There really is no practical way to "make sure" they delete anything. They could have seen the writing on the wall weeks ago and smuggled code out. If I was b

There really is no practical way to "make sure" they delete anything. They could have seen the writing on the wall weeks ago and smuggled code out. If I was bringing my own laptop into a job, and they fired me and wanted to see what was on my laptop, the response I'd give them is "show me a court order." This is one of the reasons why it is a good idea to provide your employees with the equipment they need to do the job. If it is their laptop, then you do not have the right to go snooping around in it, you pretty much (absent prior written agreement) have to take their word that they have or will delete anything proprietary.