Licences
The Service is built with the following open-source components and official validation rule sets. They remain under their own licences (Terms of Use, section 14). We run them on our own servers and don't distribute copies. Where a licence also covers online access (the EUPL 1.2 for the EN 16931 rules below), we meet it by naming the licence and linking the source.
Open-source components
| Component | Author | Licence |
|---|---|---|
| Kotlin, kotlinx (serialization, coroutines and others), Ktor | JetBrains | Apache License 2.0 |
| Netty | The Netty Project | Apache License 2.0 |
| ph-ubl, ph-cii, ph-commons, ph-schematron, ph-xsd, phive, phive-rules | Philip Helger | Apache License 2.0 |
| Saxon-HE | Saxonica | Mozilla Public License 2.0 |
| SchXslt2 | David Maus | MIT License |
| Jakarta XML Binding, GlassFish JAXB, Eclipse Angus Activation | Eclipse Foundation | Eclipse Distribution License 1.0 |
| Logback | QOS.ch | Eclipse Public License 1.0 (dual-licensed; used under the EPL) |
| SLF4J | QOS.ch | MIT License |
| Okio, kaml, XML Resolver, jspecify and other small libraries | various | Apache License 2.0 |
Official validation rule sets
These rules are published by the bodies responsible for each format and used as published. We are not affiliated with or endorsed by them.
- EN 16931 validation artefacts — CEN/TC 434, European Union Public Licence (EUPL) 1.2 (licence text). Source code: github.com/ConnectingEurope/eInvoicing-EN16931.
- XRechnung Schematron and validator configuration — KoSIT (Koordinierungsstelle für IT-Standards), published at github.com/itplr-kosit, Apache License 2.0.
- Peppol BIS Billing 3.0 rules — the official Schematron rules maintained by OpenPeppol AISBL, published at docs.peppol.eu and used unmodified. OpenPeppol owns the specification and the rules. We are an independent implementation, not certified, endorsed or operated by OpenPeppol, and not a Peppol Access Point.