Revision History
| Document Version | Date | Description |
|---|---|---|
| 1.0.0 | 05/09/11 | Initial version. |
| 1.0.1 | 06/06/11 | Various changes based on feedback and internal discussions. |
| 1.0.2 | 06/27/11 | Minor formatting update. |
| 1.0.3 | 07/12/11 | Corrected typo in Multicast Configuration section. |
| 1.1.0 | 09/26/11 | Converted protocol specification from Multicast format to TCP format. |
| 1.2.0 | 02/19/16 | Bats branding/logo changes. |
| 1.2.1 | 03/24/16 | Update to Auction Update dissemination times for Opening and Closing Auctions (effective 3/4/16). |
| 1.2.2 | 10/17/17 | Cboe branding/logo changes. |
| 1.3.0 | 07/03/18 | Added support for Cboe Market Close (CMC) in Auction Update and Auction Summary. Auction Update messages effective TBD. |
| 1.3.1 | 01/30/20 | Added effective date for CMC, 3/6/20. |
| 1.3.2 | 07/14/21 | Removed effective date for CMC (effective 3/6/20). |
| 1.3.3 | 06/16/22 | Updated title to Cboe BZX Equities and added verbiage to note Cboe Market Close Behavior. |
| 1.3.4 | 02/16/23 | Updated the Auction Update dissemination time to approximately 3:49 p.m. ET for any symbol with crossed Cboe Market Close shares (effective 03/10/23). |
| 1.3.5 | 03/15/24 | Added extended versions of the Auction Update and Auction Summary messages (effective 06/17/24). |
| 1.3.6 | 11/13/24 | Updated Auction Update message to indicate that an Auction Update message will be disseminated after each matching session is complete (effective 01/31/25). |
| 1.3.7 | 01/15/25 | Updated with Cboe Titanium branding. |
| 1.3.8 | 04/21/25 | Cboe will disseminate Cboe Closing Auction information every 5 seconds between 3:00 and 3:59 p.m. every 1 second between 3:59 and 4:00 p.m. for the Closing Auction (effective 06/06/25). |
| 1.3.9 | 09/09/26 | Updated Introduction to reflect changes to opening auction process (effective 10/05/26). |