SoftBank Group executives have begun talks with investment banks about a bond offering that could raise between $10 billion and $20 billion, according to people familiar with the matter, part of an effort to refinance the Japanese conglomerate’s growing investment in OpenAI. The discussions, reported on Aug. 26, are at an early stage, and the size and timing of any sale could change, the people said.
A sale of that size would rank among the largest corporate bond issuances ever brought to market by a Japanese company. The proceeds would help fund and refinance SoftBank’s exposure to the ChatGPT maker, whose capital needs have expanded with each generation of its frontier models. SoftBank has emerged as one of OpenAI’s most important backers, participating in successive funding rounds as the company’s valuation has climbed into the trillions of dollars.
SoftBank has long used debt to finance outsized bets. Under founder Masayoshi Son, the company borrowed heavily to fund the Vision Funds, the world’s largest technology investment vehicles, and it has poured tens of billions of dollars into AI companies in recent years, from chip designers to data-center operators. The OpenAI stake is now one of the largest single positions on SoftBank’s books, and refinancing it through the bond market would spread the cost across fixed-income investors rather than forcing SoftBank to sell other assets or tap its own cash.
The move comes at a delicate moment for both companies. OpenAI is widely expected to pursue an initial public offering, and its capital requirements show no sign of slowing: training the most advanced models requires clusters of graphics processors that cost billions of dollars, and the company has committed to building its own data centers in partnership with other investors. SoftBank’s willingness to write large checks has made it a cornerstone of OpenAI’s financial structure, including the Stargate venture with Oracle and other partners announced in early 2025 to build AI infrastructure in the United States.
For bond investors, the offering would be a bet on SoftBank’s creditworthiness as much as on OpenAI’s prospects. The conglomerate’s balance sheet has healed considerably since the WeWork episode and the Vision Fund losses of the early 2020s, and its shares have climbed as AI enthusiasm has lifted its portfolio. Analysts said a successful sale would signal that fixed-income markets are willing to finance the AI build-out at a scale once reserved for sovereigns and the largest industrial companies.
The economics of the refinancing depend on interest rates and on SoftBank’s access to cheap yen funding, a tool the company has used aggressively in the past. Japanese interest rates remain low by global standards, and domestic investors have shown steady appetite for large corporate issues. The main risk, analysts said, is concentration: SoftBank’s fortunes are now tightly tied to OpenAI’s execution, and any stumble in the AI company’s path to profitability would be felt directly in SoftBank’s stock and, eventually, in the cost of servicing any new debt.
People familiar with SoftBank’s thinking said the company sees the bond market as a way to match its long-term AI commitments with long-term financing, rather than relying on short-term borrowings that must be rolled over. The company has also signaled it wants to keep dry powder for additional investments, both in OpenAI and across the wider AI supply chain, from power producers to chip packaging plants.
The discussions also reflect a structural shift in how OpenAI is financed. In its early years the company relied on equity from a small circle of investors and on cloud credits from Microsoft. The scale of its current build-out, which includes campuses of data centers and long-term power contracts, has pushed the company toward more complex arrangements, including debt-like securities sold to institutional investors. SoftBank, as the largest financial backer outside that circle, has become a lender of first resort for parts of the project, and the bond market would let it share that role with public investors. People familiar with the matter said the talks are part of a broader review of SoftBank’s AI portfolio, in which the company is weighing which stakes to hold, which to refinance, and which to sell.
A final decision has not been made, the people said. Bankers have been asked to model several structures, including conventional bonds and securities linked to SoftBank’s share price, and to test investor appetite in the United States, Japan, and Europe. The outcome will be watched closely by the broader AI financing market, where the phrase “capital intensity” has become the polite way of saying that the industry’s funding needs have no obvious ceiling. For a company that built its reputation on placing big bets ahead of the crowd, the bond market is the next table where SoftBank intends to sit down.
