&quot;GPL version N or later&quot;-licensed code and publishing an EULA as GPL v4 Oftentimes source code is licensed as "GPL version N or later". But what stops some company from taking their EULA, publishing it as GPL version 4 and happily using whatever code they want to use in a way they want to use?
The Gnu General Public License text specifically refers to versions published by the Free Software Foundation when availing yourself of the “or any later version” option: If the Program specifies that a certain numbered version of the GNU General Public License “or any later version” applies to it, you have the option of following the terms and conditions either of that numbered version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of the GNU General Public License, you may choose any version ever published by the Free Software Foundation. Gnu GPL version 2 Gnu GPL version 3 Therefore, only the Free Software Foundation can do as you describe.
There isn't a meaningful difference; they just renamed it for version 2.0. Comparing CC-BY-ND-NC 1.0 and CC-BY-NC-ND 2.0 side-by-side, one can easily see that their scope is the same--there is some rewording, but that rewording is common to all CC-1.0 vs. CC-2.0 licenses, and not indicative of any change in the fundamental scope or purpose of CC-BY-ND-NC vs. CC-BY-NC-ND.
There is no contract between you (the licensee) and the licensor of the software. The creator of the open source software just says "here's the software, you may use it if you like, as long as you fulfil some conditions. ". No contract, no liability. I think the developer would only be liable if they intentionally created software that causes damage. (Which has happened, some open source browser plugins have recently been modified to run bitcoin mining software, or worse. I suppose the miscreants could follow all the GPL rules or whatever license is used).
Assumptions Let us assume that the code involved was created during the period of employment, was within the scope of that employment, and was validly work-made-for-hire (WFH). In that case, the code copyright is owned by the former employer.dn the person who wrote it has no more rights than a random stranger would. I am also going to assume US law. Ownership of Ideas Who owns the ideas, the knowledge of how these libraries work? No one does. In the absence of a patent, no one ever &quot;owns&quot; an idea. ]17 USC 102(b)](https://copyright.gov/title17/92chap1.html#102) provides: (b) In no case does copyright protection for an original work of authorship extend to any idea, procedure, process, system, method of operation, concept, principle, or discovery, regardless of the form in which it is described, explained, illustrated, or embodied in such work. Derivative Works Copyright law does prohibit anyone making a derivative work from a work protected by copyright without the permission of the owner. A derivative work is one &quot;based on&quot; the source work. The classic case is a translation. Exactly when a piece of software is a derivative work of another is fact-dependent. Bu several things are clear. If the source work is trivial and obvious, ther may not be sufficient &quot;originality&quot; for the source work to be protected by copyright at all. If the source work is not protected by a valid copyright, nothing is a derivative work of it. A &quot;hello world&quot; program, for example, is probably not original enough for any copyright. A straight-forward implementation of a basic algorithm like quicksort is probably not original enough, either. If there is only one way, or only a small number of ways, to express the ideas of the source work, the merger doctrine applies. This means that the expression of the work is merged into the idea, leaving the expression unprotected. When the merger doctrine applies, there is, in effect, no copyright. If a work copies ideas from a source, but none of its particular expression of those ideas, the result is not a derivative work, and is not an infringement of copyright. If a work is definitive, but is also a fair use of the source work, it is not an infringement. The usual four-factor fir use analysis must be made to determine this. In particular, if a work is highly transformative, it is likey to be found to be a fair use. Issues from the Question What if the new code (presumably, in the case of something simple) comes out exactly the same (even if I rewrite it without looking)? That Rather suggests that the work was too trivial to be original enough to have copyright protection at all, or else that there are only a few ways to express the idea, and the merger doctrine applies. But if neither o those were true, this might be an infringement. [* To be coninued*]
What you are missing is that the original copyright holder can give permission to make derivative works with strings attached. There is no automatic right to derive something from a copyrighted work. Those strings could include constraints on what you create in the process of making the derivative work. Yes it is a string limiting what you can do with something you own, but you would have been warned in the license and had the choice to start from scratch. People do create work-alike software with no copyright strings using two teams and a &quot;clean room&quot; design process. It is a lot harder than modifying something another person has developed. Also, law and someone's understanding of morals need not be aligned at all. And, in patent law, just creating something all by yourself from scratch does not give you ownership. If someone else did it first and got a patent you can't make the item you might think you own. IP law is complex and looking for &quot;fundamentals&quot; may not get you anywhere.
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.
It seems that you don’t understand what parody is. If you do understand, please explain how it’s even possible to parody computer code. What you can do with “open source” code depends on the licence the copyright holder(s) release it under. For some very permissive licences you can do what you suggest, for most, you can’t.
Both. The user made an infringing copy with the upload, the developer did with the download. Further the ToS between the app owner and the user will not protect them from being sued by the owner of the copyright. They don't have any ToS with them.