Putting license in each code file?

licensing

33,668

Solution 1

A single one outside the code, please! I don't know about the others, but I hate seeing the same thing on top of every file.

I think I've read it a few times, just by page_down-ing through it.

Solution 2

EULA is the wrong term here, as the people looking at source code usually are not end users.

Legally, it makes no difference either; copyright does not need to be declared explicitly.

Basically, all you achieve is a lower risk of people accidentally violating your license terms. You'll have to decide how important that is to you.

I'd say the best compromise is to put a very short header containing a link (absolute URL as well as relative within the project) to the full license text into each source code file. That way, anyone who cares about the license knows where to find it (ideally, people who're willing to pay massive license fees; you certainly want those people to be able to contact you!)

Solution 3

It might depend on the license. The GPL distinguishes between preamble and license. It clearly states, that the (annoying) preamble must be part of the code:

Can I omit the preamble of the GPL, or the instructions for how to use it on your own programs, to save space?

The preamble and instructions are integral parts of the GNU GPL and may not be omitted. In fact, the GPL is copyrighted, and its license permits only verbatim copying of the entire GPL. (You can use the legal terms to make another license but it won't be the GNU GPL.) (1)

Source: 1) http://www.gnu.org/licenses/gpl-faq.html#GPLOmitPreamble

A free ebook from ifrOSS explains and comments the GPL 2 in german language. There is another one for GPL 3

For a well founded answer you should ask for a legal advice which is not available on sx. If you can not find a lawyer for your (open source) project, have a look at the FSFE legal network.

Solution 4

No, you don't have to put the license in each source code file.

If you look closer, most FOSS applications don't do that either. They put a copyright statement at the top of each file and a short sentence telling you what license the file is under and where you can find the full text of the license. They usually point you to the COPYING or LICENSE file containing the full text of the license and/or to a website that contains the full text (in case the COPYING file isn't there anymore).

Like Michael Borgwardt said in his answers, legally you don't have to do this. But it is advisable for source code that you intend to distribute since people can immediately see who has the copyright and what the license is.

Solution 5

I think the reasoning behind putting it in each file is a legal one. If the agreement is in each file, there is no chance of someone stumbling across a piece of code without being exposed to the license.

It may not be a good one, but all the big boys use it so if it's just visual pain, I would look for a better reason not to do the same.

If you're using GPL this is more of an issue, but if you're using public domain licenses like BSD or MIT, I don't think you really care what people do with the code anyway. I suppose it depends on how strict your license is.

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33,668

Joan Venge

Professional hitman.

Updated on September 11, 2020

Comments

Joan Venge over 3 years

I find it unnecessarily duplicated to have it in each code file, but I see it on most open source projects. Should I do that same, or just include a single license outside the code?
- om-nom-nom over 8 years
  
  See also programmers.stackexchange.com/questions/125836/…
- Evgeni Sergeev about 8 years
  
  You've got to exclude warranty in each source file, otherwise you might get caught out. (Note that a proper editor, like Vim, can be easily configured to fold the warranty exclusion boilerplate for you out of sight automatically.)
Joan Venge almost 15 years

Thanks. It's gonna be open source.
Venedictos almost 15 years

If it's something short like BSD/Apache/MIT, then it should be okay.
strager almost 15 years

I disagree with Zifre. Any repeated license at the top is irritating for me.
Kekoa almost 15 years

Copyright may not need to be explicit, but what about copy-left?
Venedictos almost 15 years

@kekoav: copyleft is less restrictive than copyright. By default, you can't make derivative works.
Joan Venge almost 15 years

Btw Michael your idea to put a link is good.
Joan Venge almost 15 years

You mean a url, right? In that case would be complain that they didn't have internet, so didn't know the license?
Lasse V. Karlsen almost 15 years

In a dispute, that would not be a valid argument. If told that there is a license, and how to retrieve it, you can't site technical barriers that are your fault that prevented you from seeing the license.
darjab almost 15 years

Well, in that case, just point in each file that upon continuing with it, you agree to the licence in file licence.txt. But don't copy/paste the same text in each file. I sometimes find files with code shorter then the licence.
Jonathan Leffler almost 15 years

It's reasonable and sensible to identify which license each source file was released under, because the file might be separated from the rest of the code (reuse - encouraged, in general, by Open Source), and if the file contains no information about the licence, it's trickier to track back to the correct licence. But the whole licence in each file - no; that would be grotesque for GPL or LGPL. As already suggested, for the short licences, it's a nuisance to have the actual licence text in the file, but it's a judgement call. But it is sensible to identify which licence it's released under.
Michael Borgwardt almost 15 years

"Copyleft" is slang for the the basic idea of GPL to "subvert" copyright restrictions from within, i.e. using your rights as a copyright holder to grant a license to anyone to use your code freely, but force them to release THEIR code which is based on yours under the same license.
Esko Luontola almost 15 years

I just updated the file headers in my project to have only three lines: copyright, name of license, and an URL to the license text. It shorted my headers from 26 lines (BSD) to 3 lines. :)
darjab almost 15 years

@Jonathan Leffler - Nice point Jonathan. Esko's approach takes care of that problem also, just include the files of all licences you're using in your code, and point to them. I prefer to see even the short licences in separate files.
Liran Orevi almost 15 years

You can create a hard-coded string to contain the license, so it'll appear on the binary, but that's probably too much :).
jmucchiello almost 15 years

Yes, but a "copyleft" work is still copyrighted. Without copyright laws, the copyleft license does not work.
Michael Borgwardt almost 15 years

Correct; but in this context, as Zifre said, it does not matter. If you don't know the license under which a particular piece of code was published, you have to assume you're not allowed to use it at all. So as the publisher, you don't have to go to extra lengths to make people read the license.
Kekoa almost 15 years

Yeah, I agree that it works just as well that way, especially for long licenses. Even though it may not be legally essential, or even supportable in court, a reference to your license is at the very least good to inform people without them having to go search around for what license the code is under.
Joan Venge almost 15 years

Thanks, so copyright is different?
Ivan_Bereziuk almost 15 years

INAL but a license is a contract between you and the user/customer. Copyright is an assertion of ownership of a piece of a written work. Someone could pick up a fragment of your code and reasonably claim it wasn't copyright because the notice was missing. Dont worry though "Copyright Joe Soap (Cleansoft Inc.)" is all you need.
ubi over 14 years

how do you automate last revision date?
Jasper almost 14 years

You're so wrong about that. While it's generally good to indeed add copyright notices everywhere just to be clear, but that doesn't make it fair game to "assume it wasn't copyrighted" Because you know EVERYTHING is copyrighted. When someone obtains source code, he may find a license statement that allows him to use it, or he may find out that it is in the public domain for one reason or another. If he doesn't though it is copyrighted and can't be copied. Copyright is an automatic thing and it's good to mention it, but not doing so doesn't mean you lose it...
fny over 11 years

Would it be permissible to mention the license at the top of the file and include it in a comment block at the bottom? E.g. "Distributed under the MIT License, Available at the End of this Document \n...Code...\n Permission is hereby granted.... WARRANTY... EOF"
Jonas Stein about 11 years

This answer is marked as solution, but in my oppinion the question is still open as long we have no evidence for the legal situation. Perhaps a lawyer can add a link to a court decision.
R. van Twisk over 10 years

I had once a issue with some source code where they copyright holder told me : No no, that files is NOT on this and that license, even though the large file was added as the base. Just saying that it's a fray area where a person not holding the copyright might run into issues and get whissled back. Please add a small copyright on each file!
darjab over 10 years

@ries - Just as you said; you "once had an issue"; those situations are relatively rare. Can we take this as a general guideline and deal with those rare cases on a case-by-case basis?
toxalot about 10 years

Preamble and instructions are part of the full license, but nothing says you have to put the full license in every file. [...] attach the following notices to the program. - following notices is only a small section of the full license. safest to attach them to the start of each source file - safest but not required. each file should have at least the "copyright" line and a pointer to where the full notice is found. - only requirement is the copyright line with a pointer to the rest. It's fine to put the full license in one separate file.
toxalot about 10 years

And I'd argue that should != must.
straya over 7 years

A small copyright can help if/when individual files (or portions of) are copied for reuse, but it should not be necessary! The person copying an individual file (or portion of) is responsible for including the LICENSE in that copy when they do it.
user136036 over 3 years

You are wrong. You are neither forced to add the full license to the code (not that anyone would), but you are also NOT forced to add any note in your code at all (the famous GPL header in files) - though it might make sense. What you quote simply says is, that you cannot rip the GPL text apart.
User almost 3 years

This is so stupid, why the text of the license is not simply adjusted to apply it by default to all the files in the project / repository which has the license? It should be possible to come up with a good default. I absolutely hate having non-domain related noise in my code.
Ryan Hart almost 2 years

I'm over a decade late on commenting here, but this was the most fitting answer that applied to my situation. I'm getting involved in development work in a new community where I noticed everyone was including their license at the top of every script. But it makes sense now that those scripts are being copied and distributed among end users who just run the scripts have no idea what they do when they run them. After that script passes hands enough times, an external license file would have got long forgotten about.