The News Minute | October 22, 2014 | 4.45 pm ISTFacebook has sued several law firms, including the world’s biggest business law firm DLA Piper, for representing a man who claimed to own half of the social network.Paul Ceglia claimed that he and Facebook CEO Mark Zuckerberg had signed a contract in 2003 by which he was entitled to half the ownership of the company, Sky News reported.The case filed by Ceglia against Facebook was dismissed by a court in April. Ceglia is now facing criminal charges for having doctored and destroyed evidence to support his claim over Facebook. Facebook lawyers allege that the lawyers and the law firms who represented Ceglia conspired against the social network. In a suit filed in the New York State Supreme Court, the Facebook lawyers claim that the lawyers of Ceglia “knew or should have known†that the lawsuit was fraudulent and “based on an implausible story and obviously forged documents.â€Facebook is claiming money for the damage caused to its reputation because of the fraudulent suit and also reimbursement of the expenses it incurred in defence of the same.