Tokyo, 24 September 2026 — EBM Newsdesk Analysis — By Katie Winearls
SoftBank has raised $11.1bn in what is now the largest high-yield corporate bond sale in history, surpassing French telecoms firm Numericable’s $10.9bn 2014 issuance. The deal splits into $10bn of dollar-denominated notes across three maturities and €1bn in euro notes, with proceeds earmarked for the next tranche of SoftBank’s OpenAI investment, due to close next month. It’s also the largest non-financial corporate bond deal ever completed in Asia Pacific and Japan, and ranks among the twenty largest corporate bond transactions globally this year.
What “Steep Price” Actually Means
The record size masks a genuinely uncomfortable detail for SoftBank: the cost of borrowing it. The yield on SoftBank’s dollar bond due 2031 has climbed to 8.2%, up from a low of 6.7% in January, and the cost of insuring SoftBank’s debt against default has reached its highest level in three years. SoftBank carries a BB+ rating from both S&P and Fitch — the top tier of speculative grade, but still junk. For comparison, 2026’s biggest investment-grade bond issuers, Alphabet and Amazon, carry AA+ and AA ratings respectively — both higher than Japan’s own sovereign rating. That gap is the entire story in one comparison: SoftBank is borrowing at junk-bond rates to fund a bet the market doesn’t yet treat as investment-grade collateral, however large the headline number gets.
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SubscribeThis Is the Third Debt Instrument This Year
The bond sale isn’t SoftBank’s only recent financing move. It follows an $11.87bn two-year syndicated loan arranged roughly a week earlier with around 20 banks, on top of a separate $10bn margin loan collateralised directly against SoftBank’s OpenAI shares, and a raised $25bn limit on a margin loan backed by Arm Holdings, up from $5bn previously. EBM has tracked how concentrated SoftBank’s OpenAI exposure has already become: S&P calculates OpenAI now represents roughly 30% of SoftBank’s investment assets, on par with its Arm stake, and downgraded SoftBank’s credit outlook to negative on exactly this concentration risk. SoftBank’s total cumulative OpenAI investment is set to reach approximately $64.6bn once the current tranche completes, for a roughly 13% stake — stacking three separate debt instruments on top of an already heavily concentrated equity bet.
Why the Timing Makes This Riskier
Two developments have specifically unsettled the market SoftBank is borrowing into. AI industry leaders have publicly called for slowing the pace of AI investment, and OpenAI chief executive Sam Altman has confirmed the company will not go public this year — pushing back the one clear mechanism SoftBank has to convert its paper gains into actual liquidity it could use to pay down this new debt. EBM covered OpenAI’s own financial position when it filed confidentially for what would be the largest IPO in history: $2bn in monthly revenue, losing $1.22 for every dollar earned, with profitability not expected before 2029. CreditSights analyst Chapman has said a ratings upgrade is plausible in the intermediate term if OpenAI’s eventual IPO lands “timely and successful” — which is precisely the condition currently sitting furthest away.
The Market’s Actual Verdict
SoftBank shares rose 7% on news of the completed bond sale, which reads less as enthusiasm for more debt and more as relief that the company could still raise this scale of capital at all, at a moment its stock has already shed roughly 34% since its June all-time high. Investors appear to be pricing certainty over cost: a completed $11.1bn raise, however expensive, removes near-term funding uncertainty that had been weighing on the shares more heavily than the yield itself.
My Read: SoftBank isn’t struggling to raise money — a record-breaking, oversubscribed bond sale proves the opposite. What the pricing actually reveals is that credit markets have started treating Masayoshi Son’s OpenAI conviction as a genuine risk factor rather than a foregone conclusion, something no amount of headline-grabbing deal size can hide. Every dollar of that 8.2% yield is the market’s own honest assessment of how much uncertainty still sits between SoftBank and the payoff it’s betting everything on. The bond sale bought SoftBank time and liquidity. It didn’t buy conviction — that’s still entirely resting on whether OpenAI’s IPO eventually happens, and on what terms, whenever “eventually” turns out to be.
