SoftBank sells the largest high-yield bond on record to fund its OpenAI stake

SoftBank Group raised 11.1 billion dollars in dollar-denominated and euro-denominated bonds to fund the final stage of its OpenAI investment, in the largest high-yield sale of its kind¹. Reporting described it as the biggest junk bond sale yet² and as the world’s biggest high-yield corporate bond sale³. Another account framed it as a record Asia-Pacific high-yield bond sale⁴. In yen terms the issue was 1.76 trillion yen⁷.

The proceeds go to a commitment already made. SoftBank has committed 64.6 billion dollars to the maker of ChatGPT^2,4. Borrowing costs on the deal topped anything founder Masayoshi Son has previously paid on dollar debt⁶. The figures are the more striking because SoftBank does not carry an investment-grade rating⁵.

Why it matters to investors

This is an equity stake in a private AI company funded through the public high-yield market. Investors are bankrolling SoftBank’s AI bet at a steep price⁵, and the price paid exceeded the founder’s prior dollar borrowing costs⁶. Credit default swap spreads on SoftBank debt have already moved⁴.

The timing of the cash flows matters as much as the size. SoftBank’s investment will not be converted into cash this year⁶. That leaves a funded, illiquid position on one side of the balance sheet and dated, rated-below-investment-grade obligations on the other⁵. Son is aiming to establish SoftBank as a leading AI platform, with the OpenAI stake sitting alongside its semiconductor holdings and expanding AI infrastructure businesses⁷.

What to watch

Credit spreads are the first read. Default swap spreads on SoftBank debt have already widened⁴, and the new issue’s coupon set a high-water mark for the group’s dollar borrowing⁶.

The second is whether this route stays open. The sale is the largest of its kind on record^1,3, which by definition tests the depth of the high-yield market rather than confirming it. Son has spoken of a one-trillion-dollar AI ambition⁵, and the OpenAI commitment alone stands at 64.6 billion dollars², so the funding requirement extends well beyond this issue. Watch the ownership stake the commitment buys² and whether any of the position converts to cash on a timetable, given that it will not do so this year⁶.