How to fix: Limited performance due to missing identifiers: GTIN, MPN, brand

One or more unique product identifiers are missing or invalid, reducing the product's visibility on Shopping surfaces.

Product identifiers (GTIN, MPN, brand) anchor Google's matching of your product to its catalog. Issues here typically come from non-numeric characters in GTIN, mismatched UPC vs EAN length, brand-GTIN ownership conflicts in GS1's database, or duplicate GTINs across multiple SKUs.

1. Verify the GTIN ownership using GS1 GEPIR — confirms which brand legitimately owns the code (https://gepir.gs1.org).
2. Strip all non-numeric characters from GTIN values: no dashes, no letters, no spaces.
3. UPC = 12 digits, EAN-13 = 13 digits, ISBN-13 = 13 digits starting with 978/979.
4. If the product is private-label without a real GTIN, request a GTIN exemption rather than fabricating one.
5. Re-upload your corrected feed; new identifiers take 24–72 hours to propagate.

• Buying GTINs from non-GS1 resellers — they map to defunct brands and trigger validation failures
• Reusing the same GTIN across multipack and single-unit variants — Google flags duplicates