One theory - Stock manipulators on both sides of trade. A couple guys could be in collusion who submits low bits and themselves buy – driving price down artificially causing panic individuals to sell their shares – they in turn quickly scoop up and then allow price to rise – once back to normal level they sell and take the profits – then start the game all over again. Very difficult to do this when demand is high and stock not a penny stock. Saw this on the news – a couple guys were arrested doing this.