Add license information

[quassy]

I think the elementary+ icon set should get a proper license with copyleft (maybe CC-BY-SA or GPL).

[Manuel-Kehl]

That is true. Let's elaborate the possible options:

1. GPL for Everything

• SVGs are technically markup code and thus can be GPL licensed
• Keeping everything under the same licence avoids compatibility problems within the collection itself

2. GPL for the code, CC-BY-SA for all sorts of arts

• CC may appear more appropriate for icons, from a "semantic point of view"
• Existing works to be included in elementary+ may more likely be released under CC-BY-SA already, which would make our lifes a lot easier

3. CC-BY-SA for the collection as a "creative work of its own" and an individual licence for each contained item

• Is that even possible?
  • I know that (at least in Germany) a distinct category for collection works does exist and is subject to copyright law. Thus I'd assume, that one could release the collection under a certain licence, without changing the licences of its items, as long as they have been released under a licence that allows for sharing (GPL or CC-BY-SA)
  • But seriously, I do not want to make this decision without professional advice! I am a software developer - not a lawyer :wink:
• Sounds like the most flexible solution to me, as we would not have to ask every potential contributor to re-license it for compatibility, or grant us the rights to use it

[quassy]

This becomes even more of an issue if more third-party icons should be added to the collection. I really do not if it's possible to relicense from CC-SA 3.0 to 4.0 for example; or having a collection with a whole different license...

Of course SVGs are markup code but that is just a technicality (that even a word?), PNGs are also just bits and bytes. That is nothing I would consider for choosing the license.

[Manuel-Kehl]

@ntassani to be honest: This is not the original elementary icon theme and thus we have more freedoms when it comes to respecting the HIGs.

That being said we should decide that as a community, as it is a community effort and especially @cybre and @quassy should give their opinions. Moreover I would be pleased if you @ntassani created a separate issue for that, so that we can delete these two comments, as they don't fit into this particular issue. Ok?

[Foggalong]

@mank319 @cybre @quassy

Hey, I'm a dev for Numix. Sorry to be a bit forward with this but thought I should probably way in. If you're adapting Numix status icons as part of this theme it must be licensed under the GNU GPLv3+: one of the core requirements of the license is that derivative works must retain the license.

I've submitted a pull request below which added the license file and fixes this issue :)

[Manuel-Kehl]

@Foggalong but still the question remains if it would be enough to use GPL for Numix derived icons only instead of enforcing it on all icons in the set. The icon set as such is a collection and therefore a creative work of its own. I'd suggest the following:

• [ ] create a Licenses folder
• [ ] include README.md file to explain the purpose of the folder
• [ ] include several licence files (GPL, CC-BY-SA, ...)
• [ ] maintain a list of all corresponding icons (or groups of icons) in the beginning of every file
• [ ] think about a reasonable licence for the icon set itself (probably GPL)

If this was possible (and I am quite sure it is) one could avoid all sorts of incompabilities and yet respect the licenses of the contained icons. What do you think @Foggalong, @cybre and @quassy?

[Foggalong]

That's good thinking! It also takes into account a problem I'd not thought of: the Faba icon theme is licensed under CC-BY-SA-4.0 which has the same 'ShareAlike' caveat.

As you say, you are allowed to have different files of the same project licensed differently (or even dual licensed, as Faba is). You simply need to have an additional file in with all the licenses stating which files within the project fall under each license, so that's a definite possibility. You could even combine it with the CREDIT.md (possibly making use of GitHubs tabled CSV support?) file for convenience:

Icon	License	Credit
icon1.svg	GPLv3	@Foggalong
icon2.svg	LGPL	@mank319
icon3.svg	CC-BY-SA 4.0 / LGSL	@cybre

Sorry for coming out of no where on this, I just thought I should probably speak up though because as it stands elementary+ is currently unlicensed and thus violating the ShareAlike policy that both Faba and Numix come with putting the work of the original contributors at risk.

[Manuel-Kehl]

@Foggalong Don't apologize for that. In fact I am thankful for your input! As stated above we are striving to get this issue fixed and have been hoping for someone more experienced (which you as a Numix member probably are :wink:) to express his/her opinion.

I really like the table CSV approach and suppose that we do it that way, if @quassy or @cybre don't have any objections.

[quassy]

I have no objections whatsoever and am thankful that someone more knowledgeable has weighed in. Licences are complicated.

So we should start by clearly stating the respective licences and then... still have to figure out which licence rules them all.

[Foggalong]

@mank319 Not a problem! Anything I can do to help just let me know :)

@quassy Licenses are indeed hella complicated. I had literally no idea how they worked before I started with Numix and had to sit down one afternoon and just figure out what the hell was going on :P

Reading the main license files can be a bit of a pain at times because they are mostly written by lawyers for lawyers rather than normal human beings, but TLDRLegal does a pretty good summary site if you just want a quick overview of the key points :)

[Manuel-Kehl]

I just pushed a first version of the CSV file, which still contains several gaps.

@Foggalong feel free to add/replace the author info in the Numix related files, if "Numix Team" is not specific enough :wink:

[Manuel-Kehl]

@quassy I guess it's either GPL or CC-BY-SA as "main licence" then. I'd propose sticking to GPL, as the original elementary icon theme is also licenced that way, which might simplify potential future inclusions of our work back into their project.

We can also dual licence the collection at any time if necessary.

[quassy]

@mank319 As I too hope that elementary people change their minds and third-party icons will be included, GPL v3 is problaby a must, even though I'd think CC is better for art. (Also some icons are GPL licensed.) :+1: for GPL or dual licence.

[Foggalong]

Dual licensing is a very real option for you guys. I don't think you use any icons from sources that aren't GPLv3 or CC-BY-SA and the two are as far as I'm aware perfectly compatible.

[quassy]

Apparently they are not :/

[Foggalong]

Ah, my bad! It'll have to be a case of maintaining a list then of which icons are under which license by whom.