South Korea's Kospi Crashes Nearly 11% as Global Chip Sell-Off Deepens

South Korea's stock market suffered one of its steepest single-day declines in years on July 28, with the benchmark Kospi index closing down about 10.8% at 6,023.66 after falling as much as 11.3% intraday. The Korea Exchange activated a market-wide circuit breaker, halting trading for 20 minutes, as the index dropped below 6,000 for the first time since April. Samsung Electronics tumbled roughly 13% to 14% and SK Hynix fell nearly 15%, with the two chipmakers accounting for more than half of the Kospi's weighting, meaning selling in just two stocks overwhelmed the wider market. The rout was triggered by the blockbuster Shanghai debut of Chinese memory maker ChangXin Memory Technologies, whose shares surged sharply and stoked fears that Chinese firms could accelerate competition in DRAM and NAND chips. The pressure spread across Asia, with Japan's Nikkei 225 falling about 4% and Taiwan's Taiex sliding, while US chip names including Nvidia, AMD and Micron also declined. Traders attributed part of the move to profit-taking after a prolonged rally in AI-related stocks and growing doubts over stretched valuations.