Google Privacy Sandbox update: Chrome is retiring several APIs (and doubling down on interoperable attribution)

Original post (source): Privacy Sandbox (Google) - “Update on Plans for Privacy Sandbox Technologies” (Oct 17, 2025)

• https://privacysandbox.google.com/blog/update-on-plans-for-privacy-sandbox-technologies

The headline

Google is keeping its current approach to third-party cookie choice in Chrome, and is updating its focus for Privacy Sandbox.

The practical takeaway for app marketers: measurement and privacy plumbing is still moving, and the “stable set of APIs you build around” can change faster than your attribution model deck.

What Google says it will focus on

Three themes called out in the update:

• Scaled measurement: continuing to engage on an interoperable Attribution standard via the web standards process.
• Privacy + identity flows: continued support for CHIPS and FedCM.
• Fraud and abuse: continued support for Private State Tokens and exploration of more approaches.

What’s being retired (important for planning, even if you’re not deep in the weeds)

Google says it will retire several technologies due to low adoption, including:

• Attribution Reporting API (Chrome and Android)
• Protected Audience / Protected App Signals
• Topics
• Private Aggregation / Shared Storage
• and several others listed in the post

My editorial take

If you run app growth across web + app (or you’re planning to), this is a reminder to:

• separate what’s true (incrementality goals, north-star events) from what’s implementation detail (the specific API du jour)
• keep a small “measurement risk register” so changes don’t show up as surprise gaps in reporting

Tiny win: write down the 3–5 data dependencies your reporting assumes (cookies, device IDs, SKAN, server-to-server events, MMP links), and mark which ones are policy-controlled vs. under your control.

Read the original: https://privacysandbox.google.com/blog/update-on-plans-for-privacy-sandbox-technologies