Subject Matter Jurisdiction

Subject matter jurisdiction is a court's authority to hear a particular type of case. Unlike personal jurisdiction, subject matter jurisdiction cannot be waived by the parties, a court without subject matter jurisdiction lacks power to act, and any judgment it enters is void.

Federal court subject matter jurisdiction

Federal question jurisdiction (28 U.S.C. § 1331): the case arises under federal law. The "well-pleaded complaint" rule requires the federal question to appear on the face of the plaintiff's complaint, not as an anticipated defense.

Diversity jurisdiction (28 U.S.C. § 1332): complete diversity of citizenship between plaintiffs and defendants, plus an amount in controversy exceeding $75,000, exclusive of interest and costs.

Supplemental jurisdiction (28 U.S.C. § 1367): federal courts may hear claims so related to claims within their original jurisdiction that they form part of the same case or controversy, subject to the limits in § 1367(b) and (c).

Texas state court subject matter jurisdiction

District courts have general jurisdiction over civil matters with no monetary cap, subject to specialized courts (probate, family). County courts have limited jurisdiction with statutory caps. Justice courts handle small claims (currently $20,000 or less). The Texas Business Court has concurrent jurisdiction with district courts over specified business disputes, generally where the amount in controversy exceeds $5 million (the threshold under both Tex. Gov't Code § 25A.004(b) and (d) since HB 40 took effect September 1, 2025). Actions of the kinds listed in § 25A.004(b) have no threshold when a publicly traded company is a party (§ 25A.004(c)).

Challenges to subject matter jurisdiction

Subject matter jurisdiction may be challenged at any stage of litigation, including for the first time on appeal or by the court sua sponte. Parties cannot stipulate to subject matter jurisdiction that does not exist.