21

The Free Software Foundation invented the term Copyleft. Here's what they have to say about it: Copyleft is a general method for making a program or other work free, and requiring all modified and extended versions of the program to be free as well. The simplest way to make a program free software is to put it in the public domain, uncopyrighted. ...


17

If you are looking for something very permissive then you do have to use a license. Quoting GitHub's help page about licensing: Generally speaking, the absence of a license means that the default copyright laws apply. This means that you retain all rights to your source code and that nobody else may reproduce, distribute, or create derivative works from ...


12

http://choosealicense.com/licenses/ also has a listing of licenses as well as comprehensive listings of what they are capable of. For your purposes, WTFPL and The Unlicense provides an ultimately high freedom for your code to be reused.


10

They are also planning to change the licensing of the project, or make it dual-license. Unless you have signed a CLA or assigned the copyright of your contributions in some way, they cannot legally do either of these options. You are the copyright holder of your contributions, and therefore you, and only you, get to say which license or licenses they are ...


10

Short answer: Copyleft is a term coined by the FSF and implies that if you distribute a derivative work of a work under a copyleft license, you must distribute the derivative under the same license as the original work (it may however be combined with works under a permissive license that is deemed "compatible", read on). Some people use the pejorative name ...


9

You cannot license the work as a whole under CC0. You do not have the ability to commit other authors' work to the public domain or remove an author's requirement that distribution of their work includes attribution. You can release your own code under CC0, and include that code in a derivative work that also includes MIT/BSD-licensed code from other ...


8

That's pretty basic: an open source license is irrevocable. Code that was released once under the terms of an open source license can always be used under these terms if someone mirrored it so it is still available. If you change your mind it means that you cannot retract your earlier decision. You only can enforce a new license on new contributions, but if ...


8

If you create your software and you release it under a permissive license first, you can offer that product under a commercial licence later, but you will have a hard time making money because the "free version" will compete with the "paying" version. I have done this before. I started with a product under the LGPL. This is better than the Apache Software ...


7

Copyleft emphasises that you can not do everything with the source. The usual example is GPL-style restrictions, which do not allow using the code in a closed-source project except as SAAS. (The “left” is sometimes interpreted as: you have to give your own code back if you want to have the benefits of somebody else's open-source project.) Permissive ...


7

In brief, item #1 is incorrect, and item #2 is broadly correct, with possible exceptions. You may release a copyrighted work under any number of licenses independently and simultaneously. The fact that you offer some of your code under a CC BY-SA in no way impedes your ability to also offer it under the Apache 2 license, and vice versa. You are the ...


6

The other explanations are accurate but here is a simpler version: Permissive A permissive license typically lets anyone do anything with the code but cannot sue the author if there are bugs. Some also require anyone who distributes the code to mention where they got it from. Copyleft A copyleft license forces any "derivative" work to also be open ...


6

There are several reasons to use a permissive license: You want to maximize use of your software, and are perfectly happy to see your software made into proprietary software. In authoring the GNU GPL, Stallman wanted to make matters more advantageous for free software and more disadvantageous for proprietary software. That was his goal -- and he achieved it ...


5

I recently worked with the team at GitHub to provide more information about 0BSD. More info about Landly's 0BSD now appears on choosealicense.com and, subsequently, will appear on GitHub license drop-downs (takes time). Beyond that you can also find more info about 0BSD on Wiki which I added after you asked this question. Other places to seek information ...


3

You certainly can fork the project and perhaps get developers move over to your fork. I'm sure many of them feel like you do. This has happened before: Libre Office from Open Office, Maria DB from MySQL, ...


3

There is at least one reason to avoid 0BSD: it's not popular. Meaning that most likely it was not reviewed by most corporation's law departments. If I were to use or contribute to 0BSD code at work I'll have to chase Google lawyers to clear it. Apache 2 is generally recommended as trouble-free.


3

I would go with the MIT or BSD 2-Clause licence, because they're for one thing well known (as stated by Carpetsmoker), and because they can't hold you liable when something goes wrong and because (as well stated by Carpetsmoker) is some people might get all funky about the Do What The F*ck You Want licence. You're not restricted to a license that's already ...


3

There's an excellent site that explains license types in plain English. https://tldrlegal.com/. The TL;DR version to that, that if you want a permissive license, go with either MIT or Apache License, the main difference being that Apache License requires modifiers to keep a disclaimer and copyright line untouched.


2

"I am not a lawyer" but this is generally a good idea. Apache is actually very good for this. From experience (including legal discussions) such as license allows you to push out an open source version, and then develop a much more capable closed version based on the same code. Using an appropriate CLA also ensures that all community contributions can be ...


2

Both permissive and copyleft licences can work great, but they give rise to slightly different scenarios. Let's assume you have written an open source project OS, and a commercial fork COM. In the permissive scenario, others are allowed to do more with your work, and you are allowed to do more with your contributors work. In this scenario others can take ...


1

0BSD is awesome. It seems fully legit for opensource in my recent research. Previously I was using ISC but I prefer 0BSD because I dislike copyright statements. I put 0BSD in this opensource template and plan to change all my opensource projects to 0BSD. I hope 0BSD gets hella popular.


1

The original License for library/framework and the demos is APL 2.0, but I would like to use MIT/X11. Since this is a port and as you mentioned this means class, func and even variable names are almost identical ... then I doubt you can relicense this under another license unless the original license explicitly allows such thing. Assuming that your APL 2.0 ...


1

Yes you can. No you don't need permissions. The license text is pretty clear to this effect.


1

Permit me to first go for kicking in the open door. The ability to fork can override the copyright owner's desires if and only if it's not the owners desire that the project is forked. Permissive licenses were specifically invented for this. It is possible that not every larger project will play out as this scenario, but it is certainly the intention of ...


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