Tuesday in Taipei was two sessions in one. The TAIEX opened into the teeth of an overnight US semiconductor selloff, fell more than 552 points to an intraday low of 44,210.31, and then spent the afternoon clawing it all back — closing at the day’s high of 45,169.46, up 407.14 points (+0.91%) and back above the 45,000 line. Total turnover was NT$696.05 billion, a consolidation on reduced volume relative to recent peak sessions. The defining feature was rotation: financials, not chips, carried the tape home.
How the reversal happened
The early damage was imported. In Monday’s US session the Philadelphia Semiconductor Index dropped 2.70% and the S&P 500 slipped 0.28% as investors trimmed AI-related exposure ahead of Nvidia’s earnings report. Taipei’s chip complex opened accordingly weak — TSMC (2330) traded as low as NT$2,350 — before afternoon bargain-hunting took over. Late-session buying, including 2,997 lots on the closing tick, lifted TSMC to NT$2,400, up NT$25 (+1.05%) on the day. Overnight S&P 500 futures ticking up 0.24% gave the afternoon bid some cover.
The real leadership sat elsewhere. The Financials & Insurance sub-index jumped 2.31%, with Fubon Financial surging over 7% to a record high and solid gains across Cathay, KGI and CTBC Financial. The Semiconductor sub-index finished up a more modest 0.89% and Shipping added 0.51%. Beneath the surface, memory names erased early losses, PCB upstream material suppliers ITEQ and Taiflex hit limit-up, and optical communication names such as Tyntek and AmTRAN also locked in limit-up gains. Among the other large caps, Hon Hai (2317) eased 0.21% to NT$243, MediaTek (2454) fell 0.80% to NT$3,735, and UMC (2303) rose 1.21% to NT$125.
Institutional flows: a shallow combined sell
Official TWSE data show the three major institutional categories combined for a net sale of NT$5.34 billion on Tuesday — a light print against a NT$696 billion tape.
| Investor category | Net trading value (Aug 25) | Direction |
|---|---|---|
| Foreign investors | NT$-0.79B | Net sell |
| Investment trusts | NT$-4.61B | Net sell |
| Dealers (prop + hedge) | NT$+0.06B | Marginal net buy |
| Combined | NT$-5.34B | Net sell |
The composition is worth a beat: domestic investment trusts, not foreigners, did most of the selling. Foreign net selling of under NT$1 billion on a day that opened down 552 points suggests offshore money was not chasing the morning weakness lower — consistent with a market that found its footing by the close.
Positioning and leverage: what the prior session showed
Derivatives and leverage data run a day behind, so treat the following as Monday’s positioning backdrop rather than an explanation of Tuesday’s move. As of the August 24 session, foreign investors’ TAIEX futures net open interest stood at -82,529 contracts (day’s net volume a negligible +108), a sizable net short book against a spot market that has just reclaimed 45,000. The options put/call ratio sat at 95.81% on open interest and 106.18% on volume — neither at an extreme.
On the leverage side, keeping Taiwan’s three channels separate: market-wide margin purchases (retail leveraged longs) stood at NT$545.3 billion as of Monday, down NT$1.68 billion — retail was trimming rather than adding into the pre-selloff tape. In the institutional short channel, SBL short balances rose in 550 shortable issues and fell in 292 on Monday. The single-name detail cuts both ways: SBL shorts were added in UMC (+1.23 million shares), Hon Hai (+898,000) and MediaTek (+291,000), but reduced in TSMC (-269,000 shares) and Delta Electronics (-99,000). Retail margin shorts in TSMC also fell 14 lots. Whoever is pressing shorts institutionally, they are doing it around the index heavyweight rather than in it.
Currency and the ADR gap
The New Taiwan dollar weakened, with USD/TWD closing at 31.86 (+0.13%) after trading around 31.889 at midday on half-day turnover of US$685 million — a mild headwind consistent with the small foreign cash outflow. TSMC’s ADR closed Monday’s US session at $410.12, roughly 8.9% above Tuesday’s Taipei close on a share-adjusted basis. That gap is structural — the ADR has habitually traded at a 15–25% premium in recent years given limited fungibility, and the two closes come from different sessions — so the notable point is that the premium currently sits below its recent range, not that any arbitrage exists. Day-to-day movement in that gap, especially around Nvidia’s report, is the thing to track.
What to watch
- Nvidia earnings and the SOX response. Tuesday’s reversal was built on afternoon bargain-hunting into a still-cautious global AI tape; the guidance will test whether the NT$2,350 dip in TSMC was the low that mattered.
- Today’s TAIFEX prints, when published. Whether foreign investors held or covered the -82,529-contract TX net short into the reversal will say more about conviction than Tuesday’s shallow NT$0.79 billion cash-market sale.
- Follow-through in financials. A 2.31% sector-index day with Fubon at a record high is rotation leadership; watch whether it persists once semiconductor volatility settles.
Disclaimer: This is an information and analysis publication, not investment advice. See our Methodology for data sources, standards, and our corrections policy.