They do it all the time
Killdogs group is so stupid they lost money with insider trading
https://www.armstrongeconomics.com/armstrongeconomics101/economics/buffet-sold-all-airlines-in-advance/
https://www.armstrongeconomics.com/international-news/north_america/2016-u-s-presidential-election/emails-expose-hillary-insider-trading-on-greek-bailouts/
https://www.armstrongeconomics.com/world-news/corruption/its-time-to-investigate-the-players-to-prove-the-public-have-been-manipulated-for-personal-gain/
Buffett Sold All Airlines in Advance? | Armstrong Economics
https://www.youtube.com/watch?v=VDE9ckVnu_M Buffet did not sell all airlines BEFORE the COVID Crisis for even he is too smart to do that, despite the fact that
https://www.armstrongeconomics.com/armstrongeconomics101/economics/buffet-sold-all-airlines-in-advance/
