| 6 | IOI | Optional |
| 7 | Advertisement | Optional |
| 8 | Execution Report | Optional |
| D | New Order Single | Optional |
| E | New Order List | Optional, in group NoOrders (73) |
| G | Order Cancel/Replace Request | Optional |
| J | Allocation Instruction | Optional |
| R | Quote Request | Optional, in group NoRelatedSym (146) |
| S | Quote | Optional |
| V | Market Data Request | Optional, in group NoRelatedSym (146) |
| W | Market Data Snapshot Full Refresh | Optional, in group NoMDEntries (268) |
| X | Market Data Incremental Refresh | Optional, in group NoMDEntries (268) |
| AA | Derivative Security List | Optional, in group NoRelatedSym (146) |
| AB | New Order Multileg | Optional |
| AC | Multileg Order Cancel/Replace | Optional |
| AE | Trade Capture Report | Optional |
| AG | Quote Request Reject | Optional, in group NoRelatedSym (146) |
| AI | Quote Status Report | Optional |
| AJ | Quote Response | Optional |
| AK | Confirmation | Optional |
| AL | Position Maintenance Request | Optional |
| AM | Position Maintenance Report | Optional |
| AN | Request For Positions | Optional |
| AO | Request For Positions Ack | Optional |
| AP | Position Report | Optional |
| AR | Trade Capture Report Ack | Optional |
| AS | Allocation Report | Optional |
| AW | Assignment Report | Optional |
| AX | Collateral Request | Optional |
| AY | Collateral Assignment | Optional |
| AZ | Collateral Response | Optional |
| BA | Collateral Report | Optional |
| BB | Collateral Inquiry | Optional |
| BG | Collateral Inquiry Ack | Optional |
| BK | Security List Update Report | Optional, in group NoRelatedSym (146) |
| BM | Allocation Instruction Alert | Optional |
| BP | Security Definition Update Report | Optional |
| BQ | Settlement Obligation Report | Optional, in group NoSettlOblig (1165) |
| BR | Derivative Security List Update Report | Optional, in group NoRelatedSym (146) |
| BU | Market Definition | Optional |
| BV | Market Definition Update Report | Optional |
| CJ | Margin Requirement Report | Optional |
| DC | Trade Match Report | Optional, in group NoInstrmtMatchSides (1889) |
| DF | Party Risk Limit Check Request | Optional |
| DG | Party Risk Limit Check Request Ack | Optional |
| DL | Position Transfer Instruction | Optional |
| DN | Position Transfer Report | Optional |
| DP | Market Data Statistics Report | Optional |
| DW | Trade Aggregation Request | Optional |
| b | Mass Quote Ack | Optional, in group NoQuoteEntries (295) |
| c | Security Definition Request | Optional |
| d | Security Definition | Optional |
| e | Security Status Request | Optional |
| f | Security Status | Optional |
| i | Mass Quote | Optional, in group NoQuoteEntries (295) |
| k | Bid Request | Optional |
| m | List Strike Price | Optional, in group NoStrikes (428) |
| s | New Order Cross | Optional |
| t | Cross Order Cancel Replace Request | Optional |
| x | Security List Request | Optional |
| y | Security List | Optional, in group NoRelatedSym (146) |
| z | Derivative Security List Request | Optional |