If Microsoft was serious about it, they should give some compensation for the cost of the upgrade. Imagine large corporations, tens of thousands of desktops. Imagine how much does it cost to upgrade everyone because Microsoft messed up with some IP. I sincerely don't believe in something like assuming half responsibilities. If you're responsible for something, you should be responsible for the whole. Microsoft is currently only "kind of" responsible for IP issues with the software, which may give some customers the (wrong) impression that they are protected, when they aren't *fully* protected. The open source world is different for several reasons. Open code makes much easier to spot and correct IP violations earlier, which avoids a lot of issues. Being more modular and dinamic, open source applications tend to be much easier to automatically manage in the long run (apt-get comes to mind), which also makes the cost for such kind of migration, if ever needed, smaller than with comparable Microsoft products. As for the legal protection, there's nothing stopping open source vendors (such as RedHat) from providing equivalent legal umbrellas, for a price. But the funniest thing about the whole argument is that the reverse of Microsoft argument is true: by being solely responsible for the IP protection, companies like Microsoft become an easy target. Starting a legal case is also very expensive, and IP hoarders need someone big, someone who they can point a finger at and have a reasonable expectation of making some money of it in the end. It does not make sense to go user after user, it does not scale well. We already have an example with the Unisys GIF case. Unisys tried to actively enforce it, going user after user; they ended up scaling things up, and making more noise than damage. The process sparked the community to create PNG, which lessened the importance of Unisys patents. It's clear that the situation, and the risks involved, are not as clear cut as Microsoft would like us to believe.