The login and user is SDECREATOR. It owns tables and other objects. In TOAD for SQL Server they connect as SDECREATOR. They can see their objects. They granted SELECT to a user MAPVIEW. However, the permissions tab is blanks.
To take that one step further I was able to reproduce this in SSMS as that user. As a user with sysadmin I can see the permissions granted, but as SDECREATOR the Properties --> Permissions is blank.
SDECREATOR is a sql login, and it is a user in the database and a schema. It creates objects, and then grants SELECT to other users to VIEW the data.
I haven't confirmed this part yet, but these databases have a 3rd party software ArcGIS from ESRI installed into them. SDECREATOR creates features classes and its geodatabase elements. I need to confirm that just creating a simple single table is the same.