KOSPI trips a circuit breaker as the AI chip sell-off deepens
Asian chip stocks led a broad slide after Wall Street fell on inflation and AI spending worries.
What happened
Sharp falls triggered a trading halt on South Korea's Kospi, and Japan's Nikkei 225 sank 5%. Taiwan Weighted closed down 3.41%. The slide followed Wall Street lower. Two days earlier, the Broadcom boss had warned of a casino mentality in AI investing, and declines for Samsung and SK Hynix had already dragged the Kospi sharply lower.
Sources: Financial Times, Investing.com. Details
Why it matters
Korean and Taiwanese markets lean heavily on chipmakers, so doubts about the scale of AI spending hit them first. Our data show the KOSPI at 6,008.81 as of October 14, 2026, which is -34.07% from its 52-week high. It was down -11.69% over the week even before today's halt, and -12.13% for October so far.
What history shows
The KOSPI has averaged -0.43% in October since 1997, and finished the month higher in 45% of 29 years.
After tariff escalation headlines, the KOSPI averaged -3.22% over the next five trading days, across 8 cases. That is a different trigger, but it shows how Korean stocks have behaved after sharp shocks.
Seasonal backdrop
November is one of the stronger months for the KOSPI, with an average of +2.91% since 1997. Seasonal tendencies are weak guides when a sell-off is already under way.
Scenarios
Possible paths and the signs that would point to each. No probabilities. Testable ones are graded on the scorecard.
Chip doubts fade
Sellers tire once AI spending news stabilises, and Korean chipmakers recover part of the drop.
- No further circuit breaker trips in the KOSPI
- Samsung and SK Hynix stop making new lows
Sell-off feeds on itself
Higher bond yields and AI debt worries keep pressure on chip valuations across Asia.
- Another trading halt in Seoul or a further sharp fall in Tokyo
- US chip stocks keep sliding
What to watch
- Whether the KOSPI halts again
- How Wall Street chip stocks open
- Any new comment on AI spending from large chip firms
Sources and method (4)
- Sharp falls triggered a trading halt on South Korea's Kospi, and Japan's Nikkei 225 sank 5%, following Wall Street lower. Financial Times, Oct 15
- South Korea's KOSPI triggered a circuit breaker in a tech rout that sent Asia stocks tumbling. Investing.com, Oct 15
- Taiwan Weighted closed down 3.41%. Investing.com, Oct 15
- Chip stocks slid after the Broadcom boss warned of a casino mentality in AI investing, and declines for Samsung and SK Hynix dragged Korea's Kospi sharply lower. Financial Times, Oct 13