Requirement of attribution when reusing Wikipedia articles licensed under CC BY-SA All of Wikipedia's content is licensed under the CC BY-SA, and Wikipedia encourages fulfilling the attribution requirement for CC BY-SA by linking to the original Wikipedia article, which contains a page history with all authors attributed. However, Wikipedia deletes articles on occasion, causing page history to become inaccessible. If I am a (partial) author of a Wikipedia article that was reused under the CC BY-SA by someone else, but then Wikipedia deleted that article (and with it, the attribution), do I have the right to send DMCA takedowns to websites that attributed that work simply by linking to the original (now deleted) article?
No. The Creative Commons license seeks to promote recognition of the original author's work through attribution, but does not provide the same framework for enforcement that the DMCA would. The proper approach in cases such as the deleted Wikipedia article and subsequent reuse would be to provide a courteous notice to Wikipedia of your original publication and ask to be listed as the original author or be provided attribution. In the absence of relief there, then what rights you have would be determined by the Wikipedia Terms of Service. Since, and I am assuming here, that you are not generating billions of dollars on the original publication in royalties, seeking to bring a DMCA type enforcement on a Wikipedia article dispute would be like trying to swat a fly with a sledgehammer. (or more commonly in divorce, two people having hearing and spending thousands of dollars on attorney's fees fighting over a blender -- they are free to do it, but they would have been much better off buying 500 new blenders...) Keeping perspective and providing a courteous letter is probably your most cost efficient first step in situations like this. And in all areas of law, just remember, you catch more flies with honey than you do with salt. (meaning taking the courteous approach usually affords better results than a scalding letter breathing hell-fire and brimstone) In followup to earlier comment: Presuming you would be covered by the World Intellectual Property Organization Treaty on Copyright of 1996 (as a U.S. Citizen you would be), and your copyright is on file with the United States Copyright Offices (same presumption) as prerequisite to suit, then there is nothing that prevents you from invoking the protections under general copyright law and under the DMCA (inlcuding the Takedown provisions). Note: these are not the only prerequisites to taking action, but instead the minimum critera to qualify, and note this does not pass on the wisdom of doing so (there are often significant consequences to improperly invoking previsions of certain acts).
Yes, that’s allowed. Under the Stack Exchange terms of service, content you upload is licensed to Stack Exchange Inc. on a non-exclusive basis under CC-BY-SA 4.0. The terms of service do not give Stack Exchange the copyright to your contributions, and a non-exclusive license means you are not promising Stack Exchange that “only Stack Exchange will be allowed to use this content.” That means you can continue to do whatever you want with your own content and do not need to mention Stack Exchange at all. The only restriction is that you can’t stop Stack Exchange from continuing to use your Stack Exchange content under CC-BY-SA 4.0, and since it’s a Creative Commons license you also can’t stop anyone else from using your Stack Exchange content under that license.
Is an article licensed under an Open Access license equivalent to a public domain work? No. Intellectual property practitioners and professors often describe copyright as "a bundle of sticks." This means that intellectual property laws grant the creator of a copyrightable work a large number of rights, and the creator can grant or deny others each of those rights individually. So, for instance, an author can grant a publisher the right to publish his or her book in one country, but not in another, or to copy it verbatim but not to alter it. The purpose of a license, any license, is to specify which of those rights pass to the licensee (the end user) and which stay with the licensor (the creator). This is true of creative commons just as it is for any other license. For example, many open access publishers publish under the Creative Commons CC-BY journal. This is an attribution license; it requires as a term of the license that you give credit to the original creator. This is something you would not have to do with a public domain work. In addition, under CC-BY, you have to include a copy of the license with each copy you distribute, and you cannot add your own copy protection to any copies you distribute. Again, these sort of restrictions do not apply to a public domain work. In short: the purpose of a license--any license--is to define the ways in which you can, or can not, use the licensed materials. Any license that contains any provisions restricting the licensee's use is going to be more restrictive, by definition, than the use of something in the public domain.
One big hole in any scheme that relies on copyright is that it could not preclude people talking about the previous content or talking about you. This is well established First Amendment law. For example, see Near v. Minnesota 283 U.S. 697 (1931), which holds that except in rare judicially established exceptions (relating to military information, obscenity, and inciting acts of violence), government censorship is unconstitutional. Thus, no statutory scheme could be used to prevent third parties who happened to have seen the material while it was freely available from re-iterating what they had seen, or talking about it, or talking about the author (you). People could even reproduce portions of the published content. Some types of reproduction would be protected as fair use in the US, especially if the reproduction is for the purpose of criticism. (17 USC 107, and this previous Law.SE answer) The closest approach would be to protect your work as trade secret, making sure that anyone that you share it with agrees to non-disclosure. But, if you "publish unique content under this pseudonym" there is no way to "arbitrarily or wholly revoke discussion about that content". If the cat gets out of the bag, while you may have remedies against the person who violated the non-disclosure agreement, you would not be able to prevent third-party discussion or reproduction.
If your app is published under US law, then the DMCA would apply, just as if it was a web site. The DMCA doesn't say anything about what particular technology the distributor is using. TO be protected by by the DMCA's &quot;safe harbor&quot; provision, you will need to include a notice in your app that you accept takedowns, and provide an address or method by which they can be sent, and an agent who will receive them. (You can be your own agent if you choose.) When and if you recieve a take down notice, you must check if it is valid in form. According to this Wikipedia article, a takedown notice must include: (i) A physical or electronic signature of a person authorized to act on behalf of the owner of an exclusive right that is allegedly infringed. (ii) Identification of the copyrighted work claimed to have been infringed, or, if multiple copyrighted works at a single online site are covered by a single notification, a representative list of such works at that site. (iii) Identification of the material that is claimed to be infringing or to be the subject of infringing activity and that is to be removed or access to which is to be disabled, and information reasonably sufficient to permit the service provider to locate the material. (iv) Information reasonably sufficient to permit the service provider to contact the complaining party, such as an address, telephone number, and, if available, an electronic mail address at which the complaining party may be contacted. (v) A statement that the complaining party has a good faith belief that use of the material in the manner complained of is not authorized by the copyright owner, its agent, or the law. (vi) A statement that the information in the notification is accurate, and under penalty of perjury, that the complaining party is authorized to act on behalf of the owner of an exclusive right that is allegedly infringed. (See the actual text of the relevant section of the law.) If you receive (through your designated agent) a valid takedown notice, you must promptly remove the content and notify the poster (or you can instruct to poster to remove it, but you must do so yourself if the poster does not). If the poster then files a valid counter notice (see the linked sources above) with your agent, you must notify the sender of the original notice, and if the sender does not notify you of a copyright suit filed within 10-14 days, you must restore the content. Provided that these rules are complied with, the host gets a 'safe harbor&quot; and cannot be sued for copyright infringement, nor for the act of taking down the content. I believe that the agent must be registered with the US copyright office. The courts have not ruled on just how quickly an ISP or other host must react to the takedown notice. It must be &quot;expeditious&quot;. Moreover, Under the DMCA (i) 1) (a) The host must have, post, and enforce a policy denying access to repeat infringers, or lose safe harbor protection. The text of the provision is: (i) Conditions for Eligibility. -(1)Accommodation of technology. —The limitations on liability established by this section shall apply to a service provider only if the service provider— --(A) has adopted and reasonably implemented, and informs subscribers and account holders of the service provider’s system or network of, a policy that provides for the termination in appropriate circumstances of subscribers and account holders of the service provider’s system or network who are repeat infringers;
In general, using content provided by another who incorrectly posted it under a permissive license, such as a CC license, does not grant a valid license from the real copyright holder. That is, if A writes some code (or a song, or creates an image, or whatever else), it is protected by copyright. If B then posts it to the web, with a statement that it is released under a particular license, without having obtained permission from A, then B's &quot;release&quot; is of no value, because B had no rights to grant. If C downloads and uses this content, relying on B's license, then A could take legal action against C. C would probably be considered (in the US) an &quot;innocent infringer&quot; which reduces the minimum statutory damage amount, but does not otherwise change C's legal position. A could, if it chose, bring suit and possibly obtain a judgement including some damages. But to return to the practical case of code posted on one of the SE sites. Given the comparatively short code sections usually posted, and that they do not usually form a complete working program, and given further the stated educational purpose of SE, it is likely that in US law such a posting would constitute fair use, and in the law of other countries fall under one or another exception to copyright. That is a general conclusion, the details would matter. I have not heard of a case similar to that suggested in the question. I find it unlikely that an SE poster would post copyright-protected code without permission, that is valuable enough to be worth an infringement suit, and substantial enough and having enough effect on th market for the original to be outside the protection of fair use. Such a situatiion is, of course, possible, even if unlikely. Note that a cease-and-desist letter is not a court order, and is really only a threat of court action. its only legal effect is to put the recipient on notice, so that continued infringement is not without awareness of the copyright claim. To have legal effect the claimant must actually bring an infringement suit, which is not without cost.
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.
Online file converters are legal: there is no law that prohibits a person from making a program available and executing online, including creating output in the form of a file. It is possible that some person may illegally copy copyright-protected material then use a website to modify that material, in which case the question of vicarious liability for copyright infringement could arise, so we appeal to the DMCA safe harbor provisions to see what the website must do. First, the owner of copyright must submit a properly constructed takedown notice to the website. Crucially, the notice must contain sufficient information that the website operator can find and take down the item(s) in question. Assuming that the complainant can supply the &quot;where is it&quot; information, then there is a notice and counter-notice routine where the uploader is informed and can deny the accusation – the website operator doesn't evaluate the merits of the claim, he only sees that the formalities were observed. If the operator follows the rules, he cannot be held vicariously liable. If the link does not expire and if it is somehow promulgated, the technical potential for being a contributor to copyright infringement becomes very real, but it puts the operator in no worse a legal position than Youtube. So the question is not just related to OCILLA, it is entirely covered by that law. Questions of how users or website owners are &quot;supposed to&quot; act don't figure into this. If the website owner does not comply with those provisions, they have no access to the safe harbor provisions, and they can be sued. However, the website itself remains legally &quot;permitted&quot; (there never was a prohibition of such a website).