I'm not talking about distributing any GPL software. I'm talking about using the output of a GNU GPL software in commercial purposes.

For example: I use kdenlive for my video editing and inserting titles in my videos. So basically, the titles are the text, and in the gnu website faq they are saying that when a software covers some part of its input in to the output so the output covers the same licence.

So in my case the titles are the input which I put in my videos so how do I upload and monetize them because youtube gives only two licence options for videos: standard and creative common licence.

  • 4
    In general, input and output of a GPL'd program are not covered by the GPL. Why would they be? Even the Gnu Compiler Collection doesn't have this requirement, and it produces programs as output. Feb 25, 2016 at 15:20
  • I don't know why you got a downvote - the question is so hot the GNU FAQ has several entries explaining it in a dozen paragraphs!
    – gbjbaanb
    Feb 25, 2016 at 15:29
  • @gbjbaanb: He asked the same question here yesterday (many questions in the same post, actually) which was closed and deleted. This one is much better, though. Feb 25, 2016 at 15:33
  • Surely the whole output of GPL compilers like GCC is automatically under GPL (the compiler also adds a license file to that output, and automatically uploads a copy of the compiled source code to the FSF, didn't you notice? (Just kidding ;-))) ).
    – Doc Brown
    Feb 25, 2016 at 15:34
  • If you run GNU grep on the source code for a program, would you expect that program to become GPLed?
    – dan04
    Feb 26, 2016 at 0:08

2 Answers 2


That's not what that clause is about.

Is there some way that I can GPL the output people get from use of my program? For example, if my program is used to develop hardware designs, can I require that these designs must be free? (#GPLOutput)

In general this is legally impossible; copyright law does not give you any say in the use of the output people make from their data using your program. If the user uses your program to enter or convert his own data, the copyright on the output belongs to him, not you. More generally, when a program translates its input into some other form, the copyright status of the output inherits that of the input it was generated from.

So the only way you have a say in the use of the output is if substantial parts of the output are copied (more or less) from text in your program. For instance, part of the output of Bison (see above) would be covered by the GNU GPL, if we had not made an exception in this specific case.

As the authors state, copyright does not provide a means to restrict the output of a program to the licence terms that apply to the program itself. That is only possible if the output consists of part of the source code of the GPL'd program. (For instance, YACC or Bison generate source code for lexers and parsers, and their output contains large parts of the source code of YACC and Bison themselves.)

But that is not the case for you. The source code of a KDEnlive is GPL'd, but the output you produce with is is not derived from its source code, it's derive from the subtitles you feed into it. Therefore this clause doesn't apply to you.

  • 1
    so it means i m free to give any licence to my output or use the output for commercial purpose
    – TardyT
    Feb 25, 2016 at 21:00
  • @TardyT Exactly.
    – Andres F.
    Feb 26, 2016 at 0:49

The GPL FAQ says that the output is specifically not covered by the same licence as the program, except when some text or art that is part of the program is output too - for example some large block of text that is embedded in the program is output, the original copyright of the program text is still program text and therefore still covered by the same licence.

The output of a program is not, in general, covered by the copyright on the code of the program. So the license of the code of the program does not apply to the output, whether you pipe it into a file, make a screenshot, screencast, or video.

If the art/music is under the GPL, then the GPL applies when you copy it no matter how you copy it. However, fair use may still apply.

So in your case the titles generated are not GPL and are free to use.

  • thanks your answer is useful and what do u mean by large block of text can u give me some examples
    – TardyT
    Feb 25, 2016 at 20:51

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