
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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The partnership between Experian and Fusion92 exemplifies how collaboration can deliver real marketing impact. This article explores the ways Fusion92 relies on Experian’s data to sharpen its audience targeting, streamline engagement across channels, and achieve measurable success. A need for unified audiences When Fusion92 set out to advance how their clients connect with precise audiences, they needed a data partner that could deliver comprehensive and actionable insights. Enter Experian. By using Experian’s marketing data and digital identity graph as a core source of data, Fusion92 built a solid foundation for their tools, DIOS (Data Input Output Solution), DAX (Data Advertising Exchange), and NoMi (pronounced “Know Me”). These powerful technologies enable Fusion92’s clients to control audiences more precisely, connect with the right people across optimal channels, avoid wasted impressions, and measure results with confidence. Why Fusion92 chose Experian Quality and reliability Experian’s commitment to data accuracy has earned the #1 ranking from Truthset, ensuring Fusion92’s campaigns are built on precise, actionable, and privacy compliant data that businesses can trust. Breadth and depth By offering demographic, behavioral, and channel preference data, Experian enables Fusion92 to have greater control over precision activation, empowering better results. Expert support Experian works closely with Fusion92 to provide tailored solutions and dependable expertise, adapting to meet the unique needs of their diverse clients. “Experian never really let me down in terms of data quality, data accuracy, and data reliability.”Dave Nugent, EVP of Data Science & Strategy, Fusion92 The power of teaming up Challenge A regional amusement park needed to increase membership renewal sales during peak season while reducing spend on households unlikely to visit. Solution Fusion92 combined the park’s first-party buyer file with Experian consumer data and custom geographic boundaries, built an advanced targeting model, and used Experian’s channel-preference insights to prioritize the media mix. The unified audience was then delivered omnichannel through Fusion92’s in-house proprietary DAX activation technology, with Experian’s identity graph supporting attribution. Result The marketing conversions beat the park’s stretch goal by 70%, confirming that accurate data and coordinated activation drive revenue lift. “It doesn’t matter if you’re a beginner or an expert. Experian will help you make the best use out of an incredible set of data assets.”Dave Nugent, EVP of Data Science & Strategy, Fusion92 Using marketing data to power omnichannel marketing Tools built by Fusion92 that meet client needs Fusion92’s suite of tools handles every essential phase of a campaign. DIOS starts by creating audience definitions and setting a foundation for strategy. Once these insights are established, DAX takes over, activating consistent, controlled engagement with tailored messaging. Detailed performance metrics throughout help optimize strategy along the way, ensuring campaigns remain impactful and cost efficient. DIOS in action DIOS eliminates guesswork, combining Experian’s data with advanced analytics to create precise audience models. This capability enables Fusion92 to define customer segments with accuracy, providing businesses with a roadmap to success from the outset. While currently in use as a managed service by Fusion92, a public-facing SaaS version is expected to be released in 2025. Activating every channel through DAX The campaign execution phase is pivotal, and DAX ensures smooth delivery and transparent measurement across channels. By incorporating Experian’s identity graph, DAX provides a clear picture of cross-channel behaviors and preferences, and how they impact business goals. This holistic approach enhances personalization, connecting online and offline interactions to create campaigns that resonate with consumers and drive ROI. Getting to know NoMi NoMi offers next-generation audience intelligence, empowering businesses with audience profiles built from behavioral insights, like transactional activity or in-market signals. This ensures that campaigns connect with people authentically and at scale. With NoMi, Fusion92 clients streamline targeting efforts, improving efficiency while reducing wasted spend. Thinking about your own transformation? Whether you’re tackling siloed activation, enhancing attribution models, or aiming for improved targeting, Experian’s data solutions can help amplify your efforts – just ask Fusion92. Explore how we can help you target smarter, engage better, and measure success confidently. Connect with an Experian representative today About our experts Dave Nugent, EVP of Data Science & Strategy, Fusion92 Dave Nugent, EVP of Data Science & Strategy at Fusion92, has over 27 years of experience in data-driven services, helping organizations better understand and target their audiences through predictive modeling and segmentation. Before joining Fusion92, he spent 11 years at American Spirit Corporation as VP of Data Solutions and co-founded Market Reason, where he secured a patent for an identity technology known as \”identity solutions.\” Dave’s expertise bridges traditional, digital, and social advertising, offering innovative approaches to data utilization. He also shares his knowledge as a guest lecturer at the University of Chicago Booth School of Business. Crystal Jacques, VP of Enterprise Partnerships, Experian Crystal Jacques is the VP of Enterprise Partnerships, leading Experian\’s go-to-market team across all verticals. With over ten years of experience in the Identity space, Crystal brings a wealth of expertise to her role. She joined Experian in 2020 through the Tapad acquisition, following her successful stint as the head of Global Channel Partnerships for Adbrain, which The Trade Desk later acquired.

Audio platforms that overcome consumer identity challenges are winning new advertisers and driving higher ROAS. In this article, you’ll hear from leading audio platforms that are solving these challenges—and seeing results. Digital audio is evolving fast. What was once a niche channel of host-read sponsorships and direct buys is now a must-have in the modern media mix. Streaming platforms, podcasts, and digital radio are drawing more ad dollars thanks to audio’s ability to capture attention and connect with listeners. But with growth comes new pressure. Advertisers expect accuracy, scale, and to see results. At the same time, listeners want more relevant content and more personalized ad experiences. That’s where identity becomes essential. With Experian’s identity and audience solutions, audio platforms can: Bolster addressable audience targeting and personalization capabilities. Gain a comprehensive view of listeners’ digital identity to reach audiences across channels. Better understand consumer preferences, enabling advertisers to reach audiences with greater accuracy. Enhance the listening experience with more relevant content. Let’s break down the key challenges in audio—and how Experian can help solve them. Challenge 1: Anonymous listening limits addressability Most listening happens in environments where people aren’t logged in—via apps, smart speakers, and mobile devices. Without logged-in data, platforms struggle to know who’s listening and advertisers are unable to reach those anonymous listeners who don’t have an addressable ID. To overcome the identity gap in unauthenticated listening environments, leading audio platforms are turning to partners that connect fragmented signals—like device type, location, and behavioral patterns—to broader household and individual profiles. By using hashed emails and other alternative identifiers, platforms can begin to make anonymous sessions more addressable. This increase in addressability ensures the platform’s entire userbase can be reached, which leads to an increase in revenue. Experian’s solution Experian\’s identity spine, comprised of our Digital and Offline Graphs, helps you recognize listeners even when they’re outside your ecosystem. Platforms like Audacy are already leading the way. By integrating Experian’s Digital Graph, they’re gaining a more complete view of listeners’ digital identifiers—enhancing the experience across their app and website. With a better audience understanding, Audacy can deliver personalized content while helping advertisers reach specific groups with greater accuracy. Challenge 2: IP-based targeting falls short Audio has traditionally relied on IP addresses, but that’s no longer enough. A single IP could represent an entire household—or a public setting like a coffee shop. It’s not precise. Forward-thinking platforms are moving beyond IP-based targeting by integrating identity resolution technologies that combine household-level data with device-level intelligence. These solutions help distinguish between shared devices and individual listeners, allowing advertisers to serve more relevant messages without over-reliance on a single signal like an IP address. This layered approach improves precision—especially in dynamic listening environments like vehicles or communal spaces. Experian’s solution Our identity spine links home IPs to households, then connects them to specific devices and individuals. This helps platforms move beyond basic IPs and target real people based on accurate signals—even in shared listening environments like smart speakers and cars. We also help platforms and advertisers integrate alternative IDs—like Unified I.D. 2.0 (UID2)—into their programmatic audio campaigns. That means more reach, without compromising consumer trust. Challenge 3: Audio buying is fragmented From podcasts to streaming to radio, audio lacks consistency in how inventory is packaged and bought. It’s hard for advertisers to run scaled campaigns across channels—and harder still to measure performance. Plus, advertisers don’t think in silos—they think in strategies. If audio can’t connect to their display, connected TV (CTV), and social buys, it loses ground. What they need is a way to define audiences once and activate everywhere. To reduce friction in audio ad buying, platforms are investing in infrastructure that unifies audience insights across formats. By building a centralized view of the listener—regardless of whether they\’re tuning in via podcast, stream, or radio—publishers can offer advertisers consistent targeting parameters, clearer reporting, and better campaign orchestration. Identity graphs and audiences are playing a growing role in streamlining this complexity and unlocking scale. Experian’s solution Experian helps simplify audio buying. Experian audiences are built on top of our identity graph and are expanded to a deep set of digital identifiers, ensuring accuracy, scale and maximum addressability across channels. Platforms can blend their first-party data with advertiser data and our audiences—then deploy those audiences onsite or activate programmatically across open web and CTV. DAX is doing just that. DAX\’s partnership with Experian combines Experian’s 2,400+ audiences for targeting and activation with DAX’s innovative audio advertising approach. We’re helping advertisers connect with passionate and engaged listeners nationwide. \”Through our partnership with Experian Marketing Services, advertisers can unlock deeper audience insights and execute more impactful digital audio campaigns. By combining our shared market presence, knowledge, and forward-thinking approach, we’re strengthening our digital audio network offering and delivering value to all our advertising partners.\” Brian Conlan, President of DAX United States In addition to integrating Experian’s Digital Graph, Audacy is also integrating Experian\’s syndicated audiences to unlock accurate insights like demographics, shopping behavior, and interests – providing listeners with a more personalized advertising experience and advertisers with a higher return on investment. “Historically, audio advertising lacked precise targeting capabilities, making it challenging for advertisers to reach specific audiences. By integrating our digital identity graph and syndicated audiences with Audacy’s platform, we’re transforming how advertisers connect with listeners. This collaboration enables more effective audience targeting and delivers personalized, impactful audio experiences across all channels.”Chris Feo, Chief Business Officer, Experian Privacy is non-negotiable Everything we do is privacy-forward by design. Backed by Experian’s Global Data Principles and decades as a regulated institution, we rigorously vet every data source to ensure compliance with all federal and state laws. Build an audio strategy that performs with Experian Your advertisers want more from their audio investments. With Experian, you can give it to them. We help you: Expand digital addressability to maximize reach for marketers and drive revenue growth for your platform. Create and activate addressable audiences across all channels. Enhance the listening experience with relevant content and personalized ads. Audio has always been a powerful way to connect. Now, it’s ready to perform. Let\’s connect Latest posts

When we launched our data marketplace earlier this year, we set out to transform how the industry discovers and activates privacy-safe audiences and maintains addressability across display, mobile, and connected TV (CTV). Yieldmo was one of the first adopters and their story speaks volumes about what’s possible when flexible tech meets premium data. Large retail brand boosts in-store traffic with Yieldmo and Experian Yieldmo, an advertising platform known for its inventive, AI-powered creative formats and privacy-first inventory, partnered with Experian to support a leading athletic retailer’s campaign focused on driving in-store traffic. The goal? Attract in-store shoppers likely to purchase from competitors, particularly during key sales windows. Using Experian’s Audience Engine platform, which includes our proprietary and third-party data marketplace, Yieldmo built a high-performing, self-serve targeting strategy that included both conquesting and in-store shopper segments. With the ability to easily combine Experian Audiences and Partner Audiences, like those from Alliant, Circana, Webbula, and Sports Innovation Lab, Yieldmo quickly built precise apparel and footwear audiences. Using Experian’s identity graphs in Audience Engine, Yieldmo increased cross-channel addressability to maximize campaign scale and impact. “Experian’s data marketplace in Audience Engine fills a critical gap, letting us quickly search by brand, build smarter conquest segments, and activate custom audiences fast. The platform is flexible and the support is hands-on and reliable.”Abby Littlejohn, Director of Sales Planning at Yieldmo With self-serve setup that cut down manual work, the ability to build highly tailored audiences, and expected lift in store visits, Experian helped the team achieve standout results. \”We selected Experian as our primary third-party data partner based on contract ease, audience quality, and speed. Through Experian, we can find high-performing audiences from multiple providers that meet our client’s targeting objectives. We include Experian audience segments in 80% of formal RFP proposals and are in active discussions on how to optimize for future campaigns—making Experian a go-to partner for third-party targeting.”Nelson Montouchet, AVP, Strategic Partnerships, Yieldmo More data, more reach: Experian’s data marketplace fuels smarter targeting across ad platforms Today, just months after launch, Experian’s data marketplace is gaining traction across the ecosystem. Over 10 platforms, including leading supply-side platforms (SSPs) and TV platforms such as Madhive, OpenAP, and Optimum, are now actively utilizing our data marketplace to enhance their activation capabilities. As privacy rules tighten and many identity signals start to fade, a lot of activation platforms are finding it tougher to reach their audiences. This is where our data marketplace shines, with one of the most comprehensive identity graphs out there, 126 million households, 250 million individuals, and over four billion active digital IDs, we make it easy to activate audiences while keeping addressability high across channels. We preserve accuracy when scaling to digital IDs via our identity graphs since Experian is rooted in offline data, which provides better connections and smarter targeting. “Our long-standing partnership with Experian and breadth of Experian\’s data marketplace, combined with the interoperable, direct matching methodology of our Open Identity solution, make it possible for OpenAP to enable advertisers and agencies to use best-in-class data partners to build audiences with the highest fidelity and consistently reach audiences at scale wherever they are consuming content across premium video.”Chris LoRusso, Chief Business Officer at OpenAP Experian’s data marketplace has grown to include over 20 premium data providers, such as: “We’re thrilled to bring PlaceIQ’s privacy-first, visit-based audiences to Experian’s marketplace, giving brands quick and easy access to high-intent shoppers. From recent big-box customers to yoga-studio regulars, advertisers can add real-world relevance to campaigns across every channel.”Brian Bradtke, Head of Partner Development, Precisely PlaceIQ These partnerships bring unique value to platforms looking to understand and engage audiences more effectively, whether through physical location intelligence, sports and fandom insights, or behavioral intent signals. What’s next As we head into one of the industry’s key events this summer at Cannes, the excitement around our data marketplace continues to build. We\’re focused on expanding our data ecosystem and helping platforms and marketers turn fragmented data strategies into a unified competitive advantage. If Yieldmo’s story is any indication, this is just the beginning. Let’s connect and explore how Experian’s data marketplace can help you drive more revenue, scale your audience reach, and stay ahead of privacy shifts. Connect with us Latest posts