An FSF statement by Richard Stallman, published on April 11, 2016.
This article explains some issues about the meaning and enforcement of the GNU General Public License. The specific occasion for this article is the violation of combining Linux with ZFS, and that concerns specifically GNU GPL version 2; however, most of the points apply to all versions of the GNU GPL and to the GNU Affero GPL as well. “GPL” or “GNU GPL” refers to any version of either of those.
While stating our understanding of the meaning of the license that we publish, we must point out that this is not legal advice.
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