Today, a divided US Supreme Court issued its opinion in South Dakota v. Wayfair, Inc., 585 US ____ (2018), upholding a South Dakota law imposing sales tax collection obligations on retailers with an economic presence in the state. The opinion overturns the decades-old rule enunciated in Quill Corp. v. North Dakota and National Bellas Hess, Inc. v. Dep’t of Revenue of Ill. requiring an in-state physical presence before a state could impose tax collection obligations on a seller.

Describing the physical presence rule as “unsound and incorrect,” the majority pointed to “the far-reaching systematic and structural changes in the economy” brought on by the growth of e-commerce and the unfair market distortions created by the rule as reasons for overturning the precedent. In his dissent, Chief Justice Roberts criticized the majority for “breezily disregard[ing]” concerns about compliance burdens and said that any change should have been left up to Congress.

What remains unclear is how the opinion will impact existing state laws. While the majority viewed the limitation in South Dakota’s law favorably (sellers must first surpass certain sales thresholds and the law applies prospectively only), as many as 30 other states also have some version of an economic nexus law. The court merely noted that “[t]hese burdens may pose legitimate concerns in some instances,” leaving the door open for further litigation or the possibility of a uniform federal standard adopted by Congress.

Justice Kennedy delivered the opinion of the court, in which Justices Thomas, Ginsburg, Alito, and Gorsuch joined. Justices Thomas and Gorsuch also filed concurring opinions. Chief Justice Roberts filed a dissenting opinion, in which Justices Breyer, Sotomayor, and Kagan joined.