Masayoshi Son, founder of SoftBank Group, has become Japan’s richest person with an estimated net worth of US$55.1 billion, according to the Bloomberg Billionaires Index.

Son overtook Tadashi Yanai, chairman and largest shareholder of Uniqlo’s parent company Fast Retailing, who held the top spot for over three years.

SoftBank, a Tokyo-listed conglomerate with investments in tech and telecommunications, has seen its share price rise in 2025, as the firm positions itself in AI-related businesses.

Son holds about one-third of SoftBank’s shares and has outlined plans for major investments, including a proposed US$30 billion in OpenAI and a US$500 billion AI infrastructure project in the US.

The gains in Son’s fortune this year have been driven by SoftBank’s stakes in companies such as Arm Holdings, Nvidia, Intel, and TSMC.

🔗 Source: Bloomberg

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