Softbank diluted to 34.2% after RenRen's initial public offering, having originally invested $100m in April 2008, according to data provider Zero2IPO. By December last year, Softbank had invested $315m to give a six times return on the book value of its holding at $14 per share, Zero2IPO added.

Japan-based internet group Softbank has made a paper profit of a reported six times from its one-third holding in RenRen, a China-based social networking service, that raised up to $584.1m in its New York flotation.

RenRen offered 53.1 million American depository shares (ADS) at $14 each, the top end of its revised range.

Its opening price of $19.50, was 39.3% up from issue price, and RenRen’s first day closing was $18.01 per share giving a market capitalization of more…