
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.
Latest posts

Even though most kids haven’t even completed their current school year, now is the time for retailers to start preparing their 2012-2013 back-to-school marketing strategies. I remember growing up as a kid in rural Massachusetts thinking about how “back-to-school” TV ads were so irritating. Back-to-school? In July? I’m not even half way through my summer vacation! Little did I know back then that marketers like to get an early start to the back-to-school sales season by planting seeds with their target audience and hoping those seeds grow into a healthy crop of new customers. This remains true today and planting season starts even earlier. The back-to-school sales season represents a huge opportunity for marketers. Here are some facts and figures that help quantify the size of the market: According to the National Retail Federation, consumers will spend approximately $70 billion on back-to-school merchandise. About $23 billion of this is spending by parents of children in kindergarten through 12th grade. The remainder represents spending by students starting or returning to college. All told, the back-to-school season is the second largest consumer spending event for retailers outside of the winter holidays. According to the U.S. Census Bureau, this year there will be over 55 million students enrolled in schools from pre-kindergarten through high school. About 56% of these students are in grades one through eight, 28% are in high school and 15% are enrolled in preschool or kindergarten. About one-third of households contain children under age 18. That translates to roughly 38 million households. The vast majority of these contain school-age children. The back-to-school season is not just about reaching kids in elementary school, middle school, junior high school and high school. Another 20 million students are expected to be attending college. That’s a huge opportunity to sell things like dorm room furnishings, electronic gadgets and computers, just to name a few. With every marketing opportunity come certain marketing challenges. It’s never easy. Marketers of back-to-school products face their own set of challenges when vying for the attention of parents of school-age children. Here are some specific examples: Who are my key targets and how can I differentiate my marketing message? Targeting a market that includes a vast array of families with contrasting attitudes, opinions, motivations, lifestyles and shopping behaviors is incredibly challenging. Not all of these families are working from the same shopping list. And not all of these families will respond to the same marketing message. Segmenting your market into finer target audiences is highly recommended. How should my marketing budget be allocated across multiple online and offline channels? You have multiple sales and marketing channels to consider. You don’t want to build a marketing plan without a well-defined strategy for reaching your best targets. For instance, moms have a greater propensity to have a smartphone compared to the overall adult population. Thus, marketers should then be thinking about integrating mobile applications into their overall strategy. What can I do to make my message stand out above the crowd? Put yourself in the consumer’s shoes. I’m sure some of you are parents with children in school or in college. It’s a very crowded and cluttered back-to-school marketplace with many, many retailers clamoring for attention. One idea for standing above the crowd is to start by identifying your existing customers who are most likely to have families with children. Then send them an email early in the summer with suggestions for fun things to do this summer season. This can be followed up later with an email campaign containing some tips about getting ready for back-to-school. The key is to grab their attention and start engaging early. What variety of offers and promotions will enable me to capture a significant share of back-to-school expenditures? To capture your fair share of the back-to-school market you’ll need to develop offers and promotions that are both enticing and relevant. This requires learning as much as you can about your prospects and what motivates them to buy. For instance, a typical mom with elementary school-age children might enter the back-to-school season with the following thoughts: “I want to buy him the cool gear to go back to school with: new clothes, shoes, backpack and lunch box. And I don’t mind, I actually LOVE back to school shopping.”* That mom may quickly respond to your marketing message. Or, you could have a mom with these thoughts: “I’m not upper class – we’re in the lower/middle income bracket and money is tight for us. I budget for school expenses as I would anything else…and I won’t have my son miss out because ‘we can’t afford’ something… I’d give up something else first.”* She loves shopping for back-to-school, she has budget limitations, and she’s willing to make certain adjustments to her budget with the best interests of her child in mind. If you knew what she was most likely to be thinking, do you think it would influence the messaging and offers you would use to attract her? Well, of course. Attitudes shape shopping behavior. ___________________________________________________________________________________ Watch our recent webinar about planning your back-to-school marketing campaigns in style. And stay tuned for part two of my blog series on the topic in a few days. *Feedback was compiled from PHD in Parenting: http://www.phdinparenting.com/2011/08/22/who-should-pay-for-school-supplies/

Facebook has become a cultural phenomenon over the years and an object of affection for marketers to connect with its users. Experian Simmons has put together 10 consumer behavioral stats based on their National Consumer Study and New Media Study about the social networking site leading up to its Friday IPO launch: 39% of Facebook users say “this website gives me something to talk about.” Top 3 reasons Facebook users visit social networking sites: 86% to keep in touch with friends 72% for fun 66% to reconnect with/find people they’ve lost touch with 78% of Facebook users have shown support for a group or business on a social networking site. 34% of Facebook users have played games on a social networking site. Among those: 73% play social games (like Farmville, SIMS social, etc) 68% play casual games (like Bejeweled, etc) 73% play games on a social networking site once or more a day 28% of Facebook users with cell phones and 42% of Facebook users with a tablet computer have downloaded a social networking app for the device Adult residents of the following Designated Market Areas (DMAs) with 1,000,000 or more adult residents are the most likely to have visited Facebook in the last 7 days: ) Seattle-Tacoma, WA Austin, TX Salt Lake City, UT Portland, OR Washington, DC 15% of Facebook visitors follow a musical group on a social networking site, 14% follow a TV show, 11% follow a newspaper or news outlet and 4% follow a magazine. The average Facebook user is 39.3 years old. The average Facebook user claims an annual household income of $69,900 with annual household spending on discretionary goods and services of $15,500. Hispanic users of Facebook are 55% more likely than non-Hispanic users to say they like to follow their favorite brands or companies on social networking sites. Don’t miss 15 stats about Facebook, previously posted on the Experian Marketing services blog. . For more information like the data provided above please download the Experian Marketing Services 2012 Digital Marketer report.

Today, it costs more than $40 to send a five pound package from the U.S. to Canada or Mexico. The cost to Europe or South America is even more expensive. For U.S. companies operating on a global scale, such as retail specialists or ecommerce organizations, address accuracy is crucial. Organizations can’t afford undeliverable mail and packages due to a wrong address – the total cost would be unmanageable. Mistakes happen frequently, whether it is an error by the company or the customer. If a mistake is made, companies can’t ask the customer to cover delivery fees, leaving the organization with the bill. Retailers must also consider potential delays due to long distances and custom checks. Altogether, address errors result in a poor customer experience and a decrease in efficiency. Implementing international address verification will save money, time and improve the customer experience. By combining primary address data from national postal authorities with partner-supplied data, businesses can verify international addresses from countries all around the world.