What Is an LOU (Local Operating Unit)?
When you register an LEI, the organisation that actually issues and maintains it is called an LOU — a Local Operating Unit. LOUs are the working engine of the Global LEI System.
The role of an LOU
An LOU is an organisation accredited by GLEIF to issue LEIs and keep their data current. Each accredited LOU is assigned its own four-character prefix — the first four characters of every LEI it issues — so codes from different LOUs can never collide.
The core job of an LOU is validation. Before an LEI is issued, the LOU checks the entity's legal details against an authoritative source, usually the relevant national business registry. This is what gives the LEI its credibility: the data behind it has been verified, not self-declared.
LOUs vs Registration Agents
The LOU is the accredited issuer; a Registration Agent is an intermediary that helps you reach an LOU and manages the paperwork, renewals and support on your behalf. TrustedLEI works as a Registration Agent, so you get a streamlined process and local-language service while your LEI is issued through an accredited LOU.
You're not locked in
Your LEI is portable. If you're unhappy with the service from the LOU currently maintaining your code, you can transfer it to another — the 20-character code itself never changes. (See How to transfer an LEI.)
See also What is GLEIF? and What is a Registration Agent?