Yes, They Really Know It's You

As we've described in previous posts, the ACLU is very concerned about the new model for internet advertising, called behavioral targeting. Behavioral targeting essentially consists of tracking consumers — that means you — around the web, monitoring every click and then selling and sharing that information to advertisers so they can target you specifically.

Stanford University computer scientist Jonathan Mayer released a study today further illuminating scope of this problem. He found that websites are widely sharing your log in name and personal information (like your first and last name and birthday). For example when you view a local ad on the Home Depot website, your first name and email address is sent to 13 additional companies. The site okcupid.com packages your gender, zip code and date of birth especially for advertisers. Advertisers then routinely combine this information into profiles on individual consumers.

Mayer's research emphasizes that we are frequently individually identifiable on the web using a variety of techniques. This personal information is almost completely unregulated which raises some fundamental privacy questions. Should anyone have the right to know and sell to others the fact that you are overweight, or depressed , or gay? These are all commonplace occurrences with both marketers and social networking sites routinely making and selling these determinations.

Advertisers also sell this information to third parties, called data aggregators, who in turn sell it to other marketers, employers and, perhaps most chillingly, the government. As far back as 2001 data aggregation companies have had contracts with the federal government and states to collect and share personal information about millions of Americans, including unlisted cell phone numbers, insurance claims, driver's license photographs, and credit reports. One company boasts it is:

"the silent partner to municipal, county, state, and federal justice agencies who access our databases every day to locate subjects, develop background information, secure information from a cellular or unlisted number, and much more."

It's not clear if the government is accessing our behavioral targeting information. However it is clearly housed in the same systems and with the same companies.

Perhaps most worrying of all is the larger system that's being created. Behavioral targeting creates an economic incentive for tracking — better and better surveillance is rewarded with more and more ad revenue. Of course we have long been concerned with big brother spying on us but what if the danger is here is that lots of "little brothers" all with their own economic reasons for spying. The way the system is built right now, the government can just come along for the ride.

The ACLU believes at a minimum consumers should always be able to opt out of this type of tracking. That's why we favor legislation by Senator Rockefeller that would create a "Do Not Track" mechanism allowing consumers to be legally protected from tracking if they so choose.

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