Business & Markets
South Korea’s KOSPI drops 5.46% as chip rout revives AI trade concerns
Reports of faster progress by China’s CXMT and broader doubts about AI investment returns were cited as pressures on chip shares. The session shows how concentrated the Korean benchmark is in technology; it does not prove AI demand or chip earnings have turned down.
Executive summary
- A sharp reversal from the intraday low: The Korea Composite Stock Price Index closed Tuesday at 6,035.35, down 348.89 points or 5.46%, according to Yonhap, citing Korea Exchange data. It had fallen below 6,000 during the session and was down more than 7% at its low, AP and Reuters reported. The close recovered part of the intraday loss.[1][2][3]
- Chipmakers drove the decline: Samsung Electronics fell 7.39% and SK Hynix fell 10.09% by the close, Yonhap reported. The sell-off followed reports of technology advances by Chinese memory maker CXMT and investor concerns about competition and the returns on AI-related spending. Those explanations reflect market reporting and commentary; they do not establish that either Korean company has lost a technological lead or that AI demand has weakened.[1][2][3]
- Trading was briefly curbed: The Korea Exchange activated a sell-side sidecar in the morning amid the sharp decline, pausing program trading for five minutes, Yonhap reported. KRX guidance says the KOSPI sidecar trigger is a 5% or greater move in KOSPI 200 futures sustained for one minute; the exchange suspends ask quotations for program trading when prices fall. It is not a market-wide halt or evidence that trading was suspended for the day.[4][5]
South Korea’s KOSPI finished Tuesday at 6,035.35, down 5.46% from its previous close, according to Yonhap citing the Korea Exchange. The benchmark had dropped below 6,000 intraday and was down more than 7% at its low, AP and Reuters reported, before recovering part of the loss. It was the fifth consecutive session lower, according to Yonhap.[1][2][3]
The two biggest semiconductor names were among the steepest decliners. Samsung Electronics ended down 7.39% and SK Hynix fell 10.09%, Yonhap reported. Foreign investors were net sellers of 4.51 trillion won in KOSPI shares, while domestic institutions and individuals were net buyers, the agency said. The index’s heavy exposure to semiconductor leaders amplified the effect of the sector’s move; the daily price action alone does not show a lasting change in earnings or demand.[1][2]
Reports about progress at Chinese memory-chip maker ChangXin Memory Technologies (CXMT) added to concern that competition could intensify for established suppliers, AP and Reuters reported. Reuters also described broader investor questions about how quickly the large build-out of AI infrastructure will generate returns, while Yonhap cited an analyst who pointed to concerns about OpenAI revenue and the completion of Korean chipmakers’ share buybacks. These are reported market explanations and investor concerns, not confirmation that CXMT has overtaken Samsung or SK Hynix or that AI demand has peaked.[2][3][1]
Inflation and energy risks were another part of the backdrop as conflict in the Middle East continued to weigh on markets, AP and Reuters reported. The day’s trading does not isolate one cause: Korean shares had already been falling, U.S. technology stocks also declined, and investors were watching inflation data and company earnings. A volatile session can change expectations quickly, but it is not on its own evidence of a sustained turn in the AI investment cycle.[2][3][1]
The Korea Exchange activated a sell-side sidecar at 9:48 a.m. local time amid the sharp decline, Yonhap reported. KRX’s trading guide says the KOSPI trigger is a 5% or greater move in KOSPI 200 futures sustained for one minute; on a fall, the exchange suspends ask quotations for program trading for five minutes. A sidecar is distinct from a circuit breaker that halts the broader market. The sidecar ended after its limited window and did not stop regular trading for the session.[4][5]
The session underscores the market’s sensitivity to the semiconductor and AI investment outlook, but the implications remain uncertain. The fall below 6,000 was followed by a partial recovery before the close; upcoming earnings and inflation data may offer more evidence about demand, margins and investor positioning than one day’s index move can provide.[2][3][1]