Record Yields on a Landmark Deal
The smallest slice, $1 billion of 3.5-year notes, carries guidance of 8.75% to 8.875%. The two larger pieces, $4.5 billion each in 5.5-year and 7.5-year paper, are talked higher still, at 9.375% to 9.5% and 9.75% to 9.875%. Add the €1 billion euro portion, split across 4-year and 6-year notes, and the whole package tops $11 billion, with SoftBank aiming to lock in pricing September 24 and settle five days later. Fitch put a BB+ on the notes, the same mark S&P already has on SoftBank, sitting one rung below investment grade. None of that seems to have put investors off. Orders ran past $20 billion, close to double what SoftBank is actually selling, despite coupons that sit well clear of what the company was paying to borrow at the start of the year.
The OpenAI Commitment Behind the Raise
Proceeds will go primarily toward the $10 billion third tranche of SoftBank's follow-on investment in OpenAI, due by October 1, 2026. That payment takes SoftBank's cumulative stake in OpenAI to $64.6 billion, around 13% of the company, almost all of it debt-funded rather than paid for with equity or asset sales. Nobody else has put this much borrowed money behind a single private company. SoftBank arranged a $40 billion bridge facility in March 2026, drew $30 billion against it, and has since prepaid $25.9 billion of that amount, leaving roughly $4.1 billion still outstanding. It also lined up nearly $21 billion in fresh borrowing capacity in mid-September 2026. It has sold almost $15 billion of bonds across currencies so far in 2026, more than any other junk-rated company in the world.
Rising Borrowing Costs, Growing Caution
The pricing reflects a market that has become notably less forgiving. The yield on SoftBank’s dollar bond maturing in 2031 climbed to 8.2% earlier this month, up from as low as 6.7% in January 2026, as credit spreads widened alongside rising Treasury yields, and the cost of insuring SoftBank’s debt against default has risen to its highest level in three years. Two developments have added to that caution. Some leaders across the AI industry have argued publicly for slowing the pace of AI investment on safety grounds, and OpenAI chief executive Sam Altman has said a public listing will not happen in 2026. The latter matters directly to bondholders: it removes, for now, the clearest path by which SoftBank’s OpenAI stake could be converted into cash or used to deliver.
What Remains Unresolved
SoftBank has now borrowed heavily, at its highest cost in years, to back a company that isn't public and that it can't easily sell out of. A higher OpenAI valuation would make that leverage pay off handsomely. A setback would leave SoftBank holding expensive, junk-rated debt against one illiquid position. With that exit pushed off indefinitely, there's no clear date by which anyone will know which of those two outcomes SoftBank is actually facing. If the AI boom keeps funding itself this way, the question isn't whether SoftBank can service the debt. It's what happens to everyone holding it if OpenAI's valuation ever needs to be tested in public.