basically when the stock reaches an ask of .0001 then it is at no bid. in other words there are more sellers trying to sell at 0001 than buyers to buy them. So as a result there are no pending transactions as there are no buyers left. I have however seen transactions occur below the price of .0001 on a no bid stock. so it is possible, but doensn't happen very often because most brokers only allow four decimal places....IMO