RE: What is an UT trade8 May 2020 18:41
Uncrossing Trade....occurs just before and after the market opens at 8:00am and just after close at 4:30pm. There is a short time period where dealing of shares is undertaken. Orders placed to buy and orders to sell a share are matched off ( uncrossed) and the average price used to determine an opening price at 8am (or slightly just after 8am). The idea is to maximise the volume of shares traded so the big orders are dealt with first.
At 4:30pm, there is another round of matching sells to buys. The process lasts for 10 mins or so. This sets the start price for the next market day.
There are rules and regs that apply to stop " manipulation" of share prices.
Unless you pay for this facility then you cannot participate in these trading period. Traders who do have the facility can also buy/sell on an ad-hoc basis, raising new orders in the time window . For example, they might see a big sell order and think " I'll have some of that at that price!"