Multiple news outlets are reporting the strike is over although no deal has been reached, does that qualify? (CNN, Politico, NYT, Kaiser Permanente, CKPU) On one hand, I think this literally satisfies the criteria described in the question and there is no guarantee that more strikes will follow. On the other hand, the strike at the outset was planned to only last three days, so perhaps the spirit of the question is more whether Kaiser-Permanente and the Coalition of Kaiser Permanente Unions.

@Nadja_L No weird spirit here, I created this question knowing only that the Kaiser workers were striking. I didn't know it was intended to be a short term strike and I suspect "no" traders didn't either. But things can happen, anyway, so even a short-intended strike can end up being long. This one ended, so market is resolved.

@MattLashofSullivan That's great! It just seemed to good to be true to me!

This is a good market, I didn't know about this! I'm going to add a 500 mana subsidy to encourage people to bet on it, and I'll probably add more if the strike lasts significantly longer than planned.