Chain analysis
Also · Blockchain analysis · Chain surveillance · Pseudonymity
Chain analysis mines Bitcoin’s public ledger to cluster addresses, follow flows and attach identities, using heuristics and off-chain data such as KYC records.
Bitcoin is pseudonymous, not anonymous. Every transaction is public forever, and addresses are pseudonyms that can be linked. Chain analysis is the industry that does the linking. It groups addresses likely to share an owner, identifies change outputs, recognises wallet software by its patterns, and then attaches names using data from exchanges, merchants, leaks and subpoenas.
Its conclusions are probabilities, not proofs, and its heuristics can be wrong, which has not stopped them from being used in investigations and in blacklisting coins. Defences work by breaking the assumptions, avoiding address reuse, using coin control, CoinJoin or PayJoin, and above all limiting the off-chain data that ties a person to a wallet in the first place.
In French · Analyse de chaîne
