Title: Patent claims and invalidity

Authors: Takashi Miyazawa, Hiroshi Osada

Addresses: Intellectual Property Division, Seiko Epson Corporation, 80 Hirooka, Harashinden, Shiojiri-shi, Nagano-ken 399-0785, Japan. ' Graduate School of Innovation Management, Tokyo Institute of Technology, 3-3-6 Shibaura, Minato-ku, Tokyo 108-0023, Japan

Abstract: A patent|s competitiveness is crucial in the enforcement of patent right to protect business and ensure profit. In the patent enforcement, disputes concerning invalidity have now become an inescapable issue. This study quantitatively analyses patents involved with post-grant oppositions filed in the Japan Patent Office. The total number of dependent claims is found to have significant positive correlation with the number of references listed in Japanese granted patent publications in the case of winning patents, but not in losing patents. The result indicates that it is crucial to utilise dependent claims according to the number of prior inventions and potential prior inventions in order to reduce the risk of the revocation and invalidation of a patent.

Keywords: private property; intellectual property; competitiveness; dependent claims; patent claims; post-grant oppositions; prior invention; winning patents; losing patents; patent right; patent enforcement; invalidity disputes; Japan; patent offices; positive correlation; references; patent revocation; patent invalidation; private law.

DOI: 10.1504/IJPL.2011.041065

International Journal of Private Law, 2011 Vol.4 No.3, pp.354 - 364

Published online: 28 Mar 2015 *

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