The copyright on Popeye has expired in the EU in jan. 2009, it expires in 2024 in the US: read more.There's also an article in dutch "Verbrand je vingers niet aan copyright ", where the author explains in a plain simple language what copyright (in dutch it is called author-right and differs slightly with the anglo-saxon copyright) is all about, and also gives the advise to beginining artists to use the Creative Commons license.