Kurt Cobain's top position has come about after his widow Courtney Love's sale of 25% of her stake in his work.
Peanuts cartoon creator Charles Schulz was in third place and earned $35m (£19m), followed by John Lennon - the former Beatle's work took $24m (£13m).
Forbes.com explained that for some dead celebrities, "their work, as well as their iconic images, continues to appeal to fans who remember them, and to those born long after they died".
The top 10 on the dead stars list was made up by scientist Albert Einstein, artist Andy Warhol, children's author Dr Seuss (Theodor Geisel), soul star Ray Charles, actress Marilyn Monroe and country singer Johnny Cash.
