SoftBank founder Masayoshi Son loses $2.6 billion in two days. Here's why

Masayoshi Son is up about $2.7 billion from the $11.3 billion at the starting of the year, as per Bloomberg Billionaires Index.

SoftBank founder Masayoshi Son's fortune fell by $2.6 billion owing to a two-day wipeout in shares of the company SoftBank Group Corp owing to Bank of Japan’s earlier-than-expected interest-rate hike. The company's shares were down 8% today and the stock fell 14% in over two days. Masayoshi Son is up about $2.7 billion from the $11.3 billion at the starting of the year, as per Bloomberg Billionaires Index.

Masayoshi Son, CEO of SoftBank, arrives for the annual Allen and Co. Sun Valley Media and Technology Conference at the Sun Valley Resort in Sun Valley, Idaho.(Reuters)

SoftBank, among the world’s biggest tech investors, had been up 46% through the end of July. The company owns most of chipmaker Arm Holdings Plc whose shares soared this year flanked by expectations for artificial intelligence. But Arm Holdings' shares also fell 16% after an existing annual sales forecast.

Japanese shares dropped the most since 2016 as the fallout from tighter monetary policy roiled the market. Japan’s currency climbed to a four-month high following hawkish signals from the BOJ earlier in the week.

Masayoshi Son, 66, is SoftBank’s largest shareholder in the nearly $78 billion giant. Most of his stake is pledged as collateral against loans with various financial institutions.