It was noted during the out of hours 'drops' that a big player had set up a lot of support buy orders to prevent the price being driven down too far.

Retail investors did the job (by buying shares and not selling, creating fewer sell orders) but someone had their backs when the sneaky bastards tried to drive the price down through everyone's stop orders (automatic sell when price drops below a certain point) - what prevented this was a most people bought the stock without placing any stops so there was nothing to trigger :)