
After widespread opposition from the rest of the internet, Google is putting an end to its “FLoC” plans.
The company wants to get rid of the third-party web cookies used for ad tracking, so it proposed FLoC (“Federated Learning of Cohorts”), which would have allowed the browser to track you for the benefit of ad companies. Now that FLoC is dead, Google is pushing another proposal to track users for advertisers. This time the system is called the “Topics API”. There are currently no implementation details, but Google has posted information about the Topics API in a blog post, in developer documents, on a GitHub page, and on a “Privacy Sandbox” site.
Google’s Topic API plans are now being shared with the world, and the company says the next step is to build a pilot implementation and collect feedback from the web. Hopefully, the EFF, Mozilla, the EU and other privacy advocates who spoke out about FLoC will join Google’s new plan. The Topics API gives users more control over the tracking process, but if your main complaint was that browser makers shouldn’t build user-tracking technology directly into the browser for the benefit of advertising companies, you’ll still find flaws in the plan. google. Google is the world’s largest advertising company and uses its ownership of the world’s largest browser to embed its business model into Chrome.

So what’s the difference between the Topics API and FLoC? Both allow the browser to track you and your interests and report those interests to advertisers when they request it, leading to ads with higher click-through rates. Topics give users a little more control over how this process takes place and should make users less individually identifiable. Google says Chrome’s settings show users what topics the browser has detected they’re interested in, and allow users to remove topics they don’t want to see ads for. Most importantly, Google says that users and sites can opt out of the Topics API.
FLoC worked by grouping people with similar browsing histories into a “cohort” and would make assumptions about that group for advertising purposes. One of the concerns was that these groups could be small enough to track users individually, which is what third-party cookies do today. Google says Topics should be broad enough to ensure users are not individually tracked and to further reduce fingerprinting. Google says that “5 [percent] of the time a random topic (chosen from the full range of topics) is provided.”
A full list of initial topics is available here; it contains categories such as ‘Football’, ‘Politics’ and ‘Software’. Google says topics will be public, controlled by people, and their scope will avoid sensitive areas such as ethnicity or sexual orientation. Behind the scenes, the system works by assigning website hostnames to different topics, and as you browse the web, your browser will compile a local list of your topics. When an advertiser asks for a list of topics, the browser shows one topic from each of the past three weeks of use. Google suggests that advertisers “only receive topics they’ve seen” from other sites. So if you visit a knitting website and it has Google ads, then only other sites with Google ads will know about your knitting habits.

Everything here is an improvement over the current free third-party cookies, which can track users individually as they move around the internet. Other browser vendors have addressed the issue by completely blocking third-party cookies by default; Mozilla did that in 2019, and Apple’s Safari started in 2020. The only reason Chrome hasn’t followed suit is because 80 percent of Google’s revenue comes from advertising, and the company wants an alternative to protect its business before it creates a “privacy sandbox” for cookies. turns on.
We’re still eagerly awaiting responses from around the web, but given how far Google’s proposal is still from other browser vendors, it’s not clear that privacy advocates should even make updated statements. The EFF’s FLoC statement went against: each form of user tracking, which still seems to apply to the Topics API.
†[Google’s] framing is based on a false premise that we have to choose between ‘old tracking’ and ‘new tracking’,” the EFF said of FLoC. “It’s not either-or. Rather than reinventing the tracking wheel, let’s imagine a better world without the myriad problems of targeted advertising.”
Google is targeting Q3 2023 for removing third-party cookies from Chrome, though that timeline has already been pushed back and will depend on how this trial goes. The company says it will post monthly updates at privacysandbox.com/timeline/.