by Chris Sorensen, Maclean’s 

Companies are using your private information to make sure you pay more, and see less online

You may have never heard of Choicestream, Criteo or m6d, but if you’ve ever looked at a pair of shoes on Zappos.com, odds are they know something about you. They are just three of 13 firms that are notified by the online retailer when you land on its home page. Similarly, a visit to CNN.com is tracked by eight sites operated by third-party companies, while Dictionary.com informs 12 others about your presence on its site. In almost all cases, the companies are in the business of tracking, measuring and analyzing consumer behaviour on the web, mostly through the use of cookies (tiny pieces of code that websites install on your computer), allowing advertisers to target you with personalized ads for products and services.

It’s called “behavioural tracking,” and it has ballooned in recent years. A recent study by the Berkeley Center for Law and Technology at the University of California found the web’s top 100 sites left a total of 5,795 cookies on its test computer this year, compared with 3,602 three years ago, a 60 per cent increase. Another study by data-management company Krux Digital found that a visit to an average web page triggered an average of 56 instances of data collection in 2012, up from 10 instances in 2010. “I look at this picture and it freaks me out,” Gary Kovacs, the CEO of Mozilla, recently told a packed auditorium as he unveiled a new plug-in for the company’s popular Firefox browser that allows users to “track the trackers” and see the results in a nifty graphical interface. “I’m being stalked across the web.”