How does copyright over content that is not behind paywalled content work? I’m sorry but I like international law and consortiums exclusion right to ownership generally, so I would like that sort of answer to: How does copyright over online content that is not behind paywalled content work? Do people get some ability to share paywalled content?
Exactly the same way it works over all other content There are no special classes of copyright, there’s just copyright. What a user of a service may do with copyright materials will be spelled out in the licence. If there is no licence, then they are left with fair use/fair dealing.
(Since this is looking rather close to looking for legal advice: "I'm not a lawyer, this is not legal advice, don't sue my pants off".) The relevant section of the license is this (bolding mine): You may not exercise any of the rights granted to You in Section 3 above in any manner that is primarily intended for or directed toward commercial advantage or private monetary compensation. The exchange of the Work for other copyrighted works by means of digital file-sharing or otherwise shall not be considered to be intended for or directed toward commercial advantage or private monetary compensation, provided there is no payment of any monetary compensation in con-nection with the exchange of copyrighted works. Therefore, if you are using the content licensed under the BY-NC-SA primarily to make money, that is a breach of the license. Any more advice past that is wading seriously into legal advice.
The answer to this depends very much in which country you are in, and how you go about implementing it. First of all, this might seem obvious, but copyright only applies if you copy something that is covered under copyright. If you copy an idea - that having a library that solves problem X is useful - and that is the only aspect you copy, then under U.K. Copyright law, there is no copyright infringement, as ideas are not copyrighted. However, if you copy aspects of the library interface, or the object model of the original library, then it's a derived work, and the copyright of the new work is only partly yours. If you translate the source into a new language, then the copyright is largely still with the original author. Every country implements copyright law in their own way. One of the principle differences are in the available "fair use" clauses. You may find that you are entitled to a fair use clause for creating a "compatible" library, or you may be allowed to quote small aspects of the original in your new work. You need to check up on your countries laws.
You can licence your copyright under as many licences as you like to as many people as you like It's your copyright - you can do what you want with it. What you can't do is give someone an exclusive licence and then give licences to others - that would be a breach of contract with the exclusive licensee. How you let people know about the available licences is also up to you - your bio on Stack Exchange is fine.
You can read it, you can examine it to the point where you understand it, and then you can get inspired by the code and write your own code, without copying the code on the website, which does the same thing. If there is no license, then you can do what copyright law allows you to do. You are not allowed to copy the code, or create derived works by taking the code and modifying it.
The author of that work owns its copyright. Barring a licence that gives you the right to use it, you are infringing copyright. (I'm assuming no fair use in this case; i.e. the YouTube clip isn't actually about the audio track.) If you pay for licences, make sure the licence allows for the purpose you intend to use it for.
Your client is confused about how copyright law works (at least in the United States and virtually every other country I've ever heard about copyright in). If I were guessing, they read something like this from the United States Copyright Office: The copyright in a derivative work covers only the additions, changes, or other new material appearing for the first time in the work. Protection does not extend to any preexisting material, that is, previously published or previously registered works or works in the public domain or owned by a third party. and figured that because it's a derivative work, the copyright only covers the additions and changes they make, and there's no copyright protection for the original work. This misunderstands the law: the original work still has its own copyright (assuming it hasn't expired), and permission from the holder of the copyright on the original work is required to create that derivative work in the first place*. The copyright on the derivative work is separate—that is, both copyrights exist in parallel. * Some exceptions, such as fair use, exist, but would be unlikely to apply to the situation you describe.
You can design whatever this system is (leaving aside jurisdictions without First Amendment-like law that lets you design to your hearts content), the problem comes in implementing. The main legal question is whether you are operating a website. A website operator has to comply with various laws that require them to remove content. For example, if you operate a website that allows users to distribute content that they upload, they can distribute copyright-protected content, and you can be held liable for copyright infringement. DMCA in the US provides a way for you to not get sued, but you have to be able to remove putatively infringing content, so you could get sued if you can't remove illegal content. This may also include legal troubles over e.g. defamatory content where a plaintiff gets a court order to remove the content – you can't plead &quot;I can't it down&quot; if the court orders you to do so. Napster was sued for copyright infringement and racketeering for facilitating law-breaking by others (&quot;secondary infringement&quot;), and in MGM v. Grokster the Supreme Court annonced the general principle that One who distributes a device with the object of promoting its use to infringe copyright, as shown by clear expression or other affirmative steps taken to foster infringement, going beyond mere distribution with knowledge of third-party action, is liable for the resulting acts of infringement by third parties using the device, regardless of the device’s lawful uses Grokster's problems arose because they clearly intended the software to be used to violate copyright law, whereas it is unlikely that Github will get sued because it is possible to use the platform illegally. So it really matters exactly what this &quot;platform&quot; is and what your relationship to the platform is. Describing a system is generally not illegal, realizing and maintaining one can easily be.