We acknowledge financial support from the National Natural Science Foundation of China (no. 71603155, no. 71973032) and the MOE Project of Key Research Institute of Humanities and Social Sciences in Universities (no. 18JJD790003). All errors are our own. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research. NBER working papers are circulated for discussion and comment purposes. They have not been peer-reviewed or been subject to the review by the NBER Board of Directors that accompanies official NBER publications.

This study provides a growth-theoretic analysis of the effects of intellectual property rights on the takeoff of an economy from an era of stagnation to a state of sustained economic growth. We incorporate patent protection into a Schumpeterian growth model in which takeoff occurs when the population size crosses an endogenous threshold. We find that strengthening patent protection has contrasting effects on economic growth at different stages of development. Specifically, it leads to an earlier takeoff but also reduces economic growth in the long run. Keywords Intellectual property rights • Endogenous takeoff • Innovation • Economic growth JEL Classification O31 • O34 "England [...] by 1700 [...] had developed an efficient set of property rights embedded in the common law [and...] begun to protect private property in knowledge with its patent law. The stage was now set for the industrial revolution." North and Thomas (1973, p. 156

We explore the dynamic e¤ects of minimum wage in a Schumpeterian model with endogenous market structure and obtain the following results. First, raising the minimum wage decreases the employment of low-skill workers and increases the unemployment rate. Second, it decreases the level of output. Third, it decreases the transitional growth rate of output but does not a¤ect the steady-state growth rate. Our quantitative analysis shows that the magnitude of the negative e¤ects of minimum wage is sharply increasing in low-skill labor intensity in production and that employed low-skill workers gain initially but might su¤er from slower growth in future wages.

We explore how labor union a¤ects the wealth-income ratio in an innovation-driven growth model and …nd that it depends on the union's objective. If the union is employmentoriented (wage-oriented), then a decrease in its bargaining power would have a positive (an ambiguous) e¤ect on the wealth-income ratio. Calibrating the model to data, we …nd that a decrease in union bargaining power causes a sizable increase in the wealth-income ratio, which explains at least one-third of the increase in the US wealth-income ratio.JEL classi…cation: D31, J50, O30, O43