Public Patent Foundation

Representing the Public's Interests in the Patent System




PUBPAT NEWS > PUBPAT Challenges Microsoft Patent to Protect Competition in Software Markets



April 15, 2004


PUBPAT challenges microsoft patent to protect competition in software markets: Patent Office Shown New Evidence Proving FAT Technology was Obvious


NEW YORK -- The Public Patent Foundation filed a formal request with the United States Patent and Trademark Office today to revoke Microsoft Corporation's patent on the FAT File System, touted by Microsoft as being "the ubiquitous format used for interchange of media between computers, and, since the advent of inexpensive, removable flash memory, also between digital devices."  In its filing, PUBPAT submitted previously unseen prior art showing the patent, which issued in November 1996 and is not otherwise due to expire until 2013, was obvious and, as such, should have never been granted.


"Microsoft is using its control over the interchange of digital media to aid its ongoing effort to deter competition," states PUBPAT's Request for Ex Partes Reexamination of U.S. Patent No. 5,579,517.  "The ‘517 patent is causing immeasurable injury to the public by serving as a tool to enlarge Microsoft’s monopoly while also preventing competition."


Last fall, Microsoft began to demand royalty bearing licenses for the entire portfolio of patents around the FAT File System.  However, the fact that Microsoft has not offered licenses for use in Free and Open Source Software has led some to speculate that Microsoft intends to use its patents to fight the competitive threat posed by Free Software.


"We'd like to give Microsoft the benefit of the doubt and believe that they are not adopting a strategy of foreclosing competition through the use of dubious patents," said Dan Ravicher, PUBPAT's Executive Director and Founder.  "Unfortunately, their past anticompetitive behavior combined with their recent launch of a comprehensive patent assertion campaign causes us to have serious concerns about their intentions."


Although PUBPAT's filing only directly deals with one patent, the fact that it is the oldest of the patents in the FAT File System portfolio makes it more likely that, once it is held invalid by the Patent Office, each of the other patents will be viewed similarly.


"In the end, our beef is not with Microsoft per se," says Ravicher.  "It's with our broken patent system that is completely failing to ensure only deserving patents get issued."

The Request for Reexamination can be found at PUBPAT Activities > Protecting the Public Domain.




Daniel Ravicher, Executive Director, Public Patent Foundation: 212-545-5337;;




The Public Patent Foundation ("PUBPAT") is a not-for-profit legal services organization working to protect the public from the harms caused by the patent system.  PUBPAT provides the general public, particularly those persons or businesses otherwise deprived of access to the system governing patents, with representation, advocacy, and education.  To be kept informed of PUBPAT News, subscribe to the PUBPAT News List by sending an email with "subscribe" in the subject line to



home  --  activities  --  support  --  news  --  about  --  contact  --  your privacy