>> julie brill: absolutely. >> kroft: with names attached to it? with personal identification? brill: the dossiers are about individuals. that's the whole point of these dossiers. it is information that is individually identified to an individual or linked to an individual. >> kroft: do you think most people know this information is being collected? >> brill: i think most people have no idea that it's being collected and sold, and that it is personally identifiable about them, and that the information is in, basically, a profile of them. >> kroft: no one even knows how many companies there are trafficking our data. but it's certainly in the thousands, and would include research firms, all sorts of internet companies, advertisers, retailers and trade associations. the largest data broker is acxiom, a marketing giant that brags it has, on average, 1,500 pieces of information on more than 200 million americans. it's much harder for americans to get information on acxiom. the company declined our request for an interview, and is fairly vague about the methods it uses to collect inf