They can do what ever they want. They can communicate with their pals privately.
However, they should have respect for other people on board as well. Knocking down the stock for their gains to create panic or doubt in other people mind is low and not professional at all. This has been going on with some people for a while.
He has done several time the same thing. Every time the stock try to make a new high of the day or 52 weeks high. He comes with his opinion, because he is short or want to buy cheaper.
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