I still haven't recived a second letter..They must have updated their lists because the first letter I recived they sent me a letter for a domain that had never had a website on it. So I called them about it to see how I was violating their patent by a url that was a 404.. lol and they didn't have a clue as what to say..
I guess they were covering the just incases. So maybe they have a opt out section on their spam list..
That or I just haven't gotten a second letter.