On 15 October, the Nikkei Average fell sharply below the key ¥65,000 level, as credit concerns spread following a plunge in CoreWeave bonds. Investors are expected to shift funds into defensive stocks while assessing the earnings of individual companies.
In Tokyo trading on 15 October, the Nikkei Average fell sharply, with semiconductor-related stocks also suffering steeper declines. The previous day’s US CPI and an emerging US cloud company, along with the sharp drop in CoreWeave (CRWV) bond prices, have been cited as factors behind the plunge. CoreWeave pioneered the leasing of data centres equipped with AI semiconductors to neo-cloud companies, and reports on 14 October concerning the maturity of its bonds fueled credit concerns. This triggered selling in US technology stocks, with the impact spreading to the Japanese market.
The focus now is whether the credit concerns sparked by CoreWeave will subside. Equity markets had been testing a recovery amid rising interest rates in Japan and the United States, but the sharp drop in corporate bonds has delivered a shock and increased uncertainty in the markets. Kioxia Holdings, which was popular with individual investors in the first half of 2026, also saw its share price decline, while the swelling balance of outstanding margin purchases is contributing to stop-loss selling.