Seoul Shares Plunge Over 7% Amid Chip Sector Rout and Inflation Concerns

On October 15, 2026, the South Korean stock market saw a dramatic decline, with the benchmark Korea Composite Stock Price Index (KOSPI) dropping by 7.57%, closing at 5,554.22 points. This marked the longest losing streak for the index since September 2024, as it fell for the seventh consecutive session.

The decline was primarily attributed to significant losses in major chipmakers, exacerbated by rising concerns over inflation and the sustainability of investments in artificial intelligence (AI). The KOSPI opened 5.59% lower and experienced a sharp sell-off, prompting the Korea Exchange to activate a circuit breaker to halt trading temporarily after the index dropped over 8%.

Major companies in the technology sector were heavily impacted, with Samsung Electronics plunging nearly 9.5% and SK Hynix falling over 11%. Analysts noted that the market's downturn reflects growing apprehension regarding the competitive landscape in memory chip production and increasing borrowing costs.

As the U.S. market closed lower the previous day due to similar concerns, investor sentiment in South Korea remained fragile. The Korean won also weakened against the U.S. dollar, indicating broader economic vulnerabilities in the region.