Bitcoins price is based on supply and demand on the market.More demand higher price more supply down price.Yes you can manipulate bitcoins price if you hold a huge supply or supply that may be enough to sell or buy in the current market status
I do not think that there are many people who hold a large number of bitcoins in order to manipulate the price. But this assumption can not be ignored.
The bitcoin price can't be manipulated, The chinese community not having an enough power to manipulate the bitcoin again. and i think the people with a lot of the bitcoin in their hand just give an impact to make the market will be panic and more newbies try to dump his coin. It will not make the bitcoin easy to get a manipulate by every parties.
Unlike other currencies bitcoin is not centralized and it is not controlled by anyone, the only ones who can change its situation is us the community and if we want to change the price all we have to do is either hold and the price will go up or dump it and the price will go down as simple as that.