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UBL

UBL is an OASIS standard defining royalty-free XML schemas for the common documents of trade — order, despatch advice, receipt advice, invoice, credit note and dozens more — providing the shared document model that Peppol and several national e-invoicing regimes profile.

UBL is the OASIS-governed library of XML schemas for the documents businesses actually exchange — orders, despatch advices, receipt advices, invoices, credit notes, statements, catalogues. It is published royalty-free and standardized as ISO/IEC 19845.

  • A document library, not a protocol - UBL says what an invoice contains; it says nothing about how it travels. Peppol supplies the network.
  • Profiled in practice - Raw UBL is permissive, so real deployments constrain it: Peppol BIS, EN 16931 for European e-invoicing, and national variants.
  • Modelled on real trade - The document set follows the buy-ship-pay progression that UN/CEFACT also models.
  • Widely mandated - Several national e-invoicing regimes require a UBL-derived format.

UBL is a useful counterexample to the assumption that these markets lack semantics. The trade document model is fully specified, freely available, internationally standardized and two decades old. What The State of Supply Chain APIs found missing is not the model — it is any provider exposing it as something a machine can query rather than a file it can receive.

Industry: Trade

Also in the data model catalog

This standard shows up on both sides of the house — as a standard applied in API operations here, and as a data model defining what information exists. Same standard, two lenses.

See it as a data model →