KOSPI Sinks 10% as Samsung and SK Hynix Fall 12% in AI Selloff

- Trading suspended after foreign investors trigger selloff in semiconductor stocks - Market volatility driven by international shift away from AI-focused tech shares On 2026-06-23, Cryptopolitan reported that on June 23, 2026, South Korea’s KOSPI stock index plunged nearly 10%, prompting a trading suspension as foreign investors rapidly sold AI-driven semiconductor stocks such as Samsung Electronics and SK Hynix. The sharp losses followed months of speculative gains and highlighted volatility in Korea’s tech-heavy equity market, even as demand for AI infrastructure remained robust. According to Cryptopolitan on June 23, 2026, the KOSPI’s nearly 10% intraday drop led stock exchange officials to halt trading, and shares of Samsung Electronics and SK Hynix, Korea’s leading semiconductor producers, each tumbled over 12% during the session. Foreign funds actively reduced exposure to concentrated AI semiconductor positions, and this sudden reversal erased previous gains from a sustained rally earlier in the year. Cryptopolitan further reported on June 23, 2026, that the selloff coincided with Samsung Electronics’ announcement of the industry’s fastest Universal Flash Storage 5.0 solution, which set new benchmarks for speed in on-device AI applications. According to Samsung’s newsroom on the same day, UFS 5.0 addresses storage bottlenecks for large language model workloads and underscores ongoing demand for advanced AI hardware. However, the timing of this product launch and the market downturn emphasized how international investor flows can overshadow strong business fundamentals and amplify volatility. In addition, market analysts cited by Cryptopolitan on June 23, 2026, noted that Korea’s equity market is vulnerable because of its heavy weighting in a small group of technology stocks supplying global AI infrastructure. Rapid shifts in foreign capital therefore intensified volatility through this concentration, and the June 23 selloff showed the outsized influence of international flows on valuations even as prospects for AI development stayed positive. According to Cryptopolitan on June 23, 2026, Samsung Electronics and SK Hynix closed the session with more than 12% declines, while the KOSPI’s nearly 10% drop triggered automatic trading halts to contain losses. These events reflected a global shift away from AI-focused technology shares, directly impacting Korea’s semiconductor sector and reinforcing the market’s susceptibility to rotational flows.