Question: I have a question about international copyright law. In my country, after a writer dies, it is 70 years before their works become public domain. It used to be 50 years, but that law was changed (non-retroactive). If a work is in public domain in one country, is it the same in all countries? And if the descendents of the copyright holder take care to maintain the copyright, with timely copyright renewals, does the work automatically become public domain when the time period is reached? What about companies that hold copyrights, do they lose their rights when this limit is reached?
Each country is different---which makes copyright law so...interesting. The longest copyright period worldwise (that I am aware of is) lifetime plus seventy-five years. So something that is public domain in one country may not be public domain in another country if they observe a longer copyright period.
That is actually complicated by works that were written before the current version of copyright law was enacted. The public domain mark is determined by what version of copyright law was in effect at the time that the work was created.
The public domain happens automatically once the limit is hit.
As an example, lets say that the country of Buymoira (*smile if you get the reference*) had a copyright law that said lifetime plus fifty before 1965, but changed it to lifetime in 1966 to lifetime plus seventy. So lets say that Ray Heinlein was a writer who wrote books both in 1965 and 1966---the works from 1965 would be life plus fifty, and the works from 1966 would be lifetime plus seventy.
Where it gets complicated when researching public domain status is that some countries used to have a copyright period that was X number of years from date of reregistration, with an additional Y number of years if (and only if) the copyright was renewed. And you had to file in each separate country.
An example of a work being public domain in a country while still being under copyright in another country was Dracula. It was properly registered in England, therefore no one could use the work without a license. But it was never copyrighted in the United States which resulted in lots of films being made using the character and without the widow of Bram getting a single dime.
There are a score of pulp fiction stories written in the United States during the register and renewal period that may or may not be under copyright depending upon if the copyright was renewed or not. (Often if a work had quit selling well, it was not renewed.) Basically, for works written in that time period, you have to trace down the status of each work individually.
(An interesting side-effect of the rule that copyrights had to be registered in each individual country is that all the big name publishers in the United States were located on the East Coast. The publishers would literally grab newly published books from Europe and rush them into print in the United States before the authors could register them in the USA. This is why there are some copies of The Hobbit with an note thanking readers for buying the official edition---Tolkien only received income from the official edition, and none from the "pirated" edition.)
An additional complication is that some works were "written for hire"---aka the writer was paid a check for writing the work, and someone else (typically a company) owns the copyright. The copyright period for such works are typically "date of completion plus Z years." This means that you are not interested in the date of the author's death (often you have no clue who wrote the piece--they could be faceless advertising copywriters), but rather than the date of completion of the work in question. The longest period that I know of for work-of-hire copyright is date of completion plus one hundred years.
of the most important changes in modern copyright law typically (not
true in all countries) is automatic copyright (no registration needed to
have copyright protection), and recognition of copyrights from other
countries (no need to separately file
for copyright in every country in the world). These two changes
happened before the internet, but are proving to be very important in
the modern internet age.
is still one reason to consider official registration. For instance,
in the United States, official registration allows you to sue for
monetary damages if someone copies your work. Furthermore, if you write
fiction, a movie company will only option your work if you are