Organisational

Maker/Taker-agnostic: The Venue always dictates the supported message flow, the API does not make any assumptions about counterparty roles, eliminating the need for separate Maker and Taker Whisperer APIs/builds/installations.

Market Data

Explicit identification of "Pre-Open" status (to assist allowing for backwardated prices)
LotSize

Product Types

All FX product types supported:

FX Spot
FX Forward
FX Non-Deliverable Forward - Fixing date and reference now supported.
FX Swap
FX Non-Deliverable Swap
FX Block
Future

Regulatory Fields

Full Regulatory field pass-through - all explicitly supported at Body, Leg and Allocation levels, for all message types through the trade lifecycle. Market Mid Price, LEIs, flags, regulatory trade IDs etc for:

SEF
EMIR
MiFID II

Counterparties

Counterparty Firm/LEI/Trader details now provided via Parties block.

Quotation Trading Models

Full support for ESP and RFQ/RFS models:

Pre-trade allocations.
Order messages linked with QuoteReqID to assist supportability.
Indicative/Tradeable QuoteType (aka Quote condition) now supported, to allow Maker ESP/RFS quote withdrawal.

Orders

Additional Time In Force support:

GTD (Good 'til Date) - timestamp of desired order expiry (within current trading day).
GFT (Good For Time) - number of seconds before order expiry

Additional Order types:

Iceberg
Pegged
Discretion
Trailing Stop (to double check).

Cancel/replace now allows for provision of MinQty and StopPx.

REMOVED

Software Limit Monitor

Whilst the SLM remains a component of Whisperer 3.13/14, in MFSBE4 SLM API support is now deprecated in favour of our clients using Reflector, or at least using the same notification interface as used by Reflector (WHSPRR-1676):

TradeLimitDataMessage
LockUserMessage
LockResponseMessage

MFSBE4 Business Changes