Forbes put Masayoshi Son’s net worth at $64 billion in July 2026, ranking Son 30th in the world. That number is an estimate, not a disclosure, and it has swung by more than $30 billion inside a single quarter.
Key facts about Masayoshi Son’s net worth
| Detail | What is known |
|---|---|
| Reported net worth | $64 billion (Forbes, 19 July 2026); peaked near $100.7 billion in June 2026 |
| Full name | Masayoshi Son, born Masayoshi Yasumoto |
| Born | 11 August 1957, Tosu, Saga Prefecture, Japan (age 68) |
| Primary income source | Roughly a third of SoftBank Group, founded 1981 |
| Education | Economics, University of California, Berkeley, 1980 |
| Marital status | Married to Masami Ohno since 1979; two daughters |
Why the Masayoshi Son net worth figure moved $36 billion in six weeks
June 2026 was the clearest demonstration of how thin these estimates are. On 3 June, Son passed Mukesh Ambani to become Asia’s richest person on an AI-driven SoftBank rally.
The title lasted a day. Forbes recorded a $13 billion drop on 4 June, and by 11 June the figure had fallen from about $97 billion to $75.3 billion after SoftBank stock dropped more than 14 percent to ¥6,374 in a single session.
The trigger was reported by Bloomberg: SoftBank’s attempt to raise $6 billion in margin loans against its OpenAI holding had stalled, because lenders were reluctant to accept collateral in a company with no public market price.
Masayoshi Son net worth, 2000 to 2026
Estimated fortune at selected dates, in billions of US dollars.
Sources: Forbes real-time and list data, Bloomberg Billionaires Index, Wikipedia. All figures are third-party estimates derived from SoftBank’s share price, not audited disclosures.
What Masayoshi Son actually owns
Nearly all of the estimate traces back to one holding. Son is SoftBank’s founder and largest shareholder, with a stake reported at 34 percent by The Japan Times in December 2022 and roughly a third since.
SoftBank posted a record net profit of ¥5 trillion, about $31 billion, for the year ended 31 March 2026. The company completed a $40 billion investment in OpenAI on 30 December 2025, including a final $22.5 billion tranche, for a stake reported near 10 percent.
The older wins still anchor the story. A roughly $20 million bet on Alibaba in 1999 turned into one of the highest-returning venture cheques ever written, and the 2016 purchase of the British chip designer Arm for £24.3 billion now underpins a large share of SoftBank’s group balance sheet.
Why the borrowing matters to any Masayoshi Son net worth estimate
Son borrows against SoftBank stock, which means the headline figure is gross rather than net. As of December 2025, 154.2 million shares, about 31 percent of the personal holding, sat pledged to lenders.
That is down from close to 39 percent in March 2020, after Son cut pledges by 19.4 million shares worth $2.1 billion. No public filing nets those loans out of the published wealth rankings.
Share of Son’s SoftBank stock pledged to lenders
Percentage of the personal holding posted as loan collateral.
Source: Bloomberg, 12 December 2025. Pledge levels move with the share price and are reported irregularly, so treat both figures as point-in-time snapshots.
The $78 billion Masayoshi Son lost once before
Anyone reading a 2026 valuation should know what happened in 2000. Son’s fortune peaked at roughly $78 billion that February, briefly making Son the richest person alive on paper.
By October 2002 the estimate was $1.1 billion, after SoftBank’s market value fell about 98 percent from its peak. Nothing about the balance sheet changed that fast; the share price did.
The Vision Fund repeated a smaller version of it, posting a record $27.4 billion loss in the 2022 financial year on positions including WeWork. Son personally owed SoftBank $5.1 billion on side-deal arrangements as of February 2023, one reason governance analysts treat Son’s reported wealth and SoftBank’s reported wealth as tangled rather than separate.
Who is Masayoshi Son, and where does Son live now
Son was born in a squatter settlement in Tosu, Saga Prefecture, to Zainichi Korean parents, and used the Japanese surname Yasumoto in childhood before adopting Son professionally.
At 16 Son moved to California, cleared the Serramonte High School requirements in about three weeks, and finished an economics degree at Berkeley in 1980. Son met Masami Ohno there, and the couple married in 1979.
Son lives in Tokyo and chairs the Stargate AI infrastructure venture announced in 2025. The best-documented piece of the Masayoshi Son house question is American: a Woodside, California estate bought in 2012 for $117.5 million, then the highest price paid for a single-family home in the United States. Exact residential addresses are not publicly disclosed.
Discussion of the Masayoshi Son net worth on Reddit tends to circle the same point this article makes, which is that a fortune sitting inside one volatile listed stock, partly pledged as collateral, is not the same thing as $64 billion in cash.
Frequently asked questions
What is Masayoshi Son’s net worth in 2026?
Forbes listed Masayoshi Son at $64 billion on 19 July 2026. The same publisher’s Japan’s 50 Richest ranking, priced weeks earlier, put Son at $80 billion, which is a useful reminder that list figures are frozen at a pricing date.
How much was Masayoshi Son worth in 2025?
Bloomberg estimated Son’s fortune at $33.3 billion in mid-August 2025, second in Japan behind Tadashi Yanai, after an $11 billion gain in the first two weeks of that month.
What does Reddit say about Masayoshi Son’s net worth?
Reddit investing threads generally treat the Masayoshi Son net worth figure as a proxy for SoftBank’s share price rather than a measure of liquid wealth, and the pledged-share disclosures come up often. Those threads are opinion, not sourcing, and no Reddit estimate is verified.
Is Masayoshi Son married, and does Son have children?
Son married Masami Ohno in 1979 after the two met at Berkeley, and Forbes lists two children. Ohno keeps a low public profile and no separate net worth figure exists for the family beyond Son’s own.
Where did Masayoshi Son go to college?
Son studied English at Holy Names College in Oakland before transferring to the University of California, Berkeley, graduating in economics in 1980.
