Inside one of the wildest months in South Korea's stock market history

South Korea’s Kospi ended July with a record rally, gaining 18% in a single day on Friday, even as it finished the month down 22%—down about 30% from its June peak. Samsung Electronics and SK Hynix led the rebound, rising 27% and 30%, respectively, as optimism returned to AI memory stocks after a tech lift on Wall Street. The Kospi has become a key readout for global AI trading because it’s chip-heavy and dominated by memory giants. Yet the surge also increased concentration risk: investors piled into Samsung and SK Hynix, and demand for leveraged single-stock ETFs amplified swings. Those products, launched in May, forced rebalancing amid selloffs. July’s 22% drop was the worst since October 2008, and analysts said “short-term distortions” outweighed fundamentals as memory shortages persist for years.