Background

ExecutionAcknowledgement/ 35=BN is commonly supported by most ECNs to ACK or NACK a client's ExecutionReport.It is considered the end of the order life cycle in the maker workflow, where Whisperer clients are the market makers.

However, Integral is an anomaly and does not send an ExecutionAcknowledgement to notify the client that their ExecutionReport is Accepted or Rejected.

To normalise the order lifecycle in the maker workflow, MarketFactory will introduce a synthetic ExecutionAcknowledgement in the maker gateways, where the venue API does not support the message.

Affected Venues

• integral_esp_maker
• integral_rfs_maker

Change

To address a normalisation gap in the maker workflow order lifecycle, MarketFactory will introduce a synthetic ExecutionAcknowledgement, in the absence of a venue ACK in response to our client's ExecutionReport.

Timeline

• 25 Jul 2025 - UAT - MarketFactory will introduce the synthetic ExecutionAcknowledgement for clients to test the affected venues in UAT.
• 15 Aug 2025 - PROD - Whisperer release 2025.08.XX.WE to expose the synthetic ExecutionAcknowledgement change in PROD.

A synthetic ExecutionAcknowledgement will not be sent to the client in the following scenarios:

• Whisperer gateway received a replayed ExecutionReport from a client with PossDupFlag = Y during the recovery/ replay at session synchronisation.
• Integral did not receive the client ExecutionReport by the end of the preconfigured OrderTimeout interval. In this scenario, the client will receive an OrderTimeout/ 35=OT.
• The client sent an ExecutionReport after it received an OrderTimeout. In this scenario, the client will receive an ExecutionAcknowledgement with IsSynthetic flag set to N.