During my Ph.D. work at a university, I followed up on someone else's doctoral work (I am no longer associated with that university). This person provided me with the source code for his work. I subsequently discovered that this source code is a slightly modified copy of some publicly available sources, which have a GPL license. The modifications are mostly some instruction toggling/rebracketing and variable renaming. Just a few instructions contain slight modifications (that I personally do not find any more justifiable than the variable renaming). Moreover, in the versions that this person gave me, the authorship headers of the original authors are replaced by his own and the copyright mentions of the university in question are also added. The GPL license notice, which is present in the original sources, is removed from all but one package.

I had reported these observations to my supervisors (who also supervised the work of the person in question), but they sought to suppress the matter and warned me of legal actions if I reported this matter any further (hence I am not reporting it directly to the university, which by the way does not seem to have an ethics committee). I'll note that these observations in the source code are part of several issues that I observed in this person's work (that involves several publications and his doctoral dissertation; I'll probably ask for advice regarding that in separate questions).

Is it legally safe if I publicly share the source code provided by this person along with the links to the online available original sources? The code was transferred to me by this person through a sharing link that is no longer available. I can only prove that I reported my observations to my supervisors as well as to this person (he responded by reaffirming that the source code was developed at the university in question and refused any further communication). I'll note that an engineer at the university trans-coded some of the source code in question for use in a commercial product for which the university had a collaboration with a private firm.


I am also a co-author of this person in a couple of publications. This collaboration was supposed to be a sort of transition/continuation, at the beginning of my doctoral program and the end of his, of his reportedly high-functioning work. When I discovered several anomalies, I requested my supervisors to get these publications retracted. My detailed response is at the PubPeer page of one of these publications. In my response, I have also shared some of my email exchanges with my co-authors. These exchanges lend support for raising the issue about the source code, without actually sharing it.

I was quite shocked when this person suggested that he not only did not have to acknowledge the use of the existing ideas/solutions but also considered their mere mention to be optional (his exact words: "You do not have to acknowledge but you can cite them"). Concerns about the acknowledgment of the sources, the soundness of ideas, and various peculiarities in results are raised on the PubPeer pages of his several publications.

Considering my question about the legal aspect, the comments about this being a legal question are right. However, I would also like to know if publishing this source code would be objectively helpful (a part of it was given to me with the GPL notice intact). Some comments on the above-mentioned PubPeer pages compare long extracts and a large number of equations from the publications to point out something that can be noticed in a glance by comparing the source codes.

Thanks for the discussion in response to my query! Depending on the input in the comments, I might post this part as a separate question.

  • 25
    "Legally safe" is a legal question, not an academic one. But it all seems fairly trivial. Just use the correct GPL licensed versions exclusively. I don't see any advantage in what you're proposing.
    – MSalters
    Commented Jan 31, 2020 at 11:58
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    Use the publicly available versions, no issues then.
    – Solar Mike
    Commented Jan 31, 2020 at 12:33
  • 7
    "is it legally safe if I publicly share the source codes provided by this person" why do you want to do this at all? What do you gain by publicly posting his work?
    – Daniel K
    Commented Jan 31, 2020 at 12:41
  • 1
    Never having used the services of an ombudsperson before, I'd be interested to know from other community members if this is an appropriate issue to discuss with an ombudsperson (assuming one is available)
    – anjama
    Commented Feb 2, 2020 at 2:57
  • 2
    The code was given to you, likely with no intent to distribute. If neither the ex colleague nor you release the code, I see no copyright violation. Like if I doodle the logo of a famous brand in the margin of a book I'm reading.
    – PatrickT
    Commented Feb 2, 2020 at 23:42

3 Answers 3


With the caveat that I am not a lawyer, the answer is "no".

You have:

  • code A, which is GPL-licensed
  • code B, which is a derivative work of A and not GPL-licensed.

The GPL license requires that all derivative works are also GPL-licensed. As B does not carry the GPL license, it is a copyright violation and (depending on jurisdiction) it is probably illegal for you to distribute it.

If the changes needed are small, your simplest way forward would be to take code A, and modify it yourself as needed to make code C, while keeping it GPL-licensed, and release that.

EDIT: As noted in the comments, it is possible that A had two licenses: The GPL, and another license granted specifically to the author of B which permitted them to change the names and redistribute without GPL. This seems very unlikely, but you should consider the possibility if considering accusations of any sort.

  • 9
    There is an exception to this, however. It is possible that the code was originally available under another license, and then later used in a GPL project, where it also received a GPL license. In this case the code could still be freely available - you can't tell unless you know the original source of where the code was written. (And yes, I've seen instances of this in practice.)
    – Nathan S.
    Commented Jan 31, 2020 at 16:19
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    Not only is it illegal for you to distribute "code B", it was illegal for the author of B to give you a copy (the modifications described violate all four requirements of the "conveying modified source versions" clause of the GPL), and because of that violation, the author of B no longer has the right to use it.
    – Mark
    Commented Jan 31, 2020 at 21:20
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    @Mark That assumes that the author of B had no other license to code A. That is merely an assumption. Commented Feb 1, 2020 at 22:22

What that person did, was not just plagiarism, but also copyright infringement. They took a GPL licensed work (legal), modified it (still legal), published it, but not under the GPL license (copyright infringement), and claimed it as their own work (plagiarism).

If you wanted to be nasty, you could tell the original author of the code about this, and if that person decides to sue for copyright infringement, that university and everyone involved is in deep trouble. I would be curious to know whether anyone ever managed to get their thesis revoked, not for plagiarism, but for copyright infringement plus plagiarism.

No, you are absolutely not allowed to use this software in any way, shape or form, unless you get the permission of the copyright holder. Or if the person producing the modified code gives you another copy including the GPL license.

I cannot understand how a university would have allowed this. Quoting some text without reference is bad enough, but actively removing copyright notices, license information, and author names, that's an entirely different level.

  • 11
    I would +1 this if not for "If you wanted to be nasty". You should report this to the copyright holder. Commented Jan 31, 2020 at 23:57
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    my supervisors... warned me of legal actions if I reported this matter any further - Your supervisors are extorting you to abet copyright violation. They are more despicable than the copyright violator they are protecting! - You don't need to be a hero and right every wrong but be mindful of what villainy you are ignoring. Commented Feb 1, 2020 at 3:09
  • 3
    Why is this being nasty at all? The purpose of the GPL is to protect free code from being sold by money-grubbers or used to cheat or lie. Invoking it is just being right, not to say protecting other people.
    – user21820
    Commented Feb 2, 2020 at 15:52
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    @MazurkaFahr: You should finish your PhD as fast as possible, get completely out of that toxic wastebin, and then if you agree that such unethical behaviour should not be condoned, you should anonymously publicize the university name. Just make sure they cannot retaliate at you. Sad to say, but bad people never suddenly turn good, and you need to protect yourself first. But if you can, eventually exposing them will do everyone else a lot of good.
    – user21820
    Commented Feb 2, 2020 at 15:57
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    Re “I cannot understand how a university would have allowed this.”: While I’m aware experimental sciences have quite stringent ethics procedures, the subjects I work in (maths and CS) are essentially self-policing on ethical issues, with little or no university-level oversight, and my impression is that many researchers are much more lax about checking licensing issues than about checking academic plagiarism. I’m confident that a serial offender would get caught sooner or later, but I can easily see how a one-off incident could get through without anyone noticing.
    – PLL
    Commented Feb 2, 2020 at 15:59

As I haven't seen either code, and as a university professor myself, based on what you have mentioned, I would recommend that you consult with the GPL licensing authority.... They can decide about the proper respond both legally and ethically

  • 3
    There is no "GPL licensing authority". The Free Software Foundation are the originators of it, I think, but they're not responsible for enforcement.
    – Flyto
    Commented Feb 2, 2020 at 16:17

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