Tyler and Cameron Winklevoss, best known for their epic legal battle with Mark Zuckerberg over ownership rights to Facebook, have reportedly invested $1 million (£620,000) in a new social network aimed at the financial community, called SumZero.

Founded by fellow Harvard alumni Divya Narendra and Aalap Mahadevia in 2008, SumZero has about 7,500 members. The network enables users to get advice from other investors, and spread the word about investments they have made.

Members are vetted personally by Narendra, and about 75% of applications are rejected, according to a report in The Wall Street Journal. The site also requires members to regularly submit trading ideas to maintain access to material posted by others.

It is this element of exclusivity that appeals to the Winklevoss twins, who likened the concept to the early days of Facebook, when only people with “.edu” email addresses from certain universities were eligible to join.

The company will move into the Winklevosses' Manhattan office space near Madison Square Park when it opens in October. “We want to get involved and really roll up our sleeves,” said Tyler Winklevoss.

SumZero is the first investment made by Winklevoss Capital, a firm set up using the money from their $65 million settlement with Facebook in 2008.

The Winklevoss twins tried to reopen the case in January 2011, seeking more money. However, a US appeals court ruled that they would have to accept the settlement.

The twins' lengthy battle with Zuckerberg was portrayed in the 2010 film The Social Network, in which the story of Facebook's beginnings at Harvard University is dramatised.