The UK's CMA accepts Google's plan to phase out and replace third-party cookies with the Privacy Sandbox and will closely monitor the product's development
The UK's competition regulator will keep a ‘close eye’ on development — Google's plan to phase out third-party cookies and replace …
Context & Ripple Effects
The CMA’s position follows its investigation into whether Chrome’s cookie changes could curb rival advertising and Google’s earlier commitment to involve UK competition and privacy regulators in Privacy Sandbox’s design. By November, that process had already expanded into formal CMA oversight of the Sandbox’s development.
The acceptance turns those earlier assurances into an operating framework for Google’s cookie replacement, rather than leaving the transition solely under Google’s control.
First-order effects
- Google can proceed with Privacy Sandbox under CMA monitoring, while the CMA gains an ongoing role in reviewing how the replacement for third-party cookies is developed.
- Advertising rivals affected by Chrome’s cookie changes gain a regulator-supervised process through which competition concerns can be assessed during development.
Second-order effects
- Privacy Sandbox design choices now face scrutiny not only for privacy goals but for their effect on rival advertising businesses, raising the importance of regulator engagement in Google’s product rollout.
- Google’s commitment creates a benchmark for how the CMA can address competition risks in browser-level advertising changes through oversight rather than blocking the underlying transition.
Third-order effects
- If this oversight model persists, major platform changes to advertising infrastructure may increasingly be governed through negotiated commitments and continuous monitoring rather than one-time antitrust decisions.
The trend: Competition regulators are moving upstream into the design of platform infrastructure when product changes can reshape access to digital advertising markets.