As of February 16, 2025, Google will sanction advertisers to use digital fingerprinting, a data collection technique that gathers information about a particular device, browser, or user.

• Google avoided the term “fingerprinting” in its official announcements, but said it would be “less prescriptive with partners in how they target and measure ads” as privacy-enhancing technologies (PETs) unlock “new ways for brands to manage and activate their data safely and securely.”
• Reading between the lines, the UK’s Information Commissioner’s Office (ICO) released a statement opposing the changes, noting, “Businesses do not have free rein to use fingerprinting as they please. Like all advertising technology, it must be lawfully and transparently deployed—and if it is not, the ICO will act.”

Why it matters: Access to users’ IP addresses or device information helps advertisers track behavior across devices.

• “Cross-device measurement is critical, especially on connected TV (CTV), where attributing impressions to sales is difficult because conversions usually occur on a desktop or mobile device,” said our analyst Evelyn Mitchell-Wolf.
• A third of US agency/marketing professionals use cross-device measurement to mitigate measurement issues, according to data from the Interactive Advertising Bureau (IAB), Advertiser Perceptions, and Guideline.

Making a U-turn: This decision is a pivot for Google, which in 2019 claimed fingerprinting “subverts user choice and is wrong,” per the ICO.

• “Google is changing a policy that it once stood behind pretty adamantly,” said Mitchell-Wolf. “But fingerprinting is very common and it’s hard to police.”
• Because digital fingerprinting is such a widespread practice, it’s difficult for any organization to monitor and enforce restriction.
• Instead, Google has decided to invest in PETs that make data collection safer.

But so far, Google has provided few specifics about how these PETs will protect user privacy.

“Google has been very vague about where PETs will be employed as it processes consumer data. Whether advertisers themselves will need to change anything about their data collection practices remains to be seen,” said Mitchell-Wolf.

The bottom line: As long as they’re compliant with applicable privacy laws, advertisers can stay the course on their targeting and measurement strategies for the time being.

However, Google giving consumers the choice to opt out of third-party cookie tracking, along with its plans to deprecate its mobile ad ID, will still contribute to signal loss, requiring advertisers to prepare for a more challenging measurement landscape ahead.

This was originally featured in the EMARKETER Daily newsletter. For more marketing insights, statistics, and trends, subscribe here.