Canadian Inventors of U.S. Patents: An Empirical Study for the Canadian Ministry of Innovation, Science and Economic Development

Abstract

In January 2016, the Canadian Ministry of Innovation, Science and Economic Development (the “Ministry”) commissioned this study to gain insight into technological innovation in Canada through the lens of the United States (“U.S.”) patent system. Comprehensive patent data of the sort required to make direct measurements of the Canadian patent system is not yet available in a form that lends itself to direct analysis, in particular patent data and metadata available as bulk downloads. In lieu of this, we use two massive data sets that we have assembled: (1) a dataset containing detailed information about patent prosecution in the U.S. from 1976 to the present, and (2) a dataset containing all federal U.S. patent litigations from 2000 to 2014 that resulted in a published opinion or order. We parsed these two datasets to derive a data subset containing all U.S. patents having at least one Canadian inventor (“Canadian-Contribution” or “CanCon” patents). The detailed information in the CanCon data subset has allowed direct analysis of such variables as inventor nationality (e.g., Canadian), numbers of inventors, application and issuance years, technology areas, assignees, prosecuting United States Patent and Trademark Office (“USPTO”) examiners, prosecuting attorneys, and/or prosecuting law firms. We constructed a comprehensive patent citation graph of all post-1975 patents, and used this graph to determine patent importance within this network using eigenfactor centrality methods. The results of our analyses offer new insights into the inventive behavior of Canadians and owners of patents that co-invent with Canadians. For example, in total there are 170,067 U.S. patents having at least one Canadian inventor. The mean importance of these patents is 1.133, which means that CanCon patents are, on average, 13% more important than the mean importance for all U.S. patents, which is 1.00. By comparison, the mean importance of all U.S. patents having at least one foreign inventor is 0.95, or of slightly below average importance. The technological fields having the largest numbers of CanCon patents tend to involve telecommunications, computers and computer software, pharmaceuticals, molecular biology, chemistry, land vehicles, and the design of furnishings. With respect to patents litigated in U.S. federal courts, CanCon patents are less likely to be the subject of a federal lawsuit, and, those CanCon patents that are litigated tend to be of lower importance than the average for litigated patents.