The US Supreme Court held on May 20 that a judge, not a jury, must decide the question of whether federal law prohibited drug manufacturers from adding warnings to the drug label that would satisfy state law. To succeed on a pre-emption defense on failure-to-warn claims, the drug manufacturer must present “clear evidence” that it fully informed the US Food and Drug Administration (FDA) of the justifications for the warning, and that the FDA, in turn, informed the drug manufacturer that the FDA would not approve the addition of the warning to the drug’s label. The Court remanded to the US Court of Appeals for the Third Circuit to decide the pre-emption question. Two concurring opinions provide the Third Circuit with roadmaps to opposite conclusions.