In order to apply the zero VAT rate to an intra-Community supply of goods, certain requirements have to be met. In particular, proof has to be provided that the supplying company, or the purchaser, has transported or dispatched the goods to another EU Member State. In principle, any permissible documents and means of evidence may be provided as proof. However, the German tax authorities impose very exacting standards on the documentary evidence requirement and will often refuse to grant a tax exemption in cases of even the slightest ambiguity. It is, therefore, advisable to provide the proof in the format specified in Section 17 of the German VAT Implementing Ordinance (Umsatzsteuer-Durchführungsverordnung, “UStDV”).
Invoice forms have to comply not only with tax regulations but also with civil law provisions given that, in principle, invoices are also business letters. This info sheet provides you with more information regarding the completeness of invoices.