
2024 marked a significant year. AI became integral to our workflows, commerce and retail media networks soared, and Google did not deprecate cookies. Amidst these changes, ID bridging emerged as a hot topic, raising questions around identity reliability and transparency, which necessitated industry-wide standards. We believe the latest IAB OpenRTB specifications, produced in conjunction with supply and demand-side partners, set up the advertising industry for more transparent and effective practices.
So, what exactly is ID bridging?
As signals, like third-party cookies, fade, ID bridging emerged as a way for the supply-side to offer addressability to the demand-side. ID bridging is the supply-side practice of connecting the dots between available signals, that were generated in a way that is not the expected default behavior, to understand a user’s identity and communicate it to prospective buyers. It enables the supply-side to extend user identification beyond the scope of one browser or device.

Imagine you visit a popular sports website on your laptop using Chrome. Later, you use the same device to visit the same sports website, but this time, on Safari. By using identity resolution tools, a supply-side partner can infer that both visits are likely from the same user and communicate with them as such.
ID bridging is not inherently a bad thing. However, the practice has sparked debate, as buyers want full transparency into the use of a deterministic identifier versus an inferred one. This complicates measurement and frequency capping for the demand-side. Before OpenRTB 2.6, ID bridging led to misattribution as the demand-side could not attribute ad exposures, which had been served to a bridged ID, to a conversion, which had an ID different from the ad exposure.
OpenRTB 2.6 sets us up for a more transparent future
In 2010, the IAB, along with supply and demand-side partners, formed a consortium known as the Real-Time Bidding Project for companies interested in an open protocol for the automated trading of digital media. The OpenRTB specifications they produced became that protocol, adapting with the evolution of the industry.
The latest evolution, OpenRTB 2.6, sets out standards that strive to ensure transparency in real-time bidding, mandating how the supply-side should use certain fields to more transparently provide data when inferring users’ identities.
What’s new in OpenRTB 2.6?
Here are the technical specifications for the industry to be more transparent when inferring users’ identities:
- Primary ID field: This existing field now can only contain the “buyeruid,” an identifier mutually recognized and agreed upon by both buyer and seller for a given environment. For web environments, the default is a cookie ID, while for app activity, it is a mobile advertising ID (MAID), passed directly from an application downloaded on a device. This approach ensures demand-side partners understand the ID’s source.
- Enhanced identifier (EID) field: The EID field, designated for alternative IDs, now accommodates all other IDs. The EID field now has additional parameters that provide buyers transparency into how the ID was created and sourced, which you can see in the visual below:

Using the above framework, a publisher who wants to send a cross-environment identifier that likely belongs to the same user would declare the ID as “mm=5,” while listing the potential third-party identity resolution partner under the “matcher” field, which the visual below depicts. This additional metadata gives the demand-side the insights they need to evaluate the reliability of each ID.

“These updates to OpenRTB add essential clarity about where user and device IDs come from, helping buyers see exactly how an ID was created and who put it into the bidstream. It’s a big step toward greater transparency and trust in the ecosystem. We’re excited to see companies already adopting these updates and can’t wait to see the industry fully embrace them by 2025.”
Hillary Slattery, Sr. Director, Programmatic, Product Management, IAB Tech Lab
Experian will continue supporting transparency
As authenticated signals decrease due to cookie deprecation and other consumer privacy measures, we will continue to see a rise in inferred identifiers. Experian’s industry-leading Digital Graph has long supported both authenticated and inferred identifiers, providing the ecosystem with connections that are accurate, scalable, and addressable. Experian will continue to support the industry with its identity resolution products and is supportive of the IAB’s efforts to bring transparency to the industry around the usage of identity signals.
Supply and demand-side benefits of adopting the new parameters in OpenRTB 2.6
- Partner collaboration: Clarity between what can be in the Primary ID field versus the EID field provides clear standards and transparency between buyers and sellers.
- Identity resolution: The supply side has an industry-approved way to bring in inferred IDs while the demand side can evaluate these IDs, expanding addressability.
- Reducing risk: With accurate metadata available in the EID field, demand-side partners can evaluate who is doing the match and make informed decisions on whether they want to act on that ID.
Next steps for the supply and demand-sides to consider
For supply-side and demand-side partners looking to utilize OpenRTB 2.6 to its full potential, here are some recommended steps:
For the supply-side:
- Follow IAB Specs and provide feedback: Ensure you understand and are following transparent practices. Ask questions on how to correctly implement the specifications.
- Vet identity partners: Choose partners who deliver the most trusted and accurate identifiers in the market.
- Be proactive: Have conversations with your partners to discuss how you plan to follow the latest specs, which identity partners you work with, and explain how you plan to provide additional signals to help buyers make better decisions.
We are beginning to see SSPs adopt this new protocol, including Sonobi and Yieldmo.
“The OpenRTB 2.6 specifications are a critical step forward in ensuring transparency and trust in programmatic advertising. By aligning with these standards, we empower our partners with the tools needed to navigate a cookieless future and drive measurable results.”
Michael Connolly, CEO, Sonobi
These additions to the OpenRTB protocol further imbue bidding transactions with transparency which will foster greater trust between partners. Moreover, the data now available is not only actionable, but auditable should a problem arise. Buyers can choose, or not, to trust an identifier based on the inserter, the provider and the method used to derive the ID. While debates within the IAB Tech Lab were spirited at times, they ultimately drove a collaborative process that shaped a solution designed to work effectively across the ecosystem.”
Mark McEachran, SVP of Product Management, Yieldmo
For the demand side:
- Evaluation: Use the EID metadata to assess all the IDs in the EID field, looking closely at the identity vendors’ reliability. Select partners who meet high standards of data clarity and accuracy.
- Collaboration: Establish open communication with supply-side partners and tech partners to ensure they follow the best practices in line with OpenRTB 2.6 guidelines and that there’s a shared understanding of the mutually agreed upon identifiers.
- Provide feedback: As OpenRTB 2.6 adoption grows, consistent feedback from demand-side partners will help the IAB refine these standards.
Moving forward with reliable data and data transparency
As the AdTech industry moves toward a cookieless reality, OpenRTB 2.6 signifies a substantial step toward a sustainable, transparent programmatic ecosystem. With proactive adoption by supply- and demand-side partners, the future of programmatic advertising will be driven by trust and transparency.
Experian, our partners, and our clients know the benefits of our Digital Graph and its support of both authenticated and inferred signals. We believe that if the supply-side abides by the OpenRTB 2.6 specifications and the demand-side uses and analyzes this data, the programmatic exchange will operate more fairly and deliver more reach.
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Tom Rolph, VP EMEA at Tapad, part of Experian, says that ad-sponsored streaming services can be successful if they can deliver a higher quality viewer experience than other streaming services. Last week, Hulu, the streaming service acquired by Fox and now owned 60 per cent by Disney, announced it will be regularising its ad loads. The streaming service will be bringing ad breaks down to 90 seconds in an effort to deliver a better viewer experience. This is a positive move from Hulu and one which other ad-supported streaming services should follow in order to be successful in a competitive market. Previously ad breaks on Hulu could vary wildly, from 180 seconds to 240 seconds, due to existing deals with its three owners: Disney, Comcast and AT&T. Over in the UK, we haven’t suffered from quite as inconsistent an approach as in the US, but there is still viewer frustration with the ad experience on ITV Hub and All4, where the problem tends to be over exposure of the same ad. Therefore, this move to standardise ad break lengths for streaming platforms is one that should be embraced on both sides of the pond. An important shift in this space will be to limit the number of ads during each show, but have better ad targeting to minimise repetitive advertising and increase the ROI of ad spend. All of which can be accomplished by investing in identity resolution products that can support CTV devices. Last year Ofcom found that in the UK subscriptions to Netflix, Amazon and NOW TV have risen above those to traditional pay TV services. With Netflix and Amazon both ad-free and NOW TV only a limited ad funded model, it’s clear that there is a growing appetite for ad-free viewing models. A fact that is only further supported when you consider the role of the BBC and BBC iPlayer. But the picture isn’t entirely negative for ad-funded models. There is demand for great content on ad-funded services in the UK, with ITV Hub boasting over 1bn requests and 540m hours of TV watched. The ITV Hub mobile app has also been downloaded on over 27m devices across the country – with over 22m people now registered to ITV Hub database, including more than half of Britain’s 16-24 year olds. However, to continue to attract and retain younger viewers, the experience will have to improve. There are several areas where ad-supported streaming providers need to improve in order to remain top players in this space: Ad experienceAs explored above, both volume and repetition of ads can be a turn off for viewers, but with Brits already spending a total of £303.16m every month on TV streaming services, according to Finder.com, there is potential for free, ad-funded models to flourish as people hit a limit on what they are willing to spend. There are already signs of improvement with the ad experience, with ITV just signing a deal with Amobee to allow for addressable ads on ITV Hub, while Sky’s AdSmart technology remains best in class and has now crossed over the pond to be used by Comcast stablemate NBC. Server reliabilityA cursory search finds little evidence of ongoing reliability problems with Netflix, but much evidence of problems with ITV Hub and All4, which are both prone to crashing. To compete with bigger players with massive server farms, server capacity needs to be tackled. This is especially true when it comes to live events, where many people will recall ITV Hub’s famous fails during the World Cup. While even some of the larger players have had similar streaming issues (for example, Amazon’s move into live sports streaming when they had to pull UK streaming of the US Open Tennis due to user complaints), viewing experience should be prioritised as the space gets increasingly competitive. Getting the content rightAmazon and Netflix have huge content budgets, but UK broadcasters remain strong in this regard, Channel 4 has enjoyed viewing figures of 7.5m for the Great British Bake Off, while ITV pulled in 13.7m for I’m A Celebrity. By building on UK-specific content that speaks to UK audiences, ad-supported streaming services can continue to pull in more viewers. Mobile accessMore and more Brits are choosing to watch TV content on their smartphone or tablet, according to UKOM-approved comScore data. In fact, 6.5m adults visited the BBC iPlayer app to watch video on either a smartphone or tablet, edging out Netflix which attracted 5.8m Getting the experience right on mobile, with the option to download content so it can be viewed in areas of low or no signal, is key.If UK ad-supported TV stations can crack these key areas for their Connected TV offering then they will be set up to succeed and offer a true home-grown alternative to the US streaming giants. Full article here. Contact us today

Tapad's, part of Experian, SVP of Identity shows us how marketers might communicate seamlessly through emerging channels like voice, the smart home, and, yes, podcasts.In his relatively new role as senior vice president of identity at Tapad, a part of Experian, Ajit Thupil keeps a close eye on the evolution of marketing as it becomes more intent on using data and identity technology to track ROI. Here he sits with Chris Wood at Tapad’s New York offices to discuss the future of identity. (To capture the inventive atmosphere at this location, the room they chatted in was named after Leonardo da Vinci.) For Thupil, it all comes back to the customer, whether it’s a brand client or a consumer. Brands want measurability and customers demand a seamless experience across the many devices they use in a day. While consumers are understandably reticent about giving up personally identifiable information (PII), current identity solutions use anonymous data profiles to connect the dots at the individual or household level. Given the frequency that users switch devices, along with their tendency to share bigger screens like TVs, there’s no dearth of challenges for this “head of problem solving” to solve. Contact us today

Joint solution will enhance accuracy and reach across North America, EMEA and APAC NEW YORK, April 17, 2019 /PRNewswire/ — Tapad, a global marketing technology company and leader in digital identity resolution solutions, today announced a new joint capability with Arm®Treasure DataTM , a leader in enterprise customer data management. The partnership combines The Tapad GraphTM technology with Arm Treasure Data's robust enterprise Customer Data Platform (CDP), enabling advertisers in the Arm Treasure Data marketplace to access Tapad's datasets. With the integration of Tapad's Graph and Arm Treasure Data's existing first party data, marketers will be able to deliver scalable, cross-device messaging with precision. In addition, marketers can benefit from anonymous customer journey analysis, audience expansion and online and offline attribution. Arm Treasure Data's APAC market customers will have access to expanded audience reach by leveraging Tapad's global, proprietary datasets. While Tapad will be able to extend its presence into the APAC region, tapping into Arm Treasure Data's existing footprint. "Combining Tapad's Graph with Arm Treasure Data's CDP will enable our customers to make holistic, data-driven decisions that increase ROI," said Chris Feo, SVP of Global Data Licensing and Strategic Partnerships at Tapad. "In combining these two solutions, we can now offer advertisers the value of both technologies to optimize their marketing initiatives and create seamless experiences across multiple devices and channels." "The Tapad GraphTM is a trusted and established platform with a history of innovation," said Stephen Lee, Senior Director, Business Development, Arm Treasure Data. "Integrating Tapad's technology into the Arm Treasure Data CDP will allow for streamlined experiences across markets, achieving global scalable reach." For more information about The Tapad GraphTM, or to request a demo, visit our identity page. About Tapad Tapad, Inc. is a global marketing technology company and leader in digital identity resolution solutions. The Tapad GraphTM, and related solutions, provide a privacy-safe approach to connecting device identifiers to brand and marketer data, thereby allowing for enhanced measurement, attribution, reach and ROI of marketing campaigns. The Tapad GraphTM enables marketers around the world to maximize campaign effectiveness and drive business results. Tapad is recognized across the industry for its innovation, growth and workplace culture, and has earned numerous awards, including the TMCnet Tech Culture Award. Based in New York, Tapad also has offices in Chicago, London, Oslo, Singapore and Tokyo, and is a wholly owned subsidiary of Telenor Group. About Treasure Data Arm Treasure Data enterprise Customer Data Platform (CDP) unifies data from multiple sources – online, offline, IoT and device generated data – and empowers enterprises to disrupt their markets with superior customer experiences. Our customers are creating transformational customer relationships by connecting the data dots with our CDP. Arm Treasure Data is fully owned by Arm Holdings and has a global customer base of over 300 enterprises including Fortune 500 and Global 2000 companies. Our clients manage over 130 trillion records, resulting in more predictable and profitable business results. Contact us today