mb: SETS trading means that every buy is matched by a sell and vice versa. The closing auction price is the top price paid as the buy sell sides are matched. In this case the bid was put in over offer and arithmetically there were more than enough at the final offer to settle the bid. In other words it is encouraging that there is buying at more than the pre auction close bid: forget whether it's a buy or a sell: or in other words we had a strong finish and makes the retrace scenario less likely from the double top on the chart.