U.S. Options

As previously announced in the March 30, 2026 and July 21, 2026 Alerts, the MIAX Options Exchange will implement the below functionality enhancements.

Additionally, the following change will be made which was not previously announced:

1. Auction Start Price for PRIME and cPRIME auctions will no longer be disseminated (i.e. will always be 0) via the AIS Feed
   1. This change impacts Simple and Complex Liquidity Seeking Event Notifications with Event Type “P”.
   2. All other Simple and Complex Liquidity Seeking Event Notifications are unchanged.
   3. See below for roll out schedule.

An updated Administrative Information Subscriber (“AIS”) Interface Specification (v2.6a) has been posted to the MIAX website to support this change AIS v2.6a.

Updated Implementation Schedule for All Enhancements:

1. For detailed descriptions of all functionality that was previously announced, please refer to the July 21, 2026, alert.
2. MEI v2.11 Changes
   1. Friday, September 4, 2026
      1. Quote Width Relief Notification Functionality
      2. Mass Cancel Trigger Reason on Line Disconnect
   2. Friday, September 11, 2026
      1. Selective Liquidity Auto Purge (SLAP) Functionality
      2. Aggregate Risk Manager (ARM) Origin Multiplier Functionality
   3. All MEI v2.11 features require a certification.
3. AIS v2.6a Changes
   1. Updates:
      1. New “Origin” field in both Simple and Complex Liquidity Seeking Event Notifications
      2. PRIME and cPRIME Auction Start Price will no longer be disseminated (described earlier in this alert)
   2. Roll out schedule will be cloud by cloud:
      1. Day 1 - Tuesday, September 1, 2026: Cloud 21  
      2. Day 2 - Wednesday, September 2, 2026: Clouds 18 – 20
      3. Day 3 - Thursday, September 3, 2026: Clouds 1 – 8
      4. Day 4 - Friday, September 4, 2026:  Clouds 9 – 17 and 22 – 24

  Additional Details:

1. These new features are pending SEC approval.
2. These changes will be available in the MIAX Options Exchange's Firm Test Bed (FTB2) environment starting July 31, 2026.
3. Visit MIAX Options Interface Specifications for additional details.

 
Please contact MIAX Trading Operations at TradingOperations@miaxglobal.com or (609) 897-7302 to discuss any specific issues, update configurations and to arrange interface testing.