Selling products through Google Shopping feeds requires a valid product identifier so that the right product reaches the right costumer. Data files submitted to Google Shopping with invalid product identifiers are not processed. As a result for most categories you must add a product identifier, in other words an international code, the GTIN.

Google recommends providing clear product identification, as this helps to match offers to products, and to match products to relevant search queries. You can improve Google's understanding of products by using unique product identifiers like Global Trade Item Number. It is worth mentioning that products matched with Google inventory show a 40% increase on clicks in comparison with others. This enhances the dynamic of advertising and viewings on more sites, together with the correct and valid information on all available products, it improves online and mobile searches.

Since 2015 Google requires that all products destined for the markets of Australia, Brazil, Czeck Republic, France, Germany, Italy, Japan, The Netherlands, Spain, Switzerland, United Kingdom, U.S.A and more to be accompanied by valid GTINs and GS1 barcodes along with the brand for all new products. Products that do not comply with the guidelines above are not acceptable.