SoftBank’s ¥5 Trillion Profit Masks a Double Blow: Cerebras Rejection and OpenAI Dependency

SoftBank posts ¥5 trillion annual profit, but shares fall 4.6% as investors worry over OpenAI concentration, a failed Cerebras acquisition, and rising debt costs.

Japan’s SoftBank Group posted the fattest annual profit in its history on May 13, yet the market response was anything but celebratory. Shares slid 4.61% on Thursday to close at ¥5,735, after opening at ¥6,100 and touching a low of ¥5,714. The sell-off followed a blistering run — the stock had surged 13.43% in the prior week and 58.43% over the past month — but the euphoria evaporated as investors digested two uncomfortable realities: a failed acquisition bid for chip startup Cerebras Systems and the precarious concentration of earnings in a single unlisted AI bet.

The headline numbers were spectacular. Net profit for fiscal 2025 hit ¥5 trillion ($32 billion), up from ¥1.15 trillion a year earlier, while revenue crossed the ¥7 trillion mark for the first time. Almost all of that improvement came from OpenAI. SoftBank booked valuation gains of ¥6.73 trillion on its stake in the AI pioneer, representing 92% of the group’s total investment income. At the end of March, the OpenAI holding was worth $79.6 billion, delivering a cumulative gain of $45 billion on the initial outlay.

Strip out OpenAI, and the picture darkens. The Vision Fund’s stakes in Coupang, DiDi Global and Klarna all lost money in the fourth quarter. SoftBank wrote down $1.4 billion on the South Korean e-commerce giant Coupang alone. Meanwhile, financing costs jumped to ¥229.4 billion in the final quarter, up from ¥148.9 billion a year earlier, as heavy borrowing to fund AI investments took its toll. S&P Global Ratings cut its outlook on SoftBank from stable to negative in March, flagging the one-sided concentration and dwindling financial flexibility.

The failed approach for Cerebras Systems underscores the challenge. SoftBank and its majority-owned chip-design subsidiary Arm Holdings made a move to acquire the AI computing company shortly before its planned initial public offering, according to sources. Cerebras rebuffed the offer, preferring to press ahead with a listing that now targets a valuation of around $48.8 billion. The price range was recently raised to $150–$160 per share from an initial $115–$125, reflecting red-hot demand for AI hardware. Cerebras differentiates itself from Nvidia with a wafer-scale engine chip that uses an entire silicon wafer as a single processing unit.

The setback does not mean SoftBank is retreating from chips. It closed the $6.5 billion acquisition of Ampere Computing late last year, and Arm is developing its own chip lineup — a significant departure from its traditional licensing model. SoftBank’s domestic mobile unit is also pivoting toward AI infrastructure, with plans to offer compute services and even manufacture large battery cells. The goal is greater control over the key layers of the AI value chain.

The financing side, however, remains the sore spot. SoftBank had to scale back plans for a margin loan secured against its OpenAI stake, from an original target of $10 billion to around $6 billion, after lenders showed caution. A $40 billion bridge loan arranged in March still supports the OpenAI investment and general corporate purposes, but $17.5 billion of that facility remains outstanding. On a more positive note, the stake in Arm jumped 38% in the March quarter, and CFO Yoshimitsu Goto pointed to a liquidity position of ¥3.5 trillion — enough to cover more than two years of bond redemptions.

SoftBank’s total cumulative investment in OpenAI reached $34.6 billion in the fourth quarter, representing roughly an 11% stake. An additional $30 billion in future funding rounds was agreed in February, which would push total exposure to around $64.6 billion and the ownership share to about 13%. The company declined to provide profit guidance for the current fiscal year, citing exceptional uncertainty. For a group that derives 92% of its earnings from a single unlisted AI firm, that reluctance is entirely understandable. The market’s judgment on Thursday suggests it shares the skepticism.