- Uniqlo founder Tadashi Yanai is stepping down from SoftBank's board after 18 years.
- Yanai is Japan's richest person, and reportedly acted as a bulwark against CEO Masayoshi Son, who has a penchant for risky investments.
- SoftBank has endured a year where Son's investments in startups like WeWork have resulted in serious losses.
- A SoftBank spokeswoman told Bloomberg that Yanai is leaving to focus on his own business.
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SoftBank is losing one of its most influential board members.
The company announced Friday that non-executive director Tadashi Yanai will step down from the board on December 31.
Yanai is the founder and president of Fast Retailing, parent company to clothing chain Uniqlo. His net worth is estimated to be around $31.4 billion according to Bloomberg's Billionaires Index, making him the richest person in Japan.
Yanai has spent 18 years on SoftBank's board, and had a reputation for being one of the few people with as much clout as CEO Masayoshi Son. He has reportedly taken issue with some of Son's riskier acquisitions in the past.
The two have previously joked about their relationship. At a SoftBank presentation in June Yanai said: "I always oppose Son in everything he does ... Dreams are all good, but nothing beats realistic management. Let's keep our feet firmly on the ground," according to a report from Bloomberg.
Sources close to the company told the Financial Times that Son was eager to keep Yanai on the board.
SoftBank has had a turbulent year. The company reported a $6.5 billion loss in November, its first quarterly loss in 14 years. The loss was largely triggered by investments in Uber and WeWork, which SoftBank had to bail out for $9.5 billion after its failed IPO.
A SoftBank spokeswoman told Bloomberg that Yanai was stepping down to focus more on his own business.