
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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by AdExchanger // Friday, March 15th, 2019 – 12:06 am “Data-Driven Thinking” is written by members of the media community and contains fresh ideas on the digital revolution in media. Today's column is written by Preethy Vaidyanathan, chief product officer at Tapad, a part of Experian For years marketers asked, “How do we get more data?” Now that they've mastered data mining, marketers want to know what’s next. The time has come for organizations to make their abundance of digital data actionable, increase ROI and reach consumers with consistent, personalized experiences across all touchpoints. A seamless consumer experience can only be achieved by consolidating digital data. Organizations, however, are finding that consolidating data silos is more time-consuming and complicated than initially expected. The challenges One of the most pervasive obstacles companies face in when consolidating data is adopting inefficient and costly tactics that quickly become outdated. For instance, over the last couple of years, many companies turned to enterprise data warehouses to consolidate data silos, but some were too expensive or poorly suited for raw, unstructured and semi-structured data. This led companies to adopt data management initiatives, which bogged down many enterprises. Perception among senior level executives is another challenge. Many still question the need for digital transformation – achieving greater efficiencies through updating business and organizational processes with new technologies. Gartner found that more than half (54%) of senior executives say their digital business objective is transformational, while 46% say their objective is optimization. Digital transformation and data consolidation require time and effort. So, many large organizations work to overcome data silos as part of a multiyear digital transformation versus an immediate action item, delaying the benefits the company sees from taking on this project. All of these challenges make delaying progress in data consolidation easy, but companies should remember the impetus for doing so: creating a seamless customer experience that, in turn, drives business results. Brands with higher quality customer experience grow revenue faster than direct competitors with lower quality customer experience. The approach Many brands go into the digital transformation process assuming they have massive amounts of customer data, and that much of it is valuable or will be in the future. They might spend months aggregating that data in data stores or data lakes – at great expense. The trouble is that their data was scattered across multiple databases, which means it’s highly fragmented. As a result of this fragmentation, marketers can’t activate their data in ways that enhance the customer experience. To do so, companies must ensure their digital data is highly flexible so it can provide a holistic view of the consumer journey across every digital, in-store, in-venue and offline channel. I’d recommend that organizations taking on data centralization initiatives prioritize use cases that offer the company the greatest benefit. This is where organizations should establish a “crawl, walk, run” approach to data centralization to ensure key executives buy into the process. Starting with a subset of use cases, such as customer retention or upsell, or with a campaign, which is an even smaller starting point, allows executives to see the benefits of data consolidation projects relatively quickly. Once they validate these initial benefits, they can expand the range of use cases or campaigns, as well as the marketing ROI for their business. While data centralization is a long-term project that may take several years to complete, it doesn’t mean a business can’t get started now and see measurable results quickly. Break down data consolidation into stages so the organization can experience wins along the way. At the end of the day, data consolidation will help organizations deliver more effective marketing campaigns that drive business growth. Contact us today

Tapad's technology enhances Bidtellect clients frequency capping and audience extension capabilities cross device. NEW YORK, Feb. 28, 2019 /PRNewswire/ — Tapad, part of Experian, is a global marketing technology company and leader in digital identity resolution solutions, today announced a new partnership with Bidtellect (now Simpli.fi), a leading native Demand-Side Platform (DSP). Bidtellect's paid content distribution platform will leverage The Tapad Graph™ as its first cross-device partner. The integration will offer Bidtellect's clients in the U.S. and Canada cross-device frequency capping and enhanced audience extension capabilities. The combination of Tapad's leading cross-device technology, with Bidtellect's unparalleled scale and optimization capabilities, will allow content marketers within brands and agencies to develop even more strategic, effective content marketing campaigns. The Tapad Graph™ will allow content marketers to gain greater reach and create more relevant, unified messaging with targeted delivery, when used in conjunction with Bidtellect's technology. Marketers can expect to benefit from amplified reach, and enhanced, privacy-safe engagement with desired audiences as a result of this partnership. "Partnering with Tapad, the leaders in cross-device data, provides Bidtellect with a complete solution that leverages both probabilistic and deterministic mapping strategies," said Mike Conway, Chief Technology Officer at Bidtellect. "The Tapad relationship expands our audience size by providing the opportunity to reach the same user across multiple devices and, when used in conjunction with our frequency capping functionality, ensures increased reach, reduced ad saturation, and elimination of wasted ad spend." As the partnership progresses, Tapad will also work with Bidtellect to provide advanced attribution for conversions and engagement metrics including connectivity and amplification. These advanced insights will help brands and agencies develop a more holistic approach to content marketing, so they can build audiences and influence bidding algorithms that directly impact their business. "We're thrilled to be working with Bidtellect as the company's first cross-device partner," said Chris Feo, SVP of Global Data Licensing and Strategic Partnerships at Tapad. "At Tapad, we are continuously advancing our identity resolution solutions to keep pace with the ever-changing needs of marketers. As a part of that commitment, we look to work with partners where our technology is able to enhance their offering to better serve marketers. We are looking forward to creating that superior experience with the Bidtellect team." Contact us today

The Tapad Graph Now Offered in Adobe Audience Manager, part of Adobe Analytics Cloud New York, NY — August 7, 2018 — Tapad, now part of Experian, is advancing personalization for the modern marketer, announced today that its proprietary Tapad Graph is now integrated with Adobe Audience Manager, part of Adobe Analytics Cloud, helping marketers expand their view of consumers and boost results through Tapad’s probabilistic solution. Tapad has been working closely with the Adobe Audience Manager team on this integration. With the Tapad Graph integration, customers based in the U.S. and Canada can use the Tapad Device Graph to expand the reach of audiences defined and activated in Adobe Audience Manager to extend first- and third-party data and deliver personalization across paid, earned and owned channels, publisher sites, programmatic, and more. Tapad worked closely with Adobe to develop the integration, allowing marketers to enable first-party data that has been previously tied to cookies and mobile. This offering has been beta-tested by leading organizations across retail, financial services, telecom providers, and more. “We're excited to publicly announce the solution our team has been closely designing over the past 12 months with Adobe,” said Chris Feo, SVP, Global Data Licensing and Strategic Partnerships at Tapad. “This solution will give marketers in the U.S. and Canada the ability to unlock increased value from Adobe Audience Manager through the power of the Tapad Graph and its ability to expand customer prospects.” Tapad has repeatedly proven its ability to provide marketers with a unified view of the customer across channels and screens. With the Tapad Graph, a global identity graph that currently supports more than 100 enterprise customers and 200 integration partners, marketers can extend their reach and customize messages based on user and household-level data. Contact us today