Doubleclick / facebook and other companies use these kind of cookies, but it requires to have a snippet of code on each of the sites you want to track. Google for example leaves you a cookie and each time you see an ad block of them google will track the cookie in the browser and the ad script will send your info to a central server. This is very bad for the users privacy, and I don't think you want to go this way, especially not for just a squeezpage, and I don't see how you want to get your script on millions of website just like google/facebook and other socialmedia have.

Doesn't your squeeze page targets a specific branch already? If you want to have more specific data let them use a dropdown, most autoresponders can generate such a form, and create different list for each choice the user made. Having a extra dropdown will reduce your sign-up rate, so I won't advice using it but it is possible.

You should look up the 22 million dollar fine Google got for doing just this. Then you should rethink if you want to even do this

http://www.technocrates.org/google-2...ied-on-safari/