SoftBank Group is working to raise more than $11 billion through high-yield debt, commonly known as junk bonds, to fund its growing stake in artificial intelligence assets including OpenAI. As bond issuance, Arm share-collateralized loans, and other financing channels advance in parallel, the conglomerate's leverage is climbing, drawing market scrutiny over rising funding costs and the mounting pressure to secure profitable exits.

According to sources cited by Bloomberg on September 21, the offering includes $10 billion in dollar-denominated bonds and €1 billion (approximately $1.14 billion) in euro notes. A portion of the proceeds will back SoftBank's additional investment in OpenAI, which is expected to close next month, with bond pricing potentially set by Thursday. SoftBank has already raised nearly $15 billion in the bond market this year, ranking among the largest high-yield issuers since 2026.

Meanwhile, market pricing for SoftBank's debt is showing clear strain. Yields on its dollar bonds maturing in 2031 climbed to 8.2% earlier this month, up sharply from a January low of 6.7%, while the cost of credit default insurance has also reached multi-year highs. With AI investment scale expanding, higher financing costs combined with uncertain asset-exit timing are simultaneously testing SoftBank's cash management

Over $11 Billion Junk Bond Offering Fuels Continued OpenAI Investment

The proposed issuance comprises $10 billion in dollar bonds across three tranches and €1 billion in euro notes across two tranches. Citigroup is serving as lead bookrunner and global coordinator for the dollar portion, with Goldman Sachs, JPMorgan, and Morgan Stanley acting as joint global coordinators. For the euro tranche, JPMorgan takes the lead bookrunner role, with Goldman Sachs and Deutsche Bank participating as coordinators.

SoftBank's total committed investment in OpenAI has approached $65 billion, steadily enlarging its financial exposure to the AI developer. In March, SoftBank arranged a $40 billion bridge loan to fund its additional OpenAI investment, and has since repaid $25.9 billion of the outstanding balance.

This bond sale signals that SoftBank continues to fund its OpenAI position through fresh debt. As individual investment sizes expand, the capital-occupancy period for AI assets and future exit arrangements are increasingly shaping SoftBank's own funding requirements.

Arm Collateral Loans Expand, Multi-Channel Financing Lifts Leverage

Beyond bond issuance, SoftBank is also broadening its asset-backed borrowing. According to Bloomberg, SoftBank recently sought to increase its margin loan secured by Arm shares by $5 billion to $25 billion, while also securing an additional $450 million in credit facilities, bringing related commitments to $6.5 billion.

Separately, sources indicate that Apollo Global Management is in talks to expand its loan facility to SoftBank by $3.6 billion to $9 billion, again supporting the OpenAI investment. SoftBank has also obtained an $11.87 billion loan, and earlier this year arranged a $10 billion facility collateralized by OpenAI equity.

From bonds to share-backed margin loans and OpenAI-equity-collateralized financing, SoftBank is tapping multiple routes to fund its AI ambitions. The growing array of financing tools means its balance sheet is increasingly sensitive to interest rates, credit spreads, and swings in the valuation of its AI holdings.

OpenAI IPO Delay Raises Both Funding Costs and Exit Pressure

Another challenge facing SoftBank concerns OpenAI's exit path. OpenAI CEO Sam Altman recently stated the company will not go public this year. This implies that after committing massive financing to OpenAI, SoftBank may lack a clear public-market exit channel in the near term, potentially extending the capital lock-up period.

Should OpenAI eventually list, SoftBank's equity stake would gain a clearer liquidity route; however, the postponed timetable means SoftBank must carry financing costs for longer while waiting for investment value to materialize.

At the same time, pricing for SoftBank's own debt has visibly deteriorated. Yields on its 2031 dollar bonds have risen approximately 150 basis points from their January low, with higher funding costs and wider credit spreads jointly increasing the debt burden.

For SoftBank, the core tension is shifting from "access to capital" toward "the cost of that capital and when AI investments will deliver returns." With OpenAI's IPO timeline still unclear, the size and pricing of the over $11 billion junk bond sale will serve as a key barometer for market participants gauging SoftBank's leverage levels and credit risk.