From FIXwiki

FIX Message SecurityList (MsgType=y)

MsgType	FIX Specification	First introduced	Deprecated
MsgType=y	PreTrade messages - SecuritiesReferenceData	FIX.4.3

The Security List message is used to return a list of securities that matches the criteria specified in a Security List Request.

Message Contents By FIX Version

Notes

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