BTC while you sell they only buy

BITSTAMP:BTCUSD   Bitcoin / U.S. Dollar
Hello, I have been examining and seeing the same strategy for days, they stop the demand and activate the offer through bots, to keep the price in a certain value range in which they are accumulating, be careful with this game of selling to accumulate but, at some point, when you least expect it, you will come or go short and you will miss the train.
Trade active: initially I put a pennant I do not really know why I did it, but before going long I realized the error, at the moment the graph remains the same only without the pennant