The authors thank Richard Sever, Joe Ross, and colleagues at the Cold Spring Harbor Laboratory for providing important institutional detail; and participants at the University of Hawai’i microeconomics brown bag, the National Bureau of Economic Research annual development meeting, the China Innovation and Entrepreneurship Seminar, Ohio State University, the Universite du Luxembourg, and the Growth Laboratory and TPRI workshops, as well as Andrew Foster and Patrick Gaulé, for helpful comments on the draft manuscript.