BillyBatson4360 wrote:
If I understand you correctly, then why aren't the New Gods a property of the Kirby estate? They seem pretty clearly a property of DC Comics as DC has published them and used characters from them in a myriad of other projects and properties. As far as I have ever known or read, the Kirby estate is not receiving royalty payments for those characters.
As alexarkadin pointed out, DC does own the Fourth World.  However, in 1982, they still offered Kirby creator credit and royalties for use of the characters in the Super Powers cartoon and toys even though they were under no obligation to do so.