Concrete of the neighbor's L-stones in my garden

Hello everyone, my neighbor has laid L-shaped stones at the property boundary, whereby the foundation extends underground about 50cm into my property. Can I demand that this concrete on my side be removed again? Would the neighbor’s property still be stable then? At the front is the driveway, and at the back a garage is to be placed. I look forward to any advice. Thanks in advance.

He is not allowed to do that, that is clear. Whether his (the neighbor’s property) is still stable if the concrete on your side is removed is not your concern either. However, I would definitely seek a conversation and look for a solution that aligns with the wishes for YOUR property. If you pave your driveway there, you would need a solid base anyway. But if you want to create a flower bed there, the situation looks different again. Of course, it also depends on how your neighbor reacts to the issue. If he is reasonable, I would respond very differently than if he does not want to talk to you at all in this regard. 50cm (over a longer length) can indeed end up in court (if you want that), and I do not see a deconstruction as entirely unlikely. Please describe pictures and the overall situation in more detail ...

I would like to have your crystal ball.

That was an example of why one might have only noticed it now.

Apparently, everyone here always assumes that you build your house in a greenfield and stand there every day when the neighbor already starts to fence off his property.

Stick to your own know-it-all advice and don’t look into the crystal ball...

Even if a neighbor is currently building something.... you don’t necessarily watch their project with eagle eyes. Sure, if something happens right on the border, you can definitely take a peek – or just talk to the neighbors. Otherwise, you simply don’t notice it right away. You’re not there, it was already there before moving in, who knows. The border at our place was significantly built over, but about 30 years ago or so. We took note of it, talked to the neighbors, everything stays as it is and it works for everyone (back then there was a sort of exchange without a notary, here a piece from you, there a piece from you). If we had moved in without knowing, we would have been initially quite surprised. And such things are not unlikely.