He did post where they failed but hadn't realized it at the time of pasting the Pubpat information LOL

Microsoft claims it developed FAT in 1976 and was granted a patent on the file system in 1996. But some in the industry, particularly those with interests in developing and promoting open-source software, have disputed the FAT patents Microsoft holds. Microsoft licenses FAT to third parties, who must pay the software company to use it in their technology, Payer said.

Both the Public Patent Foundation, or Pubpat, and a California man named David L. Hoffman requested separately that the patents covering FAT be reexamined by the USPTO. Pubpat made its request in April 2004, and Hoffman made his in January 2005, according to USPTO documents.

The USPTO initially rejected patent 5,579,517 in September 2004 after reexamination, but Microsoft submitted more materials to support its claim on the patent.

The decision unveiled Tuesday is the USPTO's final decision, according to USPTO documents. The upholding of the patents means that Microsoft can continue to license FAT to third parties for a fee.

http://www.infoworld.com/article/06/01/11/73790_HNmsfatpatents_1.html

Microsoft FAT Patent