The opening gap and the US overnight

Two gaps a day, not one

An NQ trader knows one gap: the one between the 10 pm US cash close and its 3:30 pm open the next day, which the Globex night has more or less filled. The DAX has two gaps, because it has two cash markets to reconcile: its own and the United States'.

• The 9 am gap: between the 5:30 pm Xetra close and the next day's Xetra open. It contains the American evening, the Asian night, and the 8 am numbers. The FDAX has already largely integrated it, since it traded all night; but the cash market opens with a jump, and the 9 am auction is the moment that jump is accepted or contested by the stocks themselves.
• The 3:30 pm gap: between the previous day's US cash close and its open. It contains the European morning. The ES integrated it in its overnight; but at the open, the American participants who did not take part in the overnight arrive, and that is where the DAX's morning is validated or reversed.