The bottom line is that you probably can&#x27;t ensure it&#x27;s deleted.<p>Consider this: I have at least two backup mechanisms I use regularly (Dropbox, Time Machine) and I don&#x27;t even think about them at this point. Even if you watched him delete it, it&#x27;s pretty likely that data already exists outside of his laptop, if he&#x27;s even reasonably diligent about his machine.<p>So you&#x27;re left with a few options:<p>* Trust<p>If you&#x27;re firing him for a good reason, and can validate that reason in <i>his</i> mind, you can choose to trust that he won&#x27;t be a douche<p>* Trust with seeds<p>Before firing make sure the data has something uniquely traceable to him. Data that only his export gets; dummy users, dummy data, something steganographic so if your trust is violated you can identify the breach source.<p>Your options are limited, AFAICT. Once data exists in the wild it&#x27;s essentially impossible to maintain any semblance of control. Your only real hope is that he&#x27;s honorable. Even in the worst of circumstances I&#x27;d never breach trust in that way.<p>Especially when there are much more insidious, passive-aggressive, entertaining ways to bring down a company.