth watching; it is the change in that futures position over the coming sessions, not the level alone, that will tell us whether Wednesday’s buying was allocation or hedged flow.
Heavyweights quiet, second-liners loud
The big caps did the steering without the fireworks. TSMC gained NT$5.00 (+0.20%) to NT$2,480 after touching NT$2,510 intraday, supported by expectations for advanced-process order visibility stretching toward 2030 ahead of its investor conference in two weeks. MediaTek added NT$10.00 to NT$4,920 (+0.20%), Hon Hai rose NT$1.00 to NT$251.50 (+0.40%), and UMC matched the index at +0.65% to NT$154.50. Quanta was a notable laggard, off NT$3.00 to NT$333.50.
The real action was downstream of Nvidia headlines. Reports that the company may adopt glass substrates in next-generation AI packaging sent AUO, Innolux, HannStar Board, G-Tech Optoelectronics and TPK-KY to their daily limit-up. Silicon wafer suppliers followed the same script, with GlobalWafers, Sino-American Silicon and Wafer Works all locked at the limit. By sector, Shipping led at +1.52%, Semiconductors rose 0.45%, and Financials were flat at +0.01% — a tape driven by AI hardware themes rather than broad rotation.
Leverage and the short book
Keeping Taiwan’s three channels separate, as always: on the retail leveraged-long side, the market-wide margin loan balance (through Tuesday, the latest published) stood at NT$618.7 billion, up NT$3.55 billion — retail adding modestly into strength, with UMC the standout at +9,448 lots of new margin longs. On the institutional short channel, SBL balances rose in 396 shortable issues and fell in 522, a mild net-covering skew. Within the big caps the covering was consistent: TSMC’s SBL balance fell 130,000 shares, MediaTek’s fell 317,472, and UMC’s dropped 5.6 million shares — notable given the simultaneous retail margin build there. Delta Electronics was the exception, with SBL borrow up 223,000 shares against its rich multiple (58.4x trailing earnings at Tuesday’s close).
One housekeeping note on TSMC’s ADRs: TSM closed at $456.94 in Tuesday’s US session, roughly 17% above the Taipei close on an adjusted basis. That premium is structural — it has run in the mid-teens to mid-twenties for years owing to limited fungibility — and the two closes come from different sessions. The level is not a mispricing signal; only meaningful day-to-day shifts in the gap carry information, and Wednesday’s reading sits comfortably inside the recent range.
Currency: quarter-end tug of war
The New Taiwan dollar came under pressure intraday, trading through 31.9 per US dollar before quarter-end exporter conversions and central bank smoothing anchored the rate around 31.876–31.90; the session mark was 31.85, off 0.21%. A softer TWD alongside NT$29.6 billion of foreign net buying suggests the equity inflow was more than offset by other outflows or hedging demand on the day — a combination that bears monitoring into the new quarter.
What to watch
- Foreign futures positioning: whether Wednesday’s NT$29.64B cash buying is confirmed by a reduction in the 79,029-contract net short in TAIEX futures when Wednesday’s TAIFEX data publishes.
- US inflation and labor prints: rising Treasury yields pressured stocks overnight ahead of the PCE and jobs releases, and those data remain the near-term macro swing factor for the SOX–TAIEX transmission.
- TSMC’s investor conference in two weeks: the 2030 advanced-process visibility narrative is now embedded near record levels at NT$2,480; guidance will test it.
Disclaimer: This is an information and analysis publication, not investment advice. See our Methodology for data sources, standards, and our corrections policy.