Can code logic be copyrighted? Scenario: I work at company A and write some code for them which is something trivial but used in a product that is proprietary and hence the code is company property. Then I leave the company A and join company B. Company B needs something that can use the code and logic I learned in company A. There is very little I can change in code I learned at company A to get the similar functionality. Question: Am I infringing on the copyrights of company A because the code is similar? Is it possible to copyright ideas and logic such that if you designed something in company A you may never design it, even from scratch, in company B? Are there any workarounds? Otherwise you'd run out of your skills due to all your work being copyrighted somewhere or other.
Algorithms can be patented, e.g., https://en.wikipedia.org/wiki/RSA_(cryptosystem)#Patent (and see, e.g., https://en.wikipedia.org/wiki/Software_patent for further discussion). Copyright is only for specific code. So if your Company A has copyrighted the code you wrote, but not patented the algorithms implemented by that code, then you can subsequently go to Company B and legally reprogram those same algorithms.
Whenever there is a license to share things, the license creator wants the license to be widely used, but absolutely does not want slightly different licenses that could be used to trick people, or that just cause legal problems when used. Normal copyright law applies. And for the reasons above, the GPL license as an example allows you to copy the license verbatim but absolutely doesn’t allow you to make any modifications other than changing who is the person licensing a work. I would be curious what happens legally if someone licenses something with a sneakily modified copy of the GPL and then makes claims against a licensee who assumed it was the original GPL.
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.
All your work is yours. They've made it very clear it wasn't a work for hire, so it's yours. They can't copyright any of their ideas. You can't copyright an idea. Only specific creative elements authored by them and present in your work could be covered by copyright. You didn't use their block diagrams. I don't see how references to other sites to look at would constitute a creative element they authored. That said, you probably want to talk to a lawyer and get a written legal opinion that you can rely on.
The basic principle about copyright protection is that the expression of an idea is protected, but the idea itself is not. So wholesale copying without permission is infringing. But the abstract algorithm is not protected by copyright (and let us assume that it also isn't patented). By way of analog, an insertion sort is a pretty easy concept to grasp, and once you understand it, you can re-create it, independent of how the original example (where from you learned about the sort) is expressed. So the question is whether it is necessary for you to copy that code (copyright protects against copying), or can you independently re-express the algorithmic idea (ideas are not protected)?
The designer/company owns the copyright to the original work, you own the copyright in the derivative work (the screenshot). However, your work is subject to whatever rights your license to use the game gives you and fair use/fair dealing. An example of a company attempting to enforce copyright from screenshots/screen recordings can be seen by the Nintendo Creators Program.
First of all being the &quot;founder&quot; of a startup in no way implies that one wrote all the code of the startup's primary or signature app. The founder could have hires coders, or had partners, or used open source code. But let's make some assumptions. Suppose Alice has created a startup, and wrote the code for an application. Suppose Bob invested in the startup, and got 30% of the stock, What rights does Bob have to the copyright on the code? It depends entirely on what agreements Alice has made. Alice might have sold or assigned the copyright to her startup firm, call that F1, If so, F1 owns the copyright, and Alice can't reuse it without F1's permission. If Alice has retained the other 70% of F1, she controls it and can have it grant her whatever permissions she likes. But if she has sold or assigned a majority shore to investors, she will need to persuade the management of F1, or a majority of the shareholders, to grant her permission. Alice might have merely licensed the code to F1. In this case she retains the copyright. If the license was not exclusive, she can use the code as she pleases, but so can F1, in accord with the license. In neither case does Bob directly own the copyright, or a share in it, unless a separate agreement granted or sold that to him. But he has a right to a share of the profits, if any that F1 makes, and a right to vote on decisions that 1 makes, long with other owners of F1 If Alice never formally transferred or licensed the software to F1, she still owns the copyright and can do as she pleases, even if shew sold most or al of F1 Note that to transfer a copyright there must (under US law) be a written and signed document, one signed by the owner or the owner's agent. It must specifically indicate what copyright(S) it transfers. A purchase of an interest in a business does not suffice without such a document.
You have a false premise: "it offers the same conditions", and "MIT license is functionally equivalent to CC-BY". These premises are not true. CC-BY: applies to more than just software; it applies to artistic or literary work, databases, other material disclaims endorsement explicitly withholds moral rights explicitly does not license patent rights (MIT license gives anyone who obtains a copy of the software the right to use it, a patent right) prescribes the acceptable forms of attribution Those are just some of the differences.