Korea’s KOSPI closed at 6,598.26, up 3.76%, after AI semiconductor euphoria from Wall Street triggered a buy-side sidecar and produced 12 limit-up stocks — the most in a day since tracking began in June 2022. Foreigners bought over 1.4 trillion won intraday while retail investors sold.
A day after a 5.12% plunge, the KOSPI swung from +1.8% to -2.7% intraday before stabilizing near 6,228 by late morning, as Samsung Electronics and SK Hynix steadied. The KOSDAQ was up nearly 5% by late morning, triggering its third consecutive buy-side sidecar as money rotated into biotech, robotics and batteries. Figures for August 4 are an intraday snapshot, not final closes.
The KOSPI fell 5.12% to 6,257.45 as traders booked profits from Friday’s record 17.91% surge, with Samsung Electronics and SK hynix both down almost 9%. The KOSDAQ climbed 2.44% and triggered a buy sidecar as money rotated into bio and robotics names.
The KOSPI surged 17.91% to 6,595.45 — its biggest one-day gain on record — as strong US tech earnings eased AI profitability fears and foreign investors piled back in after a brutal two-week selloff capped by back-to-back circuit breakers.
Seoul stocks rebounded Monday: KOSPI +0.97% to 6,755, KOSDAQ +2.22%. Falling oil and AI-summit optimism lifted sentiment, with NAVER up 8.4% on an Nvidia investment, even as foreign investors dumped roughly $2.0B of KOSPI shares.
The KOSPI fell 5.72% and the KOSDAQ 5.32% as new US tariffs, oil above $100 and an overnight Wall Street slide hit at once, triggering sell sidecars. Foreigners dumped roughly $2.2B of KOSPI shares while Samsung Biologics jumped 10% on record earnings.
The KOSPI opened up 4.51% on a US chip rally, triggered the year’s 20th buy-side sidecar, then gave back most of the gain to close at 6,797.70 (+0.74%) as oil and earnings caution weighed. Foreigners bought a net KRW 2.63T.
Korea’s KOSPI jumped 3.56% to 6,747.95 as Samsung Electronics surged 6.15% and chip stocks led a rebound, tripping the year’s 19th buy-side sidecar. Foreign and institutional buying drove the bounce after a brutal three-week slide.
Korea’s KOSPI jumped 7.01% to 7,284.41 after a softer US CPI print eased Fed tightening fears, tripping buy sidecars on both exchanges. Foreign investors bought roughly $1.6 billion of KOSPI shares, but the index remains about 14% below its June 30 level.
Korea slows a crashing market in three layers: sidecars pause program trading at a 5% futures move, circuit breakers halt everything at index drops of 8%, 15%, and 20%, and volatility interruptions cool single stocks. Here is how each trigger works, in what order they fire, and how to read the flow data around a halt.