On May 27, 2022, MEMX released new minor versions of its MEMO FIX 1.9 and 1.10 specification to correct a typo. Version 1.9 Rev A and 1.10 Rev A include the following correction and can be downloaded here:
Section 6.3 Logon initially identified DefaultCstmApplVerID as Tag 1480, but should have been identified as 1408.
Our Market Operations and Member Experience teams are here for any of your questions.
MEMX Market Operations
MEMX Member Experience