Why we refuse to invent GTINs
Every listing tool faces the same request eventually: the marketplace wants a GTIN, the seller does not have one, and generating something that passes the check would make the problem go away. MergeKart will not do it, and the reason is worth setting out because it is not squeamishness — it is that the fabricated identifier causes a worse failure later.
A GTIN is a claim about identity, not a format
A GTIN is a globally unique reference to a specific product, issued through GS1 and resolvable to a manufacturer. A string that satisfies the check-digit arithmetic is not a GTIN; it is a number shaped like one. Validation checks the shape, so a fabricated value passes — which is exactly what makes it dangerous, because nothing fails at the moment the mistake is made.
What actually goes wrong: collisions
Marketplaces use identifiers to join listings to catalogue entries. A fabricated number that happens to belong to a real product attaches your listing to someone else’s catalogue record. Your item inherits their title, images and reviews, or yours are absorbed into their page. Untangling that is slow, and the marketplace treats it as your error.
The account risk is not theoretical
Marketplaces treat invented identifiers as catalogue abuse. Enforcement ranges from listing removal to selling-privilege suspension, and the appeal is difficult because the evidence is unambiguous: the identifier does not resolve to you.
There is a legitimate path, and it is not hidden
Where a product genuinely has no identifier — handmade, vintage, a bundle you assembled, an own-brand line — marketplaces provide exemption routes. Applying for one is ordinary, supported and usually quick. The exemption exists precisely because the honest case is common; the only reason to avoid it is impatience.
What MergeKart does instead
Where a required identifier is missing, the draft shows it as a gap pinned at the top and publish stays disabled until it is resolved. That is deliberately more friction than generating a number. The friction is the point: it surfaces a decision that is yours to make, rather than making it silently on your behalf.
The general rule
Anything a machine cannot determine is shown as a gap, never guessed. A missing value costs you a few minutes. A confidently wrong one costs you the listing, and sometimes the account.