An invoice line has no VAT category
Every invoice line (BG-25) must carry an invoiced item VAT category code (BT-151): it is what attaches the line to a line of the VAT breakdown.
Only the issuer holds this value: Factlint reports it and never fabricates it. Test your invoice to find out whether it is affected.
The message your validator prints
Copied verbatim from the sealed artefact: this is the exact sentence the check prints when this rule fails.
[BR-CO-04]-Each Invoice line (BG-25) shall be categorized with an Invoiced item VAT category code (BT-151).
Quoted from schematron-cen 1.3.16, licensed under EUPL-1.2.
Common searches around this code
These phrases mirror what an integrator searches for: code, syntax, rule, business field and correction.
Test your file with this error in mind
Upload the invoice involved: the report will say whether this code appears, where it appears in the document, and whether Factlint can only report it or also fix it.
To automate this check in an ERP flow, call the validation API and link every returned code to its public page.
Why this error happens
The omission almost always comes from a line added outside the normal path — shipping costs, a commercial discount, a comment line turned billable. The module that computes VAT does not see it: the breakdown stays consistent with itself while the line is attached to nothing.
How to fix it
Categorising a line is a tax decision: the code depends on the applicable regime, not on what the file contains. Add BT-151 to the reported line — its XPath is in the finding.
XML correction example
<ram:ApplicableTradeTax> <ram:TypeCode>VAT</ram:TypeCode> </ram:ApplicableTradeTax>
<ram:ApplicableTradeTax> <ram:TypeCode>VAT</ram:TypeCode> <ram:CategoryCode>S</ram:CategoryCode> </ram:ApplicableTradeTax>