From FIXwiki

FIX Message MarketDefinition (MsgType=BU)

MsgType	FIX Specification	First introduced	Deprecated
MsgType=BU	PreTrade messages - MarketStructureReferenceData	FIX.5.0

The Market Definition message is used to respond to Market Definition Request. In a subscription, it will be used to provide the initial snapshot of the information requested. Subsequent updates are provided by the Market Definition Update Report.

This message is associated with a list of trading sessions (and subsessions) applicable for the segment - the list is published using the Trading Session List message.

Message Contents By FIX Version

Notes

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