We’ve always believed that there would not be a silver bullet for a cookieless world and that a multi-signal approach would be required by advertisers to navigate effectively in the future. Apple, Firefox and others have already removed 3rd Party Cookies (3PC), however we still have access to use these signals within Google Chrome, the world’s largest browser. However the elevated ‘user controls’ approach announced recently by Chrome will lead to more users rejecting 3rd Party Cookies. This means that 3rd Party Cookies can no longer be depended on as the overarching signal for targeting, measuring & optimising digital advertising across all browsers and has cemented our belief that we will be operating in a multi-signal ecosystem moving forward.
Alongside other signals, browser-based technologies will play an increasingly important role; not only for targeting cookieless audiences but also for bridging across the entire web ecosystem regardless of cookies (e.g. Measurement). Google Chrome’s Privacy Sandbox is the most comprehensive set of technologies so far, providing a range of APIs which enable use cases across and beyond advertising for a privacy-forward internet. We’ve lent heavily into understanding the Privacy Sandbox and we will focus in this article on how the industry can take advantage of the new technologies in Google Chrome to support Advertisers as we shift into the next phase of digital advertising.
As part of our readiness programme, in the first half of 2024 we ran tests across all 3 of the advertisingfocussed APIs within the Privacy Sandbox (Topics, Protected Audience & Attribution Reporting) and regularly share findings with our advertisers and ad tech partners. Our tests so far have concluded that all3 APIs functionally work broadly as we expected at this early stage, but there is still a lot more work to be done before everyone is confident in the role they can play supporting a vibrant and privacy-first openweb economy of the future.
The only way we can accelerate the development and rollout of vital solutions using the PrivacySandbox as part of a multi-signal landscape is with deeper collaboration from all sides of the industry –advertisers, agencies, ad tech, publishers, browsers & trade bodies. As we navigate through this period ourselves, we have identified three critical challenges stand out above all others in order to support advertisers interests, and should be considered in parallel with the technical feedback being provided by Capital C.
We have run functional tests across targeting and measurement use cases for advertisers but they have all been ‘proof of concepts’ or capped at low levels of investment. Primarily this is due to the limited, but increasing, adoption of updates across the ecosystem (DSPs, SSPs and publishers mostly) that are needed to use the APIs. Another factor has been the CMA testing labels Chrome agreed to apply to the1% users who have had 3P cookies removed. Separate updates are required to pass test labels and enable the privacy sandbox and we see them applied inconsistently. This reduces the % of users available to target during tests even further to a sub 1% number.
Another significant challenge to testing in H1 has been the lack of opportunities outside of the US. Many ad tech partners have chosen to initially avoid markets with more complex regulatory regulations, such as the GDPR in Europe, and focus on a single, large market which is easier to test within. Although this is not true for all solutions, especially those just using Topics signals, it is important for Advertisers to understand and validate how these globally available signals will be used across markets differently.
Breaking through this challenge requires effort from all sides of the industry. First and foremost, it is vital that the updated ad tech which enables the Privacy Sandbox is scaled rapidly across publishers and supply side ad tech partners. This needs to be incentivised and matched by buy side ad tech and partners leaning into the additional scale available, by ramping the size of test budgets and accelerating roadmaps to introduce features into their platforms for all advertisers.
To continue to support robust testing, we also want to see an updated approach to facilitating cookieless testing from Chrome which allows ad tech to test across greater proportions of Chrome users. This could be supported through the IAB Tech Lab’s Privacy Sandbox working group to streamline and accelerate scaling new solutions with a testing framework that all ad tech can align on. This would help improve consistent application of test/control audiences beyond the Chrome facilitated testing labels and reduce unpredictable auction dynamics.
There are 2 things that everyone should be aware of for the future of addressability, and they are not always obvious from the conversations we have with those who are not focussed on this topic every day.
Firstly, the Topics and Protected Audience (PA) API’s are not like-for-like replacements for cookies and we should expect some capabilities will not be replicable as privacy is enhanced. Additionally the APIs are not meant to be ready made solutions for advertisers to pick up and use; they are built for the adtech industry.
Retargeting solutions can use the PA API to build and re-engage audiences that have visited advertiser sites. This use case is fairly straightforward and has significant value for advertisers, but the testing opportunities are restricted to DSPs and rely on them making testing available.
For prospecting, both APIs can be used to develop innovative solutions with more flexible opportunities to test, as ad tech partners can develop solutions which we can deploy across any DSP. While this has driven several tests for advertisers, even where a DSP is not actively supporting the Privacy Sandbox, a lot of the solutions available in H1 have been foundational at best – often targeting topic signals directly without any additional signal or intelligence applied.
Most capital c partners with advanced solutions have started enabling cookieless, and sometimes ID-less, approaches to support the future of the open web. Some of them have been testing how the Privacy Sandbox signals could enhance their products, but many appear to have ignored them or chosen to disregard the signals completely.
We often hear that ad tech partners are instead focussing on signals which have already achieved significant scale and can be trusted to deliver results in the short term. This approach undervalues the longer term opportunity and leaves the door open for walled gardens and those with globally scaled platforms to benefit. It ignores the fact that ID-less inventory is already at a significant scale and will continue to gain share over the next few years.
Advertisers want to see more test opportunities now so they can be better prepared to reach audiences beyond IDs and are interested in bringing in new partners to test. Those who can move ahead, before the Privacy Sandbox has reached critical scale, can take the most advantage from it.
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