TPEx and TWSE July 21 Margin-Trading Adjustments: Walsin Technology, Ten Ren, and Four Other Stocks Face Restrictions

What margin-trading and short-margin adjustments apply to Walsin Technology (2492, 華新科)?

According to a MoneyDJ report on TPEx notices, Walsin Technology (2492) was placed under monitored disposition for the second time (or more) within the most recent 30 trading days, with the disposition period running from July 21, 2026 to August 3, 2026. Under this designation, the exchange announcement states the margin ratio is reduced to zero and the short-margin requirement is raised by 10 percentage points ¹.

The same report notes a separate, cumulative adjustment tied to excessive price volatility: because Walsin Technology is "currently undergoing margin/short-margin ratio adjustment" for volatility, its margin ratio remains at zero while its short-margin requirement is cumulatively raised by 20 percentage points ². The two measures — the monitored-disposition rule and the volatility-driven adjustment — are reported as running concurrently for the same ticker.

Which stocks had margin ratios adjusted starting July 21 due to abnormal trading volume?

According to the same MoneyDJ report, Ten Ren (1233) showed excessive trading volume from July 14 to July 20, 2026, triggering a rule-based reduction of its margin ratio by 10 percentage points and an increase in its short-margin requirement by 10 percentage points, effective July 21, 2026 ³.

Ticker 3236 (千如) and Ticker 3441 (聯一光) are reported to have shown "consecutive five trading days" of excessive volume over the same July 14–20 window, resulting in the identical adjustment — margin ratio down 10 points, short-margin up 10 points — from July 21, 2026. The notice adds that restrictions will lift the business day after six consecutive trading days without the triggering condition ⁴.

What changed in Ticker 8043 (蜜望實)'s monitoring status?

According to the MoneyDJ report, Ticker 8043 (蜜望實) had gone six consecutive trading days through July 20, 2026 without excessive price volatility. However, the notice states the stock still shows excessive trading volume, so its margin ratio remains reduced by 10 percentage points and its short-margin requirement remains raised by 10 percentage points, pending resolution of the volume condition ⁵.

Which block trades were matched on TPEx's July 21 large-lot trading day?

According to a separate MoneyDJ report on TPEx large-lot (鉅額) trading, three single-type paired block trades were recorded on July 21, 2026:

• Ticker 8358 (金居) traded 714,000 shares at NT$380, for a transaction value of NT$271,320,000 ⁶.
• Ticker 4105 (東洋) traded 2,508,000 shares at NT$79.5, for a transaction value of NT$199,386,000 ⁷.
• Ticker 5274 (信驊) traded 2,000 shares at NT$13,010, for a transaction value of NT$26,020,000 ⁸.

What are the rules and investor eligibility for cash day-trading?

According to TPEx's day-trading rules page, cash (現股) day-trading was phased in over 2014: investors were permitted to buy-then-sell same-day starting January 6, 2014, and sell-then-buy same-day trading was opened starting June 30, 2014 ⁹.

Eligibility requires investors to have held a brokerage trading account for at least three months and to have executed at least 10 trades in the past year — a condition waived for investors who already hold a margin-trading account or who qualify as professional institutional investors ¹⁰.

On securities-lending fees tied to day-trading, the rules cap the applicable borrowing-fee rate for day-trade share-difference settlement at no more than 7% of the security's closing price on the day of sale ¹¹.

What this means

The July 21 notices show six different tickers — 2492, 1233, 3236, 3441, 8043, and by extension any repeat offenders — placed under margin or short-margin restrictions on the same effective date, but for two distinct regulatory triggers reported in the source: monitored disposition for repeated volatility flags (2492, per E1–E2) versus a volume-based rule applied uniformly to 1233, 3236, 3441, and 8043 (E3–E5). Notably, 2492's combined restriction (zero margin ratio, 20-point cumulative short-margin increase) is more severe than the flat 10-point adjustments applied to the volume-triggered group, reflecting its status as a repeat monitored-disposition case rather than a first-time volume flag. Separately, the day-trading eligibility rules (E9–E11) and the large-lot block trades (E6–E8) reported for the same date describe distinct market mechanisms — investor qualification standards and negotiated large-block settlement — that the source material does not link causally to the margin-adjustment list.