GLEIF (The Global Legal Entity Identifier Foundation) is a non-profit international organization established in 2014. Its product is The Legal Entity Identifier (LEI), which is a unique internationally recognized company identification number. Apart from the LEI itself, GLEIF provides additional information about companies around the globe, such as registered address, principal place of business, country of incorporation, nature of business, and, to some extent, also ownership.
Such information can be a useful piece of data for KYC and client due diligence. The biggest advantage of GLEIF in AML/KYC context is its vast database of companies, where you can find the majority of legal entities incorporated anywhere in the world. It is, however, not recommended to rely solely on information available at the GLEIF website as in many cases, the data are outdated or generally wrong. While even the data in national commercial registers can be outdated, as GLEIF is an international non-profit organization, relying on its data could be seen as improper procedure, as typically the main source of KYC data should be governmental registries.
It does nevertheless serve as a great source of supporting information in case of any inconsistencies, and it can be used as a supporting source of information when applying the enhanced due diligence.
Source: https://www.gleif.org/en