Distributing under 3-clause BSD License?

  • Although LGPL code like the Qt framework is permitted to be linked with any other-licensed code, LGPL adds additional requirements for the combined work as LGPL disallowed redistribution without the LGPL license. This situation is causing a problem with some open-source academic application that I am working on. I would be able to solve this by distributing my work under the 3-clause BSD license but it seems that would require paying for a commercial license for Qt. Is this correct? It sounds a bit odd...

  • Lifetime Qt Champion


    For such compatibility question you should rather ask the folks at fsf.org or a lawyer.

  • The (in)compatibility was brought to my attention by a project manager of a research institute who talked to a lawyer. My main question is whether I would need a commercial license for Qt if I want to distribute my Qt based code under BSD license instead of the default LGPL license. If so, I may have to switch to a different GUI framework.

  • Lifetime Qt Champion


    AFAIK, the BSD three clause is compatible with LGPL but not GPL and the BSD two clause is compatible with both.

  • Qt Champions 2017

    Disclaimer: I AM NOT A LAWYER!

    As @SGaist said, you should talk to an actual attorney to be completely sure.

    However as far as I understand licenses, your code's licensing has no bearing on Qt's code licensing (provided you use dynamic linking). I.e. LGPL is specifically tailored for libraries and I see no conflict between distributing your code with the BSD license, while distributing (or not, which would be my preferred approach by the way) Qt with the LGPL. I see no conflict between LGPL (it's point number 4 about combined works) and the 3-clasuse BSD, but again talk to a lawyer to avoid any funny business.

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