Not an expert at all but the way WSB explains it, it’s where hedge funds trade GME back and forth between each other, gradually lowering the price with each trade. It’s a coordinated effort toy manipulate the market and is illegal. According to WSB the SEC either doesn’t care or fines hedge funds so little for stuff like this that it’s worth it to them to do it anyways (as well as selling naked short and under reporting short interest). As I said, I have been watching what WSB is doing for entertainment value so all of this is suspect.