I'm not good at law, but I heard that in case of WW I photos copyrights are out of date (because more than 70 years passed). But I also heard another version that copyrights end after 70 years of photo author's death (in this case it would be trickier) and also that sometimes the copyrights can be passed to members of the family (is this true?). In case of some photos we see that they come from book author's collection. Does it mean that the author has any rights? In short - may WW I photos be freely used? If I want to write an article or a book do I need to worry about copyrights at all?
Just to reiterate what Tanker says, the laws are different from country to country.
And so the internet sort of makes a mockery of copyright laws; if, for example, I am working away in Elbonia and I am looking at photos on a site in Griknikistania, which country's laws should I be sticking to? Then, too, there is the problem of enforcing the law (once one has decided which country's laws apply).
There is a lot of information about copyright on wikipedia, because, presumably, they have run into this problem fairly often.
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