Ability to use GTIN and Brand/MPN as eBay Catalog Identifiers in the Description policy
When you specify a product from eBay catalog, eBay will use own product details that help more buyers find it. Ability to search products by GTIN, Brand/MPN is currently added in the Description policy.
Ability not to list product if it is not found in eBay Catalog
You can choose what eBay should do if no product match has been found according to the parameters specified in the eBay Catalog Identifier tab.