Shares of the Southern KOSPI ETF (03121) fell sharply in late trading, dropping nearly 4% before the close. As of the latest update, the fund declined 3.85% to HK$6.495, with turnover reaching HK$18.41 million. The selloff comes as major players in the artificial intelligence sector, including OpenAI, Anthropic, and SpaceX AI, have jointly called for a slowdown in AI development timelines.

Adding to the market jitters, OpenAI CEO Sam Altman confirmed the company would suspend its IPO plans until 2026. Market analysts note that while the long-term AI growth narrative remains intact, near-term shifts in expectations could alter the valuation trajectory across computing power, hardware, and application segments.

The impact was felt across South Korea's benchmark index, with the KOSPI closing Monday down 3.26% at 6684.37 points. Among heavyweights, SK Hynix plunged 6.34%, while Samsung Electronics dropped 4.04%.

In a notable development, the South Korean stock market officially launched after-hours trading on September 14, aiming to better compete with the liquidity of major U.S. exchanges and broaden trading opportunities for investors.