Paul Ferrer—Senior Attorney
The United States Supreme Court decided a crucial question concerning a federal court’s removal jurisdiction in Royal Canin U.S.A., Inc. v. Wullschleger, 604 U.S. 22 (2025). If a complaint filed in a state court asserts a claim or claims under federal law, then the defendant may remove the case to the U.S. district court for the district and division embracing the place where the state action was filed. See 28 U.S.C. § 1441(a). And if the complaint also asserts a claim or claims under state law arising out of the same facts, then the federal court can exercise “supplemental jurisdiction” over those claims and adjudicate them too. See 28 U.S.C. § 1367(a). But what happens, as the Supreme Court put the question in Royal Canin, “if, after removal, the plaintiff amends her complaint to delete all the federal-law claims, leaving nothing but state-law claims behind? May the federal court still adjudicate the now purely state-law suit?” 604 U.S. at 25.
That question had divided the U.S. circuit courts of appeals, creating a split between those courts that had held that a post-removal amendment could not divest a federal court of jurisdiction and those courts that had reached the opposite conclusion. See id. at 29-30 & n.3. In Royal Canin, the Supreme Court, in an opinion delivered by Justice Kagan for a unanimous Court, sided with the latter camp, holding that “[w]hen an amendment excises the federal-law claims that enabled removal, the federal court loses its supplemental jurisdiction over the related state-law claims. The case must therefore return to state court.” Id. at 25-26; see also id. at 30 (“If … the plaintiff eliminates the federal-law claims that enabled removal, leaving only state-law claims behind, the court’s power to decide the dispute dissolves. With the loss of federal-question jurisdiction, the court loses as well its supplemental jurisdiction over the state claims.”).
The Court’s holding in Royal Canin brings the rule for removed cases into line with the rule for cases originally filed in federal court. That rule was established in Rockwell Int’l Corp. v. United States, 549 U.S. 457, 473-74 (2007): “[W]hen a plaintiff files a complaint in federal court and then voluntarily amends the complaint, courts look to the amended complaint to determine jurisdiction.” As Justice Kagan explained in Royal Canin, the Rockwell rule means that “when the plaintiff in an original case amends her complaint to withdraw the federal claims, leaving only state claims behind, she divests the federal court of adjudicatory power.” 604 U.S. at 32-33. So now the rule is the same whether the case is originally filed in federal court or first filed in state court and then removed to federal court: “an amendment excising all federal claims divests a court of supplemental jurisdiction over the remaining state claims” both “in an original case” and “also in a removed case.” Id. at 33.
The Court’s ruling in Royal Canin provides increased flexibility to plaintiffs who may want to include federal-law claims with their state-law claims but wish to avoid federal court at all costs. Now, such plaintiffs can initially include the federal-law claims and, then, if the action is removed to federal court, amend their complaint to delete the federal-law claims and force a remand to state court.
