TradingKey - On August 21, Japanese and South Korean stock markets opened lower as overnight declines in US equities and rising oil prices sparked inflation concerns, dampening market risk appetite. South Korea's KOSPI index opened down 1.35% at 6,759.95 points, before narrowing its drop to 1.12% to trade at 6,775.63 points; Japan's Nikkei 225 Index (JPN225) opened down 1.11% at 65,484.91 points, before trimming its loss to 0.84% to stand at 65,663.18 points.

Source: TradingView

Among South Korean individual stocks, SK Hynix rose 1.12% to trade at 1.71 million won (approx. $1,235); Samsung Electronics fell 0.18% to 270,500 won.

In the Japanese market, Kioxia gained 1.17% to trade at 53,550 yen (approx. $337); SoftBank Group slipped 0.71% to 5,349 yen.

The weak overnight performance of US equities served as a major factor weighing on Asian markets. The impact of US Treasury Secretary Bessent's previous bond market intervention gradually faded, while Trump's sanction threats against Iran further drove up oil prices, reigniting market concerns that rising energy prices could exacerbate inflationary pressures.

The three major US stock indices closed lower across the board. The Dow Jones Industrial Average fell 1.32% to 52,759.21 points, tumbling 703.84 points in a single day; the S&P 500 Index dropped 0.87% to 7,641.16 points; the Nasdaq Composite Index fell 1.00% to 26,067.17 points, with the Nasdaq 100 Index moving lower for a fifth consecutive trading session.

On August 21, according to South Korean media reports, SK Hynix is weighing a large-scale investment plan, considering investing tens of trillions of won to build a memory chip production base in Miyagi Prefecture in northeastern Japan. If implemented, this would mark the first instance of a South Korean semiconductor company establishing a large-scale local production facility in Japan.

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