KOSPI Closes Down Over 3% as SK Hynix and Kioxia Both Plunge 7%, SoftBank Drops Nearly 6%

TradingKey - KOSPI Plunges 5%, Triggering Sidecar Mechanism; SK Hynix and Kioxia Both Collapse 7%.

During the Asian trading session on October 30, Japanese and South Korean stock markets traded lower throughout the day, presenting a broad decline marked by sharp volatility and steep losses in South Korean stocks, alongside pullbacks in Japanese stocks under pressure from high levels. South Korea's KOSPI index plunged over 5% intraday, triggering a sell-side sidecar mechanism. Losses narrowed late in the session as institutional and domestic buyers stepped in, with the index ultimately closing down 3.48% at 5,730.74 points.

The two major heavyweights also strengthened toward the close. Industry leader Samsung Electronics closed down 3.02%, falling below the 230,000 mark to end at 225,000 won; SK Hynix tumbled 7.08% at the close, losing the 1.5 million mark to finish at 1,418,000 won.

KOSPI index chart, Source: TradingView

The Nikkei 225 Index ended down 2.12% at 63,289.89 points. Two major heavyweights suffered significant drops, with Kioxia plunging 7.14% to close at 13,470 yen and SoftBank falling 5.96% to close at 4,481 yen.

A series of tech giant earnings reports released in US stocks was the direct trigger for today's bloodbath in Asian semiconductor and AI supply chain stocks. Whether Amazon (AMZN) and Alphabet (GOOG) can stem their decline and rebound at key support levels during regular US trading hours later today will directly determine whether Asian tech stocks can achieve a technical recovery next Monday. If US stocks remain stable and the uncertainty surrounding the November 3 US midterm elections settles, Japanese and South Korean stock markets are expected to shake off the earnings CapEx panic and return to a fundamentals-driven track.