many bitcoin price manipulation was a pretty big play.
therefore making huge profits but there are still problems as members of this makes bitcoin bitcoin prices do not ever fall from the previous lowest price.
There was a time when a simple news could impact the price of bitcoin but i think things are changing and if not for the forking and power struggle we would not see a price slide and even now the price is recovering,price manipulation is possible in alt coins where they have low volumes.If you are holding millions of dollars of millions worth of bitcoin then you could manipulate the price .