European Universal ID Tracker

By: Joe Cha

Welcome to your weekly update on the state of all things European Universal ID – aka: universal IDs, salted hashed email tokens and more – in the European bidstream.


You’ve been asking us to share European Universal ID insights to help make decisions about your identity infrastructure today and in the future, so that’s exactly what you’ll get in this tracker.

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November 18, 2022 release

➜ Graph A: European Universal IDs  observed in the bidstream  |  June – October 2022

* We removed this data from the report because we can’t get a precise number of how many people are represented by ID5 IDs listed in the bidstream (due to the encrypting strategy). We plan to add ID5 back in a future update when we look at the number of bid requests per identifier that we see in a given time period.


Roqad has a front row seat to the European Universal ID  landscape (among others), and while we can’t speak for every single bid transaction, we have a pretty good view of what is happening.


We’ll be posting updates on a weekly basis, so don’t forget to sign up for post alerts above.

Graph A shows extended IDs (also called universal IDs, also called hashed email tokens) from June to October, 2022 across the European market.

We’ll get into the deterministic data points that these identifiers are tied to shortly.

The most prominent identifiers by volume are: (TheTrade Desk) – 1.1 B – 870 M (Prebid) – 626 M – 67 M

Note that we don’t have a horse in the race so to speak, we don’t have a favorite or even a preferred identifier. We basically just collect and connect them via an identity graph.

This makes us a great resource for these trends. A source of truth. No bias.

Most of the identifiers come from DSPs. Scroll down for the full list.

Obviously the extended IDs (aka universal IDs aka hashed email tokens) are trending up and to the right, an average increase of 23% among the top five.


Before we get into our explanations, take a look at Graph B. Here are the types of deterministic data to which the above identifiers are tied.


➜ Graph B: Types of deterministic data tied to extended IDs observed in the European bidstream  |  June – October 2022

Graph B: types of deterministic data tied to extended IDs observed in the EU bidstream / Jun. to Oct. 2022


Observations and pontifications

  • Extended IDs (also called Universal IDs or Hashed Email tokens) are trending up and to the right, averaging a 23% increase. We expect the trend to continue.
  • Obviously the deterministic data set is dominated by third-party cookies.
  • Note that a Publisher can set 20 third-party cookies per page/per user if they like, and we would see them all in the bidstream.
  • Mobile advertising identifiers are limited to one at a time.
  • There are more publishers using Prebid ( right now. Prebid allows publishers to use more than one identifier on the same page at the same time.
  • Why use several different IDs at once? Big publishers are probably covering their bets to make sure their inventory is being used.
  • The so-called third-party cookie apocalypse didn’t happen, it’s postponed until 2023, perhaps longer, so identity providers are using third-party cookies and syncs extensively as long as they’re available.
  • Yes, third-party cookies are being used to prepare for the cookie apocalypse.
  • All of these identity providers are using third-party cookies as a crutch to get their ID out there before they’re deprecated in Google Chrome.
  • No one knows who will win the identifier competition. Right now it makes sense to work with several at a time just in case.
  • It appears that the publisher ID problem in mobile is not being solved with a single or small group of universal IDs.

There are three main buckets of identifiers:

#1 – Bucket A: Partner and time stamp encrypted, which is helpful for capturing revenue for the provider. They’re designed to make the advertiser pay [and why not, money makes the world go ‘round.]

#2 – Bucket B: Partner specific encryption. Think UID 2.0 in the US (not yet available in the EU), and NetID in Germany. The design is focused on user privacy protection.

#3 – Bucket C: Unencrypted IDs. Think Lotame’s Panorama or Criteo. Why do they offer an unencrypted ID? In Criteo’s case, they want to use it themselves! They don’t care if others use it. They want to bid on ads and they do a lot of it. The other reason for an unencrypted ID is that the provider wants to give the internet a transactable currency. If you leave it unencrypted, then maybe it’ll drive usage.

The full list of identifiers observed in the European bidstream:



Now you have a front-row seat to the tracker and we’ll keep an eye on these trends week to week. I think we can all agree that it will be interesting to revisit a few months from now to see how the tides are turning.

We expect to see more techniques that are preparation for the big cookie apocalypse, similar to what we’re seeing with and publishers using multiple identifiers per page.
Accordingly, we expect to see some movement in data volumes amongst the identifier providers. The top 5 by volume probably won’t change in the near term, but the next 10 could see some movement.


If you’re ready to have a conversation about including Roqad’s graph in your identity spine, give us a shout.

December 6, 2022 update

You’ve already seen the June to October 2022 launch data. Now, we’re breaking things down by week, going back to week 41, which is October 9 to 16 (Sunday to Sunday), and through week 47, which is November 20 to 26.


Graph C: Extended IDs observed in the Europe – Week # 41-47, 2022. The top three IDs by volume.

graph c wks 41-47, 2022 universal id tracker for eu(1)


Graph C shows extended IDs (also called universal IDs, also called hashed email tokens) from October through most of November, 2022 across the European market.

The three most prominent identifiers by volume are: (TheTrade Desk) –  1.8 B – 1.3 B (Prebid) – 995 M

Notes on Graph C

  • The top three are the same companies that we saw in the previous November 18 post (see above). It will be interesting to check in with the volumes after the holiday shopping season.
  • The ID5 ID actually ranks pretty high in volumes, but we do not have an accurate count at this time because of their encryption set-up. The exact same ID can appear several times in a different form but we cannot tell since we do not have the “key” to unlock it. So, we are leaving it out of the graph at this time. See above for a longer explanation.
  • ranks high in volume because of their feature of allowing multiple IDs on a single web page. Publishers can use multiple IDs to hedge their bets as there is no one ID that (at this time) “rules them all.” Next year should be an interesting one for the ID race. See above for a longer explanation.
  • Overall, the extended IDs (aka universal IDs aka hashed email tokens) are trending up and to the right. Why? See above for a longer explanation.

Now take a look at Graph D. We didn’t show this view in our launch data – here we see the NEXT four IDs by volume. It was awkward to put them all in one graph as there is a big drop off between number three and number four.

Graph D: Extended IDs observed in Europe – Week # 41-47,  2022. The NEXT four.

graph d. THE NEXT Four IDs by volume

The “next” five: – 112 M – 22 M
identityLink – 20 M – 17 M
pubcommon – 12 M

Notes on Graph D

  • identityLink is operated by LiveRamp.
  • Re: the “Britepool” ID. Britepool merged with in 2021. Apparently they kept the original Britepool ID name. BigToken actually has an interesting product concept. From their website: You can use the BIGtoken application to manage your digital data and identity and earn rewards when your data is purchased. Third-party applications and sites access BIGtoken to learn more about their consumers and earn revenue from data sales made through their platforms.
  • I asked our VP of Sales, Alasdair Cross, for his impressions of Graph C and D. He said, “It’s surprising how quickly NetID has grown, increasing over 300% in the last 2 weeks. It looks like the publisher consortium of, RTL, ProsiebenSat, 1and1 and others are rapidly pushing the ID out to their customers.”

As always, if you’re ready to explore an id-agnostic solution for your identity spine, contact us. We’ll be back with more next week.










About The Author
Joe Cha

Joe Cha is a marketing director with Roqad.

He has created content marketing projects for machine learning / artificial intelligence companies for the last 3 years. He previously served as content lead for fraud prevention ML company Nethone, which raised Series A and was named one of the fastest-growing companies in Central Europe by Deloitte.   

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