Record Profit, Slumping Stock: SoftBank’s $64.6 Billion OpenAI Wager Rattles Investors

SoftBank posts record ¥5 trillion profit driven by OpenAI valuation, but market sell-off and S&P negative outlook signal concern over concentration and debt funding.

SoftBank Group delivered a landmark net profit of ¥5.002 trillion (roughly $32 billion) for the fiscal year ended March 2026 — the highest ever recorded by a Japanese corporation. Yet the market greeted the milestone with a near 4% sell-off on Thursday, pushing the stock to ¥5,725 and leaving it trailing the broader Tokyo index. The disconnect between headline earnings and investor sentiment stems from a single, massive bet: OpenAI.

The bulk of SoftBank’s profit — roughly 92% of its investment gains — exists only on paper, driven by a ¥6.73 trillion upward revaluation of its stake in the ChatGPT developer. SoftBank now values that holding at nearly $80 billion, a book profit of $45 billion. But the real story lies in the planned escalation: the group intends to sink a total of $64.6 billion into OpenAI by the end of the calendar year, up from $34.6 billion already committed. That would lift its ownership to around 13%.

To fund the ambitions, SoftBank is leaning heavily on debt. A recently secured bridge financing of $17.5 billion is on the books, and the group has already sold its remaining Nvidia shares. Further loans are backed by its prized Arm stake and the domestic telecom unit. But the credit environment is turning chillier: S&P Global has revised its outlook on SoftBank to negative, flagging deteriorating liquidity and portfolio quality. Banks have also grown reluctant to accept OpenAI shares as collateral, forcing SoftBank to downsize a planned $10 billion margin loan.

The concentration risk does not end with OpenAI. SoftBank’s Vision Fund reported a $1.4 billion valuation loss on Coupang in the fourth quarter after a data breach hammered the e-commerce company’s stock. Meanwhile, a bid to acquire chip startup Cerebras Systems for roughly $34 billion collapsed when the company turned down the offer just ahead of its planned initial public offering. Cerebras, known for its wafer-scale chips that compete with Nvidia in training large language models, would have given SoftBank a direct rival to the GPU giant. Instead, the group is now counting on its own chip designer, Arm.

Arm is preparing to launch dedicated CPUs for AI workloads, and SoftBank recently snapped up server-processor specialist Ampere Computing for $6.5 billion to deepen its hardware arsenal. The strategy is to become a full-stack AI infrastructure provider, not merely a financial backer of software.

That push extends into physical infrastructure. SoftBank’s domestic telecom arm, which posted a solid 8% revenue rise to ¥7.04 trillion, is building a massive battery business to power AI data centers. The group is also pursuing two significant acquisitions: ABB’s robotics division for roughly $5.4 billion and infrastructure firm DigitalBridge for $4 billion. These moves complement a $100 billion investment pledge for AI data centers in France, announced after a meeting with President Emmanuel Macron, with further US projects in the pipeline.

Despite the record profit and ambitious spending, the Japanese conglomerate’s balance sheet shows some resilience. Net asset value stood at ¥40.1 trillion, the loan-to-value ratio improved to 17%, and the telecom business generated over ¥600 billion in free cash flow. Yet the market’s skepticism reflects a straightforward calculus: SoftBank’s entire AI dream now hinges on the willingness of lenders to keep advancing billions for a single, highly concentrated bet. The next test comes with the planned US initial public offering of robotics subsidiary Roze, which could provide fresh capital — or reveal how deep the enthusiasm for SoftBank’s strategy truly runs.