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For multiple copyleft licenses

When publishing as OSS, if the dependent packages have different copyleft licenses, such as GPL and MPL, which license should my software apply?

I wondered if both should be applied and investigated the dual license, but it was said that the user could choose either one, and I thought that the one who did not choose would be a license violation. I also thought that it would be complicated if there were two or more types of copyleft licenses in a dependency relationship.

If i know more about it, I would appreciate it if you could let me know.

  • Answer # 1

    It was said that the user could choose either one, and I thought that the one who did not choose would violate the license.

    No, it is possible (usually) to adopt only one of the dual licenses, as it can be used under the "either condition" presented. You don't have to think about "the one who wasn't selected".

    I also thought that it would be complicated if there were two or more types of copyleft licenses in a dependency relationship.

    Yes, that's right. When combining libraries with conflicting licensesCannot be distributedIt may be.


    That's all I can say in abstract theory, so it is necessary to pick up the conditions and think specifically, such as "A's library is GPL/MPL, B is 2-clause BSD".