South Korea's KOSPI index surged past 7,100 points on Wednesday before retreating to close at 6,797.70 [2].
The volatility reflects a tug-of-war between optimism over next-generation AI hardware and anxiety regarding upcoming quarterly reports from major U.S. technology firms.
The market opened at 7,052.09 points, representing a 4.51% increase from the previous day [4]. The rapid ascent triggered a buy-side "sidecar" — a volatility cooling mechanism — as the index climbed to a peak intraday level of 7,166.00 points [5].
Journalist Yoon Tae-in of YTN News said the surge was driven by reports of Nvidia's Vera Rubin production and supply boosts, which caused U.S. semiconductor stocks to jump. The KOSPI saw an intraday rise of over six% during this peak [1, 3].
Samsung Electronics shares rose more than six% to approximately 260,000 won [6]. SK Hynix also saw significant movement, recovering to 200,000 won during the session before closing around 183,000 won [7].
Despite the early momentum, the index gave back most of its gains toward the end of the session. The final closing price of 6,797.70 [2] reflected a net intraday rise of 0.74%, or 49.75 points [3].
Trading data showed a divergence in investor behavior. Foreign investors were net buyers, while domestic individuals, and institutions acted as net sellers [8].
Analysts said that cautious sentiment prevailed as investors awaited major tech earnings from the U.S. This hesitation, combined with shifting supply-demand dynamics, contributed to the late-session decline [1].
“KOSPI surged past 7,100 points after the opening, triggered a buy-side sidecar”
The KOSPI's sharp reversal demonstrates the high sensitivity of the South Korean market to US AI chip developments and the influence of foreign capital. While news of Nvidia's Vera Rubin production provided a catalyst for growth, the subsequent drop suggests that investors are unwilling to maintain peak valuations without confirmed earnings data from the US tech sector.
