Hello.
 
I want to open a sole proprietorship. The flat where my family and I live is registered in my wife's name (we are married). However, now (I don't know from when), when registering the sole proprietorship, I have to present my wife's permission to register a company at this address. The permission or declaration has to be certified (it can be at the municipality, where it is free of charge, but it is an unnecessary complication). I could understand if they were not married or lived at different addresses, but I don't understand it like that. In the past, this has not been necessary.