Korea Exchange sees erratic trading in first after-hours session

South Korea’s stock exchange opened its doors after dark for the first time on September 14, and the results were, well, chaotic. The Korea Exchange’s debut after-hours session drew roughly 1.8 trillion won (about $1.33 billion) in turnover, a respectable showing that also happened to trigger 1,637 volatility interruption halts. For context, a normal daytime session sees around 400. The four-hour window, running from 4 p.m. to 8 p.m. local time, was designed to let Korean investors react to global market developments outside traditional hours. Retail investors ran the show The most striking detail from the inaugural session: retail investors accounted for 93% of the total turnover. Foreign investors contributed just 3.9%, and institutional participation was essentially a rounding error. The session saw 72.24 million shares change hands across 2,501 stocks, covering over 95% of listed KOSPI and Kosdaq names. That breadth is a significant expansion compared to the previous Nextrade system, which offered far fewer eligible securities. Some of the price action was dramatic. Shares of Hanwha Galleria surged 14.6% before pulling back. The 1,637 volatility interruption activations represe...