(1) driving the PK stock price upward, (2) obstructing others' purchase orders by placing orders at multiple price levels and (3) driving up the opening or the closing prices by placed orders

included (1) driving the PROS stock price upward , (2) obstructing others' purchase orders by placing orders at multiple price levels and (3) driving up the opening or the closing prices by placed

drive up prices, and submitting buy orders during the pre-opening or closing periods to manipulate opening or closing prices. The specific instances of manipulation occurred during the following periods