It’s not really possible to give specific advice without knowing which jurisdiction you’re in. In most European countries there are laws that govern employee inventions and grant a share of the profits of an invention to the employee (in Germany e.g. the Mitarbeitererfindungsgesetz). Besides advising you to talk to a lawyer - which people already did here - there’s really little to say without knowing more details. I…
Did you type out that entire German word without referring to Google?
Mitarbeiterer_findungs_gesetz : "employee invention law". Where Mitarbeiterer can be further broken into "mit arbeit -erer". Mit=with, arbeit=work, and -erer is a suffix also used in English for "person who does a thing".