Korean stocks rebound sharply, triggering buy-side sidecar mechanism; Samsung and SK Hynix close up over 5%

South Korean stocks rebounded Wednesday, recovering ground lost after the previous session's sharp selloff, as concerns over AI capital expenditure eased and the semiconductor sector surged, with the Korean won strengthening against the U.S. dollar in tandem. The benchmark KOSPI closed at 5,735.66, up 182.92 points, or 3.29%, after touching an intraday high of 5,816.43. The sharp rally prompted the Korea Exchange to trigger a buy-side sidecar shortly before 11 a.m., when KOSPI 200 index futures gains exceeded 5%, halting program trading for five minutes. It was the first time the mechanism had been triggered in two months. Large-cap heavyweight stocks rose broadly, led by the semiconductor sector. Market bellwether Samsung Electronics closed up 5.67% at 223,500 won, while chip leader SK Hynix gained 5.81% to 1.29 million won. Power equipment maker LS Electric surged 7.02% to 166,100 won after reporting better-than-expected third-quarter results, buoyed by robust demand from AI data centers.