A financial identifier names an object within a specified identification scheme, such as a legal entity, an instrument or a market. Matching an identifier resolves only the object and relationship covered by that scheme and mapping.

Entities, instruments and markets

A Legal Entity Identifier, or LEI, identifies a legal entity. The Global LEI Index contains historical and current entity records and reference data. Parent-relationship information adds another relationship; it does not make an entity identifier a security identifier.

An International Securities Identification Number, or ISIN, identifies a financial instrument within its framework. A Financial Instrument Global Identifier, or FIGI, supports instrument identification and mapping. OpenFIGI maps FIGIs and other market identifiers; the mapping’s instrument and listing context still matters.

A Market Identifier Code, or MIC, identifies a market within the ISO 10383 framework. An instrument match does not select the venue on which an order should execute.

Take one issuer with two securities, one of which trades on two venues. The issuer identity alone selects neither the security nor its execution venue. Adding a security identifier resolves another object, but the intended route still needs a venue and the relevant trading context.

Identifier mappings in order routing

A routing instruction combines instrument identity with other information, including destination and permitted order behavior. If two applications exchange only a display symbol, the receiving application needs enough context to determine the intended instrument.

An identifier map therefore carries the scheme, mapped object, source and effective date. An ambiguous result needs an explicit resolution rule. Silently selecting one result turns a data ambiguity into an operational decision.

Mapping success is also narrower than trade authorization. Identifying the intended instrument does not establish the requester’s permission to trade it or the account’s available allowance.

Counterparty identity and historical relationships

A counterparty to a trade is a legal entity recorded in the transaction relationship. It need not be the issuer of the instrument being traded. Using issuer identity as the counterparty aggregation key would combine different economic relationships.

Historical analysis needs the mapping effective for the relevant time. A present-day parent relationship or instrument mapping cannot silently replace an earlier relationship in a historical record. Corporate actions and reference-data corrections require versioned mappings.

Scope of identifier evidence

An identifier establishes identity within its documented object and scheme. It does not independently establish beneficial ownership, account entitlement or enforceable netting.

What changes among identifiers is the object named and the mapping context. Typed fields, effective dates and provenance preserve those distinctions when orders, holdings and exposures cross application boundaries.

Questions about LEI

Does an LEI identify a security?

No. An LEI identifies a legal entity.

Does an instrument match identify the counterparty to a trade?

No. The counterparty is a separate legal entity and relationship in the trade record.