S Korea triggers 'sidecar' halt, KOSPI slumps about 8%

South Korea's stock market operator issued a sell-side halt early Thursday as the KOSPI index fell nearly 8%, mirroring a tech-sold-off on Wall Street driven by persistent US inflation data. The automatic five-minute suspension on program sell orders occurred after significant losses in index futures, a sudden cooling mechanism activated as the KOSPI entered its seventh consecutive day of decline, the longest losing streak since September 2024.

The benchmark Kospi index dropped 7.7% to 5,548.78, marking a drop below its all-time high reached in June. Tech giants Samsung Electronics and SK Hynix saw the steepest declines, with shares falling 9.05% and 11.06%, respectively. Other notable losers included LG Energy Solution, Hyundai Motor, and Kia Corp. While 90 stocks saw gains, 768 declined among the 889 traded.

Foreign investors were net sellers, worth 355.6 billion won. The South Korean won strengthened to 1,339.5 per dollar. In money markets, December futures on three-year Treasury bonds rose 0.12 point to 103.00, while the yield on a 10-year bond fell by 2.1 basis points to 4.224%.