(1) Patents have no effect in respect of a person who, at the time the application was filed, had already begun to use the invention in Germany or had made the necessary arrangements for so doing. That person is entitled to use the invention for the needs of their own business in their own workshops or in the workshops of others. This entitlement may be bequeathed or sold only together with the business. Where the applicant or the applicant’s legal predecessor has, before filing the application, disclosed the invention to others and, in so doing, has reserved his or her rights in the event of a patent being granted, a person learning of the invention as a result of this disclosure cannot invoke measures referred to in sentence 1 which they have taken within six months following disclosure.
(2) If the proprietor of a patent is entitled to a right of priority, the earlier application is decisive and not the application referred to in subsection (1). However, this does not apply to nationals of a foreign state which does not guarantee reciprocity in this respect if they claim priority of a foreign application.