In the last 12 months, Cobain earned $50 million, which Forbes.com says is largely due to his widow, the always scandalous Courtney Love, who sold a 25% stake in his song catalog to publishing company Primary Wave.
That topped Elvis, who died in 1977 and reigned as the top earner from 2001-2005. Another musician, ex-Beatle John Lennon, was fourth.
In order to land on the list, the late celebrities needed to make at least $7 million since October 2005.
"Peanuts" creator Shultz and Dr. Seuss (Theodore Geisel) came in third and seventh, respectively, while country music great Johnny Cash — who released two new albums this past year — rounded out the top 10.
Forbes.com predicted that the future would be bright for late TV host Johnny Carson with the dawning of the YouTube era.
To see the full list of top earners, click here.