mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-11-14 13:21:28 +00:00
211 lines
6.8 KiB
XML
211 lines
6.8 KiB
XML
<sect1 id="chapter-legal">
|
|
<title id="title-legal">GStreamer Legal Issues</title>
|
|
<para>
|
|
This part of the FAQ is based on a series of questions we asked the FSF
|
|
to understand how the GPL works and how patents affects the GPL. These
|
|
questions were answered by the <ulink url="http://www.fsf.org/">
|
|
FSF lawyers</ulink>, so we view them as the
|
|
final interpretation on how the GPL and LGPL interact with patents in our
|
|
opinion. This consultancy was paid for by
|
|
<ulink url="http://www.fluendo.com/">Fluendo</ulink>
|
|
in order to obtain clear and quotable answers. These answers were certified
|
|
by the FSF lawyer team and verified by FSF lawyer and law professor Eben Moglen.
|
|
</para>
|
|
|
|
<qandaset>
|
|
|
|
<qandaentry>
|
|
<question id="legal-distribute-three">
|
|
<para>
|
|
Can someone distribute the combination of
|
|
<itemizedlist>
|
|
<listitem><para>GStreamer, the LGPL library</para></listitem>
|
|
<listitem><para>Totem, a GPL playback application</para></listitem>
|
|
<listitem><para>The binary-only Sorenson decoder</para></listitem>
|
|
</itemizedlist>
|
|
together in one distribution/operating system ? If not, what
|
|
needs to be changed to make this possible ?
|
|
</para>
|
|
</question>
|
|
|
|
<answer>
|
|
<para>
|
|
This would be a problem, because the GStreamer and Totem licenses would
|
|
forbid it. In order to link GStreamer to Totem, you need to use section
|
|
3 of the LGPL to convert GStreamer to GPL. The GPL version of GStreamer
|
|
forbids linking to the Sorenson decoder. Anyway, the Totem GPL
|
|
license forbids this.
|
|
</para>
|
|
|
|
<para>
|
|
If the authors of Totem want to permit this, we have an
|
|
exception for them: the controlled interface exception from the FAQ.
|
|
The idea of this is that you can't get around the GPL just by including
|
|
a LGPL bit in the middle.
|
|
</para>
|
|
|
|
</answer>
|
|
</qandaentry>
|
|
|
|
<qandaentry>
|
|
<question id="legal-binary-plugin">
|
|
<para>
|
|
Suppose Apple wants to write a binary-only proprietary
|
|
plugin for GStreamer to decode Sorenson video, which will be shipped
|
|
stand-alone, not part of a package like in the question above.
|
|
Can Apple distribute this binary-only plugin ?
|
|
</para>
|
|
</question>
|
|
|
|
<answer>
|
|
<para>
|
|
Yes, modulo certain reverse engineering requirements in section 6 of
|
|
the LGPL.
|
|
</para>
|
|
</answer>
|
|
</qandaentry>
|
|
|
|
<qandaentry>
|
|
<question id="legal-gpl-program">
|
|
<para>
|
|
If a program released under the GPL uses a library that
|
|
is LGPL, and this library can dlopen plug-ins at runtime, what are the
|
|
requirements for the license of the plug-in ?
|
|
</para>
|
|
</question>
|
|
|
|
<answer>
|
|
<para>
|
|
You may not distribute the plug-in with the GPL application.
|
|
Distributing the plug-in alone, with the knowledge that it will be used
|
|
primarily by GPL software is a bit of an edge case. We will not advise you
|
|
that it would be safe to do so, but we also will not advise you that it
|
|
would be absolutely forbidden.
|
|
</para>
|
|
</answer>
|
|
</qandaentry>
|
|
|
|
<qandaentry>
|
|
<question id="legal-safe-countries">
|
|
<para>
|
|
Can someone in a country that does not have software patents distribute
|
|
code covered by US patents under the GPL to people in, for example, Norway ?
|
|
If he/she visits the US, can he/she be arrested ?
|
|
</para>
|
|
</question>
|
|
|
|
<answer>
|
|
<para>
|
|
Yes, he can.
|
|
No, there are no criminal penalties for patent infringement in the US.
|
|
</para>
|
|
</answer>
|
|
</qandaentry>
|
|
|
|
<qandaentry>
|
|
<question id="legal-unsafe-countries">
|
|
<para>
|
|
Can someone from the US distribute software covered by
|
|
US patents under the GPL to people in Norway ? To people in the US ?
|
|
</para>
|
|
</question>
|
|
|
|
<answer>
|
|
<para>
|
|
This might infringe some patents, but the GPL would not forbid it
|
|
absent some actual restriction, such as a court judgement or agreement.
|
|
The US government is empowered to refuse importation of patent
|
|
infringing devices, including software.
|
|
</para>
|
|
</answer>
|
|
</qandaentry>
|
|
|
|
<qandaentry>
|
|
<question id="legal-gpl-library-patents">
|
|
<para>
|
|
There are a lot of GPL- or LGPL-licensed libraries that
|
|
handle media codecs which have patents. Take mad, an mp3 decoding library,
|
|
as an example. It is licensed under the GPL. In countries where patents
|
|
are valid, does this invalidate the GPL license for this project ?
|
|
</para>
|
|
</question>
|
|
|
|
<answer>
|
|
<para>
|
|
The mere existence of a patent which might read on the program does not
|
|
change anything. However, if a court judgement or other agreement
|
|
prevents you from distributing libmad under GPL terms, you can not
|
|
distribute it at all.
|
|
</para>
|
|
|
|
<para>
|
|
The GPL and LGPL say (sections 7 and 11):
|
|
<quote>If you cannot distribute so as to satisfy simultaneously your
|
|
obligations under this License and any other pertinent obligations, then
|
|
as a consequence you may not distribute the Library at all.</quote>
|
|
</para>
|
|
</answer>
|
|
</qandaentry>
|
|
|
|
<qandaentry>
|
|
<question id="legal-gpl-court-judgment">
|
|
<para>
|
|
So let's say there is a court judgement. Does this mean that the GPL license is
|
|
invalid for the project everywhere, or only in the countries where it conflicts
|
|
with the applicable patents ?
|
|
</para>
|
|
</question>
|
|
|
|
<answer>
|
|
<para>
|
|
The GPL operates on a per-action, not per-program basis. That is, if
|
|
you are in a country which has software patents, and a court tells you
|
|
that you cannot distribute (say) libmad in source code form, then you
|
|
cannot distribute libmad at all. This doesn't affect anyone else.
|
|
</para>
|
|
</answer>
|
|
</qandaentry>
|
|
|
|
<qandaentry>
|
|
<question id="legal-gpl-and-binary">
|
|
<para>
|
|
Patented decoding can be implemented in GStreamer either by
|
|
having a binary-only plugin do the decoding, or by writing a plugin
|
|
(with any applicable license) that links to a binary-only library.
|
|
Does this affect the licensing issues involved in regards to GPL/LGPL?
|
|
</para>
|
|
</question>
|
|
|
|
<answer>
|
|
<para>
|
|
No.
|
|
</para>
|
|
</answer>
|
|
</qandaentry>
|
|
|
|
<qandaentry>
|
|
<question id="legal-gpl-patent-distribution">
|
|
<para>
|
|
Is it correct that you cannot distribute the GPL mad library to
|
|
decode mp3's, *even* in the case where you have obtained a valid license
|
|
for decoding mp3 ?
|
|
</para>
|
|
</question>
|
|
|
|
<answer>
|
|
<para>
|
|
The only GPL-compatible patent licenses are those which are open to
|
|
all parties posessing copies of GPL software which practices the
|
|
teachings of the patent.
|
|
</para>
|
|
|
|
<para>
|
|
If you take a license which doesn't allow others to distribute
|
|
original or modified versions of libmad practicing the same patent
|
|
claims as the version you distribute, then you may not distribute at
|
|
all.
|
|
</para>
|
|
</answer>
|
|
</qandaentry>
|
|
</qandaset>
|
|
</sect1>
|