Study Shows Why Self-Regulatory Web Tracking Opt Out Programs Won't Work

A new test has found many discrepancies between what advertising companies say in their privacy policies regarding web tracking and how they act in reality.

The test was performed by researchers from Standford's Center for Internet and Society using a new web measuring platform developed to analyze the enforcement of web tracking opt-outs.

The researchers began by looking at members of the Network Advertising Initiative (NAI) self-regulatory program which allows consumers to opt out of behavioral advertising.

It's important to point out that behavioral advertising is not the same as web tracking. While web tracking can mean a simple cookie with an unique identifier that tells websites users have  been there before, behavioral advertising collects information about their web browsing habits in order to determine what ads would be more relevant for them.

NAI members agree to honor behavioral advertising opt-outs, but don't guarantee they will also stop tracking users, except for some of them which explicitly state so through their privacy policies.

"We identified seven companies that promise to stop tracking when a user opts out, but nonetheless leave their tracking cookies in place," says Jonathan Mayer, one of the researchers involved in the project.

"Of the 64 companies we studied, 33 left tracking cookies in place after opting out," he added. However, ten networks removed tracking cookies despite not promising to do so. They include Google and Yahoo.

Only two companies honored Do-Not-Track requests. One deleted its tracking cookies and set an opt-out one, while the other didn't modify its existing cookies but didn't delete them either.

Advertisers argue that do-not-track legislation that would force companies to honor people's requests is not necessary because the industry is capable of regulating itself through programs like NAI.

The reality, however, as outlined in this test, is that if left to decide for themselves, advertising companies will act inconsistently in applying opt-out regulations, further adding to the complexity of the process. Right now, in order to opt out of behavior advertising, users need to visit the NAI website and set special cookies for each of the 75 participating members.