TL;DR:
- Chainalysis published an ontology to standardize blockchain analysis and improve data quality in investigations.
- The initiative stems from the firm’s involvement in the case against Roman Sterlingov, creator of Bitcoin Fog, convicted of money laundering in 2024.
- The framework defines what it means for addresses to belong to the same cluster and separates fund tracing from end-user identification.
Chainalysis published a proposed ontology for blockchain analysis work, with the goal of establishing standards that allow investigators and prosecutors to rely on the soundness of the data they use in their cases. The proposal describes how to identify clusters of wallets and determine which ones might be under the control of a single entity.
Jacob Illum, chief scientist at Chainalysis, explained that the document seeks to answer a concrete question: what should an analysis tool do to be genuinely useful in an investigation. “What is supported by the data? That is my job, to tell an investigator everything they can do with what the data tells us,” Illum stated.
Not all blockchain analysis products are created equal.
Today we're launching something we believe the industry urgently needs: a formal ontology for blockchain address analysis and intelligence claims.
Here's why it matters 🧵 pic.twitter.com/Ag4AMkvGEQ
— Chainalysis (@chainalysis) June 29, 2026
The Bitcoin Fog Case Experience
The firm drew on its participation in the U.S. Department of Justice case against Roman Sterlingov, co-founder of the cryptocurrency mixing service Bitcoin Fog, to shape this proposal. During the trial, Judge Randolph Moss held a Daubert hearing to evaluate whether Chainalysis’s Reactor tool was sufficiently rigorous as expert evidence. The magistrate concluded that “substantial evidence supports the government’s assertion that the software is highly reliable,” which the company takes as a foundation for defending its methodology.
The ontology starts from the concept of “cluster” and acknowledges that the term “has no universal meaning in the industry“. To address this, it structures the analysis into two levels: the first defines the structural graph of relationships between addresses, and the second assesses the degree of confidence in that graph.
Chainalysis Sets the Limits of On-Chain Analysis
Illum was clear about what the tool cannot do on its own: identify the end user. Chainalysis can trace funds to an exchange or an entity that manages wallets on behalf of clients, but investigators would need to issue a court order to obtain the identity of the account holder. Fund tracing and identity attribution are, according to Illum, completely separate questions.
The proposal was published to spark a debate within the crypto industry. The firm has not yet actively sought formal feedback, beyond initial conversations with law enforcement groups. Illum warned that moving away from independent scrutiny of methodologies is “a clear red flag.”
