A Question (Score 1)

I realize that I am asking a loaded question but: Has Microsoft ever actually sued anyone over patents? Not in response to being sued (between governments and sharks, there have been a few of those), but as a first strike. I have heard of cross patent "agreements" but never an actual lawsuit. I went searching around and couldn't find any; alas searching for something like this is harder than I thought.

Disclaimer: I work for Microsoft but they don't own me, they are just renting my mind and fingers ;-)