A year ago I quit my job and went fulltime with my startup, but before quitting I met some wonderful people at the company I worked for.
And I'd love to invite one of them to work with me, but I felt this is kinda improper to entice somebody from my ex-employer...
But now I heard that this person is quitting anyway. He got bored, sick, tired and pissed off by his job, so I made my offer that he accepted.
I've sent a polite notice to my ex-boss which read: "just so you know, I've sent an offer to one of your people who's quitting anyway, JFYI, hope thats OK" and he totally lost his temper.
He called us traitors and insists I cancel my offer, because this is a threat to his company, because his staff "should not know they have a choice to work for YOU when they quit my company!". So I'm kinda confused... We never signed any "non-compete" agreements, nor promised anything like this verbally, so I guess we're not doing anything wrong right?
I think you need to think through things before acting on your nice-guy impulses. You have definitely ruined your relationship with your ex-boss for no good reason.
At this point you want to keep your guy and not have your former boss sue you over it (even if you have a strong case he will make you sink money in legal costs, so avoid court if you can). You can do this by convincing your former boss that your new guy did not know about his options until after he quit. Don't get into a wrestling match with him, even if you are right.
Good luck!