Google starts first test with controversial Privacy Sandbox against tracking cookies

For the first time, Google is starting a hands-on test in Chrome of its new Privacy Sandbox advertising system. That project consists of multiple APIs that allow users to see personalized ads without tracking cookies. The first API is now being tested in the browser.

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Google writes in a blog post that it starts with a small-scale test. It is a trial with Federated Learning of Cohorts , or FLoC. That is one of the few parts of Privacy Sandbox that Google has made a practical implementation of until now. With FLoC, advertisers can approach users without using tracking cookies. Users are divided into cohorts based on their interests based on websites they visit. That’s calculated locally in the browser, which Google says is a privacy-friendly alternative way to reach users without following them across websites with tracking.

The FLoC test takes place among ‘a small number of users’ in various countries, including the US. Users from the Netherlands, Belgium or other European countries are not covered by the test. This probably has to do with privacy legislation, because it is not yet clear how exactly FLoC should work in combination with permission as defined under the GDPR and the e-privacy rules.

In the future, the test will be rolled out worldwide, Google says, but the company does not provide a timeline for this. Users who block third party cookies in Chrome are not included in the test. In April, Chrome will get new settings that allow users to unsubscribe from FLoC.

All things for which third-party cookies are currently still used will have to be replaced in due course. Privacy Sandbox consists of several other APIs besides FLoC that all have different purposes. There are APIs to measure conversion, but also for practical matters such as DoS protection. Google itself says that FLoC is 95 percent effective in reaching customers for advertisers, but the public tests must show whether this is really the case.

FLoC and Privacy Sandbox are not uncontroversial. Market authorities and civil rights movements are afraid that Google is taking too much power. An investigation has therefore already been started in England . The influential EFF previously called Privacy Sandbox “a terrible idea .”