How Broad Should the Scope of Patent Protection Be?

The author explores the trade-off between a patent's length (that is, its lifetime) and its width (that is, its scope of coverage). A wider patent generally reduces the distortion of consumers' choices between the patented brand of the product and unpatented, lower-priced varieties sold by competitors, but also permits higher prices, which increase (relative to profits) the deadweight losses from consumers switching consumption out of the product class. The author shows under what conditions infinitely lived, but very narrowly focused, patents are the socially efficient way to reward innovation and under what conditions very short-lived, but very broad, patents are optimal