>>116042874way back in the day (when Levitz was still around), they used to cut a lot of cheques to people for using plots, characters, or simply ideas.
They really didn't need to do it at that time because almost everything was work-for-hire, but Levitz did it anyways.
That's where stories like how Len Wein got more money for appearances of Lucius Fox than he did for all the Wolverine stuff combined came from.
I have no idea if WB/AT&T does that these days.