Does a district court's erroneous dismissal of a nondiverse party before final judgment cure a jurisdictional defect that existed when a case was removed to federal court? Specifically, the Court addresses whether a judgment on the merits must be vacated if the dismissal of the nondiverse party is later found to be incorrect. The case further considers whether Federal Rule of Civil Procedure 21 can be used to dismiss a nondiverse party to preserve jurisdiction over an incorrectly removed case.

• The correctness of the District Court's dismissal of Whole Foods is irrelevant because the parties were completely diverse by the time final judgment was entered.
• Vacating the judgment would be wasteful and inefficient, as it would require the parties to litigate a new trial in state court.
• Even if the jurisdictional defect remained, Whole Foods should be dismissed now under Federal Rule of Civil Procedure 21 to preserve federal jurisdiction.

• The District Court lacked diversity jurisdiction at the time of removal because Whole Foods and the Palmquists were all citizens of Texas, violating the requirement of complete diversity under 28 U. S. C. § 1332(a).
• The erroneous dismissal of Whole Foods did not cure the jurisdictional defect, meaning the defect "lingered through judgment" and requires vacatur.
• As the "master of the complaint," the respondents have the right to choose their forum and should not be forced into federal court via Rule 21.

• The Court held that the District Court's erroneous dismissal of Whole Foods did not cure the jurisdictional defect, and thus the judgment in Hain's favor must be vacated.
• Federal courts are courts of limited jurisdiction, and appellate courts generally assess jurisdiction based on "the state of facts that existed at the time of fling" per *Grupo Datafux v. Atlas Global Group, L. P.*.
• While *Caterpillar Inc. v. Lewis* allows a judgment to stand if a jurisdictional defect is "cured" before final judgment, this requires a proper dismissal, not an erroneous one.
• The dismissal of Whole Foods was "interlocutory," meaning it "did not dispose of the whole case" and "merge[d] into the fnal judgment" for review per *Dupree v. Younger*.
• Because the Fifth Circuit reversed the dismissal, Whole Foods was restored to the case, proving the jurisdictional defect "lingered through judgment" and requiring vacatur under *Caterpillar*.
• The Court rejected the idea that a court can create jurisdiction through its own mistakes, noting in *Kokkonen v. Guardian Life Ins. Co. of America* that federal power "is not to be expanded by judicial decree."
• Efficiency considerations from *Caterpillar* only apply to excuse noncompliance with removal statutes *after* a defect has been properly and finally cured, not to excuse a lack of jurisdiction itself.
• The Court declined to use Federal Rule of Civil Procedure 21 to dismiss Whole Foods, noting that while *Newman-Green, Inc. v. Alfonzo-Larrain* allows dismissing dispensable nondiverse parties, the plaintiff is generally "the master of the complaint" per *Royal Canin U. S. A., Inc. v. Wullschleger*.
• Forcing the respondents to litigate in federal court against their wishes would override their right to select the most advantageous forum, a right recognized in *Atlantic Marine Constr. Co. v. United States Dist. Court for Western Dist. of Tex.*.