Patent databases for innovation studies: A comparative analysis of USPTO, EPO, JPO and KIPO

To help in the use of patent databases for innovation studies, this paper investigates the characteristics of four databases: the USPTO, EPO, JPO, and KIPO. For this purpose, all patents registered at each database over the three years 2008-2010 were extracted for cross-sectional analysis, and the number of annual patents registered in two patent classes, A61 and G06, during the last 20 years (1992 to 2011), was collected for longitudinal analysis. The analysis perspectives were set in the context of comparison between databases. After integrating the results of this comparison, this study summarized key features of each patent database in terms of the necessary conditions to be good knowledge sources of innovation studies. The research results are expected to contribute to a better understanding of the characteristics of various patent databases, and to further support the validity of patent analyses.