May 23, 2026 – SoftBank added over $61 billion in market value in just two sessions. Speculation about Arm Holdings and OpenAI IPOs drove the surge. But analysts warn that risks remain for holding-company investors.
In Summary
SoftBank stock climbed over 30% across two consecutive sessions, adding $61 billion to its market cap.
NVIDIA’s record $81.6 billion Q1 revenue sparked a broad rally across AI-linked equities.
Arm Holdings, 90% owned by SoftBank, jumped over 31% across those two sessions.
SoftBank holds roughly 13% of OpenAI. An IPO filing could unlock significant value.
Analysts caution about the net asset value discount typical of holding companies.
SoftBank’s loan-to-value ratio stands at 20.6%, signaling notable financial leverage.
SoftBank Group delivered one of its most dramatic rallies in years. Shares of the Japanese investment giant surged nearly 20% on May 21, then added another 12% on May 22. The two-day run added over $61 billion to SoftBank’s market capitalization, according to CNBC. Investors treated the stock as a liquid proxy for the entire AI ecosystem.
The catalyst was unmistakable. NVIDIA reported record quarterly revenue of $81.6 billion on May 20. That result beat Wall Street estimates and reignited confidence in AI infrastructure spending. SoftBank, with deep exposure to AI through Arm Holdings and OpenAI, rose sharply in response.
The Nvidia Effect
NVIDIA’s results on May 20 acted as the spark. The chipmaker posted record revenue of $81.6 billion for Q1 fiscal 2027, up 85% year-over-year. Data center revenue alone hit $75.2 billion, a 92% annual jump. CEO Jensen Huang called the AI buildout “the largest infrastructure expansion in human history.”
Furthermore, Nvidia guided for $91 billion in revenue in the next quarter. This signal reassured investors that AI capital spending will remain robust. As a result, AI-linked holdings like SoftBank saw an immediate re-rating.
Arm Holdings: The Hidden Accelerant
SoftBank owns roughly 90% of Arm Holdings, the British chip designer. Arm’s architecture powers AI servers and data centers worldwide. NVIDIA’s AI accelerators rely on Arm-based CPU designs. Therefore, when Nvidia thrives, Arm thrives.
Arm shares rose over 15% on May 21, then added another 16% on May 22. That move directly lifted the value of SoftBank’s balance sheet. Morningstar estimates Arm now represents about 40% of SoftBank’s total asset value. No single holding matters more to SoftBank’s stock price.
“SoftBank’s share price simply reflects the moves of its stake holdings, including Arm, whose share price has been surging, and OpenAI, which may file for an IPO in the coming weeks.”
-Vey Sern Ling, Senior Equity Advisor, UBP via CNBC
The OpenAI Factor
SoftBank’s OpenAI bet has grown into one of the boldest wagers in finance. The company committed a cumulative $64.6 billion to OpenAI, acquiring approximately 13% ownership. Morningstar values that stake at around $80 billion today. That equals roughly 26% of SoftBank’s total assets.
OpenAI may file for a public market debut within weeks. Additionally, SB Energy, another SoftBank portfolio company, has already filed confidentially for a US IPO. Together, these catalysts signal significant near-term value unlocking. Investors are pricing in that prospect with enthusiasm.
Financial Performance in Context
SoftBank’s recent financials reinforce the bull case. Fiscal-year revenue rose nearly 8% to about 7.8 trillion yen. Earnings per share surged to 873 yen, more than four times the prior-year level. Its Vision Fund posted a $46 billion annual gain. OpenAI-linked gains contributed approximately $45 billion of that total.
However, much of this profit is unrealized. Valuations shift when sentiment changes. Therefore, analysts treat SoftBank less like a traditional company and more like a leveraged tech-sentiment vehicle. In good times, the upside is amplified. In downturns, losses can compound just as quickly.
Risks Investors Must Weigh
Analyst Warning
UBP’s Vey Sern Ling cautions that holding-company investors rarely receive the full value of underlying assets. Net asset value discounts are common for conglomerates like SoftBank. The stock traded at roughly a 50% discount to NAV from mid-2019 to mid-2025. Furthermore, SoftBank’s loan-to-value ratio stands at 20.6%, indicating significant leverage. A sharp reversal in Arm or OpenAI valuations could rapidly unwind recent gains.
Additionally, SoftBank sold all its Nvidia shares, valued at $5.83 billion, in October 2025. That move funded its OpenAI commitment but removed a diversifying asset. Concentration risk is therefore high. Three holdings, Arm, OpenAI, and Vision Fund residuals, now drive the bulk of value.
Moreover, the stock’s 50-year trend shows that major rallies often follow periods of underperformance. SoftBank is up over 50% year-to-date. Momentum investors have piled in. However, valuation discipline suggests caution at these levels.
What Comes Next
Three developments will shape SoftBank’s trajectory. First, an OpenAI IPO filing would act as a major value-unlocking event. Second, Arm’s next earnings report will test whether demand remains durable. Third, global AI capex trends will determine whether Nvidia’s guidance holds.
Masayoshi Son has long positioned himself as a visionary technology investor. His cumulative $64.6 billion bet on OpenAI is the defining wager of that vision. The current rally suggests markets are beginning to share that conviction. However, as with all concentrated bets, execution is everything.
For investors watching from the sidelines, SoftBank now functions as one of the most accessible ways to gain broad AI exposure. It combines semiconductor leverage via Arm with exposure to foundational models via OpenAI. That dual exposure is rare in a single publicly traded vehicle. The trade, therefore, is likely to remain crowded as long as the AI cycle holds.
