On October 15, a US inflation shock, worries over an artificial-intelligence bubble and foreign selling combined to drive South Korea's KOSPI down more than 7%, to around the 5,500 level. Sell-side sidecars were followed by circuit breakers in both the KOSPI and KOSDAQ.
The Kyunghyang Shinmun issued a flash report on the 15th titled ‘Domestic stocks tumble more than 7%’, while financial outlets such as Financial News, Newspim and Businesskorea dubbed the day ‘Black Thursday’. Taken together, the reports say the KOSPI closed down 7.57%, retreating to roughly the 5,500 range, about a six-month low.
광고 문의 · 300×250During the session, sell-side sidecars were triggered first on both the KOSPI and KOSDAQ, and as losses deepened, both markets hit circuit breakers (temporary trading halts). Newspim reported that the index briefly fell more than 8% intraday, and the KOSDAQ also closed down more than 7%. Media Watch tallied that the index has shed about 21% over the past seven sessions.
What triggered the selling
Outlets such as Electronic Times and Digital Daily named a US price-data shock as the immediate trigger. Inflation running hotter than expected shook hopes for US rate cuts, they said, prompting selling across risk assets. Interpretations of the exact figures and the Federal Reserve's next steps differ by outlet, so this article does not assert them.
Analyses from Korea Duty-Free News and Topstar News added that ‘AI bubble’ concerns overlapped. Because semiconductor and AI-related stocks drove this year's KOSPI rally, they argued, valuation worries surfaced all at once. The reports identified a panic dump by foreign investors as a key factor widening the losses.
The blow was heaviest in large chip stocks. Seoul Economic Daily and others reported that Samsung Electronics fell to the 210,000-won range and SK hynix to the 1.26-million-won range, ‘back to April levels’. Given how heavily the KOSPI is weighted toward the two, their declines translated directly into the index's collapse.
Safety valves and the authorities
Sidecars and circuit breakers pause trading during sharp swings to give investors time to breathe. That both were triggered in both markets on the same day is unusual, and market participants appear to see the day as panic selling rather than an ordinary correction. However, we could not confirm any specific additional measures by the government or financial regulators in the reports reviewed.
Retail anxiety is also high. The Korea Economic Daily relayed investors saying they dread opening their brokerage accounts. Forced liquidation of margin positions is often cited as amplifying losses in volatile periods, but how large it was this time could not be confirmed.
The keys for the next session are whether foreign selling eases and whether US markets and the won stabilize. Experts are split between a possible short-term rebound and caution over further declines, so early trading on the 16th is likely to set the direction for the days ahead.
A third view: how the Chinese-speaking world and Asia see it
From a Chinese-speaking perspective, the rout does not look like a purely Korean problem. A structure in which a few chip heavyweights sway the whole market resembles Taiwan's, and it exposes a wider fragility in Asian markets leaning on the same AI-chip expectations. However, the specific moves in Taiwan, Hong Kong and mainland markets that day had not been confirmed at the time of writing.
There is also a counter-view. Some analysts call it an inevitable correction after this year's surge and stress that corporate earnings have not been damaged; the more cautious warn that if the US rate path and the AI investment cycle wobble together, Asian exporters across the board would be hit. Sino Bridge Times will follow up as more facts are confirmed.
