We had one small installation of Oracle on a VM running some old legacy database. Oracle audited and noted that the default packages were installed. The poor DBA didn't realise he was supposed to remove all of the default install-time packages as we had only licensed the base installation, but despite the fact we were only actually using the base packages, Oracle kindly notified us we were under licensed and owed money for several years with all the out-of-the-box features. Also because we were running oracle on a small 1vCPU Virtual machine, we had licensed for 1 CPU, but Oracle doesn't recognise "soft partitioning" hypervisor like ESX, only Oracle VM or "Hard Partitioning"... so we also got hit up for the full count of CPUs on the underlying ESX host (8!). After a lot of wrangling, Legal departments going back and forth we made a deal and purchased double the licensing we actually needed (so they had a sale and we were out of pocket for software we will never use).
Needless to say, we have since divested in Oracle and will never use their products again.
Oh, that reminds me. Oracle Java is a pain in the arse now, and the sooner it dies the better.