C1
Either field 39A or 39B, but not both, may be present (Error code(s): D05).
C2
When used, fields 42C and 42a must both be present (Error code(s): C90).
C3
Either fields 42C and 42a together, or field 42M alone, or field 42P alone may be present. No other combination of these fields is allowed (Error code(s): C90).
C4
Either field 44C or 44D, but not both, may be present (Error code(s): D06).
C5
Either field 52a "Issuing Bank" or field 50B "Non-Bank Issuer", but not both, must be present (Error code(s): C06).
