GTIN, MPN, and brand are identifiers, not fields to fill with guesses. An incorrect identifier can be more harmful than a missing value. Check what the manufacturer assigned and the specific item warning before editing a feed.
Official Google requirements
Google’s product data specification describes product attributes and notes that inaccurate or missing product information can cause disapprovals or display issues. Its identifier issue guide covers GTIN, MPN, and brand errors, including conflicting values. For MPN, Google says to use the manufacturer-assigned value and not create one yourself.
Practical checks
- Match the feed item to the exact product and variant on the storefront.
- Verify a GTIN against the manufacturer’s packaging or authoritative product record; preserve leading zeros.
- Use an MPN only when it is genuinely assigned by the manufacturer and is correct for that variant.
- Submit the actual brand associated with the product. Do not use “generic” or another filler value when it misstates the item.
- If an item genuinely has no applicable identifier, check Google’s current identifier_exists guidance for that product type before changing the attribute.
- Compare identifiers in the feed, product page, and any connected ecommerce integration.
Custom or handmade products can have different identifier handling; the applicable product data specification explains the conditions. Do not mark an item as custom merely to bypass an error.
Industry practice and our recommendation
Fix the source catalog or store integration, not just a one-time export, then verify a fresh feed run. Test representative variants and keep the original manufacturer data available. This is workflow advice; Google’s specification is the policy source.
See feed and product data support, review the website checklist, and use the FAQ.
Official sources
Product data specification · Fixing product data quality disapprovals
Related guide: Merchant Center price mismatch.