mpn identifier Fix “Missing value [mpn]” on Google Merchant Center
Google requires MPN alongside brand when GTIN isn't available. Without either, the item can't be uniquely identified against the global product graph and gets rejected from Shopping placements.
What you see in Google Merchant Center:
Missing value [mpn]
API identifier: missing_required_attribute
MPN is the fallback identifier when GTIN isn't available. The pairing matters: MPN alone gets you most of the way, but channels prefer MPN + brand together. Without both, identification quality drops to roughly "we know it's a Sony product" rather than "we know it's the Sony WH-1000XM5".
For items with neither GTIN nor MPN, the identifier_exists: false declaration is the explicit answer. Bulk-setting that flag across the catalog to bypass MPN requirements is misuse and gets flagged in account-quality reviews.
The strategic context: catalogs heavy on resold products almost always have MPNs available — the manufacturer printed them. The work is sourcing rather than substituting.
Top causes
- 1
Item has no GTIN but the feed doesn't supply MPN as the fallback identifier
- 2
MPN exists in the source system but isn't mapped to the mpn field
- 3
Both GTIN and MPN are missing, with no identifier_exists: false flag
How to fix it
- 1
Identify affected items
Merchant Center → Needs attention → 'Missing value [mpn]'.
- 2
Source the manufacturer part number
Check the manufacturer's product page. Most branded products have an MPN even when the GTIN isn't in your system yet.
- 3
If genuinely no MPN, set identifier_exists: false
For custom-made, vintage, or own-brand products without manufacturer identifiers, identifier_exists: false tells Google to stop requiring them.
- 4
Update the feed and refresh
Force-fetch. Items clear within 15 minutes typically.
Related issues
Missing GTIN
Google Merchant Center reports this when a product is missing its GTIN (Global Trade Item Number) — the manufacturer-assigned barcode that uniquely identifies retail products. Affected items stop showing in Shopping ads, free listings, and Performance Max retail campaigns.
Read moreMissing brand
Google requires brand on items in most categories. Without it, Google can't disambiguate your product from similar listings by other sellers. Affected items are dropped from Shopping until brand is populated.
Read moreRelated fields
Related tools
FAQ
Do I need both GTIN and MPN?
GTIN alone is enough. MPN alone (with brand) is enough. Together is even better — Google's match rate improves with both. The blocking issue is when you have neither and don't flag identifier_exists: false.
Last reviewed: 26 May 2026
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