Where is home depot "at home": Daimler v. bauman and the end of doing business jurisdiction

In January 2014, the U.S. Supreme Court decided Daimler AG v. Bauman. The case was supposed to resolve a very important question that had divided courts for decades: when, for jurisdictional purposes, can the contacts of a subsidiary be imputed to its parent? The Supreme Court dodged this question. Instead, it answered a different, but equally important, question: under what circumstances is a corporation "at home" such that a state has general jurisdiction over it? The Court had introduced the "at home" language to the discourse on general jurisdiction a few years earlier in Goodyear Dunlop Tires Operations, S.A. v. Brown, when it held that a state has general jurisdiction over a corporation if its activities within the state are so continuous and systematic as to render the corporation essentially "at home" there. At the time, courts and commentators were not one-hundred percent clear on the meaning of the "at home" language. After Daimler, they will be.