SoftBank seeks $10B loan to refinance OpenAI investment as lenders question AI valuations

SoftBank is trying to borrow $10 billion using its OpenAI stake as collateral, reviving margin loan discussions that previously stalled when lenders balked at the valuation of shares in a private company. The move is part of a broader refinancing scramble to address a $40 billion bridge loan facility that matures in March 2027, less than a year after SoftBank originally secured it.

The debt stack behind SoftBank’s AI ambitions

SoftBank secured a $40 billion unsecured bridge loan in March 2026, primarily to fund a $30 billion follow-on investment in OpenAI. SoftBank’s cumulative commitments to OpenAI now total roughly $65 billion, representing about a 13% stake in the AI company.

The $10 billion margin loan would be backed by SoftBank’s OpenAI shares, but previous attempts to arrange this kind of financing were scaled back because banks struggled to agree on how to value privately held shares that can’t be easily sold on an open market. To sweeten the deal, SoftBank has reportedly offered a corporate guarantee on the margin loan.

Bond sales and the credit rating problem

SoftBank is also exploring a bond offering valued between $10 billion and $20 billion, potentially denominated in both US dollars and euros. As of late August, those discussions were still ongoing.

S&P currently rates SoftBank at BB+ with a negative outlook, which places it firmly in junk territory. SoftBank’s bridge loan maturing in March 2027 creates a hard deadline.

What illiquid collateral means for AI valuations

Banks lending against publicly traded shares can mark them to market daily and issue margin calls if values drop. With private shares, there’s no real-time price discovery. Lenders are essentially being asked to accept a valuation based on the most recent funding round, which may or may not reflect what the shares could actually fetch in a sale.