Facebook is in court to defend yet another claim to ownership, this time from a web designer cum wood pellet distributor who says a previous contract entitles him to 84% of the company.

Filed in the Supreme Court in New York’s Allegany County last month, the lawsuit details how Paul Ceglia signed a contract with Facebook in April 2003 to design and develop the website TheFacebook.com for an agreed ,000 (£665) fee and a 50% stake in the site.

The contract stipulated, Ceglia claims, a further 1% stake for each day until the site was finished on 4 February 2004. Facebook is valued at an estimated .5bn, so an 84% share would be worth around .46bn.

Following Ceglia’s lawsuit, acting New York Supreme Court justice Thomas Brown issued a temporary restraining order that blocks Facebook from transfering assets. The case has now transferred to a federal court and Facebook is trying to have it annulled.

Facebook dimissed the case as “frivolous” and “outlandish”, said it will fight it vigorously and pointed out that a lawsuit over a contract broken in 2003 is “almost certainly barred” by the statute of limitation.

There are a number of reasons that success for Ceglia sounds unlikely – not least waiting until the site reaches 500 million global users before bringing his case, waiting until the outcome of the (successful) Winklevoss claim and the rather bizarre sidenote that a restraining order was granted against him in 2009 by an attorney who alleged Ceglia had defrauded customers of his wood-pellet fuel business to the tune of 0,000.

But imagine, for a minute, that Ceglia succeeded, and moved in to take 84% of Facebook. We might have a new entrant in the MediaGuardian 100…

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