Towards Cookie Independence

An On-the-Ground Update on Rearc

IAB Canada participates in virtually all working groups and discussions taking place around the world, that are cracking on solutions that will replace digital advertising’s dependence on third party cookies.

This complex industry problem has often been referred to as a 3D chess game and this week’s update certainly illustrates several important moves across the board. Two core groups are working concurrently to solve for both addressability, the ability to reach audiences at scale, and accountability which deals primarily in the industry’s ability to record transactions, maintain transparency and provide some sort of concrete proof of consent across bid stream activity. Both groups are critical to the future of the industry and both are meeting on a weekly basis and include literally, the smartest minds in the ad tech world.

Here’s what’s happening on-the-ground for both:


In earlier sessions, this group had been reviewing various proposals around unique identifiers as a viable replacement for cookies. The focus has recently shifted to delving deeply into “Publisher Defined Cohorts”. This method moves away from authenticated IDs towards anonymous addressability use cases. IAB Tech Lab’s working group is looking at a range of scenarios when there is no form of ID (anonymous) for buyers. This approach would require a globally standardized taxonomy to be implemented based on anonymous online behaviour clusters. For this to be viable, there must be assurances that there is in fact no persistent PI ID carried across impressions into the bid stream.

The goal would be to test this approach in real use case scenarios to get an understanding of its effectiveness as well as to identify any technical issues that might arise.

All options remain on the table in terms of viable solutions. Regardless of which direction is adopted, there will be a required non-commercial standardization of standards to create an interoperable eco-system. While there has been some pick-up on integrating early solutions that have been presented, the industry continues to present, evaluate and pressure-test alternatives.


Two recent key areas of focus for this group are centered around monitoring consented bid-streams as well as defining the data sets required to effectively account for compliance with multiple jurisdictional legal requirements.

The group is also working diligently to shape the contours of the actual monitoring mechanism. The first step towards this exercise is to focus on what is a baseline set of properties or data sets about transactions that can be passed to either a centralized or decentralized service for auditing purposes. Importantly, this mechanism is also tasked with the ability to push out regular data samples to the central/decentralized service. One of the core challenges here is the obvious need to ensure the auditing process does not become a privacy issue in of itself.

Once the industry has broad alignment on the mechanism, there will be a requirement to more closely understand the “what”. Where the core requirement is to provide supply chain integrity, we need to ensure that all actors are able to receive signals, make sure they are accurate and that vendors are able to show that they were intended to be part of a transaction. This will require actual vendor level tests and iterative work on building out machine-based anomaly detection.

Another area of great importance to this group is the development of a signing mechanism. With most of our discussions leaning towards accountability frameworks based on transparency and control signals, we need to have confidence that the signals are legitimate and untampered with. Working with the TCF and US privacy frameworks out of the gate, this mechanism will be developed to scale to other local policies as a priority.

Finally, this group is also working on beacon level use declaration to provide a better signal to inform a monitoring program. This will also need to be accessible/legible to the greater ecosystem (including browsers).

IAB Canada continues to participate and contribute to these global discussions. The activities that are taking place at this moment are perhaps the most critical towards securing the future of responsible digital advertising.

Closely related to this work, is the Canadian TCF string that is being developed to modernize privacy compliance for the industry ahead of PIPEDA amendments anticipated in the coming weeks. There has been significant progress on this front in the past week and we are heading into the technical phase of the project in the coming days. If you would like to participate in any of these important discussions, please contact us at