Google has announced plans to stop using tracking cookies on its Chrome browser by 2022, replacing them with a group profiling system in a move the company says will “chart a path to a web more respectful of privacy ”.
The change is significant. Chrome controls about two-thirds of the web browser market. Third-party tracking cookies, on the other hand, underpin much of the targeted advertising industry. And, while Mozilla’s Firefox and Apple’s Safari have already stopped supporting third-party cookies, Google is the first company to offer an alternative advertising medium.
Rather than following and targeting you on an individual basis, Google’s alternative instead groups you into a crowd of people with similar broad-based interests. Google claims that this gives users more privacy. This oddly matches the assurance given to advertisers that the new technique is at least 95% as effective as individual targeting.
But under the death knell of Google’s press releases, the shift from tracking to profiling raises a number of new privacy and discrimination issues. Apparently, a move to bolster individual privacy, Chrome’s new system should ultimately benefit Google, giving the company yet another edge over its beleaguered AdTech competitors.
Recognizing how invasive this tracking has become, EU data protection laws classify cookies as “online identifiers”, subject to regulations requiring websites to obtain your consent before issuing cookies. on your browser.
Google’s new system for Chrome will drop this. The browser will instead use your recent browsing history to generate your “cohort identity”. This is currently achieved by using a “simhash”, which in simple terms generates “magic numbers” to represent your interests before you group together with those in possession of similar numbers.
Hidden within a cohort of a few thousand individuals, you will then have advertisements targeted at your cohort rather than at you as an individual. This is touted as an improvement in privacy, as it moves away from the individualized tracking and targeting that made third-party cookies particularly invasive.
To the Facebook template
Conceptually, the system offered by Google is not new – it is a form of profiling, which enables an advertising model that Facebook has been using for some time. Targeting someone’s cohort identity is like creating an individual-based “look like audience”, a service Facebook currently offers to advertisers.
We should expect profiling to also create a number of different named cohorts, from which advertisers can build custom audiences with mixed interests – which Facebook also offers.
This is where profiling becomes problematic. In 2016, it was revealed that Facebook allowed housing advertisers to exclude users based on their race. Even after Facebook changed its audience groups, it was still possible for advertisers to discriminate based on sensitive interests held primarily by minorities.
Profiling involves machine learning algorithms and AI technologies that repeatedly reinforce real world biases. As such, Google’s decision to sack key members of its AI ethics team as Chrome adopts a profiling advertising model looks particularly alarming.
Aside from the known harms and risks of profiling, it’s unclear how Google’s new model improves individual privacy. For the system to work, Chrome must freely offer the identity of your cohort on any website you visit, while a third-party cookie does not reveal this volume of data to all websites.
The smaller the cohorts, the easier it will be to spot among them. And you’d expect Google to favor smaller cohorts, as larger cohorts naturally lower the accuracy of targeted advertising. Overall, the change will introduce a number of new risks to privacy and discrimination. So why could Google have chosen to delete third-party cookies on Chrome?
Google’s mixed motivations
One of the reasons is regulation. The new EU ePrivacy Directive could abolish the traditional use of tracking cookies in the EU anyway, with serious consequences for other jurisdictions. So Google can just jump before it gets pushed.
By restricting how third party advertising services can use Chrome, Google could also benefit from the fight against competition. An online advertiser interest group has previously asked the UK competition watchdog to report on the Chrome change as part of its existing investigation into Google’s advertising practices. Google itself will retain plenty of tracking possibilities after the change, especially when Chrome users are signed in to their Google accounts.
Google is the biggest beneficiary of Chrome’s shift from cookies to cohorts. Designed as a boon to privacy, Google’s new system only slightly restricts its traditional targeted advertising reach, while adding Facebook’s profiling-based mode of advertising to its repertoire.
End users like you and me, on the other hand, probably won’t notice a difference. We will always be monitored and targeted based on our online activity – only now as part of a group, rather than an individual.
This article by Eerke Boiten, Professor of Cybersecurity, School of Computer Science, De Montfort University is republished from The Conversation under a Creative Commons license. Read the original article.