The seller hired a proffesional to sell the stock probably a Market Maker. Right now its running 2 to 1 sells Vs buys. And hasnt tanked.T trades are either AH trades or settlement trades.So lets say I sell shares for you all day and the total of all trades I make are settled after hours.To make it simple I sell 200,000 shares for you and after hours you settle up with me by giving me 200,000 shares. Usually done at a discount.