MIAX Options Exchange: Interface Specification Updates For Upcoming Features

The MIAX Options Exchange has published updated Interface Specifications to support the following upcoming changes:

Complex Orders - Auction on Arrival Only (AOAO):

FIX Interface Specification (FOI) - Version 2.5
- Updated New Order –Multileg (MsgType = "AB") to support AOAO
  - Added new FIX Value “O” = Auction on Arrival Only to FIX Tag MIAXExecInst (#9018)
- Updated Execution Report (MsgType = "8") to support AOAO
  - Added new FIX Value “O” = Auction on Arrival Only to FIX Tag MIAXExecInst (#9018)
FIX Drop Specification (FXD) – Version 2.5
- Updated Execution Report (MsgType = "8") to support AOAO
  - Added new FIX Value “O” = Auction on Arrival Only to FIX Tag MIAXExecInst (#9018)

Complex Orders - cPRIME Last to Fill:

FIX Interface Specification (FOI) - Version 2.5
- Updated New Order Cross – Multileg (MsgType = "As") to support Last to Fill
  - Added new FIX Tag “ExecInst” (#18) with FIX Value “X” = Last to Fill

Complex Orders - Attributable support:

MIAX Order Feed Interface Specification (MOR) – Version 2.5
- Updated Complex Order Message (Message Type = “R”) to support Attributable
  - Added Attributed ID Field
FIX Interface Specification (FOI) - Version 2.5
- Updated New Order –Multileg (MsgType = "AB") to support Attributable
  - Added new FIX Tag “AttributableOrderIndicator” (#9732) to support Attributable

Complex Orders – Related Futures Cross (RFC):

FIX Interface Specification (FOI) - Version 2.5
- Updated New Order Cross – Multileg (MsgType = "As") to support Related Future Cross (RFC).
  - Added new FIX Value “8” = RFC to FIX Tag CrossType (#549)
  - Repeating Group FIX Tags “NoOrders” (#73), “NoAllocs” (#78), and “CustomerOrFirm” (#204) will apply to RFC
- Updated Execution Report (MsgType = "8") to support Related Future Cross (RFC)
  - Added new Position 28 Value "R" = RFC to FIX Tag AdditionalBillingParameters (#9730)
CTD Interface Specification (CTD) – Version 2.5
- Updated Trade Message (Message Type = “T”) to support Related Future Cross (RFC)
  - Added field value "R" = RFC to Strategy State Field
FIX Drop Specification (FXD) – Version 2.5
- Updated Execution Report (MsgType = "8") to support Related Future Cross (RFC)
  - Added new Position 28 Value "R" = RFC to FIX Tag AdditionalBillingParameters (#9730)

Simple Orders - ISO PRIME:

Top of Market Feed (ToM) – Version 2.4
- Updated Last Sale Message (Message Type = “T”) and Trade Cancel Message (Message Type = “X”) to support ISO Prime
  - Added new Trade Condition “b” Trade from a ISO Paired PRIME transaction
FIX Interface Specification (FOI) - Version 2.5
- Updated New Order Cross – (MsgType = "s") to support ISO Prime
  - Added new FIX Value "f" = Inter-market Sweep Order (ISO) to FIX Tag ExecInst (#18)
CTD Interface Specification (CTD) – Version 2.5
- Updated Trade Message (Message Type = "T") to support ISO Prime
  - Added new Trade Condition “b” Trade from a ISO Paired PRIME transaction

New MEI Bulk Quote Message – MIAX Express Interface (MEI):

EI Interface Specification (MEI)
- New Simple Bulk Quote Message Type “qq” with increased size
  - Increased *Reserved* size to 32 Bytes for future use
  - Existing “qm” Simple Bulk Quote Message Type will be deprecated

The changes to MEI are mandatory. All other changes are optional.

Key Dates:

These features will be available in Firm Test Bed (FTB2) starting November 13, 2020
These features are anticipated to be activated in production in January 2021 (pending SEC approval)

Please review the updated interface specifications for further details:

MIAX Options Exchange Specifications

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