SoftBank's $10B OpenAI Payout: Debt-Fueled Ambition Meets a 34% Share Rout

SoftBank funds $10B OpenAI stake via bridge loan, not cash; shares drop 34% in month as accounting risks loom.

Masayoshi Son has never been shy about his conviction in artificial intelligence. Last week, the SoftBank chief dismissed any talk of a market bubble as "blasphemy," insisting the technology's potential is "only the beginning." His actions are backing those words in the most expensive way possible. The Japanese conglomerate has just released the second tranche of its massive OpenAI bet — another $10 billion flowing through the Vision Fund 2.

What makes the move unusual is how it's financed. SoftBank is not dipping into its cash reserves. Instead, it is drawing down from a $40 billion bridge credit line arranged by a consortium of banks including JPMorgan, Goldman Sachs and Mizuho Financial Group. The unsecured facility runs until March 2027, by which time SoftBank must repay the debt through asset sales or new borrowings. The structure signals a deliberate, step-by-step accumulation of OpenAI exposure. Once all tranches are complete, SoftBank's total investment in the ChatGPT developer will approach $65 billion, securing a roughly 13 percent stake through preferred shares that automatically convert to common stock upon any future initial public offering.

Yet the financing itself is a moving target. Separate negotiations are under way for a fresh $10 billion loan, this time secured against the very OpenAI stake SoftBank is building. That plan hit a roadblock earlier because banks struggled to value a private company's shares. To revive the talks, SoftBank has dangled a personal guarantee — should the value of the OpenAI stake slide, the conglomerate itself will cover the shortfall. The same trio of JPMorgan, Goldman Sachs and Mizuho is expected to back that facility as well.

While the boardroom is alive with dealmaking, the stock market tells a far chillier story. SoftBank shares closed Wednesday at €31.35, down 14.58 percent over the past week and a staggering 33.82 percent over the last month. The annualized 30-day volatility sits at 110 percent — a level that screams investor jitters. The relative strength index of 39.7 hovers in weak territory, though it has not yet dipped into oversold conditions.

The accounting treatment of the OpenAI holding adds another layer of risk. SoftBank will mark the private start-up's value to market each quarter, meaning any theoretical change in its estimated worth hits the profit-and-loss statement directly. That could whip earnings around violently until a listing provides a real market price. For now, the volatility in SoftBank's own shares mirrors the uncertainty embedded in its flagship asset.

The timeline for the next payout is already set: October 2026 is the target for the third and final $10 billion tranche under the current plan. If OpenAI goes public before then, SoftBank can pull the trigger early. Between now and that date, the company must also figure out how to unwind the massive bridge loan. The personal guarantee offered to banks may grease the wheels for the next $10 billion credit line, but it does not eliminate the underlying risk — only shifts it onto SoftBank's own balance sheet.

With more than $60 billion already plowed into OpenAI and related infrastructure projects such as the Stargate data center, Son's AI crusade leaves little room for half-measures. The market, meanwhile, continues to vote with its feet, punishing the stock even as the debt-fueled strategy accelerates. The next few weeks, as the October tranche approaches, will test whether the banks share Son's conviction — or share the market's unease.