29 U.S.C. § 185 : US Code - Section 185: Suits by and against labor organizations

    (a) Venue, amount, and citizenship
      Suits for violation of contracts between an employer and a labor
    organization representing employees in an industry affecting
    commerce as defined in this chapter, or between any such labor
    organizations, may be brought in any district court of the United
    States having jurisdiction of the parties, without respect to the
    amount in controversy or without regard to the citizenship of the
    (b) Responsibility for acts of agent; entity for purposes of suit;
      enforcement of money judgments
      Any labor organization which represents employees in an industry
    affecting commerce as defined in this chapter and any employer
    whose activities affect commerce as defined in this chapter shall
    be bound by the acts of its agents. Any such labor organization may
    sue or be sued as an entity and in behalf of the employees whom it
    represents in the courts of the United States. Any money judgment
    against a labor organization in a district court of the United
    States shall be enforceable only against the organization as an
    entity and against its assets, and shall not be enforceable against
    any individual member or his assets.
    (c) Jurisdiction
      For the purposes of actions and proceedings by or against labor
    organizations in the district courts of the United States, district
    courts shall be deemed to have jurisdiction of a labor organization
    (1) in the district in which such organization maintains its
    principal office, or (2) in any district in which its duly
    authorized officers or agents are engaged in representing or acting
    for employee members.
    (d) Service of process
      The service of summons, subpena, or other legal process of any
    court of the United States upon an officer or agent of a labor
    organization, in his capacity as such, shall constitute service
    upon the labor organization.
    (e) Determination of question of agency
      For the purposes of this section, in determining whether any
    person is acting as an "agent" of another person so as to make such
    other person responsible for his acts, the question of whether the
    specific acts performed were actually authorized or subsequently
    ratified shall not be controlling.