Microsoft has two goals from its patent licensing program. One is to create a new, stable revenue stream to complement its ageing cash cows, Windows and Office. Patent royalties could provide an attractive income if the company succumbs to market economics, and is forced to lower its prices to compete with cheaper free software. The other goal - although it may simply be fortuitous collateral damage from Redmond's point of view - is to make writing free software illegal. Or if not illegal, then so fraught with legal uncertainties that developers gravitate away from the GPL.

GPL developers shy away from patent minefields citing two reasons. Many say patents are incompatible with the license while others cite more practical concerns: saying that the prospect of expensive legal battles is a risk small developers can't take. So when Microsoft hired Marshall Phelps, the IBM executive and lawyer responsible for building Big Blue's royalty income from zero into a multi-billion dollar business, community leaders sat up and took notice.

Last December Microsoft announced its first-ever patent royalty program. Camera and PDA manufacturers were invited to pay Redmond a peppercorn royalty for use of the FAT file system, which they'd previously used for free. But now that first tentative foray has been dealt a setback, as the US Patent Office is to open an investigation into the validity of Microsoft's FAT patent (renewed in 1996).

Prior art from Xerox and (ironically) IBM submitted by the Public Patent Foundation raises "a substantial new question of patentability" according to the USPTO. Although the PPF points out that patents are rejected in about 70 per cent of re-examinations, it cautions that this is just the first step in the process. And, of course, there are plenty more patents where FAT came from.

Still, it's an indication that the software libre community doesn't just spend its time congratulating itself, and can organize to repel clear and present danger. ®

External links

Public Patent Foundation
FAT File System Technology and Patent License [Microsoft] How smart is reverse engineering .NET?

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