One of our integrations attempted to insert a Contact record with a value for LastName = ????? (yes - five question marks).
SFDC failed the insert (before any trigger executed) with:
FIELD_INTEGRITY_EXCEPTION, Last Name: You must enter a valid value: [LastName] I duplicated the error by entering a Contact into the UI with LastName = ?????
LastNames of ?, ??, ???, ????, ?????? and ??????? pass, only LastNames with five question marks fail
