This paper explores the patterns of citations among patents taken out by inventors in the U.S., the U.K., France, Germany and Japan. We find (1) patents assigned to the same firm are more likely to cite each other, and come sooner than other citations; (2) patents in the same patent class are...

This paper explores the patterns of citations among patents taken out by inventors in the U.S., the U.K., France, Germany and Japan. We find (1) patents assigned to the same firm are more likely to cite each other, and come sooner than other citations; (2) patents in the same patent class are...

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...

The goal is to tackle anew the main problems encountered in using patent data in economic research, namely, the large variance in the value of patents, and the difficulties in matching patents with economic categories. The first is addressed with the aid of patent citations, the second with...

This paper surveys the major changes in patent policy and practice that have occurred in the last two decades in the U.S., and reviews the existing analyses by economists that attempt to measure the impacts these changes have had on the processes of technological change. It also reviews the...

The goal is to tackle anew the main problems encountered in using patent data in economic research, namely, the large variance in the value of patents, and the difficulties in matching patents with economic categories. The first is addressed with the aid of patent citations, the second with...

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...