The Legal Entity Identifier is a 20-character code identifying a legally distinct entity participating in financial transactions, standardised as ISO 17442 and operated by GLEIF through accredited issuers. It exists because the 2008 crisis revealed that no one could reliably say which entity was counterparty to which exposure.
LEI
The LEI answers a question that sounds trivial and is not: which legal entity is this? Names are ambiguous, subsidiaries share them, and corporate structures change. The LEI gives an entity one identifier, with its parent relationships published alongside, and GLEIF makes the whole register available as open data.
- One code per legal entity - Twenty characters, issued once, maintained through annual renewal.
- Level 2 parent data - Direct and ultimate parents published, so ownership chains are traceable.
- Open reference data - The full register is downloadable and queryable — a public identifier registry, freely available.
- Mandated in reporting regimes - EU and US transaction reporting require it, which is what drove adoption.
- vLEI - A verifiable-credential form, aimed at machine-to-machine attestation of organisational identity.
The LEI belongs in any discussion of agentic commerce and compliance. The State of Legal & Compliance APIs finds a market with 928 distinct resource names and almost no shared vocabulary — matter at seven providers, clause at none. The LEI is the counter-example: one identifier, operated as a registry, published openly, adopted because a regulator required it. Registries that are run rather than certified keep producing the interoperability this research finds missing elsewhere.
Referenced in API Evangelist papers
This standard shows up in my published research. These reports read the machine-readable evidence provider by provider — and put this standard in the context of a real sector.
The State of Legal & Compliance APIs
One identifier per legal entity, operated as an open registry — the counter-example to a market with 928 resource names and almost no shared vocabulary.
