Under German law, the exemption from VAT for exports must be proven by means of receipts. For exports within the EU, according to section 6a, par. 1, no. 1 Value Added Tax Law, it links up with the fact that "the trader or customer has transported or dispatched the object of the supply into another EU member state".
These obligations to provide proof for VAT purposes within the Single European Market are subject to special challenges and there are no standard regulations within the EU. So, according to the law and starting from 01.10.2013, we as a German company need a documentary proof under section 17a Value Added Tax Implementing Ordinance, the so-called Entry Certificate.
By Entry Certificate, the fiscal authority understands a confirmation from the customer that the object of the supply has entered another EU member state.
Note, particularly for EU self-collectors of the goods es works Dürmentingen: In the event that we do not get an Entry Certificate from you, we will subsequently charge the German VAT of currently 19% on invoices issued.