MassCancelOrderUSOptionsV1 Message Fields
| Field Name | Offset | Length | Data Type | Description |
|---|---|---|---|---|
| StartOfMessage | 0 | 2 | Binary | 0xB0 0xE3 |
| MessageLength | 2 | 2 | Binary | |
| MessageType | 4 | 2 | Binary | 0x07DF (2015) |
| MatchingUnit | 6 | 1 | Binary | Zero - from member message |
| Reserved | 7 | 1 | Binary | MUST be zero from member |
| SequenceNumber | 8 | 4 | Binary | Next sequence number (or zero) |
| MassCancelID | 12 | 20 | Text | |
| ClearingFirm | 32 | 4 | Alpha | |
| RoutingFirmID | 36 | 4 | Alpha | |
| RiskRoot | 40 | 6 | Text | |
| MassCancelInst | 46 | 8 | Text | |
| SendTime | 54 | 8 | DateTime | |
| ScratchPad | 62 | 2 | Binary |





