The Hain Celestial Group v. Sarah Palmquist, Individually and as Next Friend of E.P., a Minor

The Court unanimously said a final federal judgment must be set aside when the case lacked complete diversity (all plaintiffs must be from different states than all defendants) when it was moved from state court. An earlier mistaken dismissal of a nondiverse party cannot fix that problem.

Justice Sotomayor wrote the 9–0 opinion, joined by Chief Justice Roberts and Justices Alito, Kagan, Gorsuch, Kavanaugh, Barrett, and Jackson; Justice Thomas concurred.

Justice Sotomayor wrote for a unanimous 9-0 Court.

Majority

Sotomayor

Roberts

Thomas

Alito

Kagan

Gorsuch

Kavanaugh

Barrett

Jackson

““Rule 21 does not permit overriding a plaintiff's choice of state forum in product liability cases.””

Product-liability plaintiffs who sue a defendant from their own state cannot lose their chosen state forum because a federal court wrongly dismissed that defendant. Companies cannot rely on a later final judgment to cure an improper move to federal court.

Lower courts must apply the decision when reviewing cases moved from state to federal court without complete diversity. Parties with affected final judgments can seek to have those judgments set aside under this rule.

The Court said an improper move from state to federal court cannot be cured by later dismissing a nondiverse defendant. The final federal judgment must be set aside.

Plaintiffs in product-liability cases are protected when they choose state court and properly sue a defendant from their own state. Corporate defendants cannot use a later dismissal to preserve federal court jurisdiction.

Lower courts must follow the Court's rule in similar cases. Parties may ask courts to set aside final federal judgments entered after an improper removal.