Why the Future of Open Web Addressability Has Us Optimistic

Embracing a privacy-centric future for digital advertising.

I. Introduction: The Great Digital Reset

The digital advertising market is shifting as third-party cookies fade out. What looked disruptive at first now feels like a chance to build something healthier and more durable.

Open Web Addressability, the ability for advertisers to reach audiences outside Google and Meta, supports a strong open internet and keeps independent publishers and creators competitive.

The change has helped the broader ecosystem more than expected. It pushes the market away from intrusive tracking and toward privacy-forward approaches. That shift encourages competition, innovation, and clearer value across ad tech.

II. A Walk Down Memory Lane: How We Got Here

The Cookie's Reign (and Why It Fell)

Third-party cookies powered cross-site tracking, audience building, ad targeting, and measurement. They also operated without user visibility, which drove regulatory pressure. GDPR and CCPA reshaped expectations for transparency and control, accelerating the decline of third-party tracking.

The Browser Rebellion

Safari and Firefox moved early with ITP and ETP. Chrome signaled an end to cookies as well, but repeated delays created uncertainty. With Google’s shifting timelines, the market stopped waiting and began adopting universal identifiers and first-party data to future-proof addressability.

The "Addressability Gap"

Losing third-party cookies created an addressability gap for publishers, sales houses, and SSPs. Many depended on cookies for monetization. Marketers also faced the risk of deeper reliance on high-margin walled gardens.

III. Reason 1 to Be Optimistic: A Multi- Currency Ecosystem 

The Problem with a Monopoly

Letting a single company control identity and pricing would choke competition, slow innovation, and raise costs. The industry just stepped back from one dominant ID system. No one wants to replace it with another.

Enter the Diverse Identity Solutions

Multiple privacy-centric identity options are now in circulation.

Universal IDs like UID2, Hadron, Panorama ID, and ID5 use hashed emails or phone numbers with consent. Others use IP-based or signal-based approaches to support addressability.

Why This is Great News for Everyone

The proliferation of multiple identity solutions fosters competition, drives innovation, and lowers costs. Advertisers and publishers have more flexibility to choose ID currencies that best fit their needs, leading to more tailored and effective campaigns and avoiding exorbitant rates from a single vendor.

IV. Reason 2 to Be Optimistic: The Sell-Side Signaling horse has left the barn…

The Goldmine: First-Party Data

As cookies disappear, the direct connection between publishers and their users becomes central. First-party data can be authenticated, contextual, declared, or behavioral. 

• Authenticated: Verified user logins.
• Contextual: Based on content being viewed.
• Declared: Information explicitly provided by users.
• Behavioral: Based on user interactions on the publisher's site.

What is Sell-Side Signaling?

Sell-side signaling involves publishers sharing their audience insights with advertisers in a privacy-safe manner, allowing advertisers to leverage publisher first-party data for improved targeting and campaign performance. Examples include:

• Publisher-defined audience segments based on first-party data can be shared with advertisers via the bidstream. While the IAB Tech Lab's Seller Defined Audiences (SDA) haven't really taken off. The core concept has. The use of validated seller data as a currency for targeting has reached the mainstream. And with the advent of LLMs and AI, there are a myriad of new taxonomies, including ones that brands invent themselves that can be deployed against publisher first-party data using the UID ecosystem discussed above.
• Publisher Provided Signals (PPS): Publishers pass anonymized user signals to Google's advertising platform for more relevant ad targeting.
• Curation:  Structured media products, such as sell-side Curation, provide the ability for publishers to signal segments based on strong first-party and zero-party signals from the publishers.  Such bespoke products offer the buy side the ability to target micro-cohorts at scale using their own first-party data and to match it to the publisher's first-party data signals.

Empowering Brands with Existing Investments

• Brands can utilize publisher first-party data through signaling mechanisms, enhancing targeting without third-party cookies.
• This often integrates with existing ad tech investments like Customer Data Platforms (CDPs) and Data Management Platforms (DMPs), minimizing disruption and maximizing ROI.
• Data Clean Rooms also provide secure environments for collaboration without revealing raw data, enabling valuable insights and improved advertising effectiveness while maintaining user privacy and data protections.

The Impact

Moving to first-party data and signaling helps publishers monetize better, helps brands target more accurately, and keeps user privacy central. The ecosystem becomes more durable and more aligned with user expectations.

Your Role in the New Frontier (For Publishers, Sales Houses, and SSPs)

• Independent Publishers:  Develop first-party data strategies. Invest in registration, graph building, and contextual models. Work with partners to understand your users across more signals so buyers can find the audiences they want inside your environment.
  
• Sales Houses & Monetization Wrappers:  Shift models toward first-party data and signaling. Use identity-resolution tools and wrappers that perform well without cookies. Consider curation as a scaled solution across your portfolio.
  
• SSPs:  Increase bidstream quality with publisher signals. Broaden your ID coverage to support traffic that arrives without cookies. Once IDs map to your graph, make sure each buyer receives the right identity currency. Most buyers still check for their preferred ID first, then fall back to enriched signals.