
The Case for Deterministic Identity: Why Marketers Need to Know Exactly Who They re Talking To
Discover how deterministic identity empowers marketers to reach real people, improve attribution, and respect privacy in a post-cookie world.
AI is fundamentally reshaping how people find and consume content, and publishers are feeling the impact.
Search engines now display AI-generated summaries at the top of results pages, often removing the need to click. At the same time, platforms like ChatGPT allow users to get answers without ever visiting the source. As these zero-click search experiences grow more common, traditional site traffic is disappearing.
Some publishers are already seeing the fallout. Year-over-year traffic declines above 50% are becoming alarmingly common. And as traffic drops, so do impressions, eCPMs, and overall revenue.
What makes this disruption different is the macro shift in user behavior. While publishers are accustomed to Google’s algorithm updates impacting search rankings, Google’s insertion of AI results is an attempt to dissuade users from visiting publishers entirely.
Overnight, Google evolved from a search engine into the world’s largest publisher, with a content library as vast as the open web.
As AI summaries cannibalize referral traffic, programmatic demand is increasingly concentrated among a smaller set of available inventory. With fewer visits, ad demand softens, audience signals weaken, and monetization stalls. The most compelling content can’t drive revenue if no one shows up to read it. To counter this decline, publishers must shift focus from traffic volume to traffic value.
In this zero-click reality, publishers need to find value in the audiences they still reach. That means anchoring monetization in deterministic identity resolution, not third-party ID bridging or passive browsing behavior.
Solutions like HIRO, powered by Zeta Global’s robust Identity Graph, help publishers make anonymous traffic addressable. By mapping first-party cookies and hashed emails to persistent identifiers, publishers can continue commanding a premium to deliver relevant ads, even when impressions are fragmented across browsers and devices.
This approach increases addressability and draws stronger demand from advertisers. Verified identities create better targeting precision, higher eCPMs, and new revenue streams from inventory that was previously unmonetizable.
HIRO’s impact is all the more significant in light of the macro declines in publisher traffic. Across a cohort of publishers active in both Q3 2024 and Q3 2025, total impressions declined more than 40% year-over-year.
Yet within that same group, eCPMs on HIRO-treated inventory grew by more than 16%, outperforming eCPM growth on non-HIRO inventory by over 50%.
For some partners, the results were even more striking. One of our largest HIRO-enabled publishers saw a 42% YoY increase in eCPM uplift compared to the control group, driven largely by improved bid density for addressable impressions.
As industry headwinds intensify, HIRO’s role as a stabilizing force for publishers continues to strengthen.
As referral traffic becomes less reliable, publishers are recalibrating their business models. Many are doubling down on first-party data, investing in newsletters and subscriptions, and building identity infrastructures that don’t depend on search engines to fuel monetization.
By enabling audience targeting across channels, HIRO supports this shift, even as cookies disappear and search behaviors fragment. Instead of chasing traffic that may never return, publishers can focus on activating and monetizing the audience they already have.
Generative AI’s influence on content discovery is far from over, and the dominant walled-garden behemoths will continue prioritizing their own interests over those of the broader publisher ecosystem.
That’s why the priority for publishers is to strengthen their existing traffic moat by enabling deterministic addressability at scale.
HIRO helps make that shift possible, empowering publishers to capture premium demand and sustain revenue in a landscape where attention is harder to earn, and more important than ever to monetize effectively. Publishers that invest in durable, identity-based monetization strategies are best positioned to future-proof their business model and continue to drive revenue.

HIRO for Publishers
Turn your anonymous traffic into targeted, addressable audiences and drive premium demand, higher eCPMs, and more revenue.

Zeta Identity Graph
With unique identity graphs and exclusive signals, Zeta empowers brands to truly know, find, and engage real customers with more accuracy and impact.

Discover how deterministic identity empowers marketers to reach real people, improve attribution, and respect privacy in a post-cookie world.

Watch to learn how first-party data and AI power direct relationships, real-time identity, and next-level customer engagement.

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