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A Product Registry is an IT system that serves as a repository for cross-mapping (aka anchoring) legacy Product Codes to codes which are shared across partners - Commodity Orderable, Product Catalog, Item.  A Product Registry also serves as a repository for other IT systems to be updated with the latest Product Catalogs. It fills a gap when there are many commodity classifications and product catalogs in use and when Global Trade Item Identifiers haven’t yet been universally adopted for all packaging.  Further it should serve as a stepping stone toward usage of GS1 and as a broker of GDSN master data to internal health IT systems.

SKU

aka Stock Keeping Unit

A SKU (Stock Keeping Unit), is an identifier used to distinguish and identify a product from others.  SKU's are usually alpha-numeric and are not created by the manufacturer.  Rather each merchant, warehouse, distributor, etc might create their own SKU.  SKU's are usually not useful outside of the organization that creates them.