╳ ɪ ᴡᴀɴɴᴀ ʙᴇ ᴀ sᴛᴀʀ

As far as the public is aware of, there are no genuine snuff films that have been catalogued by the FBI, or other law enforcement. 

By definition, a true snuff film is one that commits an act of murder to film expressly for the purpose of distributing it for profit.  This means that every step of the process was done with the intent of selling the footage (ergo, the filmed acts of serial killers, accidental deaths caught on film, or secretly filmed public executions do not count as snuff).  While there are many films that have been mistaken for snuff films (or even used the idea as a promotional gimmick), no real snuff film has ever surfaced.

Now, this does not mean that no such films exist at all, as we just don’t know what goes on in the underground.  The proven existence of forums such as the infamous (though now deleted) “Cannibal Cafe” do raise concerns of what might be trading hands for cash under humanity’s collective noses (the site is still archived on the internet, and even if it’s mostly just fantasy, the content is still highly disturbing).  That site in particular was responsible for a case of murder and cannibalism in Germany in 2001/2002.