It's MM's signals sometimes you will see low sells and buys like 100-500 1,500 or high buys from the MM's these guys work in conjunction with each other. NITE is the big dog. Sometimes they buy when volume looks low to generate interest in the stock when the stock loses volume other times it is to accumalate shares or sell shares. You will see odd orders that don't match bid or ask if the stock is being shorted or pre-trades or T trades before and and after market. It makes your head dizzy...LOL