Post third party cookies – where are we now?


Updated 27 January 2022:

Chrome has introduced a new Privacy Sandbox proposal to support interest-based advertising called the Topics API. This new API replaces the previous FLoC proposal and incorporates learnings that came out of the FLoC testing. This evolution from FLoC to Topics is representative of the iterative nature of the Privacy Sandbox initiative and demonstrates how Chrome incorporates feedback from the ecosystem. 

The status of this proposal is in the initial proposal stage. Testing in the browser will likely start in the coming months. We can expect Chrome to share more details before testing becomes available. In the meantime, if you want to learn more, here are several helpful resources:

Blogpost: Get to know the new Topics API for Privacy Sandbox – Topics Page

Developer  Documentation – The Topics API – (To be updated soon)

Proposal – Technical Explainer

December 2021: In February 2021, IAB Ireland hosted a zoom webinar to update our members on the preparation for the deprecation of third party cookies.  Since then, Chrome announced an extension to 2023, allowing the Industry more time to prepare for this, whilst not allowing complacency.   There has already been a lot of momentum within the industry – led by IAB Tech Lab’s Project Rearc to develop solutions that are privacy-friendly, whilst also maintaining advertisers’ ability to serve relevant advertising.  

The challenge for our industry is how to develop solutions that prioritise privacy, while at the same time do not undermine the economic viability of the ad-funded web.  We are moving towards a world where users will be anonymous by default and addressable only when they opt in.

IAB Ireland has set up a council with adtech, agency and publisher and members to consider the impact of 3rd party cookie deprecation on the Irish digital industry and solutions that our members can develop. The council created a Contextual Targeting Guide and has also contributed to IAB Europe’s Post Third Party Cookie guide.

Given that these changes are the biggest disruption to our industry since its inception, it’s no surprise that there are many companies emerging with alternative User ID solutions. Looking at the market overall, we can bucket these solutions into three categories:

● User-enabled ID solutions

● Cohorts

● Contextual solutions

It is unlikely that there will be a one-size-fits-all solution that will serve advertisers across the whole web. The future of marketing strategies will likely include solutions from all three different buckets, not just one. As we move towards this post-third-party cookie world, it is up to us as an industry to redefine what we mean by addressable.

Here are some practical steps that IAB advises our members to undertake in preparation:

Advertisers:  Assess your reliance on third party cookies and develop a testing plan for cookieless solutions. Grow your first party data, develop a clear understanding of your consumers’ content preferences to inform your contextual strategy and media activation.

Publishers:  The PTPC opportunity lies in your ability to harness first party data which will become extremely valuable to advertisers and their partners. Contextual targeting will also move centre-stage as advertisers turn to contextual targeting solutions as an alternative means to identify and communicate to more relevant audiences and interests. 

Publishers can benefit from this by investing in AI to provide and enhance the quality of the data used in contextual models to include site layout and visual attention. Positive targeting can be employed using page sentiment to target particular topics. Contextual can be a proxy for audiences in environments that have limited support for third-party cookies e.g. matching target audience profiles (where trackable) to environments that over index for a similar profile.

Agencies:  Your expertise in data and analytics will become more important than ever as advertisers rely on their agency partners to help them navigate the new post 3rd party cookie World.   Given the smaller size of the Irish market, there is great opportunity to develop close partnerships between advertisers, agencies and publishers to deliver impactful digital advertising powered by first party data and contextual targeting (harnessing the new sophisticated CT targeting models and new technologies such as AI).

IAB Ireland will continue in 2022 to bring the latest information in the form of briefings to our members and will also facilitate members working together to drive solutions that work for our market.  We hope you will continue to join us and also participate in these discussions.


  • IAB Ireland PTPC Update February 2021 – Webinar recording
  • IAB Ireland Guide to Contextual Targeting – published February 2021
  • IAB Europe’s Guide to Contextual Advertising – published July 2021
  • IAB Europe Guide to the post third party cookie era – updated July 2021
  • IAB Europe – the future of attribution in a post third party cookie era incl. Q&A with experts from the programmatic trading committee