Will masayoshi son become japans richest person? How much is son a billionaire worth? If you started with $10,000 and invested an additional $500 each month at a 40. 58% cagr, it would take you 37. 44 years to reach masayoshi son s net worth of $49. 1b. Who is masayoshi son? Son ’ s net worth jumped 248% this year to $55. 1 billion on wednesday, about $23 million larger than yanai’s, the chairman and biggest shareholder of uniqlo’s parent company fast retailing co. How much is mr sons net worth in 2025? · the softbank (sobky) founder has overtaken uniqlos tadashi yanai to become japans richest man, as his net worth surged 248% this year to $55. 1 billion, according to bloomberg. Find out his latest moves in ai, such as sb openai japan and a possible investment in openai. · how long would it take you to become as rich as masayoshi son ? Stakes in publicly traded companies are valued using the shares most recent closing price. · mr son ’s net worth soared 248 per cent in 2025 to us$55. 1 billion (s$71 billion) on oct 29, about us$23 million larger than mr yanai’s, the chairman and biggest shareholder of uniqlo’s parent. · masayoshi son is #2 on forbes 2025 japans 50 richest list. · learn how softbank group chairman and ceo masayoshi son amassed his $17 billion fortune from his stake in the company and his stakes in various tech startups.