SoftBank Group's stock plunged 8.1% to ¥5,360 on Wednesday as investors reacted to a combination of a looming corporate bond issuance and a bond-market driven rout across Japan's AI and technology sectors.
The immediate catalyst at the market open was a Nikkei report that the group is preparing an offering of about ¥1 trillion in seven-year bonds aimed at retail investors. That deal, if executed as described, would be the largest retail corporate bond offering ever by a Japanese company. Proceeds from the planned sale are intended for AI-related investments, intensifying scrutiny over SoftBank's already sizable debt position.
At the same time, a broader rise in sovereign yields intensified pressure on equities. Japan's 10-year government bond yield climbed to its highest level since 1996 amid market speculation that the Bank of Japan could move toward policy tightening as early as September. In the United States, 30-year Treasury yields also moved to a 19-year peak. Rising yields have fed concerns about the cost of capital for long-duration projects.
Analysts pointed to a direct link between higher borrowing costs and the viability of capital-intensive AI infrastructure spending. That dynamic places valuation pressure on companies whose investment stories rely on extended, heavy-capital deployments - a category that includes SoftBank.
There was little relief elsewhere in Tokyo. The Nikkei 225 dropped for a second consecutive session, sliding as much as 3.1% in early trading, while the broader Topix index fell as much as 2.8%. The selloff hit electronics firms and financial stocks hardest, contributing to the wider market decline.
The market reaction reflects two intertwined concerns: a funding move that would materially increase corporate debt targeted at retail investors, and a macro environment in which higher sovereign yields raise the cost of funding long-term technology investments. Together, those factors help explain the sharp move in SoftBank's share price and the contemporaneous weakness across Japan's equity indices.
Market snapshot referenced in reporting: Nikkei 225 - slid as much as 3.1% in early trading; Topix - down as much as 2.8%; Japan 10-year government bond yield - highest since 1996; U.S. 30-year Treasury yield - reached a 19-year high.