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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We spoke with industry leaders from Ampersand, Basis Technologies, Captify, Cuebiq, CvE, Fetch, Madhive, MiQ, and Samsung to gather insights on how innovations in data and identity are creating stronger consumer connections. Here are five key insights to consider. 1. Build on trust with first-party data Stricter privacy regulations and growing customer expectations mean businesses must rethink how they gather and use data. A robust first-party data strategy centers on gathering high-quality data, such as behavioral and transactional data. By using behavioral, lifestyle, and purchasing data, brands can craft personalized strategies that align with their goals. This approach balances effective targeting with building trust and complying with privacy rules. Integrating identity solutions like Unified I.D. 2.0 (UID2) and ID5 into existing data strategies improves interoperability across platforms while keeping user privacy intact. These tools help create more effective campaigns. "We've been preparing and leaning into educating our clients around the value of first-party data. These are very important and primary considerations in any of our campaigns."April Weeks, Basis Technologies 2. Align metrics with business goals To demonstrate clear value, campaigns need to tie their outcomes to broader goals. Relying only on click-through rates or CPMs won’t cut it. Metrics that measure meaningful results, like driving sales or increasing customer retention, provide greater transparency than surface level data, like clicks or impressions. A continuous feedback loop between targeting and measurement ensures campaigns can be refined to better align with business objectives. This feedback helps marketers understand who they are targeting and how those audiences are driving key business results. Shifting focus to metrics that resonate with stakeholders ensures that marketing efforts are evaluated based on their true contribution to the company's objectives. "The television industry has access to more data than ever before, and at Samsung Ads, our ACR technology helps us provide valuable insights about what content and ads are being viewed. This abundance of data enables us to support clients in aligning their campaigns with business objectives effectively."Justin Evans, Samsung Ads 3. Personalize experiences to boost engagement Personalization drives stronger customer relationships by delivering tailored experiences to individual customer needs. Using data-driven insights to fine-tune offers and messaging makes interactions more relevant, strengthening brand loyalty. Combining behavioral, lifestyle, and transactional data provides a comprehensive understanding of the customer journey and ensures each touchpoint feels personal. Testing and iterating on personalization strategies also helps identify which data and approaches yield the best results. Scaling these efforts means customers receive the right messaging at the right time, and businesses see better outcomes. "Every business should be building a data strategy that thinks about the different versions of data that exist and how they bring that together. They don't necessarily need to own all of it but have a clear rationale and strategy about where you're using which data sets."Paul Frampton, CvE 4. Utilize advanced measurement tools for smarter decisions Improving the effectiveness of campaigns starts with using sophisticated measurement tools to gain actionable insights. Using analytics like brand lift studies, foot traffic analysis, app download tracking, incrementality, and share of search allows marketers to understand the full impact of their efforts. With these resources, teams can pinpoint what’s working, make real-time adjustments, and refine their approach. This adaptability ensures budgets are used as effectively as possible. Learn how Swiss Sense measured marketing outcomes using Mosaic® "We are playing a leading role in democratizing new tools for local advertisers. By mimicking the marketing funnel mentality, we've introduced solutions ranging from measuring brand lift to tracking foot traffic and app downloads."Luc Dumont, Madhive 5. Adapt quickly to stay competitive The only constant in advertising is change. Adapting quickly to new technologies and consumer behaviors keeps businesses competitive. A culture of agility fosters innovation, making it easier to respond to industry shifts and discover new opportunities. Companies that anticipate change and invest in modern data solutions position themselves for long-term growth. Whether it’s adjusting to privacy updates, exploring emerging tech, or staying flexible, businesses must continuously invest in adapting their platforms and strategies. "Falling behind is not really an option. There's always a change in advertising and in data where there's a new horizon. The people who stay close to that and innovate will always follow it."Amelia Waddington, Captify Shaping the future Building meaningful consumer connections requires advertisers to combine robust data strategies with flexibility and innovation. By focusing on these five considerations, marketers can adapt to today’s challenges while preparing for what’s ahead. Connect with our experts Latest posts
Agencies, platforms, and marketers stand at the crossroads of transformation, as privacy regulations tighten, technology accelerates, and consumer behaviors evolve. Yet these challenges also present extraordinary opportunities. Our 2025 Digital trends and predictions report highlights five trends that will shape 2025 and digs into: What’s changing in the market How to keep learning about your customers How to reach your customers in different places How to measure what’s really working along the way In this blog post, we’ll give you a sneak peek of three of these trends — from cracking the code of signal loss to tapping into the buzz around connected TV (CTV) and stepping up your omnichannel game. Think of it as a taste test before the main course. Ready for the full menu? Download our report to get the lowdown on all five trends. Download now 1. Signal loss: A rich appetizer of alternate ingredients As traditional cookies crumble, marketers need fresh ingredients to keep the flavor coming. Already, about 40% of browser traffic doesn’t support third-party cookies, and marketers are spicing things up with first-party data, alternative identifiers like Unified I.D. 2.0 (UID2) and ID5, and contextual targeting strategies. In fact, 50% more of our clients received alternative IDs (UID2, ID5, Hadron ID) in their Digital Graph in 2024 compared to 2023. The number of alternative IDs resolved to individuals in our Digital Graph increased by 30% year-over-year – as everyone looks beyond the cookie jar. There is no secret sauce to replace cookies. Instead, expect a multi-ID recipe that brings together different identifiers, unified by an identity graph. This approach turns a fragmented pantry of data into a cohesive meal, giving you a complete view of your customer on every plate. 2. The rising power of CTV: A hearty entrée of opportunities CTV is quickly becoming the main dish on the streaming menu, as viewers load up on their favorite shows. While CTV is slated to make up 20% of daily U.S. media consumption by 2026, advertisers are still holding back on pouring in the ad spend. To unlock its full flavor, marketers need to whip up solutions like frequency capping and unified audience activation. Although CTV will account for 20% of daily U.S. media consumption by 2026, it’s projected to command only 8.1% of ad spend. Frequency capping and unified audience activation solutions will be key to unlocking CTV’s full potential. By 2025, nearly half of CTV "diners" will choose free ad-supported streaming TV (FAST). Marketers need strategies to prevent ad overexposure. With 50% of U.S. consumers avoiding products due to ad overload, and 30% of marketers willing to increase their CTV spend if frequency capping improves, unified identity solutions help ensure every impression is served just right. 3. Omnichannel: A flavorful fusion plate No one likes a one-flavor meal. Marketers are moving beyond single-channel “side dishes” to omnichannel “fusion feasts” that blend direct mail, digital, CTV, and retail media networks (RMNs) into a truly cohesive culinary experience. Even though only 21% of global B2C professionals currently put omnichannel at the top of their shopping list, the growing demand for seamless, audience-first campaigns is heating up. In 2025, having an audience-first approach will be like having a perfect pairing for every course. Unified identity solutions act as your master sommelier, ensuring that each channel complements the next, and every customer enjoys a well-rounded, memorable journey. Vertical trends: A dessert sampler from four unique kitchens Different markets have their own signature flavors. In Auto, crossover utility vehicles (CUVs) claim 51% of new vehicle registrations, and consumers in the 35-54 age group and families are the primary buyers. Automotive marketers should prioritize CUV advertising with a strong focus on family-oriented and income-appropriate messaging In Financial Services, marketers need to anticipate shifts in consumer behavior tied to economic conditions, such as increasing demand for deposit products when interest rates are high. For insurance, aligning campaigns with life events, like new home purchases or marriage, can maximize engagement. In Healthcare, advertisers are prioritizing personalized, regulation-compliant campaigns that address social determinants of health (SDOH). In Retail, advertisers are increasingly activating on both CTV and social platforms, with many managing their own in-house campaigns. While larger brands often rely on media agencies, a shift toward in-house media buying is emerging among some bigger players, offering more control over audience targeting and performance metrics. Our report covers each vertical’s unique menu, helping you select the right “ingredients” for your customers. With the top Experian Audiences on hand, you can create feasts that delight, nourish, and convert. Hungry for more? Download our full menu The three “samples” you’ve just tasted are just the starters. Our 2025 Digital trends and predictions report serves up five insights, complete with strategies, data, and tools to help you adapt, scale, and thrive in 2025. Ready for the full menu? Download our report now and discover all five trends that will shape your marketing “cookbook” in 2025. Bon appétit! Download now Latest posts