Not at all. If Zuckerberg had told the Winklevi he planned to quit and start a competing site, then there would have been no lawsuit. The harm was intentionall

Not at all. If Zuckerberg had told the Winklevi he planned to quit and start a competing site, then there would have been no lawsuit. The harm was intentionally misleading them, so they wouldn't find a replacement programmer to finish their own site. Your best bet is to be aboveboard, and get people to sign off on whatever they agree to, so they can't come back later with a changed story.