Germany allows dual citizenship only in exceptional cases. Generally, you have to renounce your current citizenship.
Do I have to renounce my original citizenship if I become a German citizen?
I want to make an investment in a business located in Berlin and use it to apply for a German resident permit. I know that if the business goes well, I can apply for permanent residency and ultimately German citizenship. Does Germany allow dual citizenship? Do I have to renounce my original citizenship?