Not that this should come as a surprise to anyone, but a new study is out that shows how much personal information is shared and sold between website and data aggregators. Especially interesting is what dating sites like OkCupid make available to vendors.

Stanford University computer scientist Jonathan Mayer has released a study concerning behavioral targeting and tracking people across the Internet.

As expected, he found that many companies are involved with monitoring every click and then selling and sharing that information to advertisers so they can target you specifically.

Click a local ad on HomeDepot.com and 13 companies get your name and email address. Type the wrong password into WSJ.com and seven companies get your email. Click the validation link in the signup email for a Reuters newsletter and 5 companies get your email.

Interact with classmates.com and 22 companies get your full name; Bleacher Report sends it to 15 companies.

OkCupid, a free online dating website, appears to sell user information to the data providers BlueKai and Lotame, including gender, age, ZIP code, relationship status, and drug use frequency. (emphasis ed.)

I’m all for trading privacy for convenience and tracking people and their actions across the Internet for things like e-commerce, but there is a fine line where tracking becomes an invasion of privacy. Websites and large data providers’ efforts are not widely regulated here in the US (as it is in EU). The ACLU is concerned, as you should be as well.

Besides tracking pot usage (what advertiser needs to know that?), OkCupid tracks pretty basic stuff. If you want to scare yourself, go look at Rapleaf or read how credit card companies are using your purchase history to target your ads.