The Opening cross begins at 9:28 AM. At this time the NASDAQ Market Center Execution System automatically executes orders. Orders placed after 9:28 AM may not be cancelled. Orders placed after 9:28 AM may only be changed if the change to the order makes the order more aggressive. A change that increases the size of the order or improves the price would make the order more aggressive. For a buy order an improved price would be a higher limit price, for a sell order an improved price would be a lower limit price. All orders that are executed during the opening cross will be reported to ACT with a .T modifier. The official NASDAQ opening print is disseminated by the system at “9:30 X”.
Orders that are entered prior to the opening for regular hours execution may not be canceled or modified during the opening cross.