When to set identifier_exists to no in Merchant Center

Set identifier_exists to no only when a product has no GTIN, MPN or brand assigned, such as handmade or one-of-a-kind goods. Where identifiers exist, submit them. Using the flag to skip a supplier lookup is a shortcut that comes back as a warning.

Major4 min read

By Edvinas Ivanauskas How the guides are reviewed

You run this check yourself

Our scanner can’t see inside your Google accounts, so this one’s on you. Work through the checklist below without running a scan.

How do I use identifier_exists in Google Merchant Center?

Set it to no in Merchant Center only when the product has no GTIN, MPN or brand assigned. Not because the supplier lookup is a pain. Google’s “Identifier exists [identifier_exists]” page says to submit no or false only if you’re certain the product doesn’t have any assigned unique product identifiers, and that products wrongly set to no, where there is evidence an identifier exists, will receive a warning. It names who qualifies: custom or one-of-a-kind goods such as handmade pieces, and products made before GTINs existed, such as vintage items and antiques. Anything made for general sale usually has a GTIN on the packaging: submit it with the brand and MPN. If a product has identifiers you don’t have yet, Google’s unique product identifiers page says to leave the attribute blank rather than stuff it with internal SKUs or borrowed numbers; that is not the same as declaring none exist. For a store brand, Google’s GTIN page says it generally won’t have a GTIN, so submit brand and MPN.

Why this matters

Google's “Identifier exists [identifier_exists]” page gives the attribute one job: to “indicate that unique product identifiers (UPIs) aren’t available for your product.” It asks you to submit no or false only “if you're certain that your product doesn’t have any assigned unique product identifiers”, and says that products where the value “is incorrectly set to no [no] or false [false] and for which there is evidence that a unique product identifier exists, will receive a warning”.

Who really has no identifiers? The same page names “Custom goods or one-of-a-kind products, like custom T-shirts, art, or handmade goods” and “Products produced before GTINs were introduced, like vintage products, antiques, books published before 1970, and other special products.” A product made by someone else for general sale usually carries a GTIN on its packaging, and Google's “About unique product identifiers” page is plain about what not to do: “Don't make up, guess, or include values from similar products.”

The middle ground is where stores slip. If a product has identifiers but you do not have them to hand, the same page says: “Leave the attribute blank - don’t include incorrect identifiers (for example, internal SKUs or other values specific to your store)”. That is not the same as declaring none exist. Store brands are covered on the “GTIN [gtin]” page: “If you’re the only seller of a product or if your product is a store brand, it generally won’t have a GTIN, so you don’t need to submit one.” If you make the product yourself with no official brand, Google's advice is to use your store name as the brand with an MPN of your own. For the brand field itself, see brand attribute mistakes.

Supplier records are checked manually: StoreVerifier does not see your product data. The free scan looks at the product page’s structured data instead. It flags a GTIN with the wrong length or check digit, and a product page whose structured data carries no GTIN or MPN. Identifier checks are listed with the others on the misrepresentation checker.

Typical evidence

When to use identifier_exists: no

Only use this flag when no manufacturer GTIN genuinely exists. For branded products with barcodes, submit the GTIN. Using identifier_exists: no to avoid it is a data integrity flag.

Does this product have a manufacturer's barcode (GTIN / EAN)?

YES → submit the GTIN

Find the number on the product packaging or in the GS1 registry. Submit it as the gtin attribute. Do NOT use identifier_exists: no.

NO → identifier_exists: no

Handmade, custom, or truly unbranded items with no manufacturer. Set identifier_exists: no explicitly — do not leave the gtin field blank.

Is this an assembled bundle or multipack without its own GS1 barcode?

YES → identifier_exists: no + bundle: yes

The bundle as assembled has no registered GS1 identifier. Mark as no + bundle: yes. Never use the component's GTIN for the whole bundle.

NO → submit the individual GTINs

If the bundle was produced as a unit by the manufacturer with its own barcode, submit that GTIN.

The GS1 database is publicly searchable. If a branded product has a registered GTIN, verify the submitted identifier before you publish it.

The public signals this check looks for:

identifier_exists set to no across the whole catalogue because it made a warning go away
identifier_exists set to no across the whole catalogue because it made a warning go away.
Branded products bought from a wholesaler sent without GTINs because the supplier sheet di…
Branded products bought from a wholesaler sent without GTINs because the supplier sheet did not list them.
Internal SKUs pasted into the [gtin] or [mpn] field
Internal SKUs pasted into the [gtin] or [mpn] field.
One GTIN reused for every size and colour of a product
One GTIN reused for every size and colour of a product.
A made-up or placeholder GTIN, such as a run of zeros, in a product page’s structured data…
A made-up or placeholder GTIN, such as a run of zeros, in a product page’s structured data.

What it looks like once it is right

The shop copies the EAN from each box, submits GTIN, brand and MPN for the kettles, and keeps identifier_exists as no only for its handmade tea towels, which carry the store name as brand and the shop’s own MPNs.

Common mistakes

Common mistake

A homeware shop resells branded kettles and sets identifier_exists to no on every item because its supplier sheet had no barcodes. The same kettles carry a 13-digit EAN on the box.

Self-check steps

Split your catalogue in two: products you make or that are one of a kind, and products someone else manufactures.
For manufactured products, take the GTIN from the packaging barcode or your supplier, with the brand and MPN, and submit all three where you have them.
Give each variant its own GTIN; the “GTIN [gtin]” page says each colour and size of a product has its own.
Where a product has identifiers you cannot get yet, leave the fields empty rather than filling them with SKUs or numbers from similar products.
Set identifier_exists to no only for custom, handmade, one-of-a-kind or pre-GTIN products, and submit the value in English, as Google's page notes.
For your own products with no official brand, use your store name as the brand and an MPN of your choosing.
Match the page: put the same GTIN, brand and MPN in the product page’s Product structured data, or identifierExists set to false where none exist.
After the next upload, check the Needs attention tab in Merchant Center for identifier warnings.

Three products — correct identifier handling for each

The rule is: if a GTIN exists, submit it. If no GTIN exists, submit identifier_exists: no. Never use identifier_exists: no as a substitute for submitting a GTIN you have.

Sony WH-1000XM5

Has GTIN: Yes (barcode on box)

GTIN: 4548736121201

Feed submits: gtin: 4548736121201

Handmade ceramic mug

Has GTIN: No (custom made)

Feed submits: identifier_exists: no

Generic earbuds (branded packaging)

Has GTIN: Yes (has a barcode)

GTIN: unknown (not looked up)

Feed submits: identifier_exists: no ← WRONG

For the generic earbuds: scan the barcode with any barcode scanner app to get the GTIN number, then verify it at gs1.org. If the number is registered, submit it. 'I did not look it up' is not a valid reason for identifier_exists: no.

Copy this, and change the parts in your own words

<g:identifier_exists>no</g:identifier_exists>

Questions merchants ask

When should I set identifier_exists to no?

When the product has no GTIN, MPN or brand assigned: custom goods, one-of-a-kind or handmade products, and items made before GTINs existed, such as vintage goods and antiques. Google asks you to submit no or false only if you are certain the product has no assigned unique product identifiers.

What if my supplier does not give me GTINs?

Ask for them or read them off the packaging. If the product has identifiers but you do not have them yet, Google's unique product identifiers page says to leave the attribute blank rather than fill it with internal SKUs or values from similar products. That is different from declaring that no identifier exists.

Do I need a GTIN for my own brand products?

Usually not. Google's GTIN page says that if you are the only seller of a product or it is a store brand, it generally won’t have a GTIN. Submit the brand and an MPN instead; if you make the product with no official brand, use your store name as the brand.

Remediation

Risk signal

identifier_exists is a statement about the product, not a switch for missing homework. Say a product has no identifiers when that is true, submit the real ones when it is not, and keep made-up numbers out of both the data and the page.

PriorityAddress and document this finding as part of the store’s remediation work.

EvidenceRecord the current state before each change, apply the fix, then capture the corrected state so every change is evidenced.

Similar cases

Sources

Last reviewed 23 Sep 2026.

That is one issue. The library documents 134.

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