Traditionally, the United States Supreme Court has followed a presumption against pre-emption. In June, however, in the case of Pliva v. Mensing, 131 S.Ct. 2567 (2011), the Court ruled in favor of federal pre-emption of failure-to-warn claims brought against generic manufacturers of prescription drugs under state law.

Mensing is seemingly inconsistent with the Court’s ruling two years ago in Wyeth v. Levine, 129 S.Ct 1187 (2009). In the Levine decision, often touted as the “mother” of all pre-emption rulings, the high Court found that failure-to-warn claims asserted against name-brand prescription drug manufacturers are not pre-empted by federal law. Accordingly, because Mensing represents such a significant development in the law of federal pre-emption, it is certain to have considerable impact on product liability law, generally, and prescription drug liability specifically.

The Historical Underpinnings ofImplied Pre-emption