Changes in University Patent Quality after the Bayh-Dole Act : A Re-Examination

The Bayh-Dole Act of 1980 facilitated the retention by universities of patent rights resulting from government funded academic research, thus encouraging university entry into patenting and licensing. Though the Act is widely recognized to be a major change in federal policy towards academic research, surprisingly little empirical analysis has been directed at assessing its impacts on the academy and on university-industry research relationships. An important exception is the work of Henderson et al. [Rev. Econ. Stat. 80 (1998) 119-127] which examined the impact of Bayh-Dole on the quality of university patents, as measured by the number of times they are cited in subsequent patents. The authors found that the quality of academic patents declined dramatically after Bayh-Dole, a finding that has potentiallyimportant policy implications. Inthis paper, we revisit this influential finding. By using a longer stream of patent citations data, we show that the results of the Henderson et al. study reflect changes in the intertemporal distribution of citations to university patents, rather than a significant change in the total number of citations these patents eventually receive. This has important implications not only for the evaluation of Bayh-Dole, but also for future research using patent citations as economic indicators