From FIXwiki

FIX Message SecurityDefinitionRequest (MsgType=c)

MsgType	FIX Specification	First introduced	Deprecated
MsgType=c	PreTrade messages - SecuritiesReferenceData	FIX.4.2

The Security Definition Request message is used for the following:

1. Request a specific Security to be traded with the second party. The request security can be defined as a multileg security made up of one or more instrument legs.

2. Request a set of individual securities for a single market segment.

3. Request all securities, independent of market segment.

Subscription for security status can be optionally specified by including the SubscriptionRequestType[263] field on the message.

Message Contents By FIX Version

Notes

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