Microsoft Corp. said Tuesday that its patents on technology for saving computer files with familiar names had been upheld after a lengthy challenge.
David Kaefer, a director of business development for Microsoft's intellectual property and licensing group, called a decision by the U.S. Patent and Trademark Office "a validation of the patents." (MSNBC.com is a Microsoft - NBC joint venture.)
Microsoft had faced challenges to two of patents for technology widely used to name files on computers running Microsoft's Windows operating system. Similar technology has in recent years also been used for naming files from devices that work with Windows, such as digital cameras and portable music players.
The patents are part of Microsoft's implementation of a broader system for storing computer files. Microsoft did not claim control over the entire system, called File Allocation Table, or FAT, but rather a specific part that allowed people to give computer files longer, easier-to-remember names.
Since late 2003, Microsoft has been asking companies to buy licenses to use its implementations of the FAT system. Kaefer said the patent challenges had raised concerns for some people who were considering buying those licenses.
The issue is not totally resolved, however. Kaefer said Microsoft also faces similar challenges in Canada and Germany.
Dan Ravicher, executive director of the Public Patent Foundation, one of the Microsoft challengers, blamed the loss on what he called a flaw in the patent system. Under the rules, he said his organization had no opportunity to rebut Microsoft's claims after its initial challenge.
"I still believe that this patent is invalid," he said.