Definition from Nolo’s Plain-English Law Dictionary
A federal case management procedure in which a federal panel transfers several (or many) complex civil cases involving one or more common questions of fact to one federal district court (called the MDL court). The MDL court coordinates and oversees pretrial proceedings, signs off on settlement of some cases, and dismisses others. All remaining cases are sent back to the original court of filing for trial. MDL works well when plaintiffs nationwide file lawsuits against the same defendants, alleging the same issues. Types of litigation that lend themselves to MDL include cases against pharmaceutical drug companies, lawsuits based on an airplane crash, securities fraud cases, and some employment cases.