Walmart and Target are not extending their online price war over book advance orders (see “Booksellers Go to Dept. of Justice”) to Wisconsin, where the stores will not ship books at below cost.  Amazon continues to accept orders from Wisconsin for the heavily discounted titles. 

Wisconsin has a unique law, the Unfair Sales Act, which prohibits sales of certain goods below cost.  Walmart and Target have stores in the state; Amazon does not.