SoftBank Group has spent the year levering up one of the largest bets in its history, and on September 9 it laid out the next step in that chain: repaying early the full remaining balance of the bridge loan that helped fund its investment in OpenAI.
The Japanese conglomerate said it will pay off $25.9 billion on September 15, clearing the balance of the $40 billion unsecured bridge loan it signed in March. That loan, arranged to finance SoftBank’s OpenAI stake, was the company’s largest single dollar borrowing on record, and the early repayment closes it out months ahead of schedule.
What comes next is a stack of replacement funding drawn from three directions. The first is a 1 trillion yen retail bond, about $6.3 billion, priced on September 4 with a seven-year maturity and a 4.75 percent coupon. That coupon is SoftBank’s highest on a straight bond in 17 years, and the sale is the largest retail bond issue in Japanese corporate history, aimed squarely at individual investors rather than the institutional funds that usually buy SoftBank debt.
The second leg is a high-yield bond offering of between $10 billion and $20 billion, denominated in dollars and euros, with a New York roadshow set to begin around September 14. A deal of that size would rank among the larger junk-bond sales of the year and would test how much appetite credit investors have for a borrower whose story is now tied to a single private AI company.
The third leg is already in place: a $10 billion margin loan extended in August by Goldman Sachs, JPMorgan, Mizuho, Apollo and Sumitomo Mitsui, collateralized by SoftBank’s OpenAI preferred shares. A second loan of the same size is still under discussion, according to people familiar with the talks. Margin loans of this kind are secured against a volatile, privately priced asset, which makes their terms unusually sensitive to the next valuation OpenAI assigns itself.
Put together, the structure replaces short-term bridge debt with longer-dated bonds and asset-backed borrowing. Analysts read it as a way for SoftBank to stretch its OpenAI exposure without selling the stake, using retail investors, bond funds and margin lenders in place of the banks that wrote the original bridge. The cost of that flexibility is visible in the numbers: a 4.75 percent retail coupon and high-yield pricing that reflects the risk investors are being asked to take.
The scale of the underlying position is what makes the financing notable. By October, SoftBank’s cumulative investment in OpenAI is expected to reach roughly $65 billion. OpenAI’s most recent internal valuation, used in connection with its latest funding discussions, stands at about $852 billion, according to people familiar with the matter. Those two figures, taken together, describe a company whose balance sheet has become a concentrated wager on one name.
That leaves SoftBank’s fate unusually tied to a single private company. A margin loan backed by OpenAI preferred shares works only as long as the value of the collateral holds; a sharp repricing of OpenAI’s equity would press the same lenders SoftBank is now courting for a second tranche. The structure works in calm markets and becomes unforgiving in a downturn, which is precisely the scenario bond investors worry about.
Founder Masayoshi Son has made concentrated bets his signature, from the early backing of Alibaba to the Vision Fund’s splurge on unprofitable startups. This one is among the most concentrated he has assembled: the company is effectively financing its stake in an unlisted artificial-intelligence firm with retail debt and margin loans, stacking debt on top of debt while the underlying asset itself is still privately priced.
The financing also reflects OpenAI’s own insatiable appetite for capital. The startup has raised tens of billions of dollars to fund data centers and model training, and its investors have had to find ever larger pools of money to keep pace. SoftBank has positioned itself as OpenAI’s most important financial partner, leading its funding rounds and anchoring the infrastructure ventures the two companies have announced together. The bridge loan was the tool that let SoftBank move first and fast; the refinancing is the tool that lets it stay in without selling down.
The size of the figures involved has drawn scrutiny from credit analysts, who note that SoftBank’s debt load has historically moved with its appetite for concentrated bets. The company survived a near-collapse around its WeWork and Vision Fund losses, and its recovery has been driven in part by the AI rally that lifted the value of its holdings. Rebuilding that exposure on borrowed money invites the comparison, and some analysts have warned that the retail bond and margin structure reintroduces risks SoftBank spent years unwinding.
Whether the bet pays depends on OpenAI’s next valuation marks and its eventual path to a public listing. For now, the September 15 repayment closes one chapter of the financing and opens another, in which a wider set of creditors than ever is exposed to the price of a single private AI company. Son has staked the company’s financing future on OpenAI the same way he has staked its capital, and the two bets now rise and fall together.
