The US bank is believed to have invested US$450 million in Facebook, while DST has provided a further US$50 million.
Facebook, which has more than 550 million users worldwide, refused to comment on the deal. It was valued at US$10 billion in May 2009, after DST paid US$200 million for a 2 per cent equity stake in the company.
The valuation has triggered speculation that Facebook could be considering an initial public offering.
Facebook's chief executive Mark Zuckerberg, who co-founded the site in 2004, was named Time Magazine's Person of the Year in 2010. He is estimated to have a fortune of US$14 billion.
This article was first published on mediaweek.co.uk.