PLIVA, Inc. v. Mensing was an enormous and, by some predictions, unexpected victory for generic drug manufacturers (“the Generics”). The Supreme Court held that state law failure-to-warn claims against the Generics—the core claims in generic drug cases—were preempted. The Court found impossibility preemption because the Generics, unlike their brand-name counterparts, were prohibited by federal law from independently strengthening their drug labels.