Microsoft FAT patents

Microsoft has a number of patents on how to deal with filename in their commonly used FAT filesystem. These patents have been issued in the USA, Germany, and surely a long list of other countries.

The FAT patents have the interesting property of being useful only for compatibility with the patent owner. The FAT patents are not otherwise useful; in fact the FAT filesystem is technically undesirable. Those who wish to make use of the patent are clearly seeking compatibility, not innovation or other useful properties.

In the USA

In December 2003, Microsoft announced licensing demands of four patents for the FAT filesystem:

• US5,579,517 "The '517 patent"
• US5,758,352 "The '352 patent" (The EPO equivalent is EP0618540 )
• U.S. Patent #5,745,902
• U.S. Patent #6,286,013

Timeline

• Autumn 2003: MS starts threatening people
• September 2004: The '517 patent is rejected thanks to the work of PubPat and others.
• January 2006: The '517 patent is reinstated
• January 2009: Microsoft uses its FAT patents against TomTom

In Europe

The patents granted by the European Patent Office are:

• EP0618550 - upheld in Germany, see below (equivalent to US5,758,352) - Expired on 2014-10-05 ?
• EP0618540 - upheld in Germany by regional court of Mannheim in 2012 Expired 31.03.2014 at the latest (20 year term) in DE, FR, GB. Later this patent was again invalidated by Federal patent court of Germany in Dec 2013
• ...

Upheld in Germany

(See: X ZR 27/07 (2010, April, Germany))

• German appeal court upholds Microsoft FAT patent, The H, April 2010 (also: slashdot story)
• Federal Patent Court declares FAT patent of Microsoft null and void, The H, April 2007 (also: slashdot story)
• German original: WINDOWS - Dateiverwaltung beruht auf, patentfähiger Erfindung (English translations^[?]: Google, bing translator)
• German original: Text of the appeal court decision (English translations^[?]: Google, bing translator)

Related pages on ESP Wiki

• Microsoft
• Microsoft vs. TomTom - where MS forced TomTom to pay for patents, seemingly including their FAT patents
• Litigation
• Example software patents

External links

• How Linus Torvalds Helped Bust a Microsoft Patent, 27 Mar 2012, Wired
• PubPat: Microsoft FAT Patent (page out of date)
• Groklaw report on A patch to remove VFAT filename conversion from the Linux kernel,
  • the LKML thread
  • A related FAQ produced by Andrew Tridgell and Linux Foundation
• Microsoft's IP chief on TomTom, Linux and patents, techflash, Feb 2009