This should be interesting: Patent Office asked to review Microsoft FAT patent (press release)
According to the Public Patent Foundation‘s request, “the ‘517 patent is causing immeasurable injury to the public by serving as a tool to enlarge Microsoft’s monopoly while also preventing competition from Free Software.” “Microsoft is using its control over the interchange of digital media to aid its ongoing effort to deter competition from Free and Open Source Software. Specifically, Microsoft does not offer licenses to the ‘517 patent for use in Free Software. As such, the ‘517 patent stands as a potential impediment to the development and use of Free Software because Free Software users are denied the ability to interchange media with machines or devices running Microsoft owned or licensed software.”
The [sic] says that Microsoft’s FAT patent (5,579, 517) is invalid because of three prior art patents, filed by IBM and Xerox in 1988, 1989 and 1990. Microsoft was not granted ‘517 until 1996.
Slashdot: PUBPAT Challenges Microsoft’s FAT Patent