SoftBank Group shares fell more than 13% in Tokyo on September 14 after the heads of Anthropic and OpenAI called for slower AI development for safety, raising fresh doubts about the value and timing of the Japanese investor’s AI bets.

The drop was SoftBank’s biggest since late June and left the stock about 30% below its June peak.

Investors are also weighing AI competition, hacks, and other reported unsanctioned activity.

SoftBank said its total investment in OpenAI could reach nearly US$65 billion by October.

OpenAI co-founder Sam Altman also said the startup would not go public in 2026, potentially making SoftBank wait longer to monetize a large private holding.

The group also plans to raise more debt through a 1 trillion yen (US$6.49 billion) retail bond and a US$10 billion loan tied to OpenAI shares.

It plans to use the funding for its AI push and acquisitions such as ABB Robotics and DigitalBridge.

That leaves investors weighing longer-term returns from private AI stakes against SoftBank’s near-term borrowing needs.

🔗 Source: Bloomberg

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