That's it. Though the law (US, EU) has been changed recently to extend copyright protection for an even longer time past the authors lifetime. Some year ago it

That's it. Though the law (US, EU) has been changed recently to extend copyright protection for an even longer time past the authors lifetime. Some year ago it was afaik 70 years after the author died. The Encyclopedia Britannica from 1911 is now public domain but songs from Elvis Presley were owned by Michael Jackson (his daughter was together with him for some time) and will make another generation or two of his childrens rich (or whoever owns the rights now/then).