Which ZUGFeRD version do you generate?
We generate ZUGFeRD 2.5 / Factur-X 1.09. The latest published specification is ZUGFeRD 2.5.2 / Factur-X 1.09.2 of 4 August 2026. For recognition as an e-invoice, the BMF accepts ZUGFeRD from version 2.0.1 with XML that meets EN 16931.