Grip it , It's pretty simple, when I first bought $Amrn and $NWBO EOY 2016, my broker at the time said, "These two are cult stocks which are often heavily shorted." So in other words, WS doesn't have an appetite for stocks it sees as languishing for years on end. The long time horizon helps them exploit fear based pump and dump schemes, which I saw with both stocks, with AF leading the way.
ILT