Na literatura são 75 anos até ser domínio público.

Mas na literatura não se pagam direitos para citar (o que seria feito das recensões literárias?). Pagam-se é direitos para publicar.

Essa é uma questão pertinente. No caso das obras literárias até quando dura o direito de autor? E depois é do dominio público? E com as músicas a mesma coisa?

Se assim é, porque razão tenho que pagar para utilizar uma citação de Platão, p. ex.?

E aí entramos na discussão teórica do papel da função de autor, e em que medida é que isso se esgota. Mas penso que esse não é o caminho.

Duration
Copyright subsists for a variety of lengths in different jurisdictions. The length of the term can depend on several factors, including the type of work (e.g. musical composition, novel), whether the work has been published or not, and whether the work was created by an individual or a corporation. In most of the world, the default length of copyright is the life of the author plus either 50 or 70 years. In the United States, the term for most existing works is a fixed number of years after the date of creation or publication. Under most countries' laws, copyrights expire at the end of the calendar year in question.

The length and requirements for copyright duration are subject to change by legislation, and since the early 20th century there have been a number of adjustments made in various countries, which can make determining the duration of a given copyright somewhat difficult. For example, the United States used to require copyrights to be renewed after 28 years to stay in force, and formerly required a copyright notice upon first publication to gain coverage. In Italy and France, there were post-wartime extensions that could increase the term by approximately 6 years in Italy and up to about 14 in France. Many countries have extended the length of their copyright terms (sometimes retroactively). International treaties establish minimum terms for copyrights, but individual countries may enforce longer terms than those.

In the United States, all books and other works published before 1923 have expired copyrights and are in the public domain. In addition, works published before 1964 that did not have their copyrights renewed 28 years after first publication year also are in the public domain, except that books originally published outside the US by non-Americans are exempt from this requirement, if they are still under copyright in their home country (see How Can I Tell Whether a Copyright Was Renewed for more details).

But if the intended exploitation of the work includes publication (or distribution of derivative work, such as a film based on a book protected by copyright) outside the U.S., the terms of copyright around the world must be considered. If the author has been dead more than 70 years, the work is in the public domain in most, but not all, countries. Some works are covered by copyright in Spain for 80 years after the author's death.

In 1998 the length of a copyright in the United States was increased by 20 years under the The Copyright Term Extension Act. This legislation was strongly promoted by corporations that had valuable copyrights that otherwise would have expired, and has been the subject of substantial criticism on this point.

E também: http://www.wipo.int/about-ip/en/ (nomeadamente http://www.wipo.int/freepublications/en/intproperty/909/wipo_pub_909.pdf)
Encontrei mais informação em http://www.pdinfo.com/index.php (e http://www.pdinfo.com/copyrt.php).

Works published in the United States with a copyright date of 1922 or earlier are in the public domain in the United States.
Copyright protection outside the USA is determined by the laws of the country where you wish to use a work.  Copyright protection may be 95 years from publication date, 50 to 70 years after the death of the last surviving author, or other criteria depending on where the work was first published and how the work is to be used.

Os concertos não dão lucro? Então porque raio existem cada vez mais grandes promotoras de concertos em Portugal (a última da cisão na Música no Coração), e porque raio Portugal continua a ser de longe o país europeu com maior média de concertos por pessoa? Não dá lucro? Então essas promotoras não vão à falência? 

Carol, acho que normalmente só se é acusado e condenado (como diz o Green Lion, o juiz absolviria noutras situações) se se ganhar dinheiro com a pirataria. Ou seja, se fizeres cópias e as venderes.

queria dizer indiciado. peço desculpa

E porque raio tem de existir editoras??pelo menos na forma e trabalho que conhecemos..
O mundo ta em constante evolucao, e ha profissoes que vao desaparecendo, para dar lugar a outras...
Nao me lembro de terem feito tanto drama quando alfaiates, e outras inumeras profissoes deixaram de existir para dar lugar a producao em massa..
Se as editoras querem ter lucro, têm de arranjar maneira de se adaptar, agora andarem a fazer choradinho e a dificultar a vida de milhoes de pessoas para lucro de umas quantas empresas..poupem me!

Hum...deixa-me pensar....talvez porque fazer empresas que dão lucros e recompensam os accionistas que investiram nelas é a filosofia económica vigente no occidente há mais de 100 anos com o nome de capitalismo e há mais de 1000 anos com outros nomes, é a base da nossa forma de vida e pensamento cultural e económico? Talvez por isso?