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What is ePID? How can I obtain it and can I use it when listing items?
The ePID identifies a product within eBay catalogs. ePID is returned in the productSummaries.epid field of the Search in the Catalog API.
You can also find the ePID on eBay's Web site. When you search by keyword, search results will return matching products. ePID for the product can be seen once you click into the product.
Yes, you can use the ePID when listing items by passing it in the Item.ProductListingDetails.ProductReferenceID field. See attachment for sample AddItem request.