United States Code/Title 28/Chapter 85/Section 1332
(a) The district courts shall have original jurisdiction of all civil actions where the matter in controversy exceeds the sum or value of $75,000, exclusive of interest and costs, and is between—
(1) citizens of different States;
(2) citizens of a State and citizens or subjects of a foreign state;
(3) citizens of different States and in which citizens or subjects of a foreign state are additional parties; and
(4) a foreign state, defined in section 1603 (a) of this title, as plaintiff and citizens of a State or of different States.
For the purposes of this section, section 1335, and section 1441, an alien admitted to the United States for permanent residence shall be deemed a citizen of the State in which such alien is domiciled.

(b) Except when express provision therefor is otherwise made in a statute of the United States, where the plaintiff who files the case originally in the Federal courts is finally adjudged to be entitled to recover less than the sum or value of $75,000, computed without regard to any setoff or counterclaim to which the defendant may be adjudged to be entitled, and exclusive of interest and costs, the district court may deny costs to the plaintiff and, in addition, may impose costs on the plaintiff.

(c) For the purposes of this section and section 1441 of this title—
(1) a corporation shall be deemed to be a citizen of any State by which it has been incorporated and of the State where it has its principal place of business, except that in any direct action against the insurer of a policy or contract of liability insurance, whether incorporated or unincorporated, to which action the insured is not joined as a party-defendant, such insurer shall be deemed a citizen of the State of which the insured is a citizen, as well as of any State by which the insurer has been incorporated and of the State where it has its principal place of business; and
(2) the legal representative of the estate of a decedent shall be deemed to be a citizen only of the same State as the decedent, and the legal representative of an infant or incompetent shall be deemed to be a citizen only of the same State as the infant or incompetent.

(d)
(1) In this subsection—
(A) the term “class” means all of the class members in a class action;
(B) the term “class action” means any civil action filed under rule 23 of the Federal Rules of Civil Procedure or similar State statute or rule of judicial procedure authorizing an action to be brought by 1 or more representative persons as a class action;
(C) the term “class certification order” means an order issued by a court approving the treatment of some or all aspects of a civil action as a class action; and
(D) the term “class members” means the persons (named or unnamed) who fall within the definition of the proposed or certified class in a class action.
(2) The district courts shall have original jurisdiction of any civil action in which the matter in controversy exceeds the sum or value of $5,000,000, exclusive of interest and costs, and is a class action in which—
(A) any member of a class of plaintiffs is a citizen of a State different from any defendant;
(B) any member of a class of plaintiffs is a foreign state or a citizen or subject of a foreign state and any defendant is a citizen of a State; or
(C) any member of a class of plaintiffs is a citizen of a State and any defendant is a foreign state or a citizen or subject of a foreign state.
(3) A district court may, in the interests of justice and looking at the totality of the circumstances, decline to exercise jurisdiction under paragraph (2) over a class action in which greater than one-third but less than two-thirds of the members of all proposed plaintiff classes in the aggregate and the primary defendants are citizens of the State in which the action was originally filed based on consideration of—
(A) whether the claims asserted involve matters of national or interstate interest;
(B) whether the claims asserted will be governed by laws of the State in which the action was originally filed or by the laws of other States;
(C) whether the class action has been pleaded in a manner that seeks to avoid Federal jurisdiction;
(D) whether the action was brought in a forum with a distinct nexus with the class members, the alleged harm, or the defendants;
(E) whether the number of citizens of the State in which the action was originally filed in all proposed plaintiff classes in the aggregate is substantially larger than the number of citizens from any other State, and the citizenship of the other members of the proposed class is dispersed among a substantial number of States; and
(F) whether, during the 3-year period preceding the filing of that class action, 1 or more other class actions asserting the same or similar claims on behalf of the same or other persons have been filed.
(4) A district court shall decline to exercise jurisdiction under paragraph (2)—
(A)
(i) over a class action in which—
(I) greater than two-thirds of the members of all proposed plaintiff classes in the aggregate are citizens of the State in which the action was originally filed;
(II) at least 1 defendant is a defendant—
(aa) from whom significant relief is sought by members of the plaintiff class;
(bb) whose alleged conduct forms a significant basis for the claims asserted by the proposed plaintiff class; :::::and
(cc) who is a citizen of the State in which the action was originally filed; and
(III) principal injuries resulting from the alleged conduct or any related conduct of each defendant were incurred in the State in which the action was originally filed; and
(ii) during the 3-year period preceding the filing of that class action, no other class action has been filed asserting the same or similar factual allegations against any of the defendants on behalf of the same or other persons; or
(B) two-thirds or more of the members of all proposed plaintiff classes in the aggregate, and the primary defendants, are citizens of the State in which the action was originally filed.
(5) Paragraphs (2) through (4) shall not apply to any class action in which—
(A) the primary defendants are States, State officials, or other governmental entities against whom the district court may be foreclosed from ordering relief; or
(B) the number of members of all proposed plaintiff classes in the aggregate is less than 100.
(6) In any class action, the claims of the individual class members shall be aggregated to determine whether the matter in controversy exceeds the sum or value of $5,000,000, exclusive of interest and costs.
(7) Citizenship of the members of the proposed plaintiff classes shall be determined for purposes of paragraphs (2) through (6) as of the date of filing of the complaint or amended complaint, or, if the case stated by the initial pleading is not subject to Federal jurisdiction, as of the date of service by plaintiffs of an amended pleading, motion, or other paper, indicating the existence of Federal jurisdiction.
(8) This subsection shall apply to any class action before or after the entry of a class certification order by the court with respect to that action.
(9) Paragraph (2) shall not apply to any class action that solely involves a claim—
(A) concerning a covered security as defined under 16(f)(3) of the Securities Act of 1933 (15 U.S.C. 78p (f)(3) ) and section 28(f)(5)(E) of the Securities Exchange Act of 1934 (15 U.S.C. 78bb (f)(5)(E));
(B) that relates to the internal affairs or governance of a corporation or other form of business enterprise and that arises under or by virtue of the laws of the State in which such corporation or business enterprise is incorporated or organized; or
(C) that relates to the rights, duties (including fiduciary duties), and obligations relating to or created by or pursuant to any security (as defined under section 2(a)(1) of the Securities Act of 1933 (15 U.S.C. 77b (a)(1)) and the regulations issued thereunder).
(10) For purposes of this subsection and section 1453, an unincorporated association shall be deemed to be a citizen of the State where it has its principal place of business and the State under whose laws it is organized.
(11)
(A) For purposes of this subsection and section 1453, a mass action shall be deemed to be a class action removable under paragraphs (2) through (10) if it otherwise meets the provisions of those paragraphs.
(B)
(i) As used in subparagraph (A), the term “mass action” means any civil action (except a civil action within the scope of section 1711 (2)) in which monetary relief claims of 100 or more persons are proposed to be tried jointly on the ground that the plaintiffs’ claims involve common questions of law or fact, except that jurisdiction shall exist only over those plaintiffs whose claims in a mass action satisfy the jurisdictional amount requirements under subsection (a).
(ii) As used in subparagraph (A), the term “mass action” shall not include any civil action in which—
(I) all of the claims in the action arise from an event or occurrence in the State in which the action was filed, and that allegedly resulted in injuries in that State or in States contiguous to that State;
(II) the claims are joined upon motion of a defendant;
(III) all of the claims in the action are asserted on behalf of the general public (and not on behalf of individual claimants or members of a purported class) pursuant to a State statute specifically authorizing such action; or
(IV) the claims have been consolidated or coordinated solely for pretrial proceedings.
(C)
(i) Any action(s) removed to Federal court pursuant to this subsection shall not thereafter be transferred to any other court pursuant to section 1407, or the rules promulgated thereunder, unless a majority of the plaintiffs in the action request transfer pursuant to section 1407.
(ii) This subparagraph will not apply—
(I) to cases certified pursuant to rule 23 of the Federal Rules of Civil Procedure; or
(II) if plaintiffs propose that the action proceed as a class action pursuant to rule 23 of the Federal Rules of Civil Procedure.
(D) The limitations periods on any claims asserted in a mass action that is removed to Federal court pursuant to this subsection shall be deemed tolled during the period that the action is pending in Federal court.

(e) The word “States”, as used in this section, includes the Territories, the District of Columbia, and the Commonwealth of Puerto Rico. 

Section 1332