South Korea’s Kospi and Kosdaq each fell more than 8% on Thursday, October 15, triggering back-to-back trading halts as a technology sell-off, hotter U.S. inflation and concerns over artificial-intelligence financing rattled investors.
The Kosdaq crossed the circuit-breaker threshold first, at about 12:23 p.m. Seoul time, and the Kospi followed roughly 15 minutes later. Under the exchange’s rules, a drop of at least 8% that lasts for one minute prompts a 20-minute suspension of trading. At the halts, the Kosdaq was down 8.01% at 757.88, while the Kospi had fallen 8.00% to 5,528.05, from the previous close of 6,008.81.
Heavy selling in semiconductor giants Samsung Electronics and SK Hynix added pressure to the indexes. Investors were also reacting to U.S. inflation data showing consumer prices rose 3.7% year over year in September, above forecasts, reviving worries about interest rates staying high. Concerns about the cost and returns of AI investment added to the strain on technology shares.
The paired halts were the first on both markets since July 29, highlighting how quickly global tech and rate concerns can shake South Korean stocks.