In a class action lawsuit, a lead plaintiff (also called class representative, named plaintiff, or representative plaintiff) is the named party, who files the case and represents the group. The court appoints this party when it certifies the lawsuit as a class action.
The lead plaintiff must be able to represent the interests of all the members of the class, by being typical of the class members and not having conflicts with them. He or she is responsible to hire the attorney, file the lawsuit, consult on the case, and agree to any settlement. In exchange, the lead plaintiff is entitled to compensation (at the discretion of the court) out of the recovery amount.
References
Lead plaintiff Wikipedia(Text) CC BY-SA