You can be a "real" company and still be a patent troll. These guys are probably failing and using their patents to get a few bucks before they finally die.
I'd say you are a patent troll anytime you are using a bullshit patent to extort a third party. The rub is what constitutes a bullshit patent, but "sending messages through a map UI" seems obviously in this camp. It sucks you have to spend hundreds of thousands of dollars for the courts to validate this logic though.
So by that definition, I'm sure IBM could be a patent troll, just like any other company with BS IP.