Jurisdiction

The MBE almost always tests jurisdiction through the waiver hierarchy: a defendant answers, litigates, then late-raises a defect. Personal jurisdiction is waived if omitted from the first Rule 12 motion or the answer (Rule 12(h)(1)), but subject-matter jurisdiction is never waived — the court must dismiss sua sponte whenever it finds a defect, even after judgment (Rule 12(h)(3)). The other recurring split is the two SMJ types: federal-question turns on the well-pleaded complaint rule (an anticipated federal defense, or even a federal counterclaim, does not count), while diversity demands complete diversity plus an amount exceeding $75,000.

Don’t confuse jurisdiction (the court’s power) with venue (the proper place) or standing (the plaintiff’s injury-based right to sue under Article III) — venue, like personal jurisdiction, is waivable, but standing is jurisdictional and not waivable. A classic trap: a corporation is a citizen of both its state of incorporation and its principal place of business (the “nerve center” under Hertz), so a defendant defeats diversity by sharing either with the plaintiff.