For all the concern and uproar over online privacy, marketers and data companies have always known much more about consumers’ offline lives, like income, credit score, home ownership, even what car they drive and whether they have a hunting license. Recently, some of these companies have started connecting this mountain of information to consumers’ browsers.
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Companies like Acxiom and a competitor, Datran Media, make the connection between online and offline data when a person registers on a Web site or clicks through on an e-mail message from a marketer.
Datran’s cookies include 50 to 100 pieces of information. Both companies say cookie data is anonymous and generalized. Datran and Acxiom then sell advertising on Web sites like NBC.com, Facebook and Yahoo to companies that use their data.
Read more in The New York Times.