> Think of it this way: Your argument for giving someone a BSD licensed piece of software and then suing them over patents in it is "Yeah, I explicitly granted them the right to "freely redistribute and use it", but i didn't really mean for them to be able to do so"

Lawyers are a conservative bunch. So I'm sorry, I just don't believe that a lawyer would be so rash as to allow his client to expose himself like this.

But let's get down to brass tacks. Has there been any significant case law supporting this position?

A. We are not all conservative, we are risk managers. That is not the same. In this case, the risk is low. As for "allow a client", i think you are confused. Lawyers analyze and assess risk and legal implications. We tell this to the client. The client gets the final say, and makes business decisions. If you live in a world where you need a lawyer's permission to "expose yourself like this", i suggest you run :)

B. Yes. A lot, at least in the US (other countries, more questionable). The general principle you are looking for is "legal estoppel". You don't get to promise people they can use something, and then try to stop them legally when they do. This is true whether it's patents or contracts. While most deals of the patent cases deal with sales, the case law is fairly clear on this exact point (IE that unless you explicitly disclaim an implied license, you won't get to give something to someone to use and then claim using it violates your patents). It just would be legal estoppel for a different reason other than sale.