Synchronization of Business Clocks

Synchronization of business clocks refers to the trading venue’s obligation to keep the business clocks that they use to record the date and time of any reportable event, synchronized with the Coordinated Universal Time (UTC).


Accordingly in MiFID II, operators of trading venues shall ensure that their business clocks adhere to the levels of accuracy outlined in the following table.

Finally, operators of trading venues shall establish a system of traceability to UTC.

Gateway-to-gateway latency time of the trading system

UTC Accuracy
(Maximum divergence from UTC)

(timestamp precision)

> 1 ms

1 millisecond

1 millisecond or better

≤ 1 ms

100 microseconds

1 microsecond or better

Our Approach

To be compliant with EU provisions, SIX Swiss Exchange will implement the more accurate time synchronization protocol (PTP – Precision Time Protocol) with special PTP-compliant hardware on our INET infrastructure which has gateway-to-gateway latency of less than one millisecond. PTP provides an accuracy of 1-3µs and will be compliant with RTS 25.

For all our interfaces which have gateway-to-gateway latency of more than one millisecond (FIX, file and GUI based), the format of timestamp attributes is adapted to support up to microsecond precision values.

Interface impact
On-book matcher (X-Stream INET) can be accessed via  2 main interfaces:  

DTI (OTI and QTI):    

  • There is no change foreseen in OTI/QTI (and also IMI) because these interfaces already provide timestamp granularity in microseconds (technically even in nanoseconds).


  • STI interface will technically change for all STI messages; functionally for O&E, Confirmation, Trade Reporting.
  • There are session level changes in all STI messages (O&E, Confirmation, Trade Reporting)
    -    Inbound: For “SendingTime” SWXess will accept up to microsecond precision value
    -    Outbound: “SendingTime” will be in mllisecond precision
  • There are application level changes in STI (O&E) and other STI services (Confirmation, Trade Reporting)
    -    Inbound: SWXess will accept up to microsecond precision value (for all STI messages)
    -    Outbound: SWXess will  populate “TransactTime” and/or “TrdRegTimestamp” with up to microsecond precision value

Note that for SIX Swiss Exchange Liquidnet Service, the Inbound microsecond timestamp is truncated to millisecond precision if needed.

FDC interface will see both technical and functional changes

  • Similar to the STI messages

The outlined approach is believed to be aligned to the principles of EU law.
Implementation with SMR7 (2017).

Swiss Regulation

European Regulation