Memory-Chip Selloff Spreads to Seoul, Driving the Kospi Down About 5 Percent

South Korea's benchmark index reversed a two-day rally on Thursday. The Kospi fell about 5 percent at its worst point and the exchange activated its sidecar mechanism, which suspends program sell orders. SK Hynix fell more than 7 percent and Samsung Electronics also declined, while foreign investors turned net sellers of more than 500 billion won after buying in recent sessions.

The selling began with results reported in New York. SanDisk reported revenue of $8.96 billion for its fiscal fourth quarter, but guided first-quarter revenue to a midpoint near $10.55 billion, below the roughly $10.8 billion analysts expected. Memory shares had already fallen through late July. SanDisk was down about 45 percent over the previous month, and the planned initial public offering of the Chinese memory maker CXMT added further pressure.

The Israeli business daily Globes covered the same session from an Israeli perspective, reporting declines across Asia led by Korea and stability in oil prices and on Wall Street, alongside more than $1 billion of combined market value lost overnight by the Israeli-linked companies Taboola and SolarEdge.

United States indexes moved in opposite directions on Wednesday. The Dow Jones Industrial Average rose about 0.5 percent while the Nasdaq Composite fell about 0.8 percent. That divergence indicates capital leaving artificial-intelligence hardware stocks rather than leaving equities altogether. Korean retail investors, many of whom bought the memory stocks as prices rose, are absorbing the concentrated losses.