When M&M's get caught unaware- when big news hits or shorts are covering on a stock such as TIVO, which has a large short position, the M&M's are then flooded with buy orders. M&M's make the most money when buys and sells are equal and many. So they get a piece of each one and do not go short. M&M's are short term traders. They buy cheap, sell for a modest gain, short, drive the price down, cover and go long again. When M&M's see a flurry of orders for buys, as then the shorts are covering, they fill some and raise the ASK. At somepoint, maybe in the next trading session they will drop the ASK and BID and try to fill as few orders on the BID as possible, until they can cover themselves. This is what is called, walking it down. For many of you, the shorts will harm you when they cover, because you will chase to buy. Again, if you want to own this stock, buy on normal volume.