What is Identity Resolution?

Identity resolution is the plumbing problem behind every signal-based selling strategy. A prospect visits your pricing page anonymously on their laptop. Three days later they download a whitepaper using a personal email. A week after that, a verified business email from the same person ends up in your CRM via SDR research. Identity resolution is the work of recognizing that all three events belong to the same human, and that human works at a company already on your target account list.

For GTM Engineers, identity resolution shows up in three layers. The first layer is website de-anonymization (RB2B, Warmly, Koala) that maps website visitor IPs and cookies to company records and sometimes individual contacts. The second layer is form-fill enrichment, where a partial form submission gets matched against your contact database to figure out who that person works for. The third layer is cross-channel stitching, where product usage in a tool like Mixpanel gets joined with CRM identity in HubSpot via a warehouse-side identity model.

RB2B popularized the simplest form of identity resolution for B2B GTM teams. Drop a script on your site, get a Slack notification with the name, title, and LinkedIn URL of every US-based business visitor on your pricing page. The match rate hovers around 15-25% for typical B2B sites, which is good enough to turn previously invisible traffic into a pipeline source.

The hard version of identity resolution lives in the data warehouse. Build a dbt model that joins Segment events, Stripe billing data, HubSpot contacts, and Marketo activity on a normalized email field, with fallback joins on cookie ID, IP plus user-agent, and company domain. Push the resolved identity back to operational tools through reverse ETL. This setup costs months of data engineering work and pays off when your product usage data needs to inform sales outreach with zero lag.

Quality varies dramatically by provider and method. Website de-anonymization tools that claim 50%+ match rates usually count company-level matches (we identified the company) as resolved identities. Person-level resolution, where you know the individual visitor by name, runs 10-20% even with good tools. Setting expectations correctly with sales leadership prevents the inevitable disappointment when "200 identified visitors" turns out to be "200 known companies with 30 named individuals."

Privacy regulation shapes identity resolution more than any other GTM data practice. GDPR in Europe and state-level laws like CCPA in the US restrict how much identifying data you can collect and process without consent. EU-only or EU-inclusive GTM motions should assume that cookie-based identity resolution carries legal risk unless you have explicit consent flows. US-only B2B operations have more latitude but should still document your data sources and retention policies before sales leadership starts pitching the practice externally.