Analysis Microsoft's recent decision to pursue a royalty-bearing licensing strategy, which includes its internally developed FAT Allocation Table (FAT) file system (define), is stirring up new theories in the technology world.

Where many industry watchers applauded the move by the world's largest software company to open up its intellectual property, others saw it as a move to put a stumbling block in the way of Linux, the open source operating system whose growth threatens the dominance of Windows.

Readers at popular online forum Slashdot.org weighed in with the claim that the licensing policy was the beginning of Microsoft's efforts to shut down Linux. The newly-launched Public Patent Foundation is urging the United States U.S. Patent and Trademark Office to re-examine what it claims are "wrongly issued" patents, primarily in response to Microsoft's new IP policy.

Like many operating systems (define), Linux uses the FAT file system technology to keep track of and transfer data from one location to another, whether it's from one computer to another or from a flash memory card in a digital camera to the PC. It's beneficial to users because it allows them to plug in a device without having to reformat it every time they switch to another OS or device.

Linux support for FAT32, used in today's systems, started with the 2.0.34 kernel.

According to the policy letter posted to its site, Microsoft isn't making anyone sign a licensing deal to use the technology, only those manufacturers who want "to standardize the FAT file system implementation in their products, and to improve file system compatibility across a range of computing and consumer electronics devices." With the license, companies get some reference source code and test specifications.

David Kaefer, Microsoft's director of business development, intellectual property and licensing, stressed the voluntary nature of the FAT license if companies or individuals are only calling on this technology in Windows.

"These companies are already covered by our software developer kit program (SDK)," Kaefer said. "However, if they would like to build their own implementations of Windows services, then they may need a license."

Commercial Linux vendor SuSE Linux isn't worried about having to pay for a FAT license. Joseph Eckert, SuSE Linux spokesperson, said, "We are only accessing FAT32 file systems, not using them. This licensing program is of little interest to SuSE."

Microsoft critics, however, point that the technology has been around for nearly 20 years and question the decision to suddenly charge a quarter per unit or $250,000 for using FAT, years after it became an industry standard.

Although Microsoft stands to make millions licensing expanded FAT compatibility for manufacturers, the policy wasn't driven by the bottom line. Officials have said the licensing policy is not expected to have any material impact on its revenue outlook.

Kaefer said every IT company recognizes the need to balance a royalty-free and royalty-based IP program. Microsoft itself licenses technology from other companies, and asked several other companies what they thought the license was worth.

The focus of Microsoft's IP program, Kaefer said, is to adopt the norms that are already standard with IBM and Hewlett-Packard , two companies that combined, hold tens of thousands of patents.

"While we won't make significant money from this license, it will offset other costs and help fund future rounds of research and development," Kaefer said. "Many people have focused on the patent rights we are granting through the license, but the FAT specification, sample code and test specs we provide also have value in their own right."

Manufacturers likely won't mind, according to Sean Wargo, director of industry analysis at the Consumer Electronics Association. For the large companies, the capped $250,000 fee wouldn't even mean a price boost for consumers.

"That sounds low enough that the manufacturer may eat it," he said. "Memory's already getting fairly inexpensive, so something at that cost is probably a blip on the radar for consumers. It's a one-time adjustment that they wouldn't even notice."

The fact of the matter, however, is that FAT itself is not being licensed, but technology that has been built up around the original code. The license covers four patents, they are:

• 5,579,517 "Common name space for long and short filenames"
• 5,745,902 "Method and system for accessing a file using file names having different file name formats"
• 5,758,352 "Common name space for long and short filenames"
• 6,286,013 "Method and system for providing a common name space for long and short file names in an operating system"

All four of these patents deal with the virtual FAT (define), a system driver that acts as an interface between an application and system's FAT. One of the limitations of the FAT file system technology is that you can only store files with eight-letter words; VFAT allows for the longer file names we are used to today.

Even if Microsoft were to levy a charge against everyone, not just the manufacturers, under the current licensing policy, it would only affect the use of VFAT technology. Companies who wanted to continue using FAT and avoid the license fees could do so by taking out the VFAT system driver and forcing customers to come up with eight-letter filenames.

Joe Wilcox, Jupiter Research Microsoft analyst (Jupiter Research and this Web site are owned by the same parent company), said the licensing deal also doesn't affect programmers that reverse-engineered a FAT look-alike, but is for companies that want to increase the compatibility with Microsoft's own FAT schema, nothing more.