The Cable News Network (CNN), a 24-hour cable news channel, was founded by Ted Turner and first broadcast on June 1, 1980. The unflattering CNN nickname of “Certainly Not News” has been cited in print since at least 1993.
   
CNN has also been nicknamed the “Chicken Noodle News” (cited in print since 1981), the “Communist News Network” (cited in print since 1991), the “Clinton News Network” (cited in print since 1992), the “Cabal News Network” (cited in print since 1996), the “CIA News Network” (cited in print since 1997), the “Clown News Network” (cited in print since 1998), the “Criminal News Network” (cited in print since 1998), the “Corporate News Network” (cited in print since 1999), the “Counterfeit News Network” (cited in print since 1999), the “Cartoon News Network” (cited in print since 2000), the “Crescent News Network” (cited in print since 2002), “Crap Not News” (cited in print since 2007), “Criminally Negligent News” (cited in print since 2009), the “Collapsing News Network” (cited in print since 2010), the “American Pravda” (cited in print since 2012), the “Cuomo News Network” (cited in print since 2013), the “Collusion News Network” (cited in print since 2017) and the “Cuomo Nepotism Network” (cited in print since 2017).
       
 
Wikipedia: CNN
The Cable News Network (CNN) is an American basic cable and satellite television channel that is owned by the Turner Broadcasting System division of Time Warner. The 24-hour cable news channel was founded in 1980 by American media proprietor Ted Turner. Upon its launch, CNN was the first television channel to provide 24-hour news coverage, and was the first all-news television channel in the United States.
     
Google Groups: soc.culture.australian
CNN in Australia?
Julian Elischer
1/27/93
(...)
I assume this is the “CNN international” service I was amazed to see while in europe. From the week of it I saw there I understand now why people say that CNN stands for Certainly Not News!
   
Google Groups: rec.aviation.military
AGM-130???
David Lentz
1/27/99
(...)
John, I sure you have a much faith in CNN news as I do.  That and seventy-five cents will get you a cup of coffee.  Heard a new name for CNN today (Certainly Not News).  Taint bad.
   
Google Groups: alt.society.conservatism
! CNN Dorks It, Gets Caught Lying About Fox News
pithy
3/3/02
(...)
CNN stands for Certainly Not News.
 
Democratic Underground
CNN nicknames…
LibertyorDeath
Thu Oct-21-04 12:53 PM
1. CNN = Certainly Not News
 
Google Books
Battle for Our Minds:
Western Elites and the Terror Threat
By Michael Widlanski
New York, NY: Threshold Editions
2012
Pg. 319:
CHAPTER THREE: CNN: CERTAINLY NOT NEWS
 
Twitter
Marybeth L.
‏@marybethstime
CNN stands for : Certainly Not News!!!!!
9:33 PM - 23 Oct 2014