• by Wendy Davis  @wendyndavis, October 23, 2023

Google is readying a privacy initiative aimed at hindering “device fingerprinting” -- a controversial tracking technology that recognizes users based on their computers' characteristics.

The planned feature, IP Protection (previously called Gnatcatcher), involves masking IP addresses from domains used by third parties -- including Google-owned domains like doubleclick.com and admob.com.

"IP Protection is a feature that sends third-party traffic for a set of domains through proxies for the purpose of protecting the user by masking their IP address from those domains,” Google software engineer Brianna Goldstein wrote Friday in a summary of the project. The plans were first reported by Bleeping Computer.

IP addresses are among the datapoints that some ad tech companies rely on for fingerprinting.

Privacy advocates have long voiced concerns about digital fingerprinting. The standards group World Wide Web Consortium warned in 2015 that digital fingerprinting -- along with other forms of tracking that are difficult for users to control -- was "a blatant violation of the human right to privacy.”

Google says it plan to only hide addresses from domains on a list of known trackers.

“We are conscious that these proposals may cause undesired disruptions for legitimate use cases and so we are just focused on the scripts and domains that are considered to be tracking users,” Goldstein wrote.

She added the feature will launch on an opt-in basis in order to “help ensure that there is user control over privacy decisions and that Google can monitor behaviors at lower volumes.”

Other browser developers including Apple and Mozilla have also taken aim at device fingerprinting.

Since 2021, Apple's Safari browser has masked IP addresses from known trackers by default.

Mozilla's Firefox also takes steps to prevent ad-tech companies from tracking users based on their devices' characteristics.