A study by Stanford University Law School's Center for Internet and Society has found that many online advertising networks are not adhering to their own privacy policies and continue to rely on and push out Web tracking cookies even after users have indicated that they do not wish to be tracked.
Half of 64 online advertising firms did not remove their tracking cookies from consumers' computers after they have opted out of behavioral ad targeting. Twelve percent of those firms failed to remove tracking cookies, or continued to place them on consumers' systems even after those consumers opted out of tracking. The study, which was carried out over several months by researchers at the Stanford Security Lab, suggest that voluntary, industry led efforts to reign in unwanted user tracking online may be falling short.
