As AI investments increasingly link the fates of US tech giants with those of South Korean memory chip makers, the correlation between Wall Street tech stocks and the South Korean stock market is growing stronger. The 60-day correlation between the South Korean KOSPI index and the Nasdaq 100 recently rose to around 0.50, the highest level since 2021. This increasingly close relationship reflects the growing dominance of Samsung Electronics and SK Hynix, which together account for more than half of the KOSPI's weighting. "This increased correlation is because the index has evolved into a semiconductor index," said Rolf Bulk, an analyst at Futurum Group. The scale and volatility of the recent surge in South Korean chip stocks have prompted global investors to view the South Korean market as a key indicator of broader AI trading trends. However, analysts caution that the movements of South Korean and US tech stocks are moving in tandem, rather than one consistently outperforming the other. This increasingly close correlation also carries risks. Industry veterans point out that the increased correlation undermines the diversification benefits investors previously sought by holding both US and South Korean stocks simultaneously. Bulk stated, "The South Korean stock market can no longer serve as a hedge against the risks of US tech stocks. Since half of the index's weighting is tied to a single cyclical theme, the South Korean market will be more severely impacted than most other markets should hyperscale cloud service providers cut capital expenditures."
