In February of last year, we reported on the Sixth Circuit’s split-panel holding that it had jurisdiction to review challenges to the validity of the “Clean Water Rule” (which clarifies the term “waters of the United States” in the Clean Water Act). Last week, the Supreme Court granted certiorari in National Association of Manufacturers v. Department of Defense. While interlocutory cert petitions are typically disfavored by the Supreme Court, jurisdictional issues have long been an exception to that rule of thumb. The Court’s ultimate analysis in this case could potentially inform the interpretation of other jurisdictional statutory provisions, beyond the Clean Water Act.