Time Reference Message Fields (Effective 11/02/26 on BZX and EDGX)
The Time Reference message is used to provide a midnight reference point for recipients of the feed. It is sent whenever the system starts up and when the system crosses a midnight boundary. All subsequent Timestamp values will use the last Midnight Reference until another Time Reference message is received. The Time Reference message includes the Trade Date, so most other sequenced messages will not include that information.
The Time Reference message will be sent when the system first detects a message that crosses a midnight boundary. In the event a message from another internal data source has not yet passed midnight and needs to be sent, a negative Timestamp will be used to reflect that the time for that message is prior to midnight.
The Timestamp field will contain the offset from the Trade Date of the Time Reference message.
Time Reference messages will be included in a spin response.
| Field Name | Offset | Length | Data Type | Description |
|---|---|---|---|---|
| Message Type | 0 | 1 | T | Time Reference message |
| Timestamp | 1 | 8 | Timestamp | Timestamp |
| Midnight Reference | 9 | 10 | Numeric | Midnight Eastern Time reference time for subsequent Timestamp values, expressed as number of whole seconds since the Epoch (Midnight January 1, 1970 UTC). |
| Time | 19 | 10 | Numeric | 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 Midnight Reference in the Time Reference message. |
| Trade Date | 29 | 8 | Numeric | Current Trade Date as represented by YYYYMMDD |
| \n | 37 | 1 | \n | End of message |