Of course, happens all the time. Google pump and dump - see the crazy stories about how organises some of these schemes are.
I think If the company has high liquidity, it is used by big banks and companies. For profit speculation. They have an informal arrangement among themselves to buy the currency of EN masse. Thus creating hype and artificial demand for currencies that currently no supply.
Financial collusion poses the greatest danger to all types of markets. Stock market players often use speculative methods to generate quick profits. Various methods of manipulation From information technology to everyday psychology is used.