I want to use this library in my project. Author says it is under the LGPL license, but one of its dependencies is under the EUPL license.

EUPL license isn't clear about if a closed-source application that uses the libraries inherits the EUPL license. What I understood so far is the following:

  • LGPL licence is compatible with EUPL license, so a library under LGPL license that uses another library under EUPL can be used for a closed-source commercial product.
  • It is not mandatory to put a derived product under the EUPL license if it uses a library under the EUPL license (despite it mentions that Copyleft stuff).

References I read:

In short: Can I use a library under the EUPL license for my closed-source commercial product?

  • You appear to be asking two different questions: 1) Can I use library X which is LGPL'd (and has an EUPL dependency)? 2) Can I use library Y which is EUPL'd? Those probably have different answers, so which one are you more interested in? – Ixrec Aug 5 '15 at 23:20
  • Why don't you read the actual license? The terms seem clear enough. joinup.ec.europa.eu/sites/default/files/eupl1.1.-licence-en.pdf ... In short, it appears to say that you must provide access to the source code of your work, in its entirety, when you distribute. – Robert Harvey Aug 5 '15 at 23:39
  • From what I've read so far, it seems like the only unclear part is at what point your work and the EUPL'd work count as a single work rather than two works that happen to interact. The LGPL is also unclear on this, but with the LGPL most people (probably correctly) assume that dynamic linking means separate works. I suspect the same criterion would be reasonable for dealing with the EUPL. – Ixrec Aug 5 '15 at 23:46
  • @RobertHarvey I read it and I found it rather confusing. It mentions compatibility with other licenses like GPL, and version 1.2 is compatible with LGPL. EUPL licesnse says that the library can be use in any way, but the dereived work must have its code published. But my app will use an intermediate library under LGPL, that depends on a library under EUPL. That's my confusion: LGPL allows me to use that library for closed-source projects, but the EUPL doesn't. – Broken_Window Aug 6 '15 at 13:50
  • 1
    @Ixrec my problem is tha tI'm dealing with two licences: a librry under EUPL that is used by a library under LGPL, and my app that will use the library under LGPL.That's my confusion: LGPL allows me to use that library for closed-source projects, but the EUPL doesn't. – Broken_Window Aug 6 '15 at 13:52

The answer to your question turns on that hardy perennial favorite dilemma: aggregation versus derivation. The 'intermediate-ness' of the intermediate library doesn't matter. The reason it doesn't matter is that the question is asked about the work, as a whole. I do not believe that anyone thinks that the precise order and arrangement of the call graph is important; what matters is what people think about dynamic linking. From the standpoint of, well, ldd, the EUPL library is linked into your work. Either that triggers obligations or it doesn't.

Thus, what matter is what (a) the copyright holder, and (b) a court, thinks of this. The FSF, authors of the GPL, see all dynamic linking as resulting in a derived work and thus source distribution obligations. What do the authors of the EUPL think?

If you believe Wikipedia, the dynamic linking situation of the EUPL is completely up in the air, subject to the legal breezes of each individual jurisdiction. So we have even less 'principle' to apply to predicting the legal view of dynamic linkage with an EUPL license than we do with the GPL.

Really, your best best is to ask the copyright holder of the library for her or his view of dynamic linkage. If the copyright holder gives you permission, you're good. If not, whatever anyone else thinks of the EUPL and dynamic linkage, you might be on the wrong end of a legal action.

  • thanks for the explanation. I forgot to mention, I'm in a country in South America, not in Europe! and the EUPL says that the permissions may change from country to country because of law. – Broken_Window Aug 10 '15 at 13:44

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.