We compare the geographic location of patent citations to those of the cited patents, as evidence of the extent to which knowledge spillovers are geographically localized. We find that citations to U.S. patents are more likely to come from the U.S., and more likely to come from the same state...

We explore the use of patent citations to measure the "basicness" and appropriability of inventions. We propose that the basicness of research underlying an invention can be characterized by the nature of the previous patents cited by an invention; that the basicness of research outcomes relates...

This paper explores changes in university patenting behavior between 1965 and 1988. We show that university patents have increased 15-fold while real university research spending almost tripled. The causes of this increase are unclear, but may include increased focus on commercially relevant...

This paper is an attempt to quantify key aspects of innovations, 'basicness' and appropriability, and explore the linkages between them. We rely on detailed patent data. particularly on patent citations, thus awarding the proposed measures a very wide coverage. Relying on the prior that...

This paper explores the recent explosion in university patenting as a source of insight into the changing relationship between the university and the private sector. Before the mid-1980s, university patents were more highly cited, and were cited by more diverse patents, than a random sample of...

The authors compare the geographic location of patent citations with that of the cited patents as evidence of the extent to which knowledge spillovers are geographically localized. They find that citations to domestic patents are more likely to be domestic and more likely to come from the same...

We explore the usefulness of patent citations as a measure of the "importance" of a firm's patents, as indicated by the stock market valuation of the firm's intangible stock of knowledge. Using patents and citations for 1963--1995, we estimate Tobin's q equations on the ratios of R&D to assets...