South Korea’s KOSPI index briefly halted trading on Wednesday after sliding more than 5% in a sharp reversal, with heavy losses in semiconductor stocks such as SK Hynix and Samsung Electronics driving the decline.
The benchmark gauge fell as much as 6.4% before paring losses to trade down 4.53% at 6,558.41, triggering a temporary trading suspension under the market’s automated circuit-breaker mechanism. The halt followed a six-day winning streak that had lifted the index more than 2% on Tuesday.
SK Hynix shares dropped 6.56%, while Samsung Electronics slid 5.40%, extending losses for the two South Korean chip giants. U.S.-listed ADRs for SK Hynix fell 9.2%, reflecting the broader selloff in the sector. Japanese memory chipmaker Kioxia tumbled 7.73%, while Micron Technology declined 7%. Nvidia, a key beneficiary of AI-related demand, shed 2.3%.
The Philadelphia Semiconductor Index, which tracks 30 major U.S.-listed chip stocks, plunged 5.6%—its worst session since early July—amplifying the global semiconductor rout. The decline underscored investor unease over the sustainability of recent gains in AI-related equities.
Market participants cited profit-taking after a strong rebound as a key factor behind the reversal. Concerns also persisted over whether capital expenditures by Big Tech on AI infrastructure and data centers would deliver timely returns. High-bandwidth memory demand, a critical component for AI data centers, has been a focal point for investors evaluating the sector’s growth trajectory.
Rising U.S. Treasury yields added pressure, with the 30-year bond yield reaching its highest level since 2007 and the 10-year yield approaching 4.72%. Higher yields increase the discount rate applied to future corporate earnings, disproportionately affecting high-growth technology stocks.
The selloff in South Korea’s market and broader semiconductor space reflects broader risk-off sentiment across global equities, with investors reassessing valuations amid shifting macroeconomic conditions.
