In the case of Mutual Pharmaceutical Company, Inc. v. Karen L. Bartlett (2012), the U.S Supreme Court ruled in favor of Mutual Pharmaceutical Co., overturning a $21 million verdict against them. The plaintiff, Karen Bartlett, had taken an anti-inflammatory drug called sulindac manufactured by Mutual and suffered severe side effects including burns on two-thirds of her body and near blindness as a result of toxic epidermal necrolysis. She sued for damages arguing that the company failed to warn about potential risks associated with their product and won at trial court level; however, this was overturned by the Supreme Court which held that federal law preempts state-law design-defect claims targeting generic drugs because under federal regulations generic drugs must be chemically equivalent to FDA-approved brand-name drugs thus leaving no room for manufacturers to alter composition or labeling without violating federal law.

In the dissenting opinion for Mutual Pharmaceutical Company, Inc. v. Karen L. Bartlett (2012), Justice Sonia Sotomayor, joined by Justice Ginsburg, argued that federal law does not preclude state-law design-defect claims against generic drug manufacturers. They contended that Congress intended to preserve a role for state tort law in supplementing FDA regulation of drugs and did not intend to make impossibility preemption as broad or as easy to establish as the majority suggests. The dissenters believed that the Court's decision leaves consumers of generic drugs without legal recourse when they are injured by unsafe drugs and undermines incentives for generic manufacturers to monitor safety after their products have been approved by FDA.