The type of identification taxonomy used to identify the security.
I
=
ISIN or Alternate instrument identifier plus CFI
Identified through use of SecurityID(48) and SecurityIDSource(22) of ISIN or another standard source plus CFICode(461).
Added EP179
[ISINOrAltInstrmtID]
E
=
Interim Taxonomy
Identified through use of AssetClass(1938) plus either Symbol(55) or SecurityID(48) and SecurityIDSource(22), and/or other additional instrument attributes.