diffusion play an important role in generating intertemporal spillovers (among others, Furman
and Stern, 2011; Williams, 2014). A central insight of this work is that control—both in the
form of physical exclusivity as well as in the form of formal intellectual property rights—over
tools and data can shape both the level and direction of innovative activity, and that rules and
institutions governing control over these areas has a powerful influence on the realized amount
and nature of innovation.