How Broad Should the Scope of Patent Protection Be?
探讨专利长度（保护期）与宽度（覆盖范围）之间的权衡，分析不同条件下哪种专利设计能更有效地激励创新并减少社会福利损失。
I explore 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. I show 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.