Why do businesses such as fast-food restaurants, coffee shops, and hotels cluster? In the classic analysis of Hotelling, firms cluster to attract consumers who have travel costs. We present an alternative model where firms cluster because one firm is free riding on another firm's information...

Patents for several blockbuster biological products are expected to expire soon. The Food and Drug Administration is examining whether biologics can and should be treated like pharmaceuticals with regard to generics. In contrast with pharmaceuticals, which are manufactured through chemical...