Symantec DLP (as of v8, 9) uses two tablespaces: USERS and LOB_TABLESPACE. If a customer has performed the 7 to 8 upgrade, there is a possibility that there exists tablespaces called USERS2 and LOB_TABLESPACE2. It is within these two tablespaces and ONLY these two tablespaces that the Symantec DLP "protect" schema is stored.
NOTE: The SYSTEM tablespace is and/or should be reserved for Oracle use only! No other schema objects should be stored there!
See Also: KB 42834: DBA best practice: Avoid creating objects in the SYSTEM tablespace