Google's decision to maintain third-party cookies in Chrome does not eliminate the need for robust identity resolution. With 20 states now enforcing comprehensive privacy laws and 34.9% of US browsers already blocking third-party cookies by default, marketers must master consumer data collection and cross-channel identity to deliver personalized experiences and prove marketing effectiveness. This FAQ addresses identity resolution strategies across digital channels and the approaches winning brands deploy.

What is identity resolution and why does it matter for marketers?

Identity resolution connects disparate consumer data sources to create unified customer profiles. It enables marketers to accurately target messages, personalize campaigns, measure performance across channels, and deliver seamless customer experiences.

Identity resolution remains critical despite Google's cookie reversal. Consumer privacy concerns and expanding state-level regulations restrict data access. The mix of identifiers across display, retail media, digital out-of-home (DOOH), and audio channels demands sophisticated identity solutions for coherent cross-channel campaigns.

62% of brand marketers say first-party data will become more important over the next two years, per October 2024 data from Econsultancy. Marketers that want to connect consumer journeys across digital channels should invest in signal-agnostic identity solutions, minimizing disruption from additional regulation.

What types of consumer data should marketers collect for identity resolution?

Marketers must understand the distinct advantages and limitations of each data type:

• Zero-party data. Information consumers voluntarily provide through surveys, quizzes, preference centers, and feedback forms. Highest quality but limited scale.
• First-party data. Data collected directly through owned channels including website behavior, purchase history, email engagement, and app usage. Essential foundation for identity resolution.
• Second-party data. Another organization's first-party data acquired through direct partnerships. Expands reach while maintaining quality.
• Third-party data. Aggregated from various sources by providers without direct consumer relationships. Broader scale but less accurate.

Comprehensive customer profiles combine demographic data (age, gender, location), behavioral data (website visits, app usage), attitudinal data (survey responses, NPS scores), transactional data (purchase frequency, order value), and digital identifiers (IP addresses, device IDs, authenticated logins).

How is privacy legislation changing identity resolution?

Privacy regulations are reshaping data collection and use. Twenty states have enacted comprehensive data privacy laws, with eight new state laws taking effect in 2025 alone (Delaware, Iowa, Nebraska, New Hampshire, Tennessee, Minnesota, Maryland, and New Jersey). Indiana, Kentucky, and Rhode Island follow on January 1, 2026.

Each state creates unique compliance requirements restricting how marketers collect and activate consumer data. A federal privacy bill, the American Privacy Rights Act (APRA), was introduced in April 2024 to eliminate the state-by-state patchwork. The bill stalled in June 2024 when committee markup was canceled.

Digital privacy laws in 20 states contain provisions that directly implicate AI systems, covering automated profiling, behavioral advertising, and sensitive data processing, regardless of whether AI is explicitly named in the statutory text.

Why did Google abandon third-party cookie deprecation?

Google's April 2025 announcement reversed its cookie deprecation plans. Rather than prompting users to opt out of third-party cookies, Chrome will continue supporting them by default. Users can manually disable tracking, but most will not.

Then, in October 2025, Google officially scrapped its Privacy Sandbox, eliminating the final 10 Sandbox technologies that were still in place and effectively ending its yearslong plan to move away from third-party cookies.

Three factors forced Google's reversal:

• Regulatory pressure. The UK's Competition and Markets Authority raised serious concerns in their April 2024 report.
• Economic damage. Testing showed publishers would lose approximately 60% of Chrome revenue if cookies disappeared, far exceeding Google's 5% target.
• Industry opposition. The IAB Tech Lab warned Privacy Sandbox would restrict the digital media industry's ability to deliver relevant, effective advertising.

What identity solutions are available to marketers?

Identity solutions connect users across devices and environments using two data types:

• Deterministic data. Definitive identifiers like email addresses or phone numbers. Creates high-accuracy matches but limited scale. Much of this data lies within walled gardens.
• Probabilistic data. Temporary signals like IP addresses, device characteristics, and timestamps used to infer identities through statistical modeling. Enables broader scale with lower precision.

Universal IDs create privacy-compliant identifiers that persist across websites and devices. Key solutions include The Trade Desk's Unified ID 2.0 (UID2), which uses encrypted email addresses; ID5 ID, combining hashed emails, page URLs, and IP addresses; LiveRamp's RampID, transforming PII into persistent IDs; and Lotame's Panorama ID, linking behavior across web, mobile, and connected TV (CTV).

Non-ID solutions like Amazon Ad Relevance complement universal IDs for cookieless tracking, and cohort-based solutions that group users by interests rather than individual identities.

What are data clean rooms and how do they work?

Data clean rooms are secure environments where multiple parties share first-party data without exposing raw information. They add privacy protection while enabling audience insights and measurement.

66% of US data and ad professionals have adopted data clean rooms as a result of privacy legislation and signal loss, per February 2024 data from the IAB and BWG Strategy.

Retailers, brands, and media partners use data clean rooms to:

• Match purchase data with behavioral data. Combine datasets to target based on consumer psychology, behavioral patterns, and triggers.
• Connect online ads to in-store sales. CVS partnered with Pinterest to cross-reference Extra Care member purchasing habits with Pinterest data for closed-loop attribution.
• Inform future investments. Dentsu uses clean rooms to identify incrementality opportunities and advise clients on channel investment.

Amazon expanded Marketing Cloud clean room access to SMBs in September 2025, enabling smaller sellers to measure and optimize campaigns with enterprise-level sophistication.

How are users tracked across digital channels?

Tracking approaches vary by channel, each with distinct challenges:

Digital display exists between cookie-based measurement and future alternatives. Apple's AppTrackingTransparency impact has stabilized, and Google's cookie reversal provides temporary relief. Marketers should use this reprieve to strengthen first-party data capabilities and test identity solutions.

Retail media has grown rapidly as advertisers increasingly rely on retailers’ robust first-party data. However, the channel still faces major hurdles around standardization and measurement. US retail media will grow 19.4% to reach $58.79 billion in 2025, per EMARKETER's September 2025 forecast. The IAB and Media Rating Council released guidance in September 2023 to address fragmentation.

Digital out-of-home (DOOH) has solved basic exposure tracking but struggles with omnichannel integration. Programmatic will drive 30.3% of US DOOH spend in 2025, per an EMARKETER forecast requiring compatible measurement across channels.

Podcasts face the root problem of download-based delivery, making it difficult to verify ad exposure. EMARKETER forecasts 42.6% of Americans consumed podcasts in 2025, creating opportunity for streaming-first measurement solutions.

How should marketers approach identity resolution strategy?

Before implementing an identity solution, marketers should:

1. Identify organizational data gaps. Audit what consumer data you collect and where connections break across channels.
2. Evaluate solution fit. Match identity solutions to specific use cases. Universal IDs work for cross-site targeting; data clean rooms enable measurement and collaboration.
3. Secure leadership buy-in. Identity resolution requires investment. Winterberry Group reports $27 billion was spent in 2024 on data, data services, and data infrastructure in the US.
4. Test continuously. Many solutions remain in early stages; leave room for trial and error.
5. Prioritize privacy. Keep consumer privacy at the core of any identity solutions implemented.

Marketers that want to connect consumer journeys across channels should invest in signal-agnostic identity solutions to minimize disruption from future regulation.

We prepared this article with the assistance of generative AI tools and stand behind its accuracy, quality, and originality.

EMARKETER forecast data was current at publication and may have changed. EMARKETER clients have access to up-to-date forecast data. To explore EMARKETER solutions, click here.