SYSAUX tablespace

see an aud$ table in sysaux tablespace ?
if so then auditing is switched on and still in sysaux tablespace.

it has to be moved to a different tablespace to be able to purge it
see here for a very detailed explanation
http://www.oracle-base.com/articles/11g/auditing-enhancements-11gr2.php

you could also set the purging policies to get rid of the old data in oem
http://docs.oracle.com/cd/E24628_01/doc.121/e24473/repository.htm#sthref572

allthough that might not retrieve the used tablespace

Thanks for the quick response.
These are the top 10 objects in SYSAUX:

OWNER,SEGMENT_NAME,SEGMENT_TYPE,MB
SYS,SYS_LOB0001391512C00038$$,LOBSEGMENT,1446
SYS,WRH$_ACTIVE_SESSION_HISTORY,TABLE PARTITION,1223
SYS,WRH$_SQL_PLAN,TABLE,1088
SYS,WRH$_SYSMETRIC_HISTORY,TABLE,1014
SYS,WRH$_SYSMETRIC_HISTORY_INDEX,INDEX,627
SYS,WRH$_SYSMETRIC_SUMMARY,TABLE,621
SYS,WRH$_SYSSTAT_PK,INDEX PARTITION,536
SYS,SYS_LOB0001388926C00007$$,LOBSEGMENT,428
SYS,WRH$_BG_EVENT_SUMMARY,TABLE,381
SYS,WRH$_SYSSTAT,TABLE PARTITION,364

the most of the objects is  OEM, AWR ,ASH  and LOB related objects. A LOB segment stores data for a CLOB/BLOB table column.

Bad news:
- AWR cannot be completely turned off
- *Any* manipulation of AWR data needs appropriate (paid) licenses (not included in Enterprise Edition)
- AWR snapshot size will grow over time (this is a known issue) so even deleting old snapshots is not a final solution, because the snapshot will eventually reach the size where only one snapshot fits.

Good news:
- AWR data is not needed for everyday operation, nor for mere mortals like DBAs, only for Oracle Support Requests. (you are allowed to provide them requested AWR information even if you don't have the license)
- Oracle handles the case when SYSAUX is full with no problems. In worst case some AWR stuff will fail. So what.

So you should apply two measures:
- ensure that SYSAUX tablespace is limited in size (e.g. current size + 10% would do)
- modify your DB free space checking tools so that they don't raise alarms on SYSAUX tablespace being 100% full.

That's the trap everyone falls into
this is not true
(you are allowed to provide them requested AWR information even if you don't have the license)

it's stated in the license that support will ask your for AWR data because they are oblivious to what you are entitled to by your license
it's up to you (the dba) to know if you are licensed to that

after that the license people come in: i see you use AWR but aren't license for it
here's your extra fee you need to pay

so be careful with that

Well we are more foxy than that.

Oracle Support: "Please send AWR Reports"
Me: "I'm sorry but we don't have the necessary licenses."
Oracle Support: "That's no problem, Sir. Please send them."

Once we have it written in an email Oracle shouldn't complain, maybe they should subtract the license fee from the annual bonus of that given support expert. :P

Thank you guys for the help. Do you guys have any insight as to how best to remove AWR data?

Thank you all for your feedback. I have enough info to proceed.