Tetsuo Wada is Professor of International Business at the Faculty of Economics, Gakushuin University, Tokyo, Japan. He obtained Ph.D. in Business Administration from the University of California, Berkeley, and LL.B. from the University of Tokyo. His research interest has been interdisciplinary since his dissertation by which US-Japan knowledge transfer was analyzed through transaction cost lens in relation to cross-licensing and joint venture activities. His recent focus has been placed on developing a novel large-scale data set of examiner citations used directly for rejections (X/Y-equivalent) out of the PAIR database of the USPTO in order to compare them with X/Y citations at the EPO and the JPO. This project has been conducted collaboratively with the Japan Patent Office, and also financially supported by the Research Institute of Science and Technology for Society (RISTEX), the Japan Science and Technology Agency.