Working Papers

Episodes of booming innovation coincide with intense speculation in financial markets leading to bubbles — increases in market valuations and firm creation followed by a crash. We provide a framework reproducing these facts that makes a rich set of predictions on how speculation changes both the private and social values of innovation. We confirm the theory in the universe of U.S. patents issued from 1926 through 2010. Measures based on financial market information indicate that speculation increases the private value of innovation and reduces negative spillovers to competing firms. No commensurate change occurs in measures grounded in real outcomes.