The KOSPI has stabilized sharply after South Korean financial authorities tightened rules on ultra-high-risk single-stock leverage products linked to Samsung Electronics and SK Hynix, but the calmer market has come with a steep decline in trading activity. Sidecar triggers fell to five through the 28th, from 15 last month and 25 across June and July, while circuit breakers were not activated this month after four activations last month. Volatility also moderated, with moves above 3% occurring on 42% of trading days this month versus 64% last month, and moves above 5% falling from 10 days to three. The VKOSPI (KOSPI 200 volatility index), a gauge of expected market turbulence, dropped more than 40% in 20 trading days to close at 50.08 on the 28th. The stabilization followed a rise in the minimum deposit for single-stock leverage products from 10 million won to 30 million won. Average daily KOSPI trading volume and value fell to yearly lows, while the turnover rate declined to 0.54%. Retail investors net-sold 1.77 trillion won of 16 Samsung Electronics- and SK Hynix-linked leverage and inverse products after the rules took effect, reversing 15.29 trillion won of net purchases beforehand. Their combined average daily trading value fell to 1.01 trillion won this month, one-nineteenth of the pre-regulation level. The index, which reached 9,385 intraday in June before falling to 5,262 late last month, has repeatedly failed to hold above 7,000. Analysts say a sustained breakout will be difficult without new liquidity, although reduced semiconductor concentration could allow a broader sectoral rally. Investment demand has shifted toward other leveraged products, including KODEX funds and QLD, while weaker expectations for corporate earnings growth next year could keep the KOSPI rangebound around 7,000 for an extended period.