The patent office delivered its ruling late last month but made it public this week. With one of the patents, the decision is what's considered a final rejection, while with another it's considered nonfinal. In both cases, Microsoft has the ability to pursue its claims further.
The rejections come after aof the patents was sought by the Public Patent Foundation, which because there was "prior art," that is, evidence that others had done similar work before Microsoft's patent application. A U.S. Patent Office examiner issued a of one Microsoft patent in September 2004.
Though developed for Windows, the FAT format has become a common means of storing files on all manner of computers, as well as on removable flash memory cards used in digital cameras and other devices. It is also used by the open-sourcethat lets Linux and Unix computers exchange data with Windows computers, and by Linux itself to read and write files on Windows hard drives.
There has been concern that if the FAT patents are upheld, Microsoft may claim that Linux infringes on Microsoft technology and will seek a royalty. Any monetary compensation could threaten the operating system, which under General Public License (GPL) terms may not be distributed if it contains patented technology that requires royalty payments.
A Microsoft representative said Wednesday that the company considers the latest rejections somewhat of a victory because the examiners have rejected the prior-art claims. Microsoft said the latest rejections are centered on how the inventor of the patents is listed.
"None of the prior art submitted by the Public Patent Foundation stood up under examination," Microsoft Director of Business Development David Kaefer said in a statement. "The issues that have come up in these re-examinations have nothing to do with (non-Microsoft) prior art. Instead, the issues involve a question over whom--at Microsoft--should be properly listed as an inventor."
A Public Patent Foundation representative was not immediately available for comment.
Microsoft announcedin December 2003, as part of a stepped-up intellectual-property licensing push. It announced at the time that flash memory seller Lexar Media was taking a license for its FAT format technology.