This paper explores a new dataset of transfers of patents recorded at the United States Patent and Trademark Office. The aim of the paper is twofold. First, a number of patterns are presented. For instance, the probability of a patent being traded monotonically decreases as a function of its age...

Classifying agents into subgroups in order to measure the plight of the "poor", "middle class" or "rich" is common place in economics, unfortunately the definition of class boundaries is contentious and beset with problems. Here a technique based on mixture models is proposed for surmounting...