just a random sample, in no particular order . . . newsdemon, giganews, easynews, and eternal-september appear to be among the worst offenders,
but every news server in the world belongs somewhere further down this
very long list of peers that enable and tolerate the usenet troll farm, particularly those that allow mass crossposting and unlimited postings:

HeartDoc Andrew - newsdemon.com
Peeler - newsdemon.com
Quack Andrew B. Chung - newsdemon.com
NefeshBarYochai - usenet.farm
Michael Christ - eternal-september.org
Governor Swill - easynews.com
Siri Cruise - eternal-september.org
FPP - eternal-september.org
Mitchell Holman - uzoreto.com / vipernews.com
FBInCIAnNSATerroristSlayer - eternal-september.org
% - giganews.com
Klaus Schadenfreude - giganews.com
Cardinal de Here - eternal-september.org
Richard Hachel - nemoweb.net
Rudy Canoza - easynews.com
AlleyCat - eternal-september.org
Alan - eternal-september.org
Rich - solani.org
Andrew - solani.org
BTR1701 - giganews.com
shawn - eternal-september.org
trotsky - astraweb.com
Adam H. Kerman - eternal-september.org
David Dalton - eternal-september.org
Ian J. Ball - eternal-september.org
anim8rfsk - easynews.com
pothead - eternal-september.org
DocUFO - eternal-september.org
Steven Douglas - tweaknews.nl
JTEM - eternal-september.org
rjac - theworld.com
R Kym Horsell - blueworldhosting.com
Loran - eternal-september.org
useapen - eternal-september.org
Intelligent Party - eternal-september.org
ad infinitum...

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