A required field for custom goods
This new attribute was created for shops that offer custom goods without an identifier like GTIN or MPN. Custom goods are hand knitted sweaters or antique furniture or vintage items. The ‘Identifier Exists’ field can be used to indicate that an identifier does not exist for certain products: Identifier exists = false.
Not required for regular goods
Everybody else, with ‘normal’ goods, will have to enter an identifier like GTIN or MPN. They do not have to add the “Identifier exists” field to their feed - when it is not provided, Google assumes that an identifier exists.
“Identifier exists” is not an easy way out for merchants that sell regular products but forgot to add an identifier to their feed. If an identifier for a given product does exist and ‘Identifier_exist’ field is set to ‘FALSE’ (so you are 'lying' to Google), that product can be banned.
How to add ‘identifier exists’ to your feed?
Let’s say that you sell both ‘custom’ and ‘normal’ products.
For the custom goods without an identifier, you need to add ‘identifier exists = false” because there is nothing in the fields for UPC (=GTIN).
This means that ‘identifier exists = true” for your normal products:
Is MPN or GTIN mandatory?
Yes, for most products you need to have at least 2 out of these 3 fields: Brand, MPN and GTIN, as long as you don’t sell custom goods. In the words of Google:
- Apparel categories: 'brand' is required. Additionally, for the categories listed below, you must submit at least 1 out of 'gtin' or 'mpn’:
- 'Apparel & Accessories > Shoes'
- 'Apparel & Accessories > Clothing Accesories > Sunglasses'
- 'Apparel & Accessories > Handbags, Wallets & Cases > Handbags'
- 'Apparel & Accessories > Jewelry > Watches'
- Media and software categories: 'gtin' is required
- All other categories: at least 2 of the following 3 identifiers are required: ‘brand’, ‘gtin’, and ‘mpn’.
- Exception: in categories where unique product identifiers are required but no such identifier exists for an item (e.g. custom goods), submit 'identifier exists' with a value of FALSE.
I don’t have MPN or GTIN but it does exist
That happens a lot. The best solution is to ask the manufacturers of your products for all MPNs or GTINs and add them to your shop. If that doesn't work, you’ll get away with mapping MPN from ID; then you’ll make the 2 out of 3, assuming that you do have brand. Read more about this in Brand, MPN and GTIN.