A New York man suing Mark Zuckerberg for 50% of Facebook has added five attorneys to his legal team. He says a contract he signed with the then-Harvard University freshman Mark Zuckerberg in 2003 which gives him 50% ownership of facebook.

NY man suing for part ownership of Facebook brings in 5 more lawyers as case moves forward - Yahoo! News

Facebook Claimant Says He Has Zuckerberg's E-Mails to Prove 50% Ownership

Ceglia says Zuckerberg sent him numerous e-mails discussing the terms of the contract and the early development of "The Face Book"
Facebook Claimant Says He Has Zuckerberg's E-Mails to Prove 50% Ownership - Bloomberg