Traditional analyses of patent system have considered innovations in isolation and precluded the technological interrelationships between innovations. Common feature of cumulativeness during the process of technological change, however, brings the scope of patent protection into the major policy concern and currently occupies the central position in recent patent reform controversy. This study surveys the recent developments in the economic analysis of patent scope with corresponding introduction to the legal perspectives regarding patent scope. Although the issue of patent scope is complex in nature and depends crucially upon technological environment and the nature of innovations, this study can enlarge the understanding of the pros and cons of patent scope policy, which will become increasingly disputable in the forth-coming era of specialized patent court in Korea.