Facebook Inc has won access to computers, files and emails it hopes will prove an upstate New York man's claim to own half of founder Mark Zuckerberg's stake in the world's largest social networking company is a fraud.

A federal judge in Buffalo, New York ordered the man, Paul Ceglia, to turn over the materials by August 29 for review by Facebook's experts, including ink sampling.

Ceglia must also provide a sworn affidavit about their contents, as well as other materials he claims not to have, but which Facebook wanted its experts to review. These include storage drives that Facebook believes contain a scanned image of the actual contract between Ceglia and Zuckerberg.

After the materials are handed over, Facebook would have 30 days to review them. It would also turn over various emails between Zuckerberg and Ceglia, according to Thursday's order by U.S. Magistrate Judge Leslie Foschio.

At issue is the authenticity of an alleged 2003 contract under which Ceglia said he hired Zuckerberg, then a Harvard University freshman, to work on StreetFax.com, a street-mapping website intended for the insurance industry.

Ceglia believes this contract also entitled him to a stake for another project, The Face Book, in exchange for $1,000 of start-up money.

He said that project became Facebook, giving him a stake now believed to be worth several billion dollars.

But in a court filing this week, Facebook repeated that this contract was a fabrication, and also released a copy of what it called the actual contract between the men.

It said this smoking-gun evidence, embedded in electronic data from 2004 on Ceglia's computer, makes no mention of Facebook, and instead mentions only StreetFax.com.

Facebook spokesman Andrew Noyes declined to comment. The lawyers Orin Snyder and Jeffrey Lake, who respectively represent Facebook and Ceglia, did not immediately respond to requests for comment.

Ceglia is a wood pellet salesman from Wellsville, New York, and now reported to be living in Ireland.

He has had prior run-ins with law enforcement, including in 2009 when then-New York Attorney General Andrew Cuomo accused him of fraud and shut his business.

Facebook is based in Palo Alto, California, and may be worth $69.2 billion according to SharesPost Inc, which tracts valuations of private companies. Many analysts expect Facebook to conduct an initial public offering as soon as next year.

The case is Ceglia v. Zuckerberg et al, U.S. District Court, Western District of New York, No. 10-00569.

(Reporting by Jonathan Stempel. Editing by Robert MacMillan)

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