By Kosaku Narioka and Eliot Brown

SoftBank Group's appetite for OpenAI is getting costly. The investment giant's answer: more borrowing and more selling.

The Tokyo-based company run by billionaire Masayoshi Son said Thursday it took on an additional $27 billion in debt in the last three months of the year, including debt at its subsidiaries. It also sold over $3.5 billion in shares of T-Mobile, on top of the previously announced $5.8 billion it raised by selling a stake in Nvidia.

The cash helped SoftBank pay for its $22.5 billion check it wrote in December to OpenAI -- bringing the total it has injected into the company to $34.6 billion. Yet far more is needed.

SoftBank is in talks to invest as much as $30 billion more in OpenAI, The Wall Street Journal reported in late January, as the ChatGPT maker is rapidly burning cash in a bid to outcompete rivals.

The disclosures came as SoftBank reported a profit of $1.6 billion for the three months ended December, largely thanks to the growing value of its earlier investment in OpenAI.

The flood of SoftBank cash into the AI company marks the largest-ever bet by Son, a decadeslong fixture of global tech investing known for his extraordinary appetite for risk.

Investors have cheered on the concentrated bet. Shares in the company are up nearly 100% in the past year, in part because investors have turned to SoftBank as one of the few publicly traded stocks available that has a large exposure to OpenAI. SoftBank owns 11% of the company, making it the second-largest private shareholder after Microsoft.

With a series of new margin loans, it has borrowed $20 billion against its $115 billion stake in chip company Arm and $8 billion against its stake in Japanese telecom provider SoftBank Corp. Other new debt included a $3 billion loan tied to its internal hedge fund unit called Northstar.

SoftBank CFO Yoshimitsu Goto said Thursday the company's debt amounts to just 20% of the total value of SoftBank's assets -- a more conservative borrowing policy SoftBank developed after prior tech busts scared investors. The 20% figure doesn't include some borrowings, such as the margin loans on Arm shares. This is because the loans are secured by the shares, meaning SoftBank itself isn't on the hook to repay them, according to the company.

Goto pointed to a number of other options for raising additional cash, including the possibility of more bonds -- or selling stakes in other companies it owns. Through its Vision Fund unit, a large startup investment fund, it owns over $23 billion of publicly traded company shares, including in companies such as Korean e-commerce site Coupang and Asian ride-hailing company Grab.

SoftBank's stock got a boost this week after Japanese Prime Minister Sanae Takaichi's election victory on Sunday fueled expectations that she will increase strategic investment in key industries such as AI and semiconductors.

Past big wagers have cost Son when they have failed -- he nearly lost his entire fortune in the dot-com bust, while his investment in WeWork has left a long-lasting black eye -- and led to tens of billions of dollars in profits when successful, as was the case with an early investment in Alibaba and a bet on Vodafone's Japanese unit.

Write to Kosaku Narioka at kosaku.narioka@wsj.com and Eliot Brown at Eliot.Brown@wsj.com

(END) Dow Jones Newswires

February 12, 2026 10:40 ET (15:40 GMT)

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