If you quit Dec 31, and the company usually pays out annual bonuses on Jan 30, don't expect a check.
Pretty clear cut for me. The conditions were met, they owe him $10k. Maybe not legally but certainly morally.
Of course it did. Quote from the article:
the payout was contingent on said employee staying for a minimum of a 6 month period at the position
If that's the really the full text of the agreement (which seems plausible to me, I've seen similar e-mails) then there is nothing unclear about that. Even if he had quit immediately after referring that other guy he'd still get the bonus. Period.
well established practice.
Certainly not around here.
(The company was Google, which should qualify as an American company even though this happened in Europe. I can't imagine there being any particular Swiss legislation that would have affected this case.)
It's more like that you had a personal bonus scheduled for Dec 31, and your last day was the next Jan 30, and they never paid you.
Fail for Miso.