
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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It’s been one week since the highly anticipated Cannes Lions 2024—the event of the year for advertising and creativity. We are excited to present our top five takeaways from the event, revealing the industry's priorities for the year ahead. Navigating the post-cookie era One of the pivotal discussions at Cannes Lions 2024 centered around signal loss and identity resolution. The industry is grappling with the impact of third-party cookie deprecation, driving a move toward alternative identifiers such as Unified I.D. 2.0 (UID2) and ID5, and contextual targeting. This shift aims to uphold accurate audience targeting while addressing privacy concerns through authenticated forms of identity. Brands and agencies are actively exploring these new strategies to replace traditional cookie-based methods with stable, privacy-compliant solutions. First-party data providers are also seeking data onboarding solutions to navigate this transition. They need streamlined integration processes, comprehensive ID-matching capabilities, and transparent pricing structures. Fortified by our roots in offline data and significant investments in our Graph, and our newest offering, Third-Party Onboarding, you can count on Experian's solutions to maintain strong signal coverage in a cookieless world so you can have uninterrupted, effective marketing. Unifying targeting across TV platforms Another focal point at Cannes Lions 2024 was the challenge of navigating TV fragmentation. Advertisers strive for unified targeting across diverse TV platforms, including connected TV (CTV) and traditional linear TV. They emphasize integrating data sources and ad servers to reach audiences across these platforms. CTV continues to stand out in conversations as a crucial and expanding area for advertising, offering new opportunities for targeted campaigns and broader audience engagement. We're fueling the expansion of CTV advertising through our signal-agnostic Graph, which seamlessly integrates CTV IDs, universal identifiers such as UID2, IP addresses, and mobile ad IDs (MAIDs) for targeted campaigns. Our newest offering, Third-Party Onboarding, also provides connectivity to more than 10 TV destinations. Transforming marketing with AI We would be remiss not to mention the hottest topic at Cannes Lions 2024, the transformative power of AI within data and identity. Discussions highlighted AI's pivotal role in revolutionizing marketing strategies by enhancing campaign planning, dynamic optimization, measurement, and analytics. AI is not just a tool; it enables marketers to work smarter and faster. With real-time data enrichment, AI will empower marketers to manage large-scale campaigns with unprecedented efficiency and precision. Marketers envision a future where AI seamlessly integrates into every aspect of their strategy, from understanding and predicting consumer behavior to automating personalized engagement. They see AI as the key to unlocking new levels of precision and efficiency, allowing them to adjust real-time campaigns based on consumer interactions and preferences. This vision includes using AI for deeper audience insights, ensuring that every marketing touchpoint is relevant and impactful. Striving for strategies for proven ROI Discussions on measurement at Cannes Lions 2024 focused on how measurement metrics are evolving to keep pace with industry changes. Cross-device, multi-touch attribution, and outcome-based metrics like consumer lifetime value and conversion rates are becoming more important. Accurate measurement is critical for demonstrating campaign impact and optimizing future marketing efforts. These developments reflect a shift toward more sophisticated measurement practices to optimize marketing strategies and prove tangible ROI. Through our Consumer Sync solutions, you can improve your attribution quality to understand the true path to conversion by linking all digital touchpoints to a single person. Creating integrated consumer experiences with retail media networks Retail media networks (RMNs) are becoming more integrated and connected. Their goal is to provide consumers with a unified online and physical store experience and create a comprehensive marketplace where retailers can work together and use shared data to better reach and engage with their audiences. "Throughout the conversations, it's been clear that there's a lot of demand and interest in building and growing retail media networks. What strikes me is that Experian products, both across identity and data, can be a big support to help grow and fill in these gaps."budi tanzi, vp, product Discussions at Cannes Lions 2024 emphasized how collaborations with technology providers and industry groups can help set measurement standards and ensure transparency. These partnerships can enable RMNs to expand their reach and compete with larger advertising platforms, driving industry growth and innovation. Experian offers comprehensive solutions for RMNs. Our Profile Insights and Enrichment tools offer valuable customer behavior insights, driving smarter inventory management. We enhance ad targeting beyond item-level purchases with accurate data and syndicated audiences, aligning with broader media strategies. Third-Party Onboarding enables expansion beyond owned and operated inventory, supported by our Graph for enhanced connectivity. "Data providers are excited to eliminate digital hops in their data flow using Experian Third-Party Onboarding. Third-Party Onboarding is uniquely set up to reduce friction for third-party data and the ecosystem in general."adam kobus, director of data partnerships Experian events at Cannes Lions 2024 This year, we hosted a kick-off happy hour, content studio, and members of our team joined various panels across the Croisette. Here’s a recap of our week at Cannes. Experian's kick-off event with Audigent and LG Ad Solutions To kick off the week, we co-hosted a happy hour with Audigent and LG Ad Solutions. At our sold-out event, attendees enjoyed a live performance from St. Lucia. Content studio We interviewed 27 thought leaders across the industry in our content studio. Our interviews covered topics like:• Signal loss• Connected and linear TV• Data collaboration• Future of addressability and personalization• Retail media networks• And more We'll be sharing more from our content studio over the coming months. Follow us on LinkedIn or sign up for our email newsletter for the latest updates. Panel participation The Experian team participated in four panels throughout the week across the Croisette: Scott Kozub, VP, Product Management, joined the Brand Innovators panel, "Future of media,” where he discussed how media companies can adapt their content and distribution strategies to cater to changing consumption habits as media becomes more fragmented across devices and platforms. Kimberly Gilberti, Chief Product Officer, joined OpenX's panel, "Unlocking addressability: Navigating the post-cookie era,” to discuss the prevailing strategies for achieving addressability in a cookieless world. Budi Tanzi, VP, Product, participated in Audigent's panel, "Curation in regulated industries,” where they talked about why curation is effective in regulated markets like finance and health. Rachael Donnelly, Chief Marketing Officer, joined The Female Quotient in the Equality Lounge for their panel "Emotional agility: Leading beyond the double standard," where they explored the power of diverse storytelling and its impact on audience engagement, brand building, and the bottom line. Let's keep the momentum going As we wrap up another exciting week at Cannes Lions, the discussions have shown us the potential for innovation in signal loss, TV fragmentation, AI, measurement, and retail media networks. These topics pave the way for a more connected future in advertising. Which trends are you most excited about? Let’s continue the conversation! Reach out to us, and let's dive deeper into these topics together. Stay connected We understand that customers may be experiencing uncertainty with their marketing strategies with Oracle’s exit from advertising. Experian is one of Oracle’s primary data providers powering their audiences. We can help marketers easily make the switch from Oracle audiences to Experian audiences without changes in advertising effectiveness or efficiency. We have mapped Oracle audiences to Experian audiences to make it easy for you to switch your campaign targeting to Experian. Reach out to your account representative or our audiences team for information about audience mapping and finding the most relevant Experian audience for your campaigns. Connect with our audiences team Latest posts

Cuebiq’s mission, as an offline intelligence and measurement company, is to deliver the most accurate and reliable insights on how digital marketing efforts impact offline consumer behavior. This case study shows how Cuebiq, despite signal loss, partnered with Experian to continue delivering in-store lift analyses. To achieve this, Cuebiq used Experian’s Activity Feed to resolve digital ad exposures to in-store purchases, so that marketers could know the effectiveness of their clients’ media campaigns. Activity Feed helped Cuebiq increase its match rates by using all the identifiers supported in Experian’s signal-agnostic Digital Graph, reducing its reliance on third-party cookies. By partnering with Experian, Cuebiq could help their clients, marketers, more accurately measure their campaigns and optimize their media. What is Activity Feed? Experian’s Activity Feed pulls together fragmented digital event data from all digital channels, including browsers like Safari and Firefox that restrict traditional tracking methods. Activity Feed ingests and ties this digital ad exposure data to household or individual profiles hourly, helping clients associate that data to offline purchase activity made by that household or individual. Activity Feed plays a crucial role in overcoming fragmented data and helping marketers accurately measure their cross-channel marketing efforts. Challenge: Increasing match rates across digital platforms Cuebiq wanted to enhance how well they connect digital ad exposures, across web, mobile and connected TV (CTV) to specific mobile ad IDs (MAIDs), of those who visited clients’ stores. They needed a single technology partner who could collect data across these environments and improve these connections, especially as iOS updates, like iOS 14.5, posed potential challenges. With the ability to resolve exposures to households, individuals, and MAIDs to then facilitate attribution of digital exposures to offline store visitation, Cuebiq could continue to provide accurate reports on how online ads impact offline consumer behavior. This clarity in data enables their clients to fine-tune their marketing strategies. Cuebiq’s key objectives included: Resolving digital exposures to MAIDs Increasing overlap of offline and online data Improving the effectiveness of offline measurement offerings Activity Feed: The solution to increase match rates Cuebiq used Activity Feed to resolve data from cookieless environments like Safari to a single household or individual and saw significantly higher match rates. Cuebiq was able to track cross-channel media exposures, resolve them to MAIDs, and then use the Activity Feed output to correlate in-store visitation and sales to their clients’ media campaigns. Cuebiq also implemented the Experian pixel, which they placed to track all their marketers’ impressions (mobile, CTV, web traffic, etc.). The Experian pixel collects information in real-time, such as: Timestamp Cookies Device ID (MAID/CTV) when available IP address User-Agent Impression ID “Before we started working with Experian, we couldn’t fully maximize ad views across the complex digital landscape. In just a few weeks, they were able to maximize the match rate across the fragmented digital inventory, solving a huge problem when it comes to cross-channel attribution.” Luca Bocchiardi, Director of Product, Cuebiq Results Activity Feed combines separate data streams and matches them back to a household. This enables Cuebiq to expand household IDs and accurately identify MAIDs that are seen in-store for cross-channel measurement. Over a 21-day period, Cuebiq passed ~1 billion events to Experian. Activity Feed resolved 85% of total events to a household, 91% of which were tied to MAIDs. By implementing Activity Feed, Cuebiq was successfully able to: Gain clearer insights into the success of their client‘s campaigns Match consumer engagements in a privacy-compliant manner Tell the story of the key performance indicators (KPIs) related to their marketing efforts Prepare for a cookieless future with higher match rates Activity Feed is prepared for a cookieless future and uses alternative IDs, like ID5 IDs, hashed emails, and IPs for identity resolution, ensuring no reliance on third-party cookies. Experian remains fully committed to exploring a suite of next-generation solutions and prioritizing continued testing of different industry solutions, including the Google Privacy Sandbox, to help customers prepare for a future without cookies. We’ve identified six viable alternatives to third-party cookies, how these alternatives fall short, and how Experian can help you navigate these alternatives. “Experian’s customer service is extremely efficient and collaborative. We trust them to keep putting our business first long-term.”Luca Bocchiardi, Director of Product, Cuebiq Download the full case study to discover how Cuebiq used Activity Feed to overcome their challenges. Your path to maximizing match rates and resolving data from cookieless environments starts here. Download the full case study About Cuebiq Cuebiq is transforming the way businesses interact with mobility data to providing a high-quality and transparent currency to map and measure offline behavior. They are at the forefront of all industry privacy standards, establishing an industry-leading data collection framework, and making it safe and easy for businesses to use location data for innovation and growth. To learn more, visit their website at www.cuebiq.com Latest posts

Today, Experian announced a suite of next-generation solutions that will help marketers navigate the challenges of cookie deprecation. Powered by the Experian Graph, these solutions will enable marketers to maintain behavioral targeting at scale. In partnership with Audigent, Experian announced the early-stage limited availability of Experian Audiences inside the Privacy Sandbox through the Protected Audiences API. Experian has also co-developed, with Audigent, an AI-driven contextual targeting solution layered with Experian’s rich Experian Marketing Data to continue delivering marketers scale and performance from their campaigns. Finally, Experian continues to evolve its signal-agnostic Graph, including coverage for industry-leading universal IDs, and plans to support IPv6 and phone-based UID2s. With these solutions, marketers can confidently deliver behavioral targeting after cookie deprecation and benefit from the power of Experian Marketing Data in their contextually targeted campaigns. As the industry prepares for ongoing signal loss and tightened privacy regulations, these solutions and further investments in Experian's identity Graph ensure Experian continues to power data-driven advertising and achieves the needs of modern marketers: addressable advertising, cross-device targeting, and measurement. Experian’s Graph allows marketers to target audiences in Privacy Sandbox via Audigent Building off Audigent’s work with Privacy Sandbox, Experian and Audigent tested the scale of Experian audience data in Privacy Sandbox and found that over 15 days, they were able to match audiences to over 150M Chrome browsers in the US. This solution – now in alpha – is powered by Experian’s Graph, leveraging an array of identifiers, including hashed emails and Hadron IDs. While the scale of targetable users and ad opportunities is still growing with the adoption of Privacy Sandbox by publishers and SSPs, the results are strong and provide a real-life illustration of how advertisers will be able to reach audiences in this new environment. “As the industry’s leader in building Interest Group segments in PAAPI, Audigent is thrilled to see world-class data partners like Experian work with us to build innovative solutions that deliver value now and will be absolutely critical as third-party cookies are deprecated in 2025.”DREW STEIN, FOUNDER AND CEO, AUDIGENT Data-driven contextual targeting is available through partnerships with Audigent and Peer39 As marketers prepare for cookie deprecation, they are turning to tried and true methods of targeting, like contextual, as they offer targeting strategies based on content and behavior instead of user identity. Experian is co-developing ID-less solutions that upgrade contextual targeting by intelligently indexing and infusing Experian’s rich Experian Marketing Data against contextual signals. By using these products, advertisers gain the ability to reach their audiences with a new and improved solution that delivers scale, performance, and value. We have beta launched a unique solution with Audigent that indexes Experian syndicated audiences against contextual signals through the power of the Experian Graph and Audigent’s Hadron ID to create PMPs that can be activated on any DSP. As part of the beta, a leading national advertiser ran a test via Audigent to see if this fully cookieless solution could deliver results at parity or better than today's ID-based options. The scaled 15-day flight not only met existing campaign delivery targets but also exceeded CTR goals by 25%. Experian has also partnered with Peer39 to make our geo-indexed syndicated audiences (e.g., Purchase Affinity and Demographic data) available through Peer39's contextual integrations. This allows marketers to confidently reach the right audiences in their digital marketing campaigns without third-party cookies. Experian's Graph now includes leading Universal IDs With the ever-changing nature of signal and identity, we’re continuing steps to be interoperable, and Experian's signal-agnostic Graph now supports the leading universal IDs: UID2s, ID5 IDs, and Hadron IDs. This is in addition to hashed e-mails, mobile ad IDs, and Connected TV IDs. Our strong coverage against cookieless identifiers means marketers will maintain addressable advertising as the Graph continues resolving data back to consumers and households in a privacy-centric way. In addition to providing greater breadth and depth of signals to reach US consumers, Experian's Graph is rebuilt weekly, which means our connections are highly accurate, refreshed, and addressable. “Experian is a valued partner in Nexxen's unified identity graph powering the Nexxen data platforms, which bring us the ability to seamlessly onboard client data, activate campaigns, and measure performance while maximizing biddable opportunities for our advertisers. They help ensure our clients can continue reaching audiences at scale and successfully execute campaigns.”Chance Johnson, Chief Commercial Officer, Nexxen Investments planned over the next year continue to ensure a Graph resilient to signal loss As connected TV (CTV) viewing continues to dominate, the importance of being able to match to IPv6 increases. Later this year, we’ll add support for IPv6 in our Graph as well as phone-based UID2s. This is in addition to our current coverage of IPv4 and email-based UID2s. As a result, all IP signals and UID2s will be resolved back to Experian’s household and individual profiles and their associated devices, which means marketers and platforms can better understand the full customer journey and reach people across their devices. Experian’s toolkit of cookieless solutions maintains addressability and ensures marketers can continue to do privacy-safe behavioral targeting at scale As the industry braces for the challenges posed by signal loss and evolving regulation, the unparalleled breadth, depth, and stability of Experian’s Graph empowers our partners across the ad tech ecosystem to confidently achieve their objectives and navigate uncertainty. What are you waiting for? Fill out the form to begin testing one of these cookieless solutions Get started About the author Budi Tanzi, VP of Product and Solution Engineering, Experian Marketing Services Budi Tanzi is the Vice President of Product at Experian Marketing Services, overseeing all Identity Products. Prior to joining Experian, Budi worked at various stakeholders of the ad-tech ecosystem, such as Tapad, Sizmek and StrikeAd. During his career, he held leadership roles in both Product Management and Solution Engineering. Budi has been living in New York for almost 11 years and enjoys being outdoors as well as sailing around NYC whenever possible. Latest posts