How long is the protection period of German patents?

German patents are divided into inventions, utility models and designs, which are stipulated by different laws. Their protection starts from the day after the patent application, but the term is different. The protection period of the invention is twenty years (Article 16 of the Invention Patent Law); The term of the utility model is three years, which can be extended for three years after the expiration, and can be extended for two years at a time, and can be extended to ten years at the longest (Article 23 of the Patent Law of Utility Models); The term of a design is five years, and it can be renewed many times after the expiration. It can be extended for five years at a time and up to twenty years at the longest (Article 9 of the Design Patent Law).