What Is 33Across

Overview

33Across is a technology-driven advertising company that focuses on identity resolution and audience targeting in the digital ecosystem. It enables publishers and brands to identify users across devices and deliver personalized advertising experiences without relying on third-party cookies.

The company has evolved from a behavioral retargeting platform into a leader in privacy-conscious identity solutions. Its infrastructure supports real-time bidding, programmatic advertising, and data-driven marketing strategies across desktop, mobile, and connected TV platforms.

• Founded in 2006 by Mike Lindsay and Rob Carty, 33Across began as a behavioral targeting startup before pivoting to identity resolution.
• The company is headquartered in Seattle, Washington, with additional offices in New York and London to support global operations.
• 33Across powers over 1,000 publisher websites, including major media brands like Hearst, Condé Nast, and Cox Media Group.
• It reaches more than 150 million unique users monthly, making it one of the largest independent identity networks in the U.S.
• In 2018, 33Across launched its People-Based Marketplace, offering cookieless targeting using probabilistic and deterministic matching.

How It Works

33Across uses a combination of deterministic and probabilistic modeling to create persistent user identities across devices and sessions. Its technology integrates directly with publisher websites and ad tech platforms to enable targeted advertising without third-party cookies.

• Identity Graph: The system builds a unified view of users by linking anonymized logins, IP addresses, and device fingerprints across time and platforms.
• Probabilistic Matching: Algorithms analyze behavioral patterns such as typing speed, location, and browsing habits to estimate identity with over 85% accuracy.
• Deterministic Matching: Uses authenticated user data from publisher logins to confirm identity with near-100% certainty when available.
• People-Based Marketplace: Launched in 2018, this platform allows advertisers to target audiences based on verified user identities rather than cookies.
• Privacy Compliance: 33Across adheres to GDPR, CCPA, and IAB standards, ensuring opt-out mechanisms and data minimization in all operations.
• Programmatic Integration: The platform connects to major DSPs and SSPs, enabling real-time bidding using 33Across’s identity resolution layer.

Comparison at a Glance

Below is a comparison of 33Across with other identity resolution providers based on scale, technology, and market focus.

While 33Across has a smaller reach than some competitors, its focus on publisher partnerships and privacy-first design differentiates it in a crowded market. It avoids reliance on personal data and instead emphasizes anonymized, consent-based identity resolution, which aligns with evolving regulations and industry trends.

Why It Matters

As the digital advertising industry phases out third-party cookies, companies like 33Across play a crucial role in maintaining effective targeting while respecting user privacy. Its solutions help publishers monetize content and allow advertisers to reach relevant audiences in a compliant way.

• Enables cookieless targeting at scale, helping brands adapt to Chrome’s deprecation of third-party cookies by 2024.
• Increases publisher revenue by up to 30% through improved ad relevance and higher CPMs.
• Supports cross-device campaign measurement, allowing advertisers to track performance from desktop to mobile.
• Reduces reliance on walled gardens like Google and Facebook by offering an open, interoperable identity layer.
• Facilitates compliance with GDPR and CCPA through transparent data practices and user opt-out options.
• Partners with IAB Tech Lab on industry standards like the Ads.txt and Seller-defined Audiences initiatives.

With digital privacy regulations tightening and consumer expectations shifting, 33Across’s identity resolution model represents a sustainable path forward for open web advertising. Its blend of accuracy, scale, and compliance makes it a key player in the post-cookie era.