Google announces new interest-based tracking system for online advertising

Google has announced a new way to track users on the internet and gather data about them in order to target advertisements. The new system, called Topics API, will play a significant role in how the company targets advertisements towards users in future. Web browsers like Mozilla’s Firefox already block third-party cookies, and Google too is supposed to start doing so on Chrome from 2023 onwards. Last year, the company had said that it will move to an interest-based system of tracking instead of the current system that identifies users more closely, which is where Topics comes in.

Topics takes into account the interests of users and creates interest-based categories, such as fitness or travel. The company said that there will initially be 300 topics, which will be expanded afterwards. The users’ web browser will collect data on users for three weeks to create these topics, which will then be shared with advertisers. 

The technology giant has had trouble replacing the current system of tracking users, which privacy advocates have often criticized for being too intrusive. It had introduced FLoC, short for Federated Learning of Cohorts, which was first proposed in August 2019 as a replacement for third-party cookies, and was designed to track users and their data across websites. But that too was shunned by other browsers and privacy advocates.

At the time, the Electronic Frontier Foundation (EFF) called it “perhaps the most ambitious—and potentially the most harmful” replacement for third-party cookies and said that while it will do away with the privacy risks of third-party cookies, it could potentially create new ones in the process. FLoC used a clustering algorithm that privacy experts felt would group people based on sensitive attributes such as race, sexual orientation, or disability. It also used browser fingerprinting which could reveal a user’s identity. 

“We all agree by now that there were some serious concerns with FLoC. Google has said that under the new policy they would not be tracking sensitive information. So prima facie, it does look as if some of those concerns are addressed. But you still need to see whether the more fundamental questions around the data collection, processing and usage are being adhered to,” said Isha Suri, senior researcher at Centre for Internet and Society (CIS). 

Suri felt that a little more clarity is required on the amount and the type of information being shared with third-party advertisers. In its blog post, the company said that Topics will share three topics, one each from the past three weeks, with websites that users visit. 

This process will occur entirely on the user’s device and no data will be sent to external servers, including that of Google. The company also claimed that the topics will be transparent, and the user will have the option to delete them from their list or disable the feature altogether. Topics won’t consider sensitive interests, such as sexual orientation or race.

“Based on the information available, it appears to be a significant improvement in privacy terms over cookies, and more acceptable to privacy advocates than FloC,” said tech policy analyst Prasanto K. Roy. “Both FloC and Topics will group people, anonymizing and aggregating the data reflecting their interests. Topics is simplifying it further with a fewer number of broad topics, and leaving out topics that are sensitive like gender and race, and doing all this on your device, not on Google servers,” he added.

However, he also noted that this system may not be perfect either. “It will tell third-party trackers about what kind of sites (the broad topics, for a start) you browse, and it could potentially help websites and advertisers identify people across devices enough at least to give more targeted advertising than intended,” he added.

Google hasn’t announced when the new system will be implemented though, but a global developer trial for Topics in the Chrome browser will be conducted “soon”.

Phasing out of cookies is expected to be a huge shift for the advertising industry. Regulators in various countries are sceptical about the plan to kill cookies and have said that Google's new efforts to replace it should not impede access to user data solely for its competitors, while the company itself continues to have access to and use critical user data for its own gains. Suri pointed out that doing so could lead to a host of anti-trust issues for Google in future.

In January 2021, the UK opened an investigation into the company’s plan to kill third-party cookies as well. Of course, Google isn’t the only company taking such steps either. Apple has already implemented a system to kill third party tracking across its platforms, in a move that many said would hurt firms like Facebook that depend on targeted advertising.

Google is currently the market leader in both search and browser. According to Statcounter, Chrome with a 63.8% market share is the leading web browser across platforms. Google’s advertising business also accounts for the lion’s share of the company’s revenues, accounting for 43.2% of its total revenue during the third quarter of 2021.