The dynamics of the transfer and renewal of patents

"This paper explores the dynamics of the transfer of U.S. patents and the significance of the initial missallocation of patent property rights. Here we find that the initial missallocation of patent property rights is large and differs substantially across patentees and technology fields. We also find that the probability of a patent being traded depends on a number of factors - the age of the patent, the number of citations received by a given age, the patent generality and whether the patent has been previously traded or not. We will also analyze and interpret this new evidence using a theoretical model of patent transfers and renewal"--National Bureau of Economic Research web site