Taking works off copyright promotes their availability, but it also allows generic entry to dissipate producer surplus. This paper examines the effect of a copyright on the availability and price of books when incentives to create new works are not affected. Evaluating the welfare impact of the 1998 Copyright Term Extension Act, I find that a copyright significantly limits the availability of works, leading to a decrease in consumer surplus, which is significantly larger than any increases in profits to copyright holders. Without changing incentives to create new content, the copyright extension was economically inefficient.