The infamous Winklevoss twins, Tyler and Cameron, are now engaged into the social networking business following their legal battles with Facebook co-founder Mark Zuckerberg, leaving the two $US65 million richer.

The Wall Street Journal reported on Sunday that the identical duo had put up the Winklevoss Capital on February 2012 and picked out SumZero as their initial investment venture, possibly to multiply their personal wealth.

For the new social media site, which Reuters said exclusively caters to professional investors, the Winklevosses poured $1 million to finance a business model that is akin to The Harvard Connection, the same site they accused Mr Zuckerberg of copying en route to the establishment of Facebook in 2004.

SumZero was started four years ago and mainly run by Divya Narendra, who was with Tyler and Cameron in the long-running legal dispute with Facebook that ended only in 2011 when the U.S. Supreme Court ruled in favour of Mr Zuckerberg.

All are former students of Harvard University.

The WSJ report has indicated that SumZero currently counts total membership of 7,500 users, with Mr Narendra reportedly vetting each applicant of the 'business club'.

SumZero has been designed to attract 'buy side' investors, in which they can swap innovations, ideas and techniques on trade crafts, Reuters said. Also, 'sell side' analysts are barred from joining the elite circle.

Aside from firing up the funding requirements of their new business initiative, the Winklevosses told The WSJ they would want to be an active participant in further developing SumZero's prospects.

"We want to get involved and really roll up our sleeves," Tyler was quoted by the U.S. publication as saying.

The new venture, according to The Atlantic Wire, is the brothers' departure from their previous preoccupation of giving loads of headaches to Mr Zuckerberg, who they once employed to finish an ill-fated university project.

In an apparent declaration that they were moving on after realising that court decisions will no longer weigh on their side, the twins said in an earlier statement this year: "The time was right for us to pursue our other passions."