Prevention is better than cure, but with budget cuts that creates the challenge. Audits are more common place now and someone will come knocking eventually so it’s running the risk at your own peril if you do not do something. It’s not advisable to bury your heads in the sand and do make sure the SLT are aware of the current situation. As mentioned by someone earlier Software Licensing is a black art and certainly just knowing what licenses are installed will still not be enough, you need to show the paper trail, Invoice, EULA and demonstrate its installed on the right machine to fully reconcile the information to stave off an audit.