Pioneering Inventors or Thicket Builders: Which U.S. Firms Use Continuations in Patenting?
Why do firms use continuations in the prosecution of their patents? Motivated by the widespread use of continuations by U.S. firms and the prominence of this procedure in U.S. patent policy debates, we investigate the influence of corporate and patent characteristics on the use of continuations. We employ novel data on applicants and their filings of three types of continuations--the continuation application (CAP), the continuations in part (CIP), and divisions--during 1981-2000 to distinguish among the motives for continuing patents. We find that CIPs are disproportionately filed by research and development-intensive firms that patent heavily, and that these continuations are more common in chemical and biological technologies. Patents issuing from CIPs cover relatively important inventions and their use appears consistent with a strategy of protecting "pioneering inventions." In contrast, CAPs and divisions are associated with less important patents assigned to capital-intensive firms, particularly in computer and semiconductor fields, and appear to be used in defensive patenting strategies. We analyze the effects of the 1995 change in patent term, and find that the act reduced continuations overall and shifted the output of continuations toward less important patents.
Volume (Year): 55 (2009)
Issue (Month): 7 (July)
|Contact details of provider:|| Postal: 7240 Parkway Drive, Suite 300, Hanover, MD 21076 USA|
Web page: http://www.informs.org/
More information through EDIRC
Please report citation or reference errors to , or , if you are the registered author of the cited work, log in to your RePEc Author Service profile, click on "citations" and make appropriate adjustments.:
- Bronwyn H. Hall, 2005.
"Exploring the Patent Explosion,"
The Journal of Technology Transfer,
Springer, vol. 30(2_2), pages 35-48, January.
- Bronwyn H. Hall, 2004. "Exploring the Patent Explosion," NBER Working Papers 10605, National Bureau of Economic Research, Inc.
- Bronwyn Hall, 2004. "Exploring the patent explosion," Working Papers wp291, Centre for Business Research, University of Cambridge.
- Adam B. Jaffe & Manuel Trajtenberg & Rebecca Henderson, 1993. "Geographic Localization of Knowledge Spillovers as Evidenced by Patent Citations," The Quarterly Journal of Economics, Oxford University Press, vol. 108(3), pages 577-598.
- Adam B. Jaffe & Manuel Trajtenberg & Rebecca Henderson, 1992. "Geographic Localization of Knowledge Spillovers as Evidenced by Patent Citations," NBER Working Papers 3993, National Bureau of Economic Research, Inc.
- Jaffe, A.B. & Trajtenberg, M., 1992. "Geographic Localization of Knowledge Spillovers as Evidenced by Patent Citations," Papers 14-92, Tel Aviv.
- Simon Cheng & J. Scott Long, 2007. "Testing for IIA in the Multinomial Logit Model," Sociological Methods & Research, , vol. 35(4), pages 583-600, May.
- Stuart Graham & David Mowrey, 2004. "Submarines in software? continuations in US software patenting in the 1980s and 1990s," Economics of Innovation and New Technology, Taylor & Francis Journals, vol. 13(5), pages 443-456.
- Richard C. Levin & Alvin K. Klevorick & Richard R. Nelson & Sidney G. Winter, 1987. "Appropriating the Returns from Industrial Research and Development," Brookings Papers on Economic Activity, Economic Studies Program, The Brookings Institution, vol. 18(3), pages 783-832.
- Kenneth L. Sokoloff & Naomi R. Lamoreaux, 2001. "Market Trade in Patents and the Rise of a Class of Specialized Inventors in the 19th-Century United States," American Economic Review, American Economic Association, vol. 91(2), pages 39-44, May. Full references (including those not matched with items on IDEAS)