资金来源是第一个压力点。Masayoshi Son 去年完成 300 亿美元投资时，靠出售 Nvidia Corp. 全部 58 亿美元持股、出售 T-Mobile US Inc. 股票 92 亿美元、发债，并扩大以 Arm Holdings Plc. 作担保的融资（含可延后付息的美元混合证券，但成本偏高）。如今要再凑 300 亿美元更难，因为最具流动性的资产已大幅处理；且 Arm 股价较 10 月高点下跌 35%，使得卖股或加码融资的空间缩小。
融资环境与估值共识是第二个压力点。SoftBank 在日本零售日圆公司债市场占比约 42%（截至去年 5 月），而日本利率上行提高其利息负担；美元债市场亦因 AI 超大规模资本开支而转趋谨慎，SoftBank 去年 10 月发行的 8.25% 混合证券现约以面值每 1 美元 0.93 美元交易。同时 Altman 寻求中东资金，以约 7,500 亿至 8,300 亿美元估值完成约 500 亿美元一轮募资，较去年 10 月至少高 50%；SoftBank 之所以乐见更高估值，与其 2025 年 3 月以 2,600 亿美元 pre-money 进场、后续在 5,000 亿美元估值下按市价认列，以及最近一季因 OpenAI 股份录得 128 亿美元公允价值收益、创三年最佳表现直接相关。但其他投资人未必跟进，且 Son 过往在 WeWork 与 Oyo Hotels 等案例中曾在连续高跳估值后承受巨额减记；在 AI 资本密集竞争下，Alphabet Inc. 仍握有近 1,000 亿美元现金，而 Anthropic 也可能更早转盈，令 OpenAI 的估值与投入回报更难自证。
The column dated January 29, 2026 at 03:00 GMT+8 (UTC+8) criticizes Sam Altman and Masayoshi Son for overreaching: SoftBank Group Corp. is reported to be in talks to invest up to $30 billion more in OpenAI Inc., while OpenAI is seeking to raise as much as $100 billion at a valuation as high as $830 billion. If done, the deal would bind the two companies’ fortunes even tighter; SoftBank is already a major OpenAI shareholder, and its existing 11% stake is said to represent about 26% of SoftBank’s net asset value.
Funding is the first constraint. Masayoshi Son funded last year’s $30 billion OpenAI investment by selling his entire $5.8 billion stake in Nvidia Corp., selling $9.2 billion of T-Mobile US Inc. stock, issuing bonds, and expanding financing backed by Arm Holdings Plc. (including dollar-denominated hybrids that can defer coupons but proved costly). Raising another $30 billion is harder because the most liquid assets have already been sold down, and Arm shares are down 35% from their October high, limiting both share sales and additional margin borrowing.
Financing conditions and valuation consensus are the second constraint. SoftBank accounts for about 42% of Japan’s retail yen bond market (as of last May), and rising Japanese rates increase its interest burden; in dollar credit, markets are turning wary of an AI-driven borrowing binge, and SoftBank’s 8.25% hybrid issued last October trades around $0.93 per $1 of face value. At the same time, Altman has sought Middle East funding for a roughly $50 billion round at about a $750–$830 billion valuation, at least 50% higher than last October; SoftBank benefits from higher marks, given its March 2025 entry at a $260 billion pre-money valuation, later mark-to-market at a $500 billion employee-share-sale valuation, and a recent $12.8 billion fair-value gain that helped produce its best quarterly result in three years. Other investors may not follow, and Son’s history of repeated, sharply higher rounds that end in write-downs (e.g., WeWork and Oyo Hotels), plus capital-intensive competition where Alphabet Inc. holds nearly $100 billion of cash and Anthropic may reach profitability earlier, makes the proposed repeat $30 billion bet more exposed to funding and valuation optimism.