I suspect any Broker Dealer doing that is short/sold naked shares/carrying FTD's (failure to deliver) and concerned the next run up will cost them dearly. My brokers call me rarely to never but the few times they have over the years I've politely explained that I pay them to execute my orders as opposed to their free advice.
thats an easy one, they have a buyer who wants them cheap, and looking for a sucker to sell into pull back, which was created by them in the first place.
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