Paul Ceglia claims he had a website development contract with Facebook in 2003, giving him a 84% stake in the company. He filed a breach of contract lawsuit in New York and has been granted a temporary restraining order preventing the company from transferring assets. Facebook is seeking to move the case to federal court, and calls the claim frivolous.
Mark Zuckerberg did not procure the domain name for Facebook’s first site, thefacebook.com, until January 2004. Ceglia claims he and Mark Zuckerberg entered into a contract on April 28, 2003 in which Ceglia agreed to provide some website work in exchange for 50% of the resulting entity, plus an additional 1% every day until the work was completed. According to Ceglia, this amounts to 84%. Ceglia was accused by New York Attorney General Andrew Cuomo last year of defrauding customers in an unrelated wood-pellet fuel business.
Sources:
http://www.businessinsider.com/does-paul-ceglias-facebook-ownership-lawsuit-have-merit-2010-7