Google Delays Chrome's Cookie-blocking Changes

Google has delayed its Privacy Sandbox plan for phasing out third-party cookies in its Chrome browser until mid-2023 over a three-month period.  

Google proposed its Privacy Sandbox in 2019, with the broad goal to enable tracking of users by cohorts rather than individually to address privacy concerns about users being tracked online by marketers. It originally planned to start blocking third-party cookies in 2022. 

One of the key vehicles for enabling this new style of vague tracking of users on the web was FLoC, or Federated Learning of Cohorts, which would still allow targeted ads but would, in Google's view, improve end-user privacy. FLoC places users into interest groups. 

SEE: Network security policy (TechRepublic Premium)

Google considered it a middle ground that improved privacy but still allowed for the ad-supported web we experience today. 

Chromium-based browser makers Brave and Vivaldi objected to the first iteration of FLoC. Others have objected because Google's system could favor its own ad business. Microsoft, which has Chromium-based Edge, Bing, and LinkedIn, is not against the idea of FLoC or a similar system and advocates for an ad-supported web. 

An online privacy expert told ZDNet recently that while FLoC is an improvement on third-party cookies, FLoC does nothing to prevent browser fingerprinting, which doesn't rely on third-party cookies but still allows marketers to track users across websites. 

"Subject to our engagement with the United Kingdom's Competition and Markets Authority (CMA) and in line with the commitments we have offered, Chrome could then phase out third-party cookies over a three-month period, starting in mid-2023 and ending in late 2023," said Vinay Goel, privacy engineering director of Google Chrome, in a new blogpost.

FLoC is a type of fingerprint itself, where Google assigns a FLoC ID to clusters of Chrome users with similar interests, allowing for some privacy by letting individuals 'hide within crowds' while still enabling targeted ads for advertisers. 

Speaking about the delay, Goel said that Google needs to move at a "responsible" pace: "And by providing privacy-preserving technology, we as an industry can help ensure that cookies are not replaced with alternative forms of individual tracking, and discourage the rise of covert approaches like fingerprinting."

Goel noted that Google has wrapped up tests with Chrome users with its first implementation of FLoC. It was trialled in the US, Australia, India and other markets, but not the EU.

"We plan to conclude this origin [FLoC] trial in the coming weeks and incorporate input, before advancing to further ecosystem testing," said Goel.

"Once the development process is complete, the successful technologies are ready to be used at scale. They will be launched in Chrome and ready for scaled use across the web."

SEE: Programming languages: Rust in the Linux kernel just got a big boost from Google

Google outlined two stages for its Privacy Sandbox and FLoC. In late 2022, it will prepare the industry for the shift away from third-party cookies. 

In stage one, publishers and the advertising industry will have time to migrate their services. Google expects this stage to last for nine months, and will monitor adoption and feedback carefully before moving to stage two.

In stage two, starting in mid-2023, Google Chrome will phase out support for third-party cookies over a three-month period, finishing in late 2023.