If you mean by controling the bitcoin its price, then it is supply and demand which control it.
Bitcoin is a decentralized currency so every one who run a node, every miner and every holder, are sharing the control in somehow
That's the beauty of bitcoins that it is not controlled by anyone, any authority. It is the people's currency on which only people have control. That's the best part of it. It can be anyone, holders or miners of bitcoins. Only the people who uses bitcoins are it's owner.
Yep, this is just as its name its suggest. Cryptocurrency. Mean to say it's just about the same as any other currency there is. Noone actually controls them. The general market depends its values.