Stand-up comedians take great pride in their jokes: often refining the jokes over months or years, constantly tweaking words and delivery to get the joke just perfect. When one comic allegedly steals a joke from another, it can be a big deal.
There are strong social norms regarding joke theft that are enforced in and by the stand-up community. But those norms do not necessarily line up with the legal boundaries of intellectual property protection over those jokes.
At their core, jokes have a premise and an execution. The premise is the underlying idea behind the joke. Louis CK has a famous joke (NSFW) about people being impatient when their smart phones are not immediately responsive, and how this contrasts to phones from as recently as twenty years ago.
The way I described Louis CK’s joke was by boiling it down to the premise – the idea underlying the joke. If you watch the video and compare my description and Louis’ performance, you’ll see how important the execution of the joke is. You can even find different videos of Louis delivering this joke over a couple of years, and you can see how he changes the execution slightly over time.
If, after seeing Louis perform this joke, I then performed a different joke with the same premise, I would likely be blackballed for having stolen a joke (depending on just how close those jokes are). This is where IP law differs from the social norms in the stand-up community.
Copyright law protects expressions of ideas, and not the ideas themselves. The premise of the joke that I outlined above is the idea undying the joke – and that idea cannot be copyrighted. The words that Louis CK uses to deliver that joke, however, are his unique expression of that idea, and that expression is copyrighted.
Don’t steal jokes.