NULL as a valueIssue According to ServiceNow documents using the string NULL in a field value is not expected. It results in clearing the field. The string NULL has a particular role in scripts and is a reserved word. The reserved word is NULL in all capital letters. ServiceNow document link What happens when usernames or any data contains "NULL"? Can this be allowed? What is recommended for instances where data brought into an instance contains "NULL"? A field with the value Null or null, for example, is acceptable but please note "null" and "Null" may create issues when querying for these values.Review KB1543644 for more details: KB1543644ReleaseAnyCauseThe string "NULL" is used throughout the platform to denote an empty value. Even if we could get the string "NULL" in the Last Name field, you could never query for it, filter by it on a list, etc. Because all other areas of the platform will interpret "NULL" as you intend to search on empty values.ResolutionThe only recommendation is to append some special character to users that have the last name of "NULL". Maybe adding a space to the end or an underscore.