
We’re excited to introduce the next segment in our Q&A series, Ask the Expert! Ask the Expert features a series of conversations with product experts where we dive into the areas you care most about like identity resolution, targeting, attribution, and more. Our next segment features a conversation about sell-side targeting.
Mike Chowla, SVP of Product at OpenX joins us to chat with Experian’s SVP of Sales & Partnerships, Chris Feo. OpenX is the world’s leading sell-side platform for audience, data, and identity targeting. In their conversation, Mike and Chris review:
- The shift to targeting on the sell-side
- How first- and third-party data are being used on the sell-side
- How OpenX is thinking about alternative IDs

What is sell-side targeting?
Sell-side targeting optimizes the way buyers and supply-side platforms (SSPs) work together. This approach moves the responsibility of inventory and audience targeting from the demand-side platform (DSP) into the SSP, providing advertisers with increased reach and better performance.
With sell-side targeting, locating your target audience becomes easier as you have a more direct connection with publishers. This increases your ability to scale against a target audience. Specifically, the SSP directly matches the buyer’s audience or data segment to the publisher inventory and audience and automatically sends the impression to the buyer’s DSP of choice via a deal ID, providing advertisers with improved reach and performance metrics as well as control over their inventory. With more direct access, your budget can likely go further, and you can decrease your effective cost per mille (eCPM) and get more working media.
“Supply-side targeting is the next phase of how supply path optimization (SPO) and buyers will need to work more closely with SSPs.” – Mike Chowla, SVP, Product, OpenX
Buying on the sell-side vs. open exchange
When buying on the open exchange, you have access to a vast number of impressions. With sell-side targeting, you can apply your campaign targeting directly on the supply-side and activate those impressions through a deal ID. Sell-side targeting works across various formats including web display, mobile, in-app, and connected TV (CTV) for a seamless advertising experience.
OpenX offers the unique capability to match users using their device graph within their SSP. This means you can target users from traditional data sources such as cookies or mobile ad IDs (MAIDs) and reach them in CTV or app environments. This gives you even more reach and precision in your advertising efforts.
The role of first- and third-party data on the sell-side
Buyers are showing a keen interest in bringing their own first-party data into the process of sell-side targeting. Meanwhile, certain agencies have been actively involved in working with identity and data. OpenX is currently collaborating with several agency ID solutions such as Choreograph, Merkel, and Horizon.
Buyers are also purchasing third-party data and data segments from various providers through OpenX’s platform for sell-side targeting purposes. By utilizing this data on the supply side, buyers are able to increase the match rate against their first- and third-party data segments in all environments. This ultimately maximizes scale against these audiences and drives a more efficient CPM due to eliminating waste.
Measurement and attribution on the sell-side
In the current state of SSP advertising, there is more of an emphasis on targeting capabilities than measurement and attribution. That said, SSPs can provide granular log level reports that can be utilized for multi-touch attribution (MTA) or mixed media models (MMM). These granular insights not only inform measurement and attribution models, but they also provide valuable optimization insights such as clearing price.
Additionally, advertisers have all of the same reporting options that they’re used to getting through their DSP because their buys are activated via deal ID in the DSP of their choice.
What to consider when transitioning to sell-side targeting
There are two primary items you should consider when transitioning to sell-side targeting:
- Supply
- Reach
Reach
Collaborating with partners who have the right capabilities can greatly improve reach and audience extension across different devices. For instance, if you bring your first-party audience or a third-party audience and are identifying that consumer via a cookie or MAID, being able to extend that targeting segment to other devices and platforms can be highly beneficial.
Supply
It’s crucial to collaborate with partners who have the right access to supply and direct connections with publishers. While targeting is essential, it’s equally important to have high-quality supply to drive performance.
Reaching consumers in a cookieless future
Whether you’re targeting on the demand or sell-side, it always starts with the consumer and who you’re trying to reach.
Significant changes in the consumer privacy landscape are impacting advertisers’ ability to access various signals emitted by consumers through their devices and browsers. Recent developments from Apple and Google have further amplified this situation.
Alternative IDs as a solution to signal loss
In response, we’re seeing the emergence of alternative IDs like UID2, Ramp ID, and ID5. OpenX supports these types of IDs and considers them crucial for audience buying in a privacy-centric cookie-less future.
We are still in the early stages of this evolution. While some of the IDs have good coverage, cookies will continue to be the primary targeting method as long as they remain available.
Nevertheless, we see alternative IDs as one of several solutions that will become increasingly important as third-party cookies disappear. Contextual buying will also emerge, and a set of solutions will come together to enable advertisers to keep finding their audience in a cookie-less world.
Overcoming signal loss with identity resolution
Looking ahead, as we continue to lose signals due to the evolving consumer privacy landscape, we will witness two things:
- Continued fragmentation
- A wide variety of identifiers
Content will continue to be available on various devices. We’re currently experiencing the emergence of connected TV, but who knows what other devices will surface over the next five to ten years. As cookies disappear, which have been the primary identifier, and alternative IDs are introduced, the wide variety of identifiers will create further fragmentation. This highlights the need for identity in the future.
Identity resolution at Experian matches fragmented identifiers to a single profile to create a unified, cross-channel view of your consumers. Our identity resolution solutions can help future-proof your marketing strategies.
How Experian and OpenX work together
Experian is a key player in OpenX’s OpenAudience solution and helps to power many of their data segments as well as their identity graph. While OpenX collaborates with a variety of providers and operates a fully interoperable platform, Experian remains valuable to the core technology within OpenX’s SSP.
“Experian powers a lot of the data segments and identity graph that OpenX has in our OpenAudience capabilities as part of our SSP.” – Mike Chowla, SVP, Product, OpenX
Watch the full Q&A
Visit our Ask the Expert content hub to watch Mike and Chris’s full conversation on sell-side targeting. In the Q&A, Mike and Chris also share their thoughts on the impact artificial intelligence (AI) will have on the AdTech industry and their go-to sources for staying up to date on all things AdTech.
About our experts

Mike Chowla, SVP, Product, OpenX
Mike Chowla is the SVP of Product at OpenX where he leads product development and innovation, from customer discovery and user research to the development, delivery, and support of a market-leading product suite. Chowla holds a BS in Engineering from the University of Southern California, and an MBA from The University of Pennsylvania.

Chris Feo, Chief Business Officer, Experian
As SVP of Sales & Partnerships, Chris has over a decade of experience across identity, data, and programmatic. Chris joined Experian during the Tapad acquisition in November 2020. He joined Tapad with less than 10 employees and has been part of the executive team through both the Telenor and Experian acquisitions. He’s an active advisor, board member, and investor within the AdTech ecosystem. Outside of work, he’s a die-hard golfer, frequent traveler, and husband to his wife, two dogs, and two goats!
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Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris rhoncus augue sit amet mi rutrum, et egestas neque hendrerit. Aenean quis lectus dui. Quisque vitae posuere lectus. Nulla varius tincidunt mauris ut pharetra. Pellentesque semper mauris risus, et varius ante pretium ut. Duis varius ante a augue sodales, in consequat augue vehicula. Suspendisse potenti. Donec massa leo, efficitur vel eros ac, facilisis luctus massa. Ut pharetra eros diam, in fringilla neque elementum et. Morbi velit mauris, blandit et congue eu, convallis non augue. Curabitur porta sodales tellus vel porta. Morbi vel felis non neque efficitur venenatis. Nullam lobortis blandit ex id mollis. Donec euismod iaculis rutrum. Heading Description Heading Description Heading Description Vestibulum sed quam elit. Quisque bibendum nulla quam, non gravida tellus venenatis id. Ut a tellus facilisis, elementum ipsum ut, sodales orci. Nullam justo leo, condimentum in volutpat eu, gravida vel est. Ut placerat nulla erat, vel finibus lorem gravida at. Vivamus quis est id diam rhoncus blandit. Cras dignissim auctor diam, lobortis consectetur felis. Nulla accumsan lorem et augue pulvinar fermentum. Quisque ac nisl suscipit, imperdiet mauris eget, dignissim augue. Quisque tempus condimentum rhoncus. Vivamus in blandit nisi. Suspendisse sed metus rhoncus, vehicula nulla laoreet, volutpat neque. Morbi viverra in lacus id gravida. Aliquam velit ex, blandit at metus a, efficitur rutrum tortor. Fusce facilisis, nulla eget dapibus sagittis, sapien justo rhoncus nisi, ut placerat velit orci at velit. Sed finibus turpis ligula, et fermentum ligula rhoncus sit amet. Our 2026 Digital trends and predicitions report is available nowand ereveals five trends that will define 2026. From curation becoming the standard in programmatic to AI moving from hype to implementation, each trend reflects a shift towards more connected, data-driven marketing. The interplay between them will define how marketers will lead in 2026. Download now

Why an identity framework matters more than any single identifier The challenge facing marketers today isn’t a single identifier on a deprecation timeline. It’s the increasing fragmentation of signals and identifiers across browsers, devices, apps, and platforms. This shift introduces complexity into how audiences are reached and measured, as signals behave differently in every environment, and it becomes more complex to piece together a complete view of the consumer. Each environment contributes to its own set of visibility gaps, making identity less predictable and more uneven. The result is a patchwork of inconsistent identity signals rather than a single, predictable decline. While you can’t control how platforms evolve, you can control how you respond to fragmentation. The future won’t be defined by the loss of any single identifier, but by your ability to unify, interpret, and activate the many signals that remain. Marketers who adopt a flexible, identity framework will be best positioned to create consistency in an otherwise fragmented landscape. At Experian, we believe flexibility starts with intelligence. For decades, we’ve used AI and machine learning to help marketers understand people’s behavior more clearly, respect their privacy, and deliver messages that drive business outcomes. Our technology brings identity, insight, and intelligence together, so even as the number of signals grows and becomes more varied across environments, marketers can reach the right people with relevance, respect, and simplicity. This intelligence acts as the connective tissue across fragmented ecosystems, ensuring marketers can recognize and reach audiences consistently wherever they appear. What forces are driving fragmentation in identity and signals? Changes to traditional IDs: Since Apple introduced ATT, access to IDFA has become inconsistent across apps and devices. Google’s evolving Android privacy roadmap adds another layer of variability, fragmenting mobile addressability. Safari and Firefox have long restricted third-party cookies, while Chrome continues to support them for now. This creates different signal availability across browsers, contributing to an uneven and increasingly fragmented identity landscape on the open web. Shifts in signals: IPv4 to IPv6 migration introduces mismatched identity structures that complicate continuity across environments. Platform-driven fragmentation: Closed ecosystems and uneven adoption of evolving RTB standards (like OpenRTB 2.6 updates designed to support new identifiers and consent signals) create differences in which identifiers and consent signals are shared in the bidstream. At the same time, the rise of alternative or “universal” IDs—often developed by individual platforms, publishers, or technology companies—means that multiple ID types can appear within the same auction, each with its own structure, rules, and level of support. These differences reduce interoperability across platforms and contribute to a more fragmented activation landscape. Each change creates an identity silo. Together, they form an ecosystem defined by fragmentation rather than absence. Without an identity framework, these environments operate as disconnected identity islands. A multi-ID world requires a unified identity framework Alternative IDs play an important role, but they also expand the number of signals marketers must reconcile. Without a consistent identity layer, more IDs often mean more complexity—not more clarity. Common alternative IDs in use today: UID2: The Trade Desk’s UID 2.0, an iteration of their original Unified ID 1.0, which was still reliant on third-party cookies, creates persistent IDs with user-provided email addresses and phone numbers. ID5: This independent identity provider builds an identity infrastructure that powers addressable advertising across channels. It can create an ID based on both deterministic and probabilistic data. Hadron ID: Hadron ID is a unique, interoperable identity system (including first-party, audience-based, contextual, deterministic, and probabilistic) developed by Audigent, now part of Experian, to drive revenue for publishers by making their audience data and inventory actionable for media buyers. Industry reports suggest roughly one-third to two-fifths of open-auction traffic carries alternative IDs, sometimes multiple per request. Among Experian clients, adoption of alternative IDs rose 50% year over year, with a 30% increase in IDs resolved to individuals via our Digital Graph. Identity isn’t disappearing; it’s multiplying. A modern identity framework resolves these identifiers into a single, privacy-safe consumer view.

Year after year, CES signals where marketing is headed next. In 2026, the message was clear. Progress comes from connecting data, intelligence, and outcomes with discipline, not spectacle. Across AI, programmatic media, and measurement, the same priorities surfaced again and again. Under the bright lights of Las Vegas, three themes cut through, and each one pointed to a future where data, intelligence, and outcomes move in lockstep. Here are the three themes that defined CES 2026. 1. Agentic AI proved that it’s only as good as its data inputs AI was once again the star of the show. At CES 2026, marketers focused less on demos and more on proof that AI improves decisions, reduces friction, and drives outcomes. Every credible use case traced back to accurate, privacy-first data. What changed at CES was how that intelligence is being applied. Agentic AI systems designed to act autonomously are moving beyond insights and into execution. From media buying to optimization, these agents are increasingly expected to make decisions at speed and scale. That shift raises the stakes for data quality. When AI is operating campaigns, not just informing them, accuracy and privacy are non-negotiable. Without accurate, privacy compliant data, AI agents struggle to reflect real behavior or support responsible personalization. A reliable, privacy-first data foundation is what turns AI from an interesting experiment into an operational advantage. That advantage gets even stronger when it’s anchored in an identity graph that understands people and households across channels. When identity and intelligence move together, AI becomes more accurate, accountable, and effective at driving outcomes. In an AI first world, the strongest signal isn't scale. It's data quality. 2. Curation goes mainstream Curation is no longer experimental. At CES, it showed up as an mandated capability for buyers and sellers navigating fragmented signals and complex supply paths. Marketers want intentional media buys they can explain, defend, and repeat. AI is accelerating this shift. As AI systems take on more responsibility for planning, packaging, and optimization, curation provides the guardrails. It defines what “good” looks like (premium supply, trusted data, and clear performance goals), and allows AI to operate within those constraints driving the optimal outcomes for marketers. Rather than maximizing inventory access, curation prioritizes control, transparency, and performance. Buyers want premium supply aligned to specific goals. Sellers want clearer paths to demand. They can play the odds or own the outcome. When data leads, they own it. When curation is powered by high-fidelity audiences and a connected identity framework, it becomes even stronger. That’s what allows curated deals to deliver clarity, confidence, and repeatable performance. This shift reflects a broader move away from probability-based buying toward outcome ownership, where AI-driven systems are measured not on activity, but on results. 3. Activation and measurement finally shared the same stage Activation and measurement are now coming together around shared data and identity. CES 2026 marked a turning point where closing the loop felt achievable, not aspirational. Both the buy- and sell-sides face pressure to show that media investment drives outcomes. Agentic AI was a quiet driver of this optimism. As AI agents increasingly manage activation decisions in real time, marketers need measurement systems that can keep up. That requires a shared data and identity foundation. One that allows AI-driven actions to be evaluated against outcomes consistently, across channels and partners. "The companies leading in alternative data aren't just optimizing for growth, they're setting a new standard for inclusion, precision and responsible lending." – Ashley Knight, SVP of Product Management, Experian Achieving that requires a consistent identity spine that connects planning, activation, and outcomes across channels. And that spine is strongest when it’s built on accurate, privacy-first data and audiences that understand people and households. That connection allows marketers to move beyond proxy metrics and evaluate performance based on tangible results. When campaigns and measurement rely on the same data foundation, AI driven platforms can optimize toward outcomes such as new customers, account growth, or in-store activity, not just delivery metrics. That’s the connective layer that turns disconnected touchpoints into a measurable, outcomes-based system. The takeaway CES made one thing clear: agentic AI is moving marketing from intention to execution. But only for teams with the right foundation. AI is maturing, but only for teams with accurate, connected, privacy-first data that AI agents can act on responsibly. Curation is scaling, giving both humans and AI systems clearer paths to quality, control, and differentiation. Activation and measurement are aligning, allowing AI-driven decisions to be judged on outcomes, not assumptions. We’re building for that world today. One where agentic AI operates on a trusted data and identity foundation, curation defines the rules, and outcomes determine success. With the right foundation and the deep data inputs, you can move faster, reduce risk, and let intelligence (human and artificial) work together to deliver results that last long after the neon lights fade.