Google Ads would like to request increasing the cap of interest groups per owner to 2000.

We believe a minimum of 2000 will enable advertisers to find more success with the Protected Audience API, improve adoption and competitive parity with 3P solutions, without sacrificing any meaningful privacy-preserving benefits.

Under the current proposal, there will be a guardrail of 1000 interest groups per owner. Today, advertisers have no cap on the number of ULs and a non trivial number of users exceeds the 1000 cap.

Reasons for this change:

• Valuing a range of advertiser needs: we believe a more restrictive cap is ignoring the needs for a wide range of advertisers as advertisers with a rich and diverse SKU set may require the ability to create numerous, niche groups.
• At the same time constraints such as Interest Group expiration and k-anonymity will automatically ensure that each ad-tech streamlines the number of IGs each ad-tech stores and maintains over time.