There are now five states involved in litigation over the question of whether sufficient nexus exists to support state sales tax on tangible personal property and service where the sales are made via the internet without the seller having any physical presence in the taxing state. Generally, the states are attempting to justify nexus based solely on economic activity rather than the traditional activities that were identified by the US Supreme Court in Quill v North Dakota. The states involved include Alabama, Indiana, South Dakota, Tennessee, and Wyoming.