This would certainly suck. It's hard enough to get jobs as it is, but to get a new job only to have your former employer show up and say "nuh-uh"?

I can understand why Seagate is nervous - leaving one company for a competitor and then using confidential info at the competitor unfortunately happens all the time. But to assume that someone is going to do this is kinda unfair; it's not just assuming they're guilty until proven innocent, but assuming they're guilty before they've even had a chance to do something wrong. This is why we have non-disclosure agreements (NDAs) - to put someone under contractual and legal obligation not to do this. That doesn't stop it from happening, of course, but that doesn't mean you can automatically do what Seagate is trying to do. If he does do something illegal (which probably wouldn't be that hard to prove), then you go after people, but not before.