Well, I'm not sure why that would matter either, just because I simply don't know if it would matter or not. I think that if it is something that is important to *them*, they will ask.
Now, purely from a sales pitch point of view:
-If you find you are dealing with someone who would be impressed by that information, it does make your line sounds more professional and desireable somehow.
-It also shows your intent is to be in this for the long haul, and you are taking your venture very seriously. If they were deciding between you and another person who didn't register their mark, it could show earnest.
Just my 2 pennies worth, which ain't much these days. I hope any of this helps, they are just random thoughts. Best of luck to you...