No, knowledge of infringement is not required to be liable. Proof of "willful infringement" will result in higher damages, but even without willfulness or knowl

No, knowledge of infringement is not required to be liable. Proof of "willful infringement" will result in higher damages, but even without willfulness or knowledge of the patent, you could still face some pretty hefty damages. Part of why patent trolls are so unpopular is precisely because they go after folks who have no reason to suspect they might be infringing. The scanner trolls are a good example of this. [1] [1] http://arstechnica.com/tech-policy/2013/01/patent-trolls-want-1000-for-using-scanners/ http://arstechnica.com/tech-policy/2013/01/patent-trolls-wan...