In any designated Contracting State a European patent application and a European patent shall have with regard to a national patent application and a national patent the same prior right effect as a national patent application and a national patent.

A national patent application and a national patent in a Contracting State shall have with regard to a European patent designating that Contracting State the same prior right effect as if the European patent were a national patent.

Any Contracting State may prescribe whether and on what terms an invention disclosed in both a European patent application or patent and a national application or patent having the same date of filing or, where priority is claimed, the same date of priority, may be protected simultaneously by both applications or patents.