Strategic Citation

Abstract

This paper investigates whether patent applicants strategically withhold citations to material prior art. Citation data suggest that applicants withhold between 21% and 33% of relevant citations. Variation in withholdings is explained by patent portfolio size and indicators of patent value. These data also highlight important differences across technology classes. In particular, firms are significantly less likely to withhold a citation when applying for chemical and drug patents. Robustness checks confirm that these results are not explained by inventor and attorney familiarity with citations, patent examiner heterogeneity, or the nationality of the inventor.

The nearly universal link between the age of past knowledge and tomorrow’s breakthroughs in science and technology: The hotspot

“…In patenting, the patent examiner’s official obligation is to augment authors’ citations by citing relevant work authors miss and minimizing irrelevant citations and strategic citations ( 21 ). Further, patent examiners assign references after seeing the submitted patent.…”

Lens or Prism? Patent Citations as a Measure of Knowledge Flows from Public Research

“…To date, however, we know surprisingly little about how well citations measure knowledge flows, though a number of studies provide grounds for skepticism (Jaffe et al 1998, Agrawal and Henderson 2002, Jaffe et al 2002, Duguet and MacGarvie 2005, Alcacer and Gittelman 2006, Alcacer et al 2009, Lampe 2011). Some of these studies note that patent citations might be noisy measures of knowledge flows (Jaffe, et al 1998, Agrawal and Henderson 2002, Jaffe, et al 2002), and others highlight the large share of citations contributed by patent examiners may not accurately reflect the knowledge used by the patenting firm (Alcacer and Gittelman 2006, Alcacer, et al 2009).…”

Prior art: To search or not to search

“…This feature of the model is not, however, in odds with empirical findings that more important patents include more prior art citations (suggesting perhaps more prior art search), see Sampat (2005) and Lampe (2008). Two of the parameters of the model, investment cost I and the value of a bad patent g, are likely to be related to the benefit from a valid innovation G. First, for the investment condition to hold, G needs to be high enough compared to the investment cost.…”

“…From 2001, the USPTO began indicating which prior art references were inserted by the examiner. This newly available data on prior art enabled empirical analysis of prior art (see, for example, the contributions in Sampat, 2005;Alcacer and Gittelman, 2006;Lampe, 2008;Alcacer and Gittelman, 2006;Alcacer et al, 2009).…”