Masayoshi Son, the founder, chairman, and CEO of SoftBank Group Corp., is one of the most exciting people in the high-stakes world of technology investing. He is known for making bold bets and making big comebacks. Son was born to Zainichi Korean parents in rural Japan. His story of going from a bullied teen to a billionaire mogul sounds like a Hollywood movie, with multilingual inventions, dot-com disasters, and now a key role in the AI revolution. Son isn’t just getting by; he’s doing well. As of October 2025, at age 68, he is Japan’s richest person again, with a net worth of $50.5 billion, thanks to SoftBank’s rising stock price and his never-ending quest for “artificial super intelligence.” His story shows how strong he is, and it teaches leaders how to deal with an era when AI promises to change everything from data centers to humanoid robots.
From Small and Tough Beginnings
Masayoshi Son was born on August 11, 1957, in Tosu, Saga Prefecture, a small town in Kyushu, Japan. His name at birth was Masayoshi Yasumoto. His family, ethnic Koreans who had moved to Japan during its colonial rule, faced a lot of discrimination. His grandfather worked in a mine, and his father, Son Sam-heon, made ends meet by raising pigs and chickens and running an illegal sake distillery. This business eventually made the family a little money, including the town’s first car. The family built their house illegally on land owned by the railroad, avoiding the police. Later, they moved to a new place with better schools. They used Japanese names to fit in, but young Son was still bullied and once thought about killing himself because of his heritage.
Son, who was 16 years old at the time, left high school and went to the U.S. after being inspired by Den Fujita, the founder of McDonald’s Japan. He learned English at Holy Names College, got through Serramonte High School in three weeks, and then went to the University of California, Berkeley, where he studied economics. In the middle of the late 1970s tech scene, Son’s entrepreneurial spirit came to life. He and some classmates made an electronic translator that changed Japanese into English and German. They sold it to Sharp Corporation for $1.7 million, which helped him pay for his early business ventures. He also made $1.5 million by bringing used video games from Japan and starting Unison World, a gaming company that Kyocera bought for a profit.
In 1980, Son went back to Japan with a degree from Berkeley. He took back his Korean name, which was a risky move because his family didn’t want him to, and started his first big business.
The SoftBank Saga: Building an Empire
Son started Nihon SoftBank (now SoftBank Group Corp.) in 1981 when he was 24 years old and had saved up $10,000. The company began as a software distributor and publisher of tech magazines. It was a small business in a Japan ruled by big companies like NTT, but Son’s ability to shake things up stood out. By the end of the 1980s, he was fighting NTT’s monopoly with a system that let users choose the lowest phone rates. This was a “diplomatic warfare” tactic that kept him from having to fight directly while weakening his competitors.
SoftBank grew very quickly in the 1990s. Son bought U.S. companies like Ziff-Davis Publishing and the rights to the COMDEX trade show. He then made deals, like a joint bid with Rupert Murdoch’s News Corp in 1996 to buy a stake in Asahi National Broadcasting. But his big break came in 1995 when he bought a stake in Yahoo!, which was just starting out. This put him in the orbit of Silicon Valley. He put $20 million into Alibaba in 2000, and by the time it went public in 2018, it was worth $132 billion.
SoftBank went from being a telecom disruptor (it started broadband in 2001 and bought Vodafone Japan for $17.5 billion in 2006) to a huge global investment firm. SoftBank made a nice profit when it sold its 76% stake in Sprint in 2013, which grew to 84% over time. This led to the merger with T-Mobile in 2020. He also bought Arm Holdings for $32 billion in 2016, but a deal with Nvidia fell through in 2020 because of antitrust issues. Arm’s IPO in 2023 valued it at $54 billion, and SoftBank still had most of the shares.
After the Fukushima disaster, Son’s shift to renewable energy was just as visionary. He gave $125 million to help victims, gave up his salary, and pushed for solar projects in Japan, Saudi Arabia (200GW as part of Vision 2030), and India (100GW by 2027).
The Vision Fund is SoftBank’s best and worst investment, though. With $100 billion from Saudi Arabia’s Public Investment Fund and others, it started in 2017 and focused on AI, robotics, and IoT startups. Hits like Uber, DoorDash, and Grab were great, but flops like WeWork’s near-collapse, Wirecard fraud, and Greensill’s implosion cost $27.4 billion by 2022. Vision Fund 2, which grew to $30 billion because investors were wary, did better with smaller bets, but Son admitted that the model showed a “broken” way of doing things. In 2023, when Silicon Valley Bank was having problems, a third of his shares were used as collateral for loans, which led to doomsday rumors.
Son’s personal cost was high: He once held the record for the biggest losses in history ($59 billion in the 2000 dot-com bust), a record that only Elon Musk has since broken. He admitted in 2022 that he felt “embarrassment and shame.” But Son came back, just like his nine-lives story said he would.
The AI Renaissance: Stargate and Other Shows
The AI boom has made Son a prophet again by 2025. SoftBank’s stock has gone up 60% this year, making him Japan’s richest person, ahead of Uniqlo’s Tadashi Yanai. He is now 65th on Forbes’ list of the richest people in the world, with a $50.5 billion fortune. The reason? Stargate LLC, a $500 billion AI company that was announced in January 2025 with OpenAI, Oracle, and UAE’s MGX. President Trump, Sam Altman, and Larry Ellison showed it off at the White House. It promises a network of data centers, power plants, and labs across the country to cement U.S. AI supremacy, with SoftBank paying most of the cost. “Put that name down in your books,” Son said, standing on a box so everyone could see him. As the head of Stargate, he’s very interested in “ASI,” which is AI that is 10,000 times smarter than people.
SoftBank is still on an AI buying spree: it invested $40 billion in OpenAI, bringing its value to $300 billion; it increased its stakes in Nvidia, Oracle, and TSMC; it signed a deal with Nvidia in November 2024 for Japan’s largest AI supercomputer to use Blackwell chips; and it is still looking for humanoid robotics startups. Vision Funds are interested in 125 AI companies, but Son is bridging the gap between East and West by investing in China despite tensions and working with Riyadh’s Alat on industrial robots. He called AI the next “internet moment” at a Tokyo summit with Altman in February 2025.
A Private Life Full of Differences
Son is a family man behind the tycoon facade. In 1979, he married Masami Ohno, a doctor and fellow Berkeley student. They have two daughters. His Tokyo mansion has a $85 million golf simulator that looks like courses from around the world. His $117 million Woodside, California, estate looks out over Silicon Valley. He owns the Fukuoka SoftBank Hawks baseball team and collects samurai artifacts that he keeps in his office. He also loves Burgundy wine (La Tâche is his favorite). His youngest brother, Taizo, is also a VC founder.
Son’s Zainichi roots make him a role model for Koreans living in Japan, but he thinks he would be “more conservative” if he hadn’t lived in the U.S.
What I’ve learned from taking big risks all my life
Harvard Business Review boiled down Son’s journey to eight main points: Put long-term goals ahead of short-term ones; see failures as lessons; create ecosystems instead of silos; and use “capital cannons” wisely. One CEO joked that it’s better for Son’s firepower to be aimed at the outside world than at the inside.
In October 2025, with Stargate humming and robots on the way, Masayoshi Son, who used to be the biggest loser in history, is now the last man standing in tech. What does he say? “First the information revolution, then the AI revolution.” The world will follow if history is right.
