KOSPI Drops 7% Amid Hot US CPI Data and AI Sector Doubts

The Korea Composite Stock Price Index (KOSPI) opened sharply lower, sliding 7.28% to 5,571.27 by 10:13 a.m. Seoul time, extending a six-session losing streak and falling roughly 40% from its June 19 peak. This decline was driven by hotter US inflation data, where the September Consumer Price Index (CPI) reached 3.7% (above the expected 3.6%), and growing AI skepticism, which also weighed on US stocks like the S&P 500 and Nasdaq Composite. Samsung Electronics fell 6.03% and SK Hynix dropped 7.61%, while foreign investors sold a net 285.6 billion won. The inflation surprise revived fears of another Federal Reserve (Fed) rate hike at its October 27 and 28 meeting, potentially increasing borrowing costs for AI data center financing.