Well... I guess my mother tongue came through lol... It´s called a double tax treaty (Doppelbesteuerungsabkommen) in Germany because it is supposed to stop a double taxation of the same income.

So, are you implying I cannot use a Form 8833 for this scenario at all? Sorry if that´s a dumb question but that´s what I was taught to do for rental income and some types of US retirement income that also gets taxed in Germany (taxpayer would be a US citizen / German resident in that case).

Thanks for your help!