There are other reasons Microsoft might have a hard time trying to gain its patent rights in a courtroom. For instance, there is the Open Invention Network. It was set up in 2005 by IBM, Sony, Philips, Novell, Red Hat and NEC. Its whole purpose is "to promote Linux by using patents to create a collaborative environment...Patents owned by Open Invention Network are available royalty-free to any company, institution or individual that agrees not to assert its patents against the Linux System," according to OIN's web site.

OIN already has an impressive list of more than 100 patents which it owns. It also has an easy-to-fill-out form page for anyone who wants to sell or donate a patent. With a growing portfolio to its own credit, OIN seems quite prepared to file a counter suit should Microsoft make the mistake of assuming, for example, that Red Hat is an easy target for a patent lawsuit.

Certainly OIN wasn't daunted by the Fortune article. Jerry Rosenthal, OIN's chief executive officer, says the article's whole purpose was to perpetuate "unwarranted fear, uncertainty and doubt among current and potential Linux users and distributors." He pointed out that there never has been a patent lawsuit against Linux, and that the open source operating system "has excellent intellectual property vetting."

Meanwhile, in an article that appeared in Information Week, Linus Torvalds, the force behind Linux, responded to the Fortune piece with something approaching scorn. "It's certainly a lot more likely that Microsoft violates patents than Linux does," he said. "Basic operating system theory was pretty much done by the end of the 1960s. IBM probably owned thousands of really 'fundamental' patents. The fundamental stuff was done about half a century ago and has long, long since lost any patent protection." He would like to see Microsoft name the patents it thinks are being violated. Then the patents can be either struck down if they are bad, or coded around if they're strong enough to stand.

Torvalds thinks Microsoft's bluster is a sign of weakness. "So the whole, 'We have a list and we're not telling you,' itself should tell you something. Don't you think that if Microsoft actually had some really foolproof patent, they'd just tell us and go, 'nyaah, nyaah, nyaah!'" To be quite honest, one can almost picture Steve Ballmer doing just that, at least in private.