Red Hat, which indemnifies its customers against legal risks and has promised to rewrite any software found to violate others' intellectual property, told its customers on Monday they have nothing to fear.
"The reality is that the community development approach of free and open-source code represents a healthy development paradigm, which, when viewed from the perspective of pending lawsuits related to intellectual property, is at least as safe as proprietary software," the company said in a statement.
Microsoft won't say how much farther out of the scabbard it will pull its saber if the current effort fails to bring forth more patent deals with open-source companies.
"I don't have the answer for that. I have the answer for those that want to be responsible," Guttierez said.
But Microsoft would prefer not to sue, according to Guttierez. "If we wanted to litigate we would have done that a long time ago. Litigation is not an effective way of going about solutions," he said, adding that the company released the tally of potentially infringing patents now only after three years of effort to come up with a "constructive" way of dealing with the situation.
Open source allies call Microsoft's bluff
"I can't see it as any more than a somewhat hollow anti-open-source charade," said Matt Asay, vice president of business development for open-source document management start-up Alfresco. "If they want to really get people buying into their patents, they've got to put forth some substance ... They haven't shown what the patents are or what they cover."
Larry Augustin, a venture capitalist who grew wealthy off a Linux-related initial public offering, told Microsoft on his blog to "put up or shut up." "If Microsoft believes that free and open-source software violates any of their patents, let them put those patents forward now, in the light of day, where we can all evaluate them on their merits," Augustin said. "If not, then stop trying to bully customers into paying royalties to use open source."
Litigation is unlikely, said Brian Kelly, an intellectual property attorney with Manatt, Phelps & Phillips: "If the end game is a lawsuit, you probably lead with a lawsuit."
Of course, SCO Group did lead with litigation in 2003 when it took on IBM with claims that Big Blue violated its contract by bringing proprietary Unix technology to open-source Linux. But Linux continues to spread widely despite that case -- even with SCO suing actual customers.
At the same time, open-source allies are accumulating more legal heft by banding together and signing up some of the computing industry's largest companies. Oracle now sells its own version of Linux, and Sony, Red Hat, IBM, Novell and Philips formed the Open Invention Network in 2005 to try to amass a patent counterweight. Patent holders who join the organisation or license its patents agree not to sue over patents in the "Linux environment."
Even if Microsoft doesn't sign any more patent pacts, just slowing down the competition could be counted as a victory. Illuminata analyst Jonathan Eunice, in a blog posting Monday, likened Microsoft's patent threat to Iraq's use of Scud missiles in the Persian Gulf War.
"The point wasn't to actually use the weapon, but rather to require opposing forces to plan and take countermeasures against the possibility of use," he said. "While they were so occupied, they were less effective doing other things."
CNET News.com's Ina Fried contributed to this report.
How could the linux kernel infringe MS patents?
It was released in 1991 when Windows was still wearing nappies (and I can tell you - version 3.0 was very crappy and really needed nappies!)