4. Income Taxes (Details 1) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Loss before provision	€ 4,161	€ 4,165
United States
Loss before provision	3,147	3,093
Switzerland
Loss before provision	0	172
The Netherlands
Loss before provision	€ 1,014	€ 900

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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