Optional
This field specifies the first day, and optionally the time, on which any transaction related to the securities on loan is contracted without entitlement to any event related to the securities.
If the ex date is unknown, the following code must be used (Error code(s): T57):
Date must be a valid date expressed as YYMMDD (Error code(s): T50).
Either Date and Time, or Code, but not both, must be present (Error code(s): T62).