What is a Business Rule (BR) in e-invoice?
Short answer
Business Rule (BR) is a validation rule that verifies whether the e-invoice meets the requirements of the EN 16931 standard or the relevant implementation (for example, Peppol BIS Billing or Slovak transpositions). Unlike XML Structure (XSD) validation, Business Rules validate business logic — data obligation, correctness of calculations, and permissible combinations of values. Violation of the business rule is the most common reason for e-invoice rejection during validation.
Not an XML element
BR verifies the logic and links between the data, not its technical notation.
BR-01, BR-CO-10, BR-S-08
Each rule has its own identifier visible in the validation report.
Verification mechanism
Business Rule is a rule, Schematron is a tool that executes it.
Not a business judgment
BR does not verify the existence of the delivery or the correctness of the tax regime.
Conclusion
Business Rule is a named validation rule verifying the logic and calculations of the e-invoice, performed via Schematron — its fulfillment is a necessary but not sufficient condition for the correctness of the invoice.
Not legal advice. Machine-translated answer, not yet manually reviewed. For the exact wording, see the Slovak original.