Whenever Microsoft makes an agreement with a competitor, its actions are viewed with a fair bit of suspicion. The recent agreement between Novell and Microsoft is no exception. Plenty around the blogosphere wondered aloud where the exploding pens were hidden, and on ZDNet, David Berlind believed that the Novell agreement, coupled with previous agreements with Sun, leaves the way clear for Microsoft to make a full legal assault on both RedHat - vendor of the leading Linux distribution - and open source products in general.
Some degree of suspicion is understandable. No one would mistake Microsoft for a company that is good at losing money. Every agreement Microsoft enters into surely is done with an eye towards whether or not it will benefit Microsoft.
I don't consider that a flaw, however, so much as the mark of a company that is doing what it is supposed to be doing. Furthermore, Novell is doing the same thing. I believe this agreement offers wins to both sides, as I described in a previous post.
There are strong reasons, however, why Microsoft will avoid riding into legal battle against Linux. Here are a few:
1. Patents cut both ways: Microsoft isn't the only one with a patent arsenal. Just as Microsoft has patents it can use against other companies - or open source - other companies with an interest in Linux may have patents they can use against Microsoft. I've described software patents as nuclear weapons that both sides in an arms race acquire as defense against an opponents growing arsenal. Defense, however, is not achieved through launching them against each other, but through the "Mutually Assured Destruction" that would rain down were they ever to actually use them.
A Microsoft that goes after Linux on the basis of patents opens itself to countersuits by companies with an interest in Linux and patents which can be used against Microsoft.
Nobody has more patents than IBM.
2. Long-lasting ill will: It sure looks like Microsoft is working very hard to achieve a detente with open source. They are working with Zend to improve the PHP developer experience atop Windows. They are granting full access to the source code for Windows CE 6.0 (though that benefits Microsoft as much as programmers). They just blessed Mono, an open source version of the .NET runtime, through their Novell agreement.
What's the point of all that if they are just going to light the world on fire with subsequent legal bombs on Linux? There's currently a debate between the pragmatists and the idealists over the wording of the successor to the GPL. Certain quarters even seem to be open to the idea of using Microsoft technology atop - or within - an open source base.
An assault by Microsoft would quickly undermine the cause of the pragmatists and give the extremists the upper hand. Furthermore, I would expect the ill-will created to last about as long as antipathy towards SCO...which means pretty much forever.
I don't see why that would benefit Microsoft.
3. Regulatory oversight: Microsoft doesn't operate in a regulatory-free environment. A Microsoft assault on Linux using the monopoly power afforded by patents would not only awaken regulators in Brussels, but would likely aid the cause of those trying to block a consistent software patent policy in Europe. It's pretty easy to stoke fears of companies using software patents as battering rams if the largest software company in the world starts to use them against its biggest operating system competitor.
To summarize: going on a patent offensive would turn the gains from their agreement with Novell into losses. Microsoft will want to protect their IP, as well as generate revenue from it, but a better way to go about that is by licensing Microsoft-specific technology (like Windows Media formats) or protocols related to Windows interoperability while remembering that Microsoft has made a LOT of money by viewing their patent library as mostly a defensive tool. Patents they may or may not have on core operating system functions are better put in the "defensive" category.
You can generate a lot of profit by maintaining peace with your neighbors...just ask Switzerland. Granted, great empires have been founded through an offensive posture, and the Roman one wouldn't have existed if not for a predilection for conquering nearby civilizations. On the other hand, Microsoft already HAS a great empire built entirely through trade. Why risk it all by creating a pointless war with the open source community?
That's why I doubt Microsoft will do it.