The KOSPI index experienced a sharp surge during early trading on the 12th, triggering a "buy sidecar" mechanism. This measure temporarily suspends program buy quotes to stabilize the market during periods of extreme volatility. The sudden rally was driven by positive investor sentiment following a peace agreement between the United States and Iran. This geopolitical breakthrough led to a rapid increase in stock prices across the Korean market. Market participants reacted quickly to the news, pushing the index upward in the opening hours. The sidecar was activated as a regulatory safeguard to prevent an uncontrolled spike. Trading continued under these stabilized conditions as the market processed the diplomatic development.