When Do Applicants Search for Prior Art?
There is concern that patent examiners lack the resources, capabilities, and incentives to properly identify the prior art against which patent applications are evaluated and that, as a result, they issue a large number of low-quality patents. In this context, the extent to which applicants have incentives to contribute prior art is an important question. This paper uses data on examiner and applicant citations in U.S. patents to examine this question. The data show that applicants contribute a surprisingly low share of citations to previous patents and routinely fail to identify even their own previous patents. However, there are also stark differences across fields. Within fields, and even within firms, there is self-sorting: applicants contribute more prior art for their more important inventions. The results suggest that incentives to search for prior art vary across industries and inventions, which reflects underlying differences in the strategic reasons for obtaining patent protection. (c) 2010 by The University of Chicago. All rights reserved.
References listed on IDEAS
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- Manuel Trajtenberg, 1990. "A Penny for Your Quotes: Patent Citations and the Value of Innovations," RAND Journal of Economics, The RAND Corporation, vol. 21(1), pages 172-187, Spring.
- Ricardo J. Caballero & Adam B. Jaffe, 1993.
"How High are the Giants' Shoulders: An Empirical Assessment of Knowledge Spillovers and Creative Destruction in a Model of Economic Growth,"
NBER Chapters,in: NBER Macroeconomics Annual 1993, Volume 8, pages 15-86
National Bureau of Economic Research, Inc.
- Ricardo J. Caballero & Adam B. Jaffe, 1993. "How High are the Giants' Shoulders: An Empirical Assessment of Knowledge Spillovers and Creative Destruction in a Model of Economic Growth," NBER Working Papers 4370, National Bureau of Economic Research, Inc.
- Lanjouw, Jean O & Pakes, Ariel & Putnam, Jonathan, 1998. "How to Count Patents and Value Intellectual Property: The Uses of Patent Renewal and Application Data," Journal of Industrial Economics, Wiley Blackwell, vol. 46(4), pages 405-432, December.
- Scherer, F. M. & Harhoff, Dietmar, 2000. "Technology policy for a world of skew-distributed outcomes," Research Policy, Elsevier, vol. 29(4-5), pages 559-566, April.
- Jean O. Lanjouw & Mark Schankerman, 2004. "Patent Quality and Research Productivity: Measuring Innovation with Multiple Indicators," Economic Journal, Royal Economic Society, vol. 114(495), pages 441-465, April. Full references (including those not matched with items on IDEAS)