LEI (Legel Entity Identifier) - ID

A Legal Entity Identifier (LEI) is a unique 20-character alphanumeric code used globally to identify legal entities that participate in financial transactions.

In the EU, LEIs are heavily mandated by regulations like MiFIR and EMIR to ensure market transparency and prevent financial fraud.

An example of an LEI belonging to a well-known European entity is:529900O1HZZDWNUT6Y94

This specific LEI belongs to ASML Holding N.V. (a major Dutch semiconductor manufacturer).

Structure of an LEI Number

Every valid LEI follows the ISO 17442 standard and is broken down into three logical parts:

• Characters 1–4 (Prefix): Identifies the Local Operating Unit (LOU) that issued the code.Example: 5299 indicates the LOU is the London Stock Exchange
• Characters 5–18 (Entity ID): A randomly generated, unique number assigned to the specific company. Example: 00O1HZZDWNUT6Y identifies ASML uniquely.
• Characters 19–20 (Checksum): Two digits used by computer systems to validate the code and prevent data entry errors

Multiple issuers exist, but the identifier is globally coordinated. LEI issuers are called Local Operating Units, or LOUs. An entity can choose an accredited issuer, not necessarily one in its own country, but the issued LEI is recorded in the Global LEI System and published through the GLEIF Global LEI Index. GLEIF describes the LEI as a unique 20-character code, and each LEI can represent only one entity.

An entity can transfer the management of its LEI from one issuer to another, for example for service or pricing reasons. That does not create a second LEI. It changes the managing LOU.

The LEI number does not change on transfer. The first four characters are indeed the LOU prefix, but they identify the LOU that first issued the LEI, not necessarily the LOU currently maintaining it. The LEI ROC explains that the prefix “identifies the LOU that first issued the LEI,” and adds that the entity may later have “ported the maintenance of its LEI to a different LOU.”

Sample LOU / LEI Issuer	Country / market association
London Stock Exchange LEI Limited	United Kingdom
Bloomberg Finance L.P.	United States
Ubisecure Oy / RapidLEI	Finland / global
GS1 AISBL	Belgium / global GS1 network
Kamer van Koophandel	Netherlands
INSEE	France
Bundesanzeiger Verlag GmbH	Germany
WM Datenservice	Germany
Krajowy Depozyt Papierów Wartościowych S.A.	Poland
CSD Prague	Czech Republic