|  | 8 | BeginString |  | FIX.4.2 (Always unencrypted, must be first field in message) |  | 
|  | 9 | BodyLength |  | (Always unencrypted, must be second field in message) |  | 
|  | 35 | MsgType |  | (Always unencrypted, must be third field in message) |  | 
|  | 49 | SenderCompID |  | (Always unencrypted) |  | 
|  | 56 | TargetCompID |  | (Always unencrypted) |  | 
|  | 115 | OnBehalfOfCompID |  | Trading partner company ID used when sending messages via a third party (Can be embedded within encrypted data section.) |  | 
|  | 128 | DeliverToCompID |  | Trading partner company ID used when sending messages via a third party (Can be embedded within encrypted data section.) |  | 
|  | 90 | SecureDataLen |  | Required to identify length of encrypted section of message. (Always unencrypted) |  | 
|  | 91 | SecureData |  | Required when message body is encrypted. Always immediately follows SecureDataLen field. |  | 
|  | 34 | MsgSeqNum |  | (Can be embedded within encrypted data section.) |  | 
|  | 50 | SenderSubID |  | (Can be embedded within encrypted data section.) |  | 
|  | 142 | SenderLocationID |  | Sender's LocationID (i.e. geographic location and/or desk) (Can be embedded within encrypted data section.) |  | 
|  | 57 | TargetSubID |  | "ADMIN" reserved for administrative messages not intended for a specific user. (Can be embedded within encrypted data section.) |  | 
|  | 143 | TargetLocationID |  | Trading partner LocationID (i.e. geographic location and/or desk) (Can be embedded within encrypted data section.) |  | 
|  | 116 | OnBehalfOfSubID |  | Trading partner SubID used when delivering messages via a third party. (Can be embedded within encrypted data section.) |  | 
|  | 144 | OnBehalfOfLocationID |  | Trading partner LocationID (i.e. geographic location and/or desk) used when delivering messages via a third party. (Can be embedded within encrypted data section.) |  | 
|  | 129 | DeliverToSubID |  | Trading partner SubID used when delivering messages via a third party. (Can be embedded within encrypted data section.) |  | 
|  | 145 | DeliverToLocationID |  | Trading partner LocationID (i.e. geographic location and/or desk) used when delivering messages via a third party. (Can be embedded within encrypted data section.) |  | 
|  | 43 | PossDupFlag |  | Always required for retransmitted messages, whether prompted by the sending system or as the result of a resend request. (Can be embedded within encrypted data section.) |  | 
|  | 97 | PossResend |  | Required when message may be duplicate of another message sent under a different sequence number. (Can be embedded within encrypted data section.) |  | 
|  | 52 | SendingTime |  | (Can be embedded within encrypted data section.) |  | 
|  | 122 | OrigSendingTime |  | Required for message resent as a result of a ResendRequest. If data is not available set to same value as SendingTime (Can be embedded within encrypted data section.) |  | 
|  | 212 | XmlDataLen |  | Required when specifying XmlData to identify the length of a XmlData message block. (Can be embedded within encrypted data section.) |  | 
|  | 213 | XmlData |  | Can contain a XML formatted message block (e.g. FIXML). Always immediately follows XmlDataLen field. (Can be embedded within encrypted data section.) See Appendix M – FIXML Support |  | 
|  | 347 | MessageEncoding |  | Type of message encoding (non-ASCII characters) used in a message’s "Encoded" fields. Required if any "Encoding" fields are used. |  | 
|  | 369 | LastMsgSeqNumProcessed |  | The last MsgSeqNum value received and processed. Can be specified on every message sent. Useful for detecting a backlog with a counterparty. |  | 
|  | 370 | OnBehalfOfSendingTime |  | Used when a message is sent via a "hub" or "service bureau". If A sends to Q (the hub) who then sends to B via a separate FIX session, then when Q sends to B the value of this field should represent the SendingTime on the message A sent to Q. (always expressed in UTC (Universal Time Coordinated, also known as "GMT") |  |