How do I fix "missing identifiers" warnings or disapprovals in my feed?
Quick Answer
Add GTIN, MPN, and brand attributes to your product feed. For custom products, use identifier_exists=false.
Understanding Product Identifiers
Google uses three main product identifiers to match your products to their database:
GTIN (Global Trade Item Number)
The barcode number on your product. Includes UPC (12 digits, North America), EAN (13 digits, Europe), JAN (Japan), ISBN (books).
Example: 012345678901
MPN (Manufacturer Part Number)
The unique code assigned by the manufacturer. Different from your internal SKU.
Example: ABC-1234-XL
Brand
The name of the product manufacturer or brand owner.
Example: Nike, Samsung, Apple
When Identifiers Are Required
Identifier requirements depend on your product type:
Identifiers Required
- All new products from recognized manufacturers
- Products with assigned GTINs (most retail products)
- Books (ISBN is the GTIN)
- Music and media with barcodes
Identifiers May Not Be Required
- Custom or handmade products
- Products made before GTINs existed (vintage items)
- One-of-a-kind items
- Store-brand or private-label products without assigned GTINs
- Parts and accessories from small manufacturers
When In Doubt
If a product has a GTIN assigned by the manufacturer, you should include it. Even if not strictly required, having identifiers improves your product matching and visibility.
How to Find Your Product GTINs
GTINs are assigned by manufacturers, not retailers. Here is where to find them:
Sources for GTINs
- Product packaging - The barcode number printed on the box
- Manufacturer documentation - Product sheets, catalogs, or spec documents
- Supplier data - Ask your supplier or distributor
- Manufacturer website - Often listed in product specifications
- GS1 databases - Official GTIN registries
Verifying GTINs
Before adding a GTIN to your feed, verify it is correct:
- Check the check digit is valid (last digit of the barcode)
- Confirm it matches the exact product variant (size, color, etc.)
- Search the GTIN online to see if it returns the correct product
Do Not Invent GTINs
Never make up GTIN numbers. Using invalid or incorrect GTINs will cause disapprovals and can result in account-level issues. If you do not have the real GTIN, use the identifier_exists attribute instead.
Adding Identifiers to Your Feed
Include identifiers in your product feed using these attributes:
Feed Attributes
| Attribute | Format |
|---|---|
| gtin | 8, 12, 13, or 14 digit number |
| mpn | Alphanumeric, max 70 characters |
| brand | Text, max 70 characters |
| identifier_exists | yes or no |
Example Feed Entry
mpn: ABC-1234-XL
brand: ExampleBrand
Using identifier_exists Correctly
When your products genuinely do not have standard identifiers, use the identifier_exists attribute.
When to Set identifier_exists to "no"
- Custom-made or handmade products
- Vintage items without modern barcodes
- Your own brand products without assigned GTINs
- Unique or one-of-a-kind items
When NOT to Use identifier_exists = "no"
- Products that have GTINs but you just do not have them
- Products from major manufacturers
- Standard retail products
Google Verifies This
Google checks if identifiers should exist for your products. Incorrectly claiming identifiers do not exist when they do can result in disapprovals and account issues.
Fixing Common Identifier Errors
Here is how to fix common identifier-related disapprovals:
"Missing value: GTIN"
Add the GTIN from your product packaging or manufacturer data. If it genuinely does not exist, set identifier_exists to "no".
"Invalid GTIN"
The GTIN format is wrong or the check digit is invalid. Verify the number from your product packaging.
"GTIN does not match product"
The GTIN you provided is for a different product. Each variant (size, color) needs its own unique GTIN.
"Identifier exists for this product"
Google believes this product should have identifiers. Find the correct GTIN or verify this is truly a custom product.
Best Practices
Follow these practices for identifier management:
Data Quality
- Collect GTINs when receiving products from suppliers
- Store identifiers in your product database
- Verify each GTIN is assigned to the correct variant
- Regularly audit your feed for identifier issues
When Launching New Products
- If creating your own products, consider registering for GTINs through GS1
- Include brand and MPN even if GTIN is not available
- Set identifier_exists correctly from the start
Feed Quality Check
Our scanner helps identify product data issues including missing identifiers and other feed problems that affect your Merchant Center performance.
Check Your Feed