Samsung and SK Hynix Face an Earnings Test After South Korea's AI Sell-Off

South Korea’s KOSPI is under pressure heading into the fourth quarter of 2026 as volatility spills over from global AI stocks—and its heavy exposure to Samsung Electronics and SK Hynix is intensifying the swings. Over the first three weeks of October, the Korea Composite Stock Price Index fell more than 20%, reversing a trend that had lifted the benchmark 111.49% to its year-to-date peak in June. The article says Samsung accounts for roughly part of the index’s weight alongside SK Hynix, with semiconductors responsible for about 50% of KOSPI market capitalization. SK Hynix has lost 34.14% in the past month and Samsung is down 18.97%. Still, the KOSPI remains up 61.76% versus January 2026, and Finance Minister Lee Hyoung-Il reiterated confidence that demand-supply gaps will support growth into 2027.