Hacker News Reader

Comment by mikegerwitz | Hacker News Reader

The output of a program isn't a derivative work, so this can't be enforced with a copyright license; you'd need something else. Unless you make it a derivative work by outputting copyrighted material, but that'd be difficult with raw data.

Anyway: there's a wonderfully specific answer to this in the FAQ:

https://www.gnu.org/licenses/gpl-faq.en.html#RequireCitation

https://www.gnu.org/licenses/gpl-faq.en.html#GPLOutput

View on HN

I read this, but I honestly don’t understand it. Isn’t a license essentially a contract between the licensor and the licensee? And shouldn’t it hence be possible to write such a clause into a license? After all, lots of things are put into licenses which do not cover derivative works (e.g. conditional patent grants)?

I understand that I cannot add this to the GPL (due to the specific clauses of the GPL) and that RMS might not consider the resulting software free (though it would probably pass all of Debian’s freedom guidelines, for example), but it should be possible to have such a license in general?

The issue with adding such a restriction to the license is that it has to work within the domain of Copyright. Assuming The author of foo holds copyright on foo, but not to the output _generated_ by foo---it's an original work (assuming that foo doesn't output anything that its author does actually hold a copyright on).

I guess a good example would be a Madlib-style program, where it asks you questions and fills in the blanks in a story, often resulting in something highly amusing. The original story containing the blanks is copyrighted. The output of this program would then be a derivative work, because the original story has been modified.

But consider that the program took a story of your own (the data its processing) and output statistics, such as the word count, frequency of certain words, grammar errors, etc. This is not a derivative work. Similarly, if GNU Parallel is being used to process your input, its output isn't a derivative work.

With that said, you can have a separate EULA-type thing---which is _outside_ the domain of copyright---that imposes these terms. But that is incompatible with the terms of the GPL.

This is not true, or at least not universally true. For example, gameplay videos are also considered copyrighted as they contain assets and other copyrighted elements. Your "mad libs" example probably falls under a similar classification. A completed Mad Libs would still contain large distinctive elements of a copyrighted work.

In these cases, the EULA actually may contain clauses that allow you to distribute gameplay videos. But if they do not contain exemptions, it's copyright that will restrain you, not the EULA.

http://www.develop-online.net/analysis/uploading-gameplay-co...

https://support.google.com/youtube/answer/138161?hl=en

Now in the specific case of GNU Parallel, I don't see how the output would contain any distinctive elements of the original program. As a counterexample you could not use GNU parallel to process its own source code and end up with your own copyright on the output, however.

> Your "mad libs" example probably falls under a similar classification.

Yes, by stating that it's a derivative work, I meant that the output would be subject to the Madlibs copyright.

GNU Parallel's output isn't subject to the GPL.

The scope of restrictions in a license don't have to fall only within copyright. Proprietary licenses routinely limit what you can do with or to the software, and don't restrict themselves to derivative works: the license can have "teeth" simply by revoking your copyright license to the original, unmodified software.

If you're thinking, well that still only is effective if your use involves making copies of the software, note that US courts have held that just using software and thereby causing it to be copied into RAM counts as making a copy for the purpose of copyright law (see MAI Systems v. Peak).

Reply on news.ycombinator.com