James Watt's 1769 patent is widely supposed to have stood in the way of the development of high-pressure steam technology until it finally expired in 1800. We dispute this popular claim. We show that, although it is true that high-pressure steam technology developed only after the expiration of...

Exclusive patents sacrifice product competition to provide firms incentives to innovate. We characterize an alternative mechanism whereby later inventors are allowed to share the patent if they discover within a certain time period of the first innovator. These runner-up patents may reduce the...

The “monopoly” authorized by the Patent Act refers to the exclusionary power of individual patents. That is not the same thing as the acquisition of individual patent rights into portfolios that dominate a market, something that the Patent Act never justifies and that the antitrust laws...