One of the trickiest types of dangerous activity on Facebook to track is Coordinated Inauthentic Behavior. This is when many entities, users, pages, groups, advertisers act, fraudulently, to advance a specific aim. The most infamous case of this is when the Russian organization Internet Research Agency creating tens of thousands of inauthentic entities across Facebook's family of apps and producing propoganda that was viewed by over 150 million Americans in advance of the 2016 US Presidential Election.