„There are a large number of ways that books might fall into orphan status. A quick consultation of Peter Hirtle’s copyright table at Cornell Univ. allows us to see how easy this is. The impact of foreign rights is fiendishly complicated, and even the rules for U.S. publications are baroque; for older works it is a crafty rightsholder indeed who can figure out whether they might retain a claim. As Peter Hirtle observed to me in an email, ‚The lengthening copyright terms and the gradual removal of formalities (especially the automatic renewal of works published since 1963) means that works that would have passed into the public domain in the past because the rights owners weren’t concerned are still protected. The chances that the rights holders are either unidentifiable or not locatable also goes up.‘
There are rough estimates of around 7 million digitized volumes in GBS [Google Book Search] subtracting 750,000 newly identified works gives us 6.25 million. Let’s take a guess that there are maybe 1.5 million public domain works (this is not entirely out of the blue, but informed by earlier orphan works studies and reports), leaving 4.75 million titles. That’s a lot of books – about 2/3 of the total. It might be more, it might be less; it is a big number.
A large number of these orphans are going to be truly public domain books, just like pre-1923 works. However, we may never know that they actually have public domain status due to historically incomplete record keeping, and the lack of a national rights tracking and notification infrastructure.“ (via Archivalia@Twitter)
Article „Public domain“ on Wikipedia
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