Have you confronted him about the fact that it's probably not a good idea that he has this data on his personal laptop? How did the data end up there in the fir

Have you confronted him about the fact that it's probably not a good idea that he has this data on his personal laptop? How did the data end up there in the first place? Why doesn't he have a work laptop? How long have you known/how did you learn? Has it maybe been a "public secret" for a while, and you tacitly accepted it? If so, you probably can't fire him for it. "Hey, dude, it struck me the other day that it's a pretty bad risk for the company that you have that database on your personal laptop -- do me a favour, pick out a top-of-the-line ThinkPad/MBP, expense it, and put the DB on an encrypted volume -- and make sure you delete the DB from your laptop and any backup you have. Thanks, man!"