What is the closing auction trading period (CAS)?

The closing bidding trading period (CAS) is divided into four stages from 16:00 to 16:10: the reference price pricing period (1 minute), the input trading time (5 minutes), the irrevocable period (2 minutes), and the random closing time (2 minutes).

[Reference price pricing (16:00 to 16:01)]
Reference price:calculation and publication
Order modification:cannot enter, cancel and change

[Enter order period (16:01 to 16:06)]
Price limit: ±5% of the reference price
Order type: At-auction order, At-auction limit order
Order modification: input, cancel and change

[Irrevocable period (16:06 to 16:08)]
Price limit: between the lowest selling price and the maximum
Order type: At-auction order, At-auction limit order
Order modification: input, cancel and change

[Random closing time (16:08 to 16:10)]
Price limit: between the lowest selling price and the maximum
Order type: At-auction order, At-auction limit order
Order modification: input, cancel and change
Note: The actual closing time is randomly determined by the system

[Phase I]
1. Major index components: the Hang Seng Composite large Stock Index and the Hang Seng medium-sized Stock Index, with H shares corresponding to A shares;
2. All exchange-traded funds.

[Phase II] (currently applicable)
1. The list of securities was expanded to include stocks in the Hang Seng Composite Index;
2. The second stage includes the scope of application of the first stage.