ASX Limited (“ASX”) advises that a number of changes have been made to the ASX Operating Rule Procedures and that these changes are to become effective from 12 May 2025. The changes allow for the implementation of the following aspects of ASX Service Release 15 (ASX SR 15), due to go live on 12 May 2025 (first release):  

·       Streamlined trade reporting for late trades and block trades by reducing the number of reportable codes. We are taking this opportunity to simplify the trade reporting process as well as making this section of the rulebook more streamlined and less complex by removing repetitive and redundant detail. We are harmonising some trade report names with the ASIC Market Integrity Rules (Securities) where possible;

·       Removal of the Open Auction stagger;

·       Introduction of new Session States - Opening Single Price Auction (OSPA) and Post Close;

·       Fixed open time for single stock options;

·       Enhancements to the Closing Single Price Auction (CSPA) for company sensitive enhancements; and

·       Miscellaneous changes including aligning the times Authorised Signatories are available to the new Session State times, and other changes not related to ASX SR 15 though included to contemporise the rules.

The ASX SR15 changes aim to contemporise the ASX trading platform, introduce operational and technical efficiencies, and reduce complexity. Further detail on the changes follows:

Block and Late Trade reporting simplification – Procedure 3500

Following discussions with participants, ASX has identified an opportunity to simplify trade reporting for Block and Late Trades. These simplifications will reduce the number of trade report codes required to be entered by Participants into the trading platform.

ASIC Market Integrity Rule 6.2.1 (Securities Markets) allows block trades to be executed without pre-trade transparency where the consideration for the transaction is not less than the minimum value for its allocated tier. ASX currently requires that block trades are reported using different trade report codes depending on which tier the instrument is allocated e.g. S1, S2 and S3. In order to simplify the reporting of block trades for equity market products, CGS depository interests and ETFs, these trades will now be reportable to the ASX under a single code ‘SC’. ASX will continue to validate the notional value of the trade against the ASIC Minimum Block Value for the instrument, and reject the trade if required.

Facilitated Special Size Block Special Crossings (FSSBSC) (to be known as Large Principal Transactions (FSSBSC)) will also utilise the ‘SC’ trade report code.

Late Trading

ASX currently requires that Late Trades are reported across seven different Late Trade codes, ASX will be consolidating Late Trade reporting codes to LT and L5 which will help reduce complexity for participants entering these trade reports.

ASX has also taken the opportunity to simplify the rule book across all trade reporting which is not dependent on any technical change. This also includes aligning the name of certain trade reports with the ASIC Market Integrity Rules.

Removal of Open Stagger – Appendix 4013

In 2018, ASX conducted a review of international exchanges, revealing that while there is variation among exchanges regarding the opening procedures, ASX stands alone in maintaining a staggered opening. ASX then consulted the industry, with the majority of respondents expressing support for eliminating the opening stagger.

Opening Single Price Auction (OSPA) Session State – Appendix 4013

ASX is introducing a new Opening Single Price Auction (OSPA) Session State to enable the orderly consumption of the burst of messages during the single opening auction. The OSPA will be randomised, followed by the introduction of a levelling or buffering period before transitioning to continuous trading.

Fixed Open Time for Single Stock Options – Appendix 4013

To provide greater determinism for Market Makers and traders, the opening time for Single Stock Options will be moved from a 30 second random window commencing at 9:59:45 to a ‘fixed’ time of 10:00:05. This guarantees that the options will always open after the underlying equity instruments.

The open time for Index Options will remain unchanged (9:49:45 + random 30 seconds).

Post Close Session State – Appendix 4013

ASX is introducing a new Post Close Session State, this Session State aims to:

·       Enhance liquidity for participants: orders remaining on the lit market at the close price known as ‘surplus quantity’, will be able to execute with new or amended orders at the closing auction price (CSPA); and

·       Facilitate an auction for instruments which had price-sensitive announcements occur during the Pre-CSPA period ensuring all eligible securities can participate in a closing auction.

The Post Close will be applied to the following markets:

·       Equity Markets

·       Warrants

·       Interest Rate Market

Miscellaneous Changes

A number of miscellaneous changes have been made to Procedures including an update to Procedure 3101 regarding Fair and Orderly Markets to ensure that Authorised Signatories of Participants are available to receive communications from the commencement of the OSPA Session State through to the completion of the Post Close Session State.

The marked up changes to the Procedures are attached to this notice for reference.

What do I need to do by when?

Trading Participants should note the changes to the ASX Operating Rule Procedures.

Need more information?

Issued by

Ben Jackson, General Manager, Market Operations

Contact information

Trading Operations
+61 (02)  9256 0677, 1300 655 560
tradingoperations@asx.com.au

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