Research on the patent system and the analysis of patenting activities have become an important field in economics and l)usin(\ss administration. The global demand for patcuit protection has been increasing strongly over the last decades. Institutional changes as well as the broadening of patentable subject matter pose new challenges to patentees and patent offices alike. Especially in Europe, the debate on the patentabihty of biotechnology and softwa- related inventions led to broad public attention to the design of the patent system. Given these developments, it is no wonder that practitioners as well as policy makers are turning to researchers for answers on how to cope with new challenges threatening the patent system. In his dissertation, Stefan Wagner attempts to answer some of these questions. Wagner apphes advanced econometric methods to large-scale data sets which were assembled specifically for the purpose of this thesis. His analysis focuses on various aspects of patent filings, examination and opposition at the European Patent Office. Each of the four self-contained chapters of this book addresses different issues which are important to all stake-holders of the patent system. Wagner closely analyzes institutional features of the European Patent Office, such as the duration of the examination of patent applications, the determinants of the occurrence of patent oppositions and the patentability of business methods under the European Patent Convention. In his concluding chapter he examines the managerial decision between outsourcing patent-related services to patent attorneys or generating them in-house.