Geographical patterns in US inventive activity 1977-1998: The “regional inversion” was underestimated

Towards the end of the previous century, the geography of US inventive activity changed drastically. The old hotbeds of invention (the Northeast and Midwest) lost much of their prominence, and rates of invention in Western states grew considerably. In this paper, we argue that this well-known “regional inversion” has been underestimated. We arrive at this conclusion by addressing an important concern regarding the use of raw patent counts in the previous literature: raw patent counts do not tell much about inventive performance, since the importance of patents in terms of their impact on future technological and economic developments varies much. We focus on “superstar” patents, which are disproportionally important. We identify these employing a statistical regularity in citation patterns. We find that the West did not only outpace the Northeast and Midwest in the numbers of patents produced, but also specialized much more in patents that “really matter”.