SoftBank CEO Masayoshi Son has made an “all in” bet on OpenAI, ramping ‌up ⁠investment in artificial intelligence. Just months ago, SoftBank Group, owned by Japan’s second-richest man Masayoshi Son, reportedly raced to finalise a $22.5 billion funding commitment to Sam Altman’s OpenAI by year-end. According to a report in Reuters, the company used a complex array of cash-raising methods that include liquidating major stakes and potentially tapping billions in margin loans. The massive capital injection was called a defining “all-in” move by SoftBank CEO Son. On the way, the Japanese giant executed a series of aggressive divestments to build its war chest, including selling its entire $5.8 billion stake in the world’s most-valuable company Nvidia and offloading $4.8 billion of its holding in America’s biggest telecom service provider T-Mobile. And with this, the Japanese company held a stake of about 11% in OpenAI at the end of last year.However, as a report in Financial Times says, Masayoshi Son’s big bet on AI and Sam Altman seems to be hurting the company. On Monday, March 9, SoftBank shares dropped as much as 12.5%, reaching their lowest level since August 2025 as markets weighed the implications of the group’s expanding AI commitments. The pressure on the stock reportedly came after Oracle and OpenAI are said to have scrapped plans to expand a flagship artificial intelligence data center in Texas that had been part of the broader Stargate initiative. With this, SoftBank Group Corp’s credit default swaps (CDS) widened to an 11-month high and remained the widest among Japanese companies as its heavy investment in OpenAI weighed on its credit profile.In the past few months, the Japanese giant’s shares have nearly halved as questions have grown over the scale of its involvement with OpenAI. Earlier this month, S&P Global Ratings revised SoftBank’s outlook to negative on March 3, citing the company’s additional investment in OpenAI. The rating agency slapped a negative outlook on its already-junk rating for the Japanese group. Separately, S&P said that OpenAI is among SoftBank’s investments with the weakest credit quality. It added that many of its AI-related investments are exposed to significant innovation risk and intense competition, and that the creditworthiness of its investment portfolio may deteriorate.What reportedly makes it more troublesome is that SoftBank is seeking bridge loans to cover its OpenAI investment until the company can generate funds from selling some of its other holdings. It has liquid assets including $80bn worth of chip designer Arm and sold its Nvidia stake last year to fund an earlier OpenAI investment. And earlier this year, Softbank also pushed ahead with a $1 billion float in New York of PayPay, its Japanese digital payments platform.

How Softbank is not alone

Incidentally, Softbank is not the only company not doing well after its big bet on OpenAI. Two other tech giants who too have seen huge dents in their market value are Oracle and CoreWeave. The two American companies are also down more than two-fifths. In September 2025, Oracle revealed that its remaining performance obligations (RPO) soared by triple digits to reach a $455 billion backlog, powered by cloud demand from OpenAI. The news sent Oracle stock soaring more than 30% in a single day. But shares have tumbled since. The big September rally has reportedly been halted by worries about the amount it will cost Oracle to build cloud data centers and how much its cloud backlog relies on OpenAI.