Indicators for Identifying Important Patents

Author Name GOTO Akira  (Faculty Fellow, RIETI / Professor, Research Center for Advanced Science and Technology, The University of Tokyo) /GEMBA Kiminori  (Shibaura Institute of Technology) /SUZUKI Jun  (Shibaura Institute of Technology) /TAMADA Schumpeter  (Faculty Fellow, RIETI / Assistant Professor, Institute of Business and Accounting, Kwansei Gakuin University)
Creation Date/NO. March 2006 06-J-018
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Research on innovation provides fundamental insights for productive discourse on science and technology policy. However, there has been little analysis conducted in Japan on the innovation indicators using patent statistics. The indicators typically used to date such as research and development investment amount and the simple count of number of patents. Apparently, there is a need for more sophisticated indicators.

This paper focuses on the importance of patents as a first step to construct more informative innovation indicator. We used Technology Trend Surveys published by the Japan Patent Office which select important patents using expert opinion, then considered possible indicators to identify important patents. The findings show that the number of citations received is effective as an indicator of the importance of patents, and that the number of inventors and the number of patents cited are also effective indicators. In the life sciences, however, the findings demonstrate that while the number of research papers cited (science linkage) in important patents tends to be high, a high science linkage does not necessarily serve as an indicator for identifying important patents.