SoftBank Shares Rise to Record High, Making Masayoshi Son Asia's Richest Person

SoftBank Group shares reached a record high on Monday, pushing the company's market capitalization to $298 billion and making it Japan's most valuable company by that measure. The gain lifted Masayoshi Son's net worth to $97 billion, surpassing Mukesh Ambani's $90 billion fortune and placing Son at the top of Forbes' Real-Time Billionaires List for Asia.

The 68-year-old executive holds the bulk of his wealth through his stake in SoftBank. Shares of the investment firm have risen more than 80 percent this year, driven by gains in its portfolio companies.

Son told CNBC in a Monday interview that the AI opportunity could be 50 times larger than the dot-com era. The previous day he announced plans to invest as much as €75 billion in AI infrastructure, including data centers, in France. Arm Holdings, in which SoftBank holds nearly a 90 percent stake, reported that its own shares have climbed more than 250 percent this year.

The British chip designer said Tuesday it may reach its $15 billion annual chip sales target ahead of its earlier schedule.

SoftBank has invested more than $30 billion in OpenAI and committed to at least another $20 billion by October. OpenAI was valued at $852 billion after a March funding round that included Amazon, Nvidia, and SoftBank. Deutsche Bank analyst Peter Milliken noted in a Tuesday research note that OpenAI faces competition from Anthropic, which reached a $965 billion valuation after a May funding round.

He also pointed to growing adoption of open-source AI models as a potential constraint on OpenAI's growth. Morningstar data showed SoftBank reduced its leverage ratio to 17 percent in the fiscal fourth quarter, remaining below the company's self-imposed 25 percent limit.