What is a docket number?

According to the University of California Berkeley Law Library, a docket number is a reference number assigned to each filed legal action. The docket number allows the action to be tracked during and after the time that it is active in the court system.

The UC Berkeley Law Library explains that the docket number contains information relating to the year the action is filed followed by a sequential reference number. The docket number might also contain numbers representing the location where the action is filed and letters representing the court in which it is filed, as well as the initials of the judge and magistrate to which it is assigned.