While market manipulation is a no no it does appear to happen on a regular basis. The chances of it happening are always there. An example can be made from some of the stocks on my watch list, most of which I hold.
CAG. Down 5% today on a trade worth $4.
ACE. Buy 14c Sell 14.5c Last sale 15c . A mini buy here could drop the price
ADI. A smallish trade caused a 7% rise today
CFE. Lord only knows what is going on there
CNP. A hint of bad news from a taxi driver could have major effects.
FNT. A press release even suggesting a ministerial review or it's PNG licence would again have major effects.
MHL. Another mini trade could cause a 9% swing up or down by the quotes.
and so on and on down the list.
All it needs is a broker able to make cheap trades to play around a little and keep skimming a little here and a little there.
Is it happening all the time.