Under continual innovation, greater patent strength expands innovating firms’ profit against imitation, but also shifts profit from current to past innovators. We show how the impact of patents on innovation, as determined by these two opposing effects, varies with industry characteristics....

This study develops a Schumpeterian growth model to analyze the effects of different patent instruments on innovation. We first analyze patent breadth that captures the traditional positive effect of patent rights on innovation. Then, we consider a profit-division rule between entrants and...