Microsoft's Linux-related patents rejected

The U.S. Patent Office has rejected two Microsoft patents over the FAT file format, but the software maker said that it's not ready to give up its battle to protect its widely used method for storing data.

The rejections come after a re-examination of the patents was sought by the Public Patent Foundation, which argued that they were invalid 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 preliminary rejection 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-source Samba software that lets Linux and Unix computers exchange data with Windows computers, and by Linux itself to read and write files on Windows hard drives.