Section 49 Parties to proceedings under this Act.

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Rules of court may make provisionF2... with respect to the joinder as parties to proceedings under this Act of persons involved in allegations of F3... improper conduct made in those proceedings, and with respect to the dismissal from such proceedings of any parties so joined; and rules of court made by virtue of this subsection may make different provision for different cases.

F4In every case in which the court considers, in the interest of any person not already a party to the suit, that that person should be made a party to the suit, the court may if it thinks fit allow that person to intervene upon such terms, if any, as the court thinks just.