Microsoft FAT patent appeal upheld in Germany

A German appeal court has upheld Microsoft’s controversial patent that describes the means used to store long filenames on FAT file systems without flouting compatibility with old applications.

In 2007 the German Federal Patent Tribunal alleged that patent EP0618540 was difficult to distinguish from work done on the Rock Ridge Interchange Protocol developed in 1991, which allowed long filenames to be used on the ISO9660 file system used on CDs.

However, last Tuesday (20 April) the appeals court* in Germany threw out that argument due to technical differences between the two systems. It found that Microsoft had solved new problems in the FAT file system that the Rock Ridge work hadn’t taken into account.

Redmond’s development of long names on FAT had been created so that legacy applications and systems would ignore the new names, which was considered to be an important distinction by the Karlsruhe-based court.

Microsoft’s patent win in Germany reflects an earlier assessment by the US patent office, which gave the company’s patent number 5,579,517 (which is EP0618540 in Germany) the thumbs up in 2006.

In the past few years Microsoft has been increasingly stomping around demanding $300,000 a pop licence fees from camera, camcorder and digital photo frame makers firms that want to use the FAT and FAT32 filesystems. Meanwhile it has also been charging phone, PC and network vendors wishing to use the format in their devices a volume-licence fee.

So the German appeal court’s decision to have the patent upheld is a significant one for the software giant, because Microsoft is no longer hindered in demanding payment for its means of storing long filenames on FAT file systems. ®

*Translated from German to English - the original text is here.