How do I let others to share my research paper but without modifying its content? I'm about to publish a paper. It will be in PDF format. I want others to copy and share that file. But I don't want them to modify the content. What copyright license I should use for that?
The CC-ND license seems to be what you are looking for. However, Sec. 2(a) has two conditions, one allowing copying and distribution of the unmodified original (as stated in A), but also allows the user to modify but not distribute a modified version of the work (they may "produce and reproduce, but not Share, Adapted Material"). This would mean that a reader could rewrite your paper, as long as they keep it to themselves. If this bothers you, I think you could not rely on a standard named license, instead you'd have to provide your own – such as CC-ND 4.0 without clause (2)(a)(B). Rewriting a legal document is a risky proposition, even for a legal professional, because you have to carefully think through all of the implications of any new punctuation, adjectives, and deletions. If you contemplate deleting clause (2)(a)(B), you should come up with a line of reasoning that compels you do delete it in order to accomplish your goal, and check that the deletion doesn't thwart that goal. That is why people pay money to lawyers (and also why you need to make your goal clear to that lawyer, lest the agreement be inconsistent with your goal).
In the US, at least, facts - like the speed of light, the name of a dinosaur or the moons of Jupiter - are not copyrightable. But the words or pictures, designs and original work used to express and present those facts in books, websites and other publications by individuals and publishers are copyrightable. (Original work doesn't need to be published to be copyrighted; it is copyrighted at the moment of creation.) See How can &quot;factual&quot; intellectual property be protected? Plagiarism can be copyright infringement; it's copying and presenting work of someone else's as your own. But not all copyright infringement is plagiarism in the sense that someone is claiming others' work as their own: if you're selling a T-shirt with an unlicensed design, you're not really claiming the design is yours; you're just trying to make money. If you use all or part of an image or a quote or a song from a copyrighted source in your own work, you need permission and attribute the source. Or, you have to decide if the amount of the copyrighted material you are using might be Fair Use and you don't need permission. But decisions on what might constitute Fair Use are ultimately decided in court, because that's where can you end up when a person or a publisher sues you for alleged copyright infringement.
Generally, as the copyright holder, you can grant anyone a license to any or all of the copyright rights you have over your work (copying, distribution, derivative works, etc.). If you want to articulate unambiguously exactly what rights you are licensing, and optionally require attribution, you could use one of the Creative Commons licenses, which are designed for creative works. Some that would likely be a good fit for you are: Creative Commons Attribution license (CC BY) - Grants full rights to any recipient to use, modify, and distribute. Requires that all reuse mentions you somewhere in the work's credits. Creative Commons Attribution-ShareAlike license (CC BY-SA) - Grants the same full rights as the CC BY license except that any new derivative work made by a recipient must also be licensed under the CC BY-SA license. With the CC BY license, another person's modifications could be under a different license; under CC BY-SA, all modifications must be licensed under CC BY-SA when distributed, so the work and all its future transformations must be shared under the CC BY-SA license, forever (until your copyright expires, of course). This falls under the broad umbrella of copyleft licenses. CC0 - Functionally places your work in the public domain where it can be used by anyone with no restrictions (other than moral rights). CC0 allows you to renounce all claim to copyright on your work (to whatever extent possible in your jurisdiction), and/or freely license all the rights you hold in your work to the maximum extent possible (for jurisdictions where renouncing your copyright is not possible). There are also Creative Commons licenses that disallow commercial use and disallow the creation of derivative works, but you are probably not interested in those, since you want to grant full rights. One other factor to consider is whether you want to license the musical work itself or only the sound recording. By default, you might only be licensing the recording, which means other people cannot record a new cover of your music. (See Does a Creative Commons license allow me to record a cover of a song recording?) If you want to allow that, simply make a separate declaration when you license the work, saying something like, "In addition to the sound recording(s), I also license the underlying musical work under identical terms, to allow recipients to record their own covers based on this song."
It is not possible to say that this is generally fair use, although sometimes it would be. A copy for personal use is still a copyright right violation on its face, and fair use does not categorically exclude non-commercial or personal use of copyrighted works. It is a highly fact specific inquiry. The likelihood of anyone discovering that you have done so and deciding to sue over it is slight, but that doesn't mean that there isn't potential copyright infringement liability. Compare this to speeding. People do it all the time, and even driving one mile per hour above the speed limit is still a traffic violation. But it is rare for less serious violations to be ticketed.
Yes, a work with no license is All Rights Reserved, reserved meaning the creator of the work. Who is the creator of the work ? Everyone who contributed it, unanimously. Yes. If people contributed any copyrightable part of your work, in theory you cannot add any license or grant any right to use/reproduce/whatever the work without their unanimous agreement. That's very cumbersome, and almost nobody really does that, but it's what the law is. Big serious companies and repos require contributors to waive their rights on the code they contribute, by agreeing to a contributor's agreement. For example, python/cpython requires you to give your contribs a license allowing the python org to do essentially what they want with it, even though you retain copyright over them. If your project is not so serious, I suggest it should be enough to make the license clear, and that by contributing people are agreeing to place their contribution's code under the license. If it's a free license, that's all you need.
As the quote in your question notes (albeit in contrapositive form), Asimov's fiction may be made legally available for free download on the net with the permission of his estate. It is either that case that Princeton University's physics department (or whatever individual person or agency put up the story online) has obtained permission from Asimov's estate to distribute the story on their website, or they simply distribute it without legal permission, and Asimov's estate has not taken legal action to have it removed, which they may or may not choose to do in the future. Consider also that the Princeton distribution does not appear to have been meant to be in any way public: looking one directory level up (Princeton University Physics 115A and B: Physics for Future Leaders) shows a course overview with syllabus and lecture notes, without any apparent link to the story. Probably, it was put online for use exclusively by students taking that particular class, and the professor(s) just didn't put any controls to stop it from being accessible to anyone who knew the URL. This doesn't really change that fact that its public accessibility is, strictly speaking, copyright infringement, but it may be a favorable factor toward a finding that distribution outside of the class was innocent infringement, which can lessen (or, rarely, nullify) the penalty. (And it may be quite possible that distribution within the class was defensible under fair use/dealing, which considers educational context as a favorable factor.)
Generally speaking, if a person sends you an email you can publish it. Like if they call you a bunch of nasty names, or threaten you in some way, that information is yours and you can publish it. However, I'll give you three scenarios where you should not publish an email sent to you (and I'll edit to add more if they come up). Private facts. There is a tort called publication of private facts. A plaintiff must establish four elements to hold someone liable for publication of private facts: Public Disclosure: The disclosure of facts must be public. Another way of saying this is that the defendant must "give publicity" to the fact or facts in question. Private Fact: The fact or facts disclosed must be private, and not generally known. Offensive to a Reasonable Person: Publication of the private facts in question must be offensive to a reasonable person of ordinary sensibilities. Not Newsworthy: The facts disclosed must not be newsworthy. Stated differently, the facts disclosed must not be a matter of legitimate public concern. From Digital Media Law Project Note one thing - the offensive fact does not need to have been completely private for you to be liable, it must not have been generally known. In other words, someone like you who has a really low "public" bar needs to be careful. Also note that your buffer system might not help if the facts you publish are about someone other than the email sender; you are the one who published them. Stolen Information If someone sends you some intellectual property of a third party it is not yours to publish. Trade secrets, copyrighted works, prototype photos, etc. The sender might be breaking the law by sending the stuff to you but you're the one who published it so you can join as co-defendants. Barrett Brown was indicted for sharing a link to some stolen information. A link! He's in prison on other charges. Copyright held by the original sender (ht to @Dave_D) If the sender is the original author of the email, then the sender holds the copyright to the body of the email. Publishing the email violates the copyright. However, you could account for this in your buffer. Maybe. I am not sure is that is explicit enough.
(For the data you use, you might not have to follow the license. But let’s assume you have to.) The license only applies to the content you distribute (or publicly perform, but that’s likely not relevant in your context): "Distribute" means to make available to the public the original and copies of the Work or Adaptation, as appropriate, through sale or other transfer of ownership. It doesn’t matter what’s saved on your server, it only matters what’s published (i.e., distributed). So you don’t have to publish the database. You have to attribute the content from the database when and as long you show (i.e., distribute) it. Not earlier nor longer than that.