
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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NEW YORK, May 4, 2016 /PRNewswire/ – Tapad, the leader in cross-device marketing technology and now a part of Experian, has been honored with two iMedia ASPY Awards. Announced on May 3rd at the iMedia Summit in Lost Pines, TX, Tapad's 2016 ASPY Awards include "Best Customer Service" and "Best Mobile Partner." In 2015, Tapad's proprietary technology, Tapad Device Graph™, was named "Best New Media Innovation" and Tapad employee Chris Martin was awarded the "Rising Star Award." The iMedia ASPY Awards – determined exclusively by agency votes – recognize the industry's top marketing technology, media companies and publishers for outstanding service to agencies. The award for "Best Customer Service" recognizes Tapad's client services team and their dedication to helping agencies fully understand their consumers' behavior and achieve the best cross-screen campaign ROI through Tapad's Campaign Pulse and TV Pulse analytics reporting. The "Best Mobile Partner" win recognizes the abilities of the Tapad Device Graph™ to deliver unified cross-screen solutions for the company's partners. "We are privileged to have a talented and dynamic group of people on our client services team, and we are honored to be recognized by iMedia Connection and our agency partners," said Tapad Founder and CEO, Are Traasdahl. "We have always strived to provide the best solutions and the best customer support, so it's extremely gratifying to be rewarded for our efforts. If our clients and partners are happy, we are happy." For more information on the iMedia ASPY Awards please visit: http://aspyawards.com. Read the full press release here. Contact us today!

This article is an excerpt from Experian Marketing Services’ 2016 Digital Marketer Report. Download the full report to discover more insights and trends for the upcoming year! Support your mobile app with other mobile marketing initiatives Marketers are fascinated by mobile, and for good reason. It’s increasingly the device of choice for consumers. SMS and MMS messages, push notifications and the app inbox all offer marketers the ability to communicate directly with customers in a way that is immediate and friendly. Yet there seems to be an interest gap between developing mobile apps and building other mobile initiatives. In this year’s Digital Marketer Survey, 53 percent of respondents indicated that they plan to integrate a mobile app into their mobile marketing program in 2016, compared with only 40 percent for other mobile programs like SMS or MMS. Without a doubt, well-designed apps can be incredibly useful for building the brand relationship. Good apps focus on improving the customers’ experience by making their lives easier – by tailoring the content to their personal experience or lessening the number of steps it takes for them to perform an action. In service-based industries, apps can alleviate the need for in-store or in-branch services, helping companies become more lean and efficient. For example, consumer bank apps have redesigned the experience of depositing a check or transferring money between accounts, allowing them to cater to their customers’ needs faster and more efficiently than ever possible through a physical teller. That said, mobile apps are also time- and resource-intensive to develop, especially if they are well designed. Other mobile initiatives, like SMS and MMS text messaging programs or mobile wallet, require less investment to create and maintain. Additionally, imagine if every marketer who shared a plan to build an app actually followed through. That would mean a lot of competition for customers’ limited phone space. This is why I find the interest gap fascinating. Mobile apps are useful, but they should be part of a cohesive mobile strategy, supported with other mobile programs like SMS and MMS messaging that are less costly and can serve as an effective alternative for communicating with customers who have push notifications disabled, are inactive users, don’t have compatible phones or simply haven’t downloaded your app. Business needs can dictate mobile marketing strategy This concept is especially important for brands that use the mobile space to communicate service-related or operational messages, such as shipping and delivery notifications, fraud alerts or travel delay notices that require immediacy. These kinds of messages are time-sensitive and valuable. Customers who don’t have your app will benefit from their receipt if you offer it to them via another channel. Of course, it’s important to remember that not every business fits usage of SMS and MMS or app programs. Consider the needs and preferences of your unique customers to determine the need to develop a mobile program. After all, mobile experiences that are not well thought through may be more damaging than beneficial. According to a Google study of smartphone users, 66 percent of consumers will take negative action if a mobile site or app doesn’t satisfy their needs, such as being less likely to return to the site or app (40 percent) or purchase products from the company in the future (28 percent). Ultimately, if you’re investing in a mobile app experience, don’t forget about the power of a complimentary text message strategy. Mobile app marketing and text messages can go hand in hand. Develop an SMS experience that proves the value of your brand in the mobile space. Once you do, your customers and prospects will be more likely to believe in the value of your full app experience.

Cross-screen marketing tech firm, Tapad, drove unified campaign; partnered with Statiq to measure cross-screen impact on in-store visits LONDON, March 8, 2016 /PRNewswire/ — Carat North completed the UK's most comprehensive digital campaign with Tapad, the leader in cross-device marketing technology and now a part of Experian. Coupled with location-based audience data from Statiq, this marks the first time a UK-company has measured the impact of unified, cross-screen campaign on in-store visits. Carat North served display and video ads to grocery shoppers for the leading retailer ASDA from August through October. During the campaign, Tapad utilized Statiq's audience data to measure which users visited a store after being exposed* to the campaign's ad on multiple devices. The digital campaign demonstrated a lift of 59% for in-store visits when users were exposed to ads on three devices over people who were shown an ad only on onescreen. Those who engaged with the ad were also 411% more likely to visit an ASDA store. Of those who were exposed to an ad, 248% were more likely to visit a store. Impressions served to mobile devices saw the highest success rate with an in-store visit lift of 67%. The campaign leveraged Tapad's proprietary technology, The Device Graph™, which Nielsen confirmed Tapad's cross device accuracy to be 91.2%, to serve ads sequentially on connected devices belonging to the same user. CARAT NORTH: "The ability to know which devices belong to our customer, coupled with the ability to deliver the right ad, and right message, wherever they are and on whatever device they're using, has been something this industry has long needed," said Steve Thornton, Digital Account Manager, Carat North. "We're impressed with the results that have come from the work with Tapad and Statiq for this media-first, and look forward to continuing to offer these solutions to clients like ASDA. Matching unified cross-device capabilities with real insights on campaign performance is an invaluable advantage in the marketing world." TAPAD: "This campaign is a perfect example of the capabilities of cross-device advertising," said Are Traasdahl, Founder and CEO, Tapad. "In addition to reaching users across devices, we're able to analyze campaign results and determine how different combinations of ad exposure, creative type or view frequency affected their decision to visit a location." STATIQ: "As a location data specialist, Tapad is our ideal partner – they are an industry leader and by working with them we are able to determine the impact unified messaging has on real world consumer behaviours," said Dean Cussell, Co-Founder of Statiq. "We believe this type of analysis will significantly aid brands in optimising future ad spend." About Carat North Carat North is a leading independent media planning & buying specialist in digital and non-traditional media solutions. Owned by global media group Dentsu Aegis Network, the Carat network is more than 6,700 people in 130 countries worldwide across 170 cities. Carat defined the sector when established as the world's first media independent in 1968 and is now Europe's largest media network, a position held for more than 15 years. For more information visit www.carat.co.uk About Tapad Tapad Inc. is a marketing technology firm renowned for its breakthrough, unified, cross-device solutions. With 91.2% data accuracy confirmed by Nielsen, the company offers the largest in-market opportunity for marketers and technologies to address the ever-evolving reality of media consumption on smartphones, tablets, home computers and smart TVs. Deployed by agency trading desks, publishers and numerous Fortune 500 brands, Tapad provides an accurate, unified approach to connecting with consumers across screens. In 2015, Tapad began aggressively licensing its identity management solution, the Tapad Device Graph™, and swiftly became the established gold-standard throughout the ad tech ecosystem. Tapad is based in New York and has offices in Atlanta, Boston, Chicago, Dallas, Detroit,Frankfurt, London, Los Angeles, Miami, Minneapolis, San Francisco and Toronto. TechCrunch called the powerhouse Tapad team "a hell of a list of entrepreneurs who created some of the most valuable online advertising companies of the last decade." Among Tapad's numerous awards: EY Entrepreneur of The Year (East Coast) 2014, among Forbes' Most Promising Companies two year's running, Deloitte's Technology Fast 500, Crain's Fast 50, Entrepreneur 360, Digiday Signal Award, iMedia ASPY Award, and a MarCom Gold Award. Read the full release here. *Tapad utilized Statiq's audience data to measure which users visited a store during, or within one month of, being exposed to the campaign's ad on multiple devices. Contact us today!