Either someone is getting out or Shorts...still betting that this will go down after legalization. Personally, I think its a larger holder that has held for a year or more and wants to lock in some gains. Hitting the bids with large blocks of 20-40K every half hour.
I think the Bulls have said, ok, if you want to sell, go ahead and sell. We will wait until you are done, then move it back up.
I see some flash trading happening now, so looks like it is shorts. And all MJ stocks now being hit.