For fund managers across the major financial centers, the pre-market routine now frequently includes a close watch on South Korean equities. Once a less central focus for many global investors, Korea’s substantial $4 trillion equity market has become an early indicator of shifting risk appetites, particularly as the performance of companies like Samsung Electronics Co. and SK Hynix Inc. sends ripples through semiconductor stocks worldwide. This evolution has prompted a reevaluation of investment strategies, with figures like JPMorgan Asset Management’s chief Asia market strategist noting he has only this year delivered a presentation on Korea to his global team, despite 14 years in the role. Traders in Japan are similarly integrating the Kospi Index into their daily surveillance, underscoring a sentiment captured by Hani Redha, a London-based portfolio manager at PineBridge Investments, who recently remarked, “We are all Korean investors now.”
The escalating influence of the Korean market, however, arrives with an inherent characteristic: increased volatility. The Kospi has emerged as one of the most volatile major benchmarks globally, a trend amplified by leveraged trading activities. The recent US listing of SK Hynix has further extended Korea’s market reach into Wall Street, leading to a dynamic where sentiment-driven trading in Seoul increasingly dictates the global tone for AI-related stocks around the clock. This interconnectedness means that a turbulent session in Korea, such as one observed after a long weekend when global chip peers experienced a sell-off due to renewed doubts over capital expenditure following a Chinese AI startup breakthrough, can immediately impact international markets. Redha, for instance, begins his day by examining Seoul for insights into the AI trade, shifting his attention to SK Hynix’s American depositary receipts and Korea-focused exchange-traded funds in New York once the Korean market closes, effectively monitoring the situation almost 24 hours a day.
This intricate linkage was strikingly evident recently when a local selloff in Korea, fueled by skepticism concerning future AI demand, triggered a nearly 9% decline in the Kospi. This weakness subsequently spread to Wall Street, where SK Hynix’s US-listed shares fell by 9.3%, dragging down other major chip stocks. The tightening correlation is also observable in data, with the 60-day correlation between the Kospi and the Nasdaq 100 climbing to 0.46, nearing a two-year high and almost triple its five-year average of 0.16. Ivan Feinseth, chief investment officer at Tigress Financial Partners in New York, emphasizes this shift, stating that Korea has effectively become part of the same volatility ecosystem as Nasdaq and SOX, with SK Hynix, Samsung, and the Kospi now serving as a pre-market indicator for US AI and semiconductor risk. He concludes that the Asian country is no longer merely “a distant emerging-market side show.” 
The impact of Korean stocks appears even more pronounced during downturns. Data indicates that the Nasdaq 100 Index’s sensitivity to the Kospi during periods of Korean market weakness reached its highest level since 1990 on July 7. A similar measure for the MSCI World Index also recorded a four-year high earlier in the month. This heightened correlation extends to Japan, with the Nikkei 225 also showing a surge in its correlation with the Kospi. This development prompted Andrew Jackson, head of Japan equity strategy at Ortus Advisors, to add a Kospi chart for close monitoring earlier this year, a first in his more than two decades in the field. Herald van der Linde, head of equity strategy for Asia Pacific at HSBC Holdings Plc, confirms that Korea is now a topic in “all meetings,” while Tai Hui at JPMorgan Asset Management acknowledges the new emphasis on the Korean market.
Despite its burgeoning influence, the Korean market has experienced its own challenges. The Kospi Index has seen a 25% decline since its June peak, resulting in a $1 trillion market value reduction that could potentially temper its global clout. Both Samsung and SK Hynix, the country’s leading chipmakers, have each lost at least 30% of their value. Furthermore, a temporary halt on new listings of single-stock leveraged exchange-traded products by the country’s authorities may help to curb speculation and volatility. Nevertheless, the benchmark remains up 62% for the year, positioning it among the top global performers. Given the critical role of SK Hynix and Samsung Electronics in the global memory chip supply chain, the Korean market is likely to retain its position as a central barometer for global AI investment in the foreseeable future. Chisa Kobayashi, Japan equity strategist at UBS SuMi TRUST Wealth Management, suggests that this heightened volatility and influence from a relatively immature market with leverage-related swings represent “the new normal investors have to accept, as long as the AI rally continues,” acknowledging the difficulty such dynamics present when moves deviate from fundamental principles.
