Time Message Fields
A Time message is immediately generated and sent when there is a PITCH event for a given clock second. If there is no PITCH event for a given clock second, then no Time message is sent for that second. The Time field is the number of seconds relative to midnight Eastern Time. All subsequent time offset fields for the same unit will use the new Time message value as the base until another Time message is received for the same unit. On C1 Options only and effective 11/02/26 for BZX/EDGX Equities, the Time message also includes the Epoch Time field.
For C1 Options only and effective 11/02/26 for BZX/EDGX Equities, a given trading day may span multiple calendar days. Market data recipients must prepare for a crossing of the midnight ET boundary. At such time, a new Time Reference message will be sent and the Time field in subsequent Time messages will reset to reflect the number of seconds from the most recent midnight ET time.
| Field Name | Offset | Length | Type/(Value) | Description |
|---|---|---|---|---|
| Length | 0 | 1 | Binary | Length of this message including this field |
| Message Type | 1 | 1 | 0x20 | Time message |
| Time | 2 | 4 | Binary | Number of whole seconds elapsed since the start of the current Eastern Time calendar day, derived by converting the current Eastern wall clock time (HH:MM:SS) to seconds. On Daylight Saving Time transition days, Time reflects wall clock seconds and does not adjust for the UTC offset change. On a DST spring-forward day, the maximum value will be 82,799 (23 hours). On a DST fall-back day, values between 3,600 and 7,199 will appear twice. Recipients requiring unambiguous absolute timestamps should use Epoch Time (where available) or Midnight Reference in the Time Reference message. |
| Epoch Time | 6 | 4 | Binary |
|
| Total Length = 6 bytes, 10 bytes for C1 Options Only and effective 11/02/26 for BZX/EDGX Equities | ||||