Before changing your whole catalog, choose one affected variant. Save its Merchant Center item ID, the exact issue, the submitted identifier, and the Shopify variant it represents. Start with a reproducible example rather than a blanket setting.
1. The supplied GTIN is incorrect
A Global Trade Item Number (GTIN) identifies a trade item across sellers. Your internal stock keeping unit (SKU) serves a different purpose. Compare the submitted code with the manufacturer record for the exact size, color, and pack. Do not copy a similar item's identifier.
2. A GTIN exists, but you do not have it
Ask the supplier for the assigned code and variant mapping. Missing data in Shopify does not prove that no identifier exists. Do not use identifier_exists=false to hide a missing or incorrect assigned GTIN.
3. No GTIN was assigned
Some products genuinely have no GTIN. Brand and Manufacturer Part Number (MPN) may still identify them. Check the category-specific requirements. Use identifier_exists=false only when the required identifiers genuinely do not exist. Being handmade or own-brand does not settle that decision by itself.
4. Correct the source and verify the result
For the Google & YouTube channel, Shopify documents adding an assigned GTIN in the variant details and supplying brand and MPN where no GTIN exists. Check the integration that actually submits your catalog; other feed apps may map fields differently.
- Record the affected item ID, source variant, and corrected value in a small worksheet.
- After submission, compare the value received in Merchant Center with your source edit.
- Check whether the original issue clears. If an edit disappears after sync, identify which source replaces it.
Google describes 24 to 72 hours for relevant issue updates. That is processing guidance, not an approval promise. A saved Shopify edit does not establish that Google received it.
5. Keep eligibility separate from performance
An identifier fix can resolve an identifier issue. It does not establish that the product is serving or that its orders are profitable. Record those outcomes separately. You do not need another app just to begin this audit. If an agency controls your feed, share the affected-item worksheet with them.
Related guides
Product disapprovals: other common errors
Google Shopping for Shopify: the wider setup
Primary sources
Google: identifier_exists requirements
Google: correcting an incorrect identifier flag
Google: correcting an invalid GTIN
