From the CME exchange concerning UDS deletions in Eurodollar Options:
CME Group will be deleting all User-Defined Spread Instruments (UDS) on CME Eurodollar Options Market Segment 50 and NYMEX / COMEX Options Market Segment 56 during today’s maintenance window, 6/6/2019. Any UDS with resting GT orders will not be deleted.
As a reminder, UDS instruments can be deleted midweek. When this occurs, CME Globex sends a Security Definition message (tag 35=d) with the instruction to delete the instrument with tag 980-SecurityUpdateAction=D (delete).
A tag 48-SecurityID value from a deleted instrument can be reassigned to a newly listed instrument within the same week; therefore, CME Group strongly recommends the client system process the Security Definition message with the tag 980=D as received.
If you have any questions, please contact the CME Global Command Center in the U.S. at +1 800 438 8616, in Europe at +44 20 7623 4747 or in Asia at +65 6532 5010.
The sender provided the following contact information.
Sender’s Name: CME Global Command Center
Sender’s Email: firstname.lastname@example.org
Sender’s Contact Phone: 1800 438 8616
If you no longer wish to receive Customer Advisories, please Unsubscribe.