Advocacy Group Goes After Microsofts FAT Patent

The Public Patent Foundation is asking the patent office to revoke one of Microsoft's FAT file system patents, saying it is invalid and that Microsoft's licensing of it raises competitive concerns.

A patent advocacy group is seeking to have one of Microsofts patents for its file allocation table (FAT) file system revoked, alleging that the patent was wrongly issued and is hurting competition.

The Public Patent Foundation announced on Thursday that it submitted a request for a reexamination of the patent, No. 5,579,517, to the U.S. Patent and Trademark Office. The patent is one of at least four covering the FAT file system for which Microsoft began offering an intellectual property license in December.

The New York-based group presents in its filing three examples of prior art, the legal term for whether an invention existed prior to the filing of a patent, as the basis for a reexamination. It also alleged that the patent "is causing immeasurable injury to the public by serving as a tool to enlarge Microsofts monopoly while also preventing competition," according to a PDF copy of the request on the Public Patent Foundations Web site.

"Microsoft is using its control over the interchange of digital media to aid its ongoing efforts to deter competition from Free and Open Source Software," the request states.

A patent office spokeswoman on Friday could not confirm whether the office had received the request yet but said that a decision on whether to grant a request for a patent reexamination typically takes between two and three months.

Microsoft officials said the Redmond, Wash., software maker had yet to review the reexamination request.

"Were unfamiliar with this organization and unclear why they are so interested in this one patent," a Microsoft spokesman said in a statement. "Weve signed a number of licensing agreements and our licensing is available to anyone, including companies that sell open source software."

But the foundations executive director and founder, Dan Ravicher, said that by charging for the license, Microsoft leaves out developers of open-source and free software.

"Although some may say that the fee Microsoft charging is low, the fact they are charging any royalty at all means they are expressly excluding free and open source software development," Ravicher said.

Ravicher said that Microsofts decision to license the FAT file system without a royalty-free option for open-source or free software led the group to examine the FAT file system patents. It chose to focus on the earliest one, issued in November 1996, because if the patent office finds it invalid that would make it more likely that the later patents could be revoked as well, he said.

The Public Patent Foundation is a non-profit organization whose goal is to protect the public from potential harm from wrongly issued patents and what it considers unsound patent policy. Its board of directors includes the general counsel for the Free Software Foundation, Eben Moglen, who is also a law professor at Columbia University.

The FAT file system license was one of two that Microsoft launched when it kicked off its common IP licensing initiative. The other was its ClearType technology. Microsoft charges a royalty for the FAT file system of about .25 per device with a cap of $250,000.

The company has created a Web site detailing its IP licensing policy.

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