No longer used as of FIX 4.3. Included here for reference to prior versions.
*** REPLACED FIELD - See: Appendix 6-F: 3. Replaced Fields: ExecBroker, BrokerOfCredit, ClientID(tag 109), ClearingFirm, ClearingAccount, and SettlLocation [replaced in FIX 4.3] ***
Firm identifier used in third party-transactions (should not be a substitute for OnBehalfOfCompID <115>/DeliverToCompID <128>).