This book describes the official patent grant procedure before the German Patent and Trade Mark Office and the European Patent Office and provides practical guidance to achieve a swift patent grant. If the patent grant is not successful, the patent office’s rejection decision can be challenged by a so-called “applicant’s appeal.” An existing third-party patent can be challenged within the opposition period through an opposition procedure. After the opposition period has expired, it is possible to request the invalidation of the third-party patent before the Federal Patent Court. Nullity appeal proceedings take place before the Federal Court of Justice in Karlsruhe. Additionally, there are official cancellation procedures against utility models, trademarks, and design rights. All these procedures before the DPMA (German Patent and Trade Mark Office), the EPO (European Patent Office), the BPatG (Federal Patent Court), the BGH (Federal Court of Justice), the EUIPO (European Union Intellectual Property Office), and the UPC (Unified Patent Court) are described in this book.