A judge has told the owners of a social networking site who accuse Facebook of stealing their idea that they need to find more facts to support their case.

Judge Douglas Woodlock told the founders of ConnectU that they had two weeks to find evidence that Mark Zuckerberg, Facebook's 23-year-old chief executive, had the idea for his site while working for them.

Cameron and Tyler Winklevoss and Divya Narendra are suing Mr Zuckerberg for allegedly stealing "the basic idea" for Facebook, the rapidly growing networking site, when he worked for ConnectU as a student at Harvard in late 2003.

Their action accuses Mr Zuckerberg of copying the specific code for Facebook from ConnectU, alleging copyright infringement, misappropriation of trade secrets, and breach of contract.

At a district court in Boston, Massachusetts, yesterday, Judge Woodlock told that ConnectU's founders that they needed to find more evidence for their claims, saying: "Dorm room chit chat does not make a legal contract."

He said the case appeared to be designed to pressure Facebook into an out-of-court settlement, rather than to be won on legal merit. He deferred ruling on the case until August 8.

At a press conference after the hearing, ConnectU's lawyer, John Hornick, declined to say whether Mr Zuckerberg had ever signed a contract while doing work for ConnectU's site, which was then known as Harvard Connection.

Mr Hornick said: "The judge has given us a chance to amend the complaint and add more facts. We have to decide whether to do that or stand on the complaint already filed."

He added that ConnectU was open to settling the dispute out of court, but said that there were no active talks with Facebook along those lines.

Mr Zuckerberg denies any wrongdoing and his lawyers have asked the judge to dismiss the case.

ConnectU first brought the action in August 2004, when Facebook had only 200,000 registered users, and it is only because of procedural delays that it has has not been heard until now.

In March this year, ConnectU's case was dismissed on a technicality, but because the legal merits were not ruled upon, the site's founders filed a new action.

In a response to ConnectU's claims issued before the proceedings, Facebook's lawyers said of the interactions between Mr Zuckerberg and the ConnectU founders: "Only one of the students had an idea significant enough to build a great company. That person was Mark Zuckerberg."