@kirtap:
Pre CSPA
Between 4:00 pm and 4:10 pm, Sydney time, the market is placed in Pre-CSPA. Trading stops and brokers enter, change and cancel orders in preparation for the market closing.
Closing Single Price Auction
The Closing Single Price Auction takes place between 4:10* pm and 4:12 pm, Sydney time.
ASX Trade calculates closing prices during this phase.