It’s Q1 2021 and whilst we know third party cookies are going (99.9% certain) it’s less than a year until Google deprecate them and there’s still no definite replacement.  Google’s Privacy Sandbox is one possible replacement, but many of its tools are yet to be tested & verified.  Meanwhile; there’s a host of players bringing out their own ID solutions (e.g. the Trade Desk’s UID2.0), various tests going on, and working groups formed tasked with bringing order to the various moving parts.

In this article Carbon has simplified what the possible identity scenarios are and what we’re doing to help publishers to take the fear factor out of identity.

3rd Party Cookies: Going, going, nearly gone….but not quite yet!

On Safari and Firefox third party cookies are already deprecated, with Chrome – the dominant browser globally with nearly 70% market share – to follow suit by 2022.  This has created debate & concern on identity, addressability, measurement and privacy, as well as further questions on Google’s monopolistic position in the market.

Some DMPs (Data Management Platforms) have stated that they will not be participating in the third party data ecosystem, but as an RMP (Revenue Management Platform) Carbon has taken a different approach.  Our commitment to clients is that where there is relevant and compliant third party data available that helps them achieve their goals, we will make that available to them.

What happens when 3rd party cookies disappear?

Whilst the various investigations, complaints and standards formulating may well give us more time to adapt, the change in identity is coming and Carbon will be ready whatever the scenario.  But what are the possible scenarios? The permutations are plentiful, but in an effort to simplify, here’s a summary:

Scenario 1: Little to no change

Whilst it seems unlikely that third party cookies will continue to exist beyond Google’s self imposed 2022 deadline, they could still exist at a more restricted level in terms of duration and consent.  In such circumstances we would see unified IDs and/or hashed emails increase in use to support third party cookies, especially if consent makes third party less reliable.  We would still expect a continued shift towards 1st party and increasing use of context, furthering the increases in quality audiences and demand direct deals.

Scenario 2: No third party, cross domain IDs remain compliant

A more possible scenario would see unified IDs and/or hashed emails become central to identity strategy, where vendors may be given tokens to use some third party tracking sparingly and transparently.  In this reality Chrome would need high match rates on IDs for effective targeting and would again push many towards prioritising first party and contextual, which as mentioned in scenario 1 is already the case in Safari and AMP.

Scenario 3: Cohorts live, third party dies, cross-domain IDs become less compliant

In this scenario the industry moves to solutions such as FLoC (and Google’s Privacy Sandbox) for third party alternatives.  In this reality, whilst first party and contextual become a key focus, Google would replace cookies with placing people into anonymous interest groups (something Google already does) e.g. this is 1 of 1,000 people that like cats, this is 1 of a 1,000 people that like dogs.  FLoC will be implemented in a number of ways such as Turtledove, where servers serve decisions on when to fire ads with the auctions happening on the client-side.

Questions will include who controls those servers, who controls the auctions, and who can create the cohorts?  Whilst the future of Unified IDs and hashed emails would be less certain.  In the next few months we may get some answers to these questions as the first Turtledove experiment – called Fledge – aims to implement Floc.  These tests are likely to define a number of features including the algorithm of how many people need to be part of a cohort and what is allowed.

Scenario 4: No third party tracking or cross domain solutions exist

This is a highly unlikely scenario at the opposite extreme where targeting would become 100% contextual.  No cookies at all would likely mean local storage becomes the only way to store & retrieve data (java/on-page).  In this reality all major browsers would block any attempt to track/sync/join up any data sources.

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Shaping the identity conversation

Whilst the scenarios described above give us a good indication of likely outcomes for identity going forward, the reality is that there could be a mix of these.  As a result, Carbon is working hard in a number of areas to ensure we can play in all or a mix of the possible realities.

As members of two of the larger, more established global organisations – IAB and NAI – looking after compliant consent (the prerequisite for all identity operations) we’ve always been ahead of initiatives such as TCF2.0 and GDPR, CCPA etc.  More specifically to identity though, we’re staying busy to shape the conversation.


Prebid are working in several areas in preparation for the demise of third party cookies.  Carbon Chief Data Officer, Dr Al Mclean, sits on both the Prebid ‘Privacy’ and ‘Identity Management’ committees to ensure that we can contribute & shape the conversation.

  • Firstly, in conjunction with the use of and taking ownership of UID2 Prebid are developing identity modules to give publishers fine grained control of the use of their user’s identity and first party segments.  Given the UID2 is based on authenticated logins, gaining that critical mass will be crucial but the move also creates an incentive for publishers to create high quality, trusted content to encourage user logins as the yield on high quality authenticated users will be much higher.
  • Prebid are also making an ID Import Library Module available that allows publishers to automatically tie a persistent ID (eg an email, or logon id on the page) to a map of user IDs from the User ID Module.
  • Prebid are working within the W3C to ensure that they will be able to operate as a trusted server within a finalised Fledge implementation such that sufficient information is available for Prebid to continue to function successfully. They are aware of existing flaws in the Fledge proposal and are working to have those addressed.


Carbon also have representation on The W3C Working Group for Google’s Fledge Privacy Sandbox Turtledove Proposal, and we plan to observe and participate in the upcoming origin trials and public tests in March.

Technology tests & investigations

We are also actively supporting our clients by exploring a number of id consortiums such as ID5 and Zeotap, as well as Liveramp’s email based identity solution.  In all of these tests as an RMP we will be uniquely positioned to measure the most positive impact on reach and yield.

As part of Carbon’s work within the Prebid community we are aware of other identity solutions that are currently being proposed, which we’re continuing to monitor. One is based on embedding a global anonymous ID inside the TCF Consent string. This proposed solution, which includes a transparency portal for the user, does not require any 3p cookies and is 100% independent is currently being demoed to DSPs, SSPs, CMPs and the big publishers.

Sign up here for our free webinar on the future of identity.

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