Facebook has produced what it says is \"smoking gun\" evidence that a New York man\'s claim to partial ownership of the hugely successful social network is a fraud. Paul Ceglia of Wellsville, New York, in a suit filed in June of last year, claimed that he signed a contract with Facebook co-founder Mark Zuckerberg in April 2003 to design a website called \"The Face Book\" or \"The Page Book.\" Ceglia submitted a copy of a contract with Zuckerberg to the court hearing the case in Buffalo, New York. But lawyers for Zuckerberg and Facebook said in a filing with the court on Monday that the submission by Ceglia is a doctored version of another contract between Zuckerberg and Ceglia. That contract concerns work Zuckerberg did for Ceglia in 2003 on a website called StreetFax, which provided a photo database of traffic intersections for insurance adjusters. It makes no mention of Facebook. \"The court-ordered forensic testing has uncovered the authentic contract between Mark Zuckerberg and StreetFax that Ceglia attempted to conceal,\" the Facebook filing said. \"This smoking-gun evidence confirms what Defendants have said all along: the purported contract attached to the complaint is an outright fabrication,\" it said. \"The authentic contract -- which mentions only StreetFax and has nothing to do with Facebook -- was found embedded in the electronic data from 2004 on Ceglia\'s computer,\" Facebook said. Facebook said it would ask the court to dismiss the case on the basis of \"the now-overwhelming evidence of Ceglia\'s fraud, spoliation and subterfuge.\" Facebook lawyers have repeatedly denounced the suit by Ceglia as a \"brazen and outrageous fraud\" and described him as a \"hustler.\" New York state Attorney General Andrew Cuomo accused Ceglia in 2009 of taking more than 200,000 dollars from customers of his wood fuel pellet company and then failing to deliver any products or refunds. Facebook\'s origins have been the subject of two recent books and a hit Hollywood movie, \"The Social Network.\" A pair of Harvard University classmates, Tyler and Cameron Winklevoss, have been involved in a long-running dispute with Zuckerberg over Facebook, claiming he stole their idea for the social network.