Since 01.01.2017 all electronic cash registers used in Germany must be GDPdU / GoBD compliant. This means that the funds must comply with the "principles of proper accounting".
This means among other things:
Incomes and expenditures must be stored seperately
The data must be available at all times, immediately readable and machine-evaluable
Required documents such as manuals, work instructions, operating and programming instructions must be provided
Individual data including structural data must be made available in a format that can be read by the tax office
All data must be kept for 10 years (in electronic form, complete, without data compression)
The data in the cash register must be stored tamper-proof and unchangeable
Note: blue image GmbH must not provide advice on tax or legal issues. The information on this page does not claim to be complete and does not replace expert advice from a tax advisor or lawyer. Any liability is excluded. Please contact your tax advisor or lawyer if you require further information.