DC Local Rule 405(a)(3)

(a) Definition

(3) Civil cases are deemed related when the earliest is still pending on the merits in the District Court and they (i) relate to common property, or (ii) involve common issues of face, or (iii) grow out of the same event or transaction or (iv) involve the validity or infringement of the same patent. Notwithstanding the foregoing, a case filed by a pro se litigant with a prior case pending shall be deemed related and assigned to the judge having the earliest case. However, if a judge in the interest of judicial economy, consolidates a significant number of similar pro se prisoner complaints, or has a single case with a significant number of pro se prisoner plaintiffs, and any of those prisoners later files a new complaint which is unrelated to the subject matter of the consolidated cases or the multiple plaintiffs' case, the judge who receives the new case as related may, if he or she chooses, refer the new case to the Calendar Committee for random assignment.

(b) Notification of Related Cases

(3) Whenever an attorney for a party in a civil or criminal action becomes aware of the existence of a related case or cases, the attorney shall immediately notify, in writing, the judges on whose calendars the cases appear and shall serve such notice on counsel for all other parties. Upon receiving information from any source concerning a relationship between pending cases, the Clerk shall transmit that information in writing to the judges on whose calendars the cases appear and to all parties to the proceeding.