Assuming you mean germany? In germany your company can not sue you for ownership of the software, but they can sue for all the earnings you made with it. I was

Assuming you mean germany? In germany your company can not sue you for ownership of the software, but they can sue for all the earnings you made with it. I was in a similar situation where I had an idea for a similar product the company I worked for was toying around but was not able to implement. In the end I quit, waited a few month and then implemented it, just to be sure.