Software platforms are the invisible engines that have created, touched, or transformed nearly every major industry for the past quarter century. They power everything from mobile phones and automobile navigation systems to search engines and web portals. They have been the source of enormous...

Software platforms are the invisible engines that have created, touched, or transformed nearly every major industry for the past quarter century. They power everything from mobile phones and automobile navigation systems to search engines and web portals. They have been the source of enormous...

Many regulations impose lighter requirements on smaller firms than on larger firms. Such differential treatment is known as tiering. This article presents a framework for analyzing tiering. It assumes that regulators use taxes to reduce negative externalities, that the collection of taxes...