I don't think it's hard right now to get information on a visitor's company if they work somewhere large enough to have their own public IP block.
What I would love to know is how they take that and get an email address out of it. Which 3rd party are they working with that 1) had the IP -> email address link, or this guy logged in and 2) is willing to share that data with a 3rd party?
I've been told that, if you buy something online, some vendors sell your information (like email and postal addresses) tied to a 3rd party cookie on your browser.
Now, any site you visit that is able to check that 3rd party cookie knows all about you.
What I would love to know is how they take that and get an email address out of it. Which 3rd party are they working with that 1) had the IP -> email address link, or this guy logged in and 2) is willing to share that data with a 3rd party?