South Korea's KOSPI falls 2.7%, biggest drop in two weeks

South Korea's stock market suffered a severe downturn on Monday, with the Korea Composite Stock Price Index (KOSPI) closing sharply lower by 2.70% at 6,889.74 points.

The decline was driven by a combination of bearish factors, including a catch-up effect following the extended Chuseok holiday and persistently high U.S. Treasury yields. The sell-off erased gains from the previous four consecutive trading sessions and marked the largest single-day percentage drop since September 14.

The KOSPI fell steadily throughout the session, ultimately losing 191.18 points. The index had recently reached a two-month high but reversed sharply after the opening bell.

Tech Giants Lead the Decline

Technology stocks bore the brunt of the sell-off:

• Samsung Electronics plunged 5.43%
• SK Hynix tumbled 5.05%

Analysts noted that rising global bond yields are putting significant pressure on high-valuation tech growth stocks.

"Triple Whammy" in Financial Markets

South Korea's financial markets experienced a clear "triple whammy" of falling stocks, a weakening currency, and rising bond yields:

• The Korean won weakened notably against the U.S. dollar
• The three-year Korean government bond yield rose, driven by risk aversion and tightening expectations

External Factors and Holiday Gap

South Korean financial markets were closed last Thursday and Friday for the local Chuseok holiday. During that period, global markets—particularly U.S. tech stocks—experienced significant volatility. Upon reopening Monday, the market rapidly absorbed the accumulated external risks that had built up during the holiday break.

Macroeconomic Context

Recent global macroeconomic conditions have been shaped by:

• Persistent inflation
• Expectations that major central banks will maintain higher interest rates for longer ("Higher for Longer")

These factors have kept government bond yields elevated, directly increasing borrowing costs and valuation discount rates for major tech companies. This has accelerated capital outflows from both foreign and domestic institutional investors, particularly from the semiconductor sector's two leading firms.

Outlook

Market analysts widely expect that the near-term trajectory of South Korean stocks will remain highly dependent on the Federal Reserve's hawkish policy stance and changes in global macro liquidity. Whether the semiconductor sector can stabilize will be a key factor in determining if the KOSPI can rebuild a bottom.