Collecting insignia from the Federal Bureau of Investigation since 1999.
This site is not officially sanctioned by the Department of Justice, The Federal Bureau of Investigation, The Louisville Metro Police Department, or any of their entities.
©  Copyright 1999-2006.  All Rights Reserved.
Made for the FBI Chicago’s Special Operations Group, this patch contains the term “Cave Dwellers” because the original office of the SOG was located in the basement of the FBI Field Office there and had no windows.  Many of the agents said they felt like they were “stuck in a cave”  Hence, they started to refer to themselves as “Cave Dwellers” and chose the Batman theme in reference to the Bat Cave. 

Source: Ryder Lusk and SSA Andrew Wilson