SoftBank has officially wired the final $10 BILLION into OpenAI.
And the way Masayoshi Son financed this AI bet is almost as interesting as the size of the bet itself.
On October 1, SoftBank confirmed that it completed the third and final $10 billion tranche of its latest OpenAI investment.
That brings SoftBank’s cumulative investment in OpenAI to $64.6 billion — for approximately 13% ownership.
But look at the financing journey.
Back in October 2025, SoftBank sold its entire Nvidia stake — 32.1 million shares worth about $5.8 billion — as it redirected capital toward its rapidly expanding AI investments, including OpenAI. SoftBank said the sale was not a negative view on Nvidia; it was a portfolio-reallocation decision.
Then came the borrowing.
To finance this latest OpenAI commitment, SoftBank raised $11.1 billion in dollar-and euro-denominated senior notes in September.
It was the largest high-yield corporate bond issuance ever recorded, according to Reuters.
The bonds carry yields ranging from 7.125% to 9.75%.
And on October 1, SoftBank confirmed that the proceeds from those notes funded the final $10 billion OpenAI tranche.
So the sequence is striking:
Sell Nvidia → recycle capital → borrow billions → invest in OpenAI → reach $64.6B cumulative exposure.
And this isn’t SoftBank simply writing a $64.6 billion check from cash.
It is a much more leveraged capital-allocation strategy involving asset sales, financing facilities, bonds and its broader portfolio.
SoftBank had originally arranged a $40 billion bridge facility for its OpenAI investments. After completing the final tranche, it canceled the remaining $10 billion of undrawn capacity and says all borrowings under that facility have now been repaid.
The scale is extraordinary.
$64.6 billion invested. ~13% of OpenAI. $30 billion committed in the latest three-tranche round alone. $11.1 billion raised in the world’s largest high-yield corporate bond deal to help fund the final tranche.
This is no longer just a venture-capital bet on an AI company.
It is a massive capital-markets bet on the future of AI.
And SoftBank isn’t the only one making these kinds of moves.
AI is increasingly being financed not only with venture and equity capital, but with bonds, loans, infrastructure financing and increasingly sophisticated forms of leverage.
The big question isn’t simply how much money is flowing into AI.
It’s how much of the AI boom is now being financed by debt — and what happens to that financial architecture if the expected growth takes longer than investors anticipate?
That may be one of the most important stories underneath the AI boom.
#softbank #MasayoshiSon #openai #ArtificialIntelligence #NVIDIA #capitalmarkets
SoftBank Group Corp. today announced that, on October 1, 2026 (Japan time), it executed the third and final tranche of the follow-on investment in OpenAI Group PBC via SoftBank Vision Fund 2, in the amount of USD 10.0 billion announced in “Follow-on Investments in OpenAI” dated February 27, 2026.