A World Parts Manufacturer Identifier (WPMI) code is a code used to uniquely identify manufacturers of vehicle parts in the global automotive industry. It is defined by ISO 4100.
It is the parts manufacturer analogue to VIN's World Manufacturer Identifier. Unlike VIN numbers however, WPMI codes aren't intended to uniquely identify each part, merely to identify the manufacturer.
References
World Parts Manufacturer Identifier Wikipedia(Text) CC BY-SA