Is any sort of &quot;Public Domain Mark&quot; required when using public domain content? Say I wanted to use a painting from the public domain for a book cover. Is it necessary to apply any sort of &quot;public domain mark&quot;? If so, does it need to appear in a particular place (e.g., the cover itself vs. a copyright page)? The reason I'm attempting to do so is because commons.wikimedia.org has stated that one 'must also include a United States public domain tag to indicate why this work is in the public domain in the United States.'
If a work is in the public domain, then there are no particular requirements on its use; in particular, it can be used on a book cover without a copyright notice, a public domain notice, or any other kind of notice or mark. Wikimedia Commons' public domain template says, &quot;You must also include a United States public domain tag to indicate why this work is in the public domain in the United States.&quot; This is a notice to users of Wikimedia Commons, informing them that if they upload a public domain image to Wikimedia Commons, they must include a public domain tag. That's a policy of Wikimedia Commons. It doesn't apply to people using the image outside of Wikimedia.
It depends on where you are For example, in USA copyright exists in a literary or artistic work stored in permanent form like a book, a movie, an audio recording, a building etc. In contrast, in Australia there is no requirement for the work to be stored - that means copyright can exist in a spoken lecture. The owner of the copyright (usually, but not necessarily the creator) has the right to choose if and how their work is copied and if and how any derivative works may be made from it. For your example, the book is an original work in which copyright vests with the author(s), your notes are a derivative work in which copyright vests in you. However, you presumably did not have permission to make your derivative work so that makes it prima facie a copyright infringement. Fortunately, in the USA there exists a Fair Use defence and in Commonwealth countries the slightly less permissive Fair Dealing defence (if you are somewhere else you will need to do your own research). Search this site or read the copyright article on Wikipedia to learn about these defences. Long answer short (too late!), taking notes to aid your own study is almost certainly Fair Use/Dealing. So is sharing it with your friends. Publishing it may or may not be depending on all sorts of factors; for example, if you were to write a study guide for say a Harry Potter book for use by English literature students this is probably OK even if it is a for profit activity, because criticism is Fair Use/Dealing. Citing work is not necessary to comply with copyright law. Failing to cite may be academic misconduct but that is not a legal matter; its a matter for your academic institution.
Yes That is very simple - copyright is an exclusive right that starts automatically with the creation of a copyrightable work. The default situation is that the author has an exclusive rights to make copies of the work and derivative works. If the code is published somewhere by the author but the author has not said anything about its licence or copyrights, then the default situation applies - you need permission and you don't have it, so it's not legal for you to distribute their copyrighted works. They have the right to just publish it somewhere, others don't. If you try to contact the author and they don't say anything and ignore you, then the default situation applies - you need permission and you don't have it, so it's not legal for you to distribute their copyrighted works. If it's impossible to find the author (e.g. I have certain cases with literary works where it's not clear who inherited the rights after the author died), then the default situation applies - you need permission and you don't have it, so it's not legal for you to distribute their copyrighted works. That being said, certain forms of reuse (recreating ideas, learning from them, etc) would not be a copyright violation. But in general the situation with the author not saying anything is almost the same as the author explicitly stating "all rights reserved, you're not allowed to do anything, violators will be shot" - some specific uses are allowed even against author's wishes (e.g. 'fair use' clauses) but everything that needs their permission really does need their explicit permission.
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Everything except the summary and the cover art are all facts; facts are not subject to copyright. The summary and cover art would be subject to copyright. You may have a fair use defence given that all you are doing is cataloguing the books.
There aren't bright line rules in the area of fair use (which is the core issue - you are clearly copying a work that has copyright protected portions, at least - the question is whether fair use provides a defense and whether some portions are not copyright protected). This inquiry is fact specific and driven by general standards. Context such as whether the use would be free or commercial matter as well. For your own notes, anything goes pretty much. This generally wouldn't constitute "publication" of the work and would be for personal educational used by someone who paid for the book anyway. For shared notes - it depends. Also not all kinds of copying is created equal. Some parts of textbooks are themselves in the public domain or not protectable by copyright. For example, even a lengthy quote from a scientific journal article would probably be allowed with attribution. It would also be easier to evaluate based upon the type of textbook. A history textbook can have protection similar to trade non-fiction and can have very original exposition. An algebra textbook, less so. Your question also points to an end run. If the professor is the author of the textbook (many of mine were in something of a racket), you could get permission from the author.
The situation is complicated. The easy cases: In the United States, it's in the public domain for lack of a copyright notice. In countries that are parties to neither the Berne Convention nor the TRIPS Agreement, it's in the public domain because those countries don't recognize anyone else's copyrights. In countries that have adopted the rule of the shorter term, it is in the public domain because the image was never copyrighted in the country of origin. In the remaining countries, it is likely but not certain that the photo is in the public domain. Article 18 of the Berne Convention provides that: (1) This Convention shall apply to all works which, at the moment of its coming into force, have not yet fallen into the public domain in the country of origin through the expiry of the term of protection. (4) The preceding provisions shall also apply in the case of new accessions to the Union... So in theory, since it was in the public domain in the United States as of March 1, 1989 (the date the United States ratified the Berne Convention), it's in the public domain in all Berne countries. However, not all countries may have implemented Article 18 exactly as written.
It is reasonable to interpret the statement in their Github repository README.md as a "public domain" license for anything contained there. However, their "usage guidelines" backpedals a bit ("generally are not copyrighted", the misleading implication that content used commercially is subject to restrictions that educational and personal uses are not subject to). Although it is true that works "created by the US government" are not protected by copyright, not everything associated with a government agency is created by the US government. An agency might have a policy that they will not post material that is not copyright-free, there is no practical means of knowing if an item is an actual government work, versus a government-supported or government-hosted work (where copyright is held by someone else). If you trust their implication that all of those items in the repository are indeed government works, then they are free of copyright. I don't know any reason to not believe them, although sometimes the government is wrong and they end up liable big-time for infringement. However... NASA Open Source Agreement Version 1.3 (another copy on a NASA web page) on first glance seems to contradict the "government work" theory. Here, they claim to grant certain rights to users and also impose impose restrictions (including obligatory registration). This does not make any sense for a work that is in the public domain. The license is legally defective in that it fails to fill in relevant blanks (agency name, title of work, URL for obligatory registration). Also notice that the license is only for software. The scope of that license therefore has to be something narrower – it applies only to software, and presumably software that is not "a government work". I have no idea what software NASA could legally give away and is not a government work which is therefore not protected by copyright.