--- short-description: Patents, Licenses and legal F.A.Q. ... # Legal information ## Installer, default installation The installer (Microsoft Windows and MacOSX) and the default installation (GNU/Linux) contain and install the minimal default installation. At install time or later, the downloading of optional components is also possible, but read on for certain legal cautions you might want to take. All downloads are from the [gstreamer.freedesktop.org](http://gstreamer.freedesktop.org) website. ## Licensing of GStreamer GStreamer minimal default installation only contains packages which are licensed under the [GNU LGPL license v2.1](http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html). This license gives you the Freedom to use, modify, make copies of the software either in the original or in a modified form, provided that the software you redistribute is licensed under the same licensing terms. This only extends to the software itself and modified versions of it, but you are free to link the LGPL software as a library used by other software under whichever license. In other words, it is a weak copyleft license. Therefore, it is possible to use GStreamer to build applications that are then distributed under a different license, including a proprietary one, provided that reverse engineering is not prohibited for debugging modifications purposes. Only the pieces of GStreamer that are under the LGPL need to be kept under the LGPL, and the corresponding source code must be distributed along with the application (or an irrevocable offer to do so for at least three years from distribution). Please consult section 6 of the [LGPL](http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html) for further details as to what the corresponding source code must contain. Some portions of the minimal default installation may be under different licenses, which are both more liberal than the LGPL (they are less strict conditions for granting the license) and compatible with the LGPL. This is advised locally. ## Optional packages There are two types of optional packages (GPL and Patented), which are under a different license or have other issues concerning patentability (or both). #### GPL code Part of the optional packages are under the GNU GPL [v2](http://www.gnu.org/licenses/old-licenses/gpl-2.0.html). This means that you cannot link the GPL software in a program unless the same program is also under the GPL, but you are invited to seek competent advice on how this works in your precise case and design choices. GPL is called “strong copyleft” because the condition to distributed under the same license has the largest possible scope and extends to all derivative works. #### Patents Certain software, and in particular software that implements multimedia standard formats such as MP3, MPEG 2 video and audio, h.264, MPEG 4 audio and video, AC3, etc, can have patent issues. In certain countries patents are granted on software and even software-only solution are by and large considered patentable and are patented (such as in the United States). In certain others, patents on pure software solutions are formally prohibited, but granted (this is the case in many European countries), and in others again are neither allowed nor granted. It is up to you to make sure that in the countries where GStreamer is used, products are made using it and product are distributed, a license from the applicable patent holders is required or not. Receiving GStreamer – or links to other downloadable software – does not provide any license expressed or implied over these patents, except in very limited conditions where the license so provides. No representation is made. In certain cases, the optional packages are distributed only as source code. It is up to the receiver to make sure that in the applicable circumstances compiling the same code for a given platform or distributing the object code is not an act that infringes one or more patents. ## Software is as-is All software and the entire GStreamer binaries are provided as-is, without any warranty whatsoever. The individual licenses have particular language disclaiming liability: we invite you to read all of them. Should you need a warranty on the fact that software works as intended or have any kind of indemnification, you have the option to subscribe a software maintenance agreement with a company or entity that is in that business. ## Licensing of code contributed to GStreamer itself GStreamer is a plugin-based framework licensed under the LGPL. The reason for this choice in licensing is to ensure that everyone can use GStreamer to build applications using licenses of their choice. To keep this policy viable, the GStreamer community has made a few licensing rules for code to be included in GStreamer's core or GStreamer's official modules, like our plugin packages. **We require that all code going into our core packages is LGPL.** For the plugin code, we require the <B>use of the LGPL for all plugins written from scratch or linking to external libraries</B>. The only exception to this is when plugins contain older code under the BSD and MIT license. They can use those licenses instead and will still be considered for inclusion, we do prefer that all new code written though is at least dual licensed LGPL. We do not accept GPL code to be added to our plugins modules, but we do accept LGPL-licensed plugins using an external GPL library for some of our plugin modules. The reason we demand plugins be licensed under the LGPL, even when they are using a GPL library, is that other developers might want to use the plugin code as a template for plugins linking to non-GPL libraries. We also accept dual licensed plugins for inclusion as long as one of the licenses offered for dual licensing is the LGPL. We also do not allow plugins under any license into our core,base or good packages if they have known patent issues associated with them. This means that even a contributed LGPL/MIT licensed implementation of something which there is a licensing body claiming fees for, those plugins would need to go into our gst-plugins-ugly module. All new plugins, regardless of licensing or patents tend to have to go through a period in our incubation module, gst-plugins-bad before moving to ugly, base or good. ## Frequently Asked Questions #### What licenses are there? GStreamer binaries contain software under various licenses. See above. #### How does this relate to the packaging system? The packaging is only a more convenient way to install software and decide what's good for you. GStreamer is meant to be modular, making use of different modules, or plugins, that perform different activities. We provide some of them by default. Others are provided as an additional download, should you elect to do so. You could do the same by finding and downloading the same packages for your own platform. So it is entirely up to you to decide what to do. Also, we note that GStreamer elements are divided into different packages, roughly following the licensing conditions attached to the same. For instance, the codecs-gpl package contains GPL licensed codecs. All the packages installed by default, conversely, are licensed under the LGPL or a more liberal license. This division is provided only for ease of reference, but we cannot guarantee that our selection is 100% correct, so it is up to the user to verify the actual licensing conditions before distributing works that utilize GStreamer. #### Can I / must I distribute GStreamer along with my application? You surely can. All software is Free/Open Source software, and can be distributed freely. You are not **required** to distribute it. Only, be reminded that one of the conditions for you to use software under certain licenses to make a work containing such software, is that you also distribute the complete source code of the original code (or of the modified code, if you have modified it). There are alternative ways to comply with this obligation, some of them do not require any actual distribution of source code, but since GStreamer contains the entire source code, you might want to include it (or the directories containing the source code) with your application as a safe way to comply with this requirement of the license. #### What happens when I modify the GStreamer's source code? You are invited to do so, as the licenses (unless you are dealing with proprietary bits, but in that case you will not find the corresponding source code) so permit. Be reminded though that in that case you need to also provide the complete corresponding source code (and to preserve the same license, of course). You might also consider to push your modifications upstream, so that they are merged into the main branch of development if they are worth it and will be maintained by the GStreamer project and not by you individually. We invite you not to fork the code, if at all possible. The Cerbero build system has a "bundle-source" command that can help you create a source bundle containing all of the complete corresponding machine readable source code that you are required to provide. #### How does licensing relate to software patents? What about software patents in general? This is a tricky question. We believe software patents should not exist, so that by distributing and using software on a general purpose machine you would not violate any of them. But the inconvenient truth is that they do exist. Software patents are widely available in the USA. Even though they are formally prohibited in the European Union, they indeed are granted by the thousand by the European Patent Office, and also some national patent offices follow the same path. In other countries they are not available. Since patent protection is a national state-granted monopoly, distributing software that violates patents in a given country could be entirely safe if done in another country. Fair use exceptions also exist. So we cannot advise you whether the software we provide would be considered violating patents in your country or in any other country, but that can be said for virtually all kinds of software. Only, since we deal with audio-video standards, and these standards are by and large designed to use certain patented technologies, it is common wisdom that the pieces of software that implement these standards are sensitive in this respect. This is why GStreamer has taken a modular approach, so that you can use a Free plugins or a proprietary, patent royalty bearing, plugin for a given standard. #### What about static vs. dynamic linking and copyleft? We cannot provide one single answer to that question. Since copyright in software works as copyright in literature, static linking means basically that the programmer includes bits of code of the original library in the bytecode at compile time. This amounts to make derivative code of the library without conceivable exceptions, so you need a permission from the copyright holders of the library to do this. A widespread line of thinking says that dynamic linking is conversely not relevant to the copyleft effect, since the mingling of code in a larger work is done at runtime. However, another equally authoritative line of thought says that only certain type of dynamic linking is not copyright relevant. Therefore, using a library that is specifically designed to be loaded into a particular kind of software, even through API, requires permission by the copyright holder of the library when the two pieces are distributed together. In all cases, since most of the software we include in GStreamer is under the LGPL, this permission is granted once for all, subject to compliance with the conditions set out by it. Therefore, the problem only arises when you want to use GPL libraries to make non-GPL applications, and you need to audit your software in that case to make sure that what you do is not an infringement. This is why we have put the GPL libraries in a separate set of optional components, so you have a clearer view of what is safely clear for use, and what might need better investigation on a case-by-case basis. Please be reminded that even for LGPL, the recipient of the software must be in a position to replace the current library with a modified one, and to that effect some conditions apply, among which that for static linking you must also provide the complete toolchain required to relink the library (“any data and utility programs needed for reproducing the executable from it”, except the “major components”) and that the license of the conditions of the resulting program must allow decompilation to debug modifications to the library. ## Licensing applications under the GNU GPL using GStreamer The licensing of GStreamer is no different from a lot of other libraries out there like GTK+ or glibc: we use the [LGPL](http://www.fsf.org/licenses/lgpl.html). What complicates things with regards to GStreamer is its plugin-based design and the heavily patented and proprietary nature of many multimedia codecs. While patents on software are currently only allowed in a small minority of world countries (the US and Australia being the most important of those), the problem is that due to the central place the US hold in the world economy and the computing industry, software patents are hard to ignore wherever you are. Due to this situation, many companies, including major GNU/Linux distributions, get trapped in a situation where they either get bad reviews due to lacking out-of-the-box media playback capabilities (and attempts to educate the reviewers have met with little success so far), or go against their own - and the free software movement's - wish to avoid proprietary software. Due to competitive pressure, most choose to add some support. Doing that through pure free software solutions would have them risk heavy litigation and punishment from patent owners. So when the decision is made to include support for patented codecs, it leaves them the choice of either using special proprietary applications, or try to integrate the support for these codecs through proprietary plugins into the multimedia infrastructure provided by GStreamer. Faced with one of these two evils the GStreamer community of course prefer the second option. The problem which arises is that most free software and open source applications developed use the GPL as their license. While this is generally a good thing, it creates a dilemma for people who want to put together a distribution. The dilemma they face is that if they include proprietary plugins in GStreamer to support patented formats in a way that is legal for them, they do risk running afoul of the GPL license of the applications. We have gotten some conflicting reports from lawyers on whether this is actually a problem, but the official stance of the FSF is that it is a problem. We view the FSF as an authority on this matter, so we are inclined to follow their interpretation of the GPL license. So what does this mean for you as an application developer? Well, it means **you have to make an active decision on whether you want your application to be used together with proprietary plugins or not**. What you decide here will also influence the chances of commercial distributions and Unix vendors shipping your application. The GStreamer community suggest you license your software using a license that will allow non-free, patent implementing or non-GPL compatible plugins to be bundled with GStreamer and your applications, in order to make sure that as many vendors as possible go with GStreamer instead of less free solutions. This in turn we hope and think will let GStreamer be a vehicle for wider use of free formats like the [Xiph.org](http://www.xiph.org/) formats. If you do decide that you want to allow for non-free plugins to be used with your application you have a variety of choices. One of the simplest is using licenses like LGPL, MPL or BSD for your application instead of the GPL. Or you can add a exceptions clause to your GPL license stating that you except GStreamer plugins from the obligations of the GPL. A good example of such a GPL exception clause would be, using the Totem video player project as an example: *The developers of the Totem video player hereby grants permission for non-GPL compatible GStreamer plugins to be used and distributed together with GStreamer and Totem. This permission is above and beyond the permissions granted by the GPL license by which Totem is covered. If you modify this code, you may extend this exception to your version of the code, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.* Our suggestion among these choices is to use the LGPL license, as it is what resembles the GPL most and it makes it a good licensing fit with the major GNU/Linux desktop projects like GNOME and KDE. It also allows you to share code more openly with projects that have compatible licenses. As you might deduce, pure GPL licensed code without the above-mentioned clause is not re-usable in your application under a GPL plus exception clause unless you get the author of the pure GPL code to allow a relicensing to GPL plus exception clause. By choosing the LGPL, there is no need for an exception clause and thus code can be shared freely between your application and other LGPL using projects. We have above outlined the practical reasons for why the GStreamer community suggest you allow non-free plugins to be used with your applications. We feel that in the multimedia arena, the free software community is still not strong enough to set the agenda and that blocking non-free plugins to be used in our infrastructure hurts us more than it hurts the patent owners and their ilk. This view is not shared by everyone. The [Free Software Foundation](http://www.fsf.org) urges you to use an unmodified GPL for your applications, so as to push back against the temptation to use non-free plug-ins. They say that since not everyone else has the strength to reject them because they are unethical, they ask your help to give them a legal reason to do so.