T H E C O I N L I C E N S I N G F A Q
-1 . S w i t c h t o B S D
Coin is now licensed under the 3-clause BSD license (see
COPYING). The remaining contents of this file is mostly
interesting for historical reasons.
0 . G e n e r a l q u e s t i o n s
Q 0.0: Coin is under the GNU General Public License ("GPL").
Can I use it in my proprietary, commercially sold application?
A: No, the GNU GPL restricts the applications that can use Coin to
have to be Free Software, and otherwise compatible with the GNU
The distribution and availability of the Coin library under the
GNU GPL is primarily meant to be a service for those who write
other Free Software libraries or applications. If you write
proprietary software and would like to use the Coin library, see
the next question.
Q 0.1: Is it possible to use the Coin library without the restrictions
of the GNU GPL?
A: Yes, as a service for those who would like to use the Coin library
in proprietary software, we at Kongsberg Oil & Gas Technologies offer
the "Coin Professional Edition License" which buys developers that are
license holders the option to use the library with no strings
attached. The "Coin Professional Edition License" covers all the
Coin libraries, unless otherwise specified.
By "no strings attached", we of course mean that you as a
software developer would not have to obey the restrictions of
the GNU GPL, as you would use the Coin library under our
"Professional Edition" license instead.
The Coin Professional Edition License additionally covers
other libraries in the "Coin family" for no extra cost,
including all the GUI toolkits (SoQt, SoWin, SoGtk, SoXt,
Sc21) and Kongsberg Oil & Gas Technologies's 3D file format libraries
Dime and Profit.
See <URL:http://www.coin3d.org> for more information about the
details of these libraries.
Prioritized support services is also part of the package -- your
support requests will be sent straight to the top of the
todo-stack of our developers. The developers used as first-tier
support for our Coin Professional Edition License holders are
the same people who have written all the sourcecode of the
library in the first place, so you will be in very good hands.
We take pride in giving our customers excellent support, and
since the Coin libraries are what our developers love to work with,
it's given with a smile. :-)
Oh, and one additional benefit from being a Coin Professional
Edition License holder: you are allowed to cut'n'paste from our
sourcecode and use it in your own applications without having to
worry about licensing issues. This is for instance very
convenient when writing extension components for Coin, like new
nodes or action types.
You may also cut'n'paste code from all our example programs in
the same manner (these are also originally under the GNU GPL, by
Q 0.2: How can you sell a "Professional Edition License" when the
library is released under the GNU GPL? Wouldn't that be
disallowed by the GNU GPL?
A: Kongsberg Oil & Gas Technologies can do this dual licensing "trick"
with Coin because we are full copyright holders -- ie we own every
single line of code written for the Coin library. Therefore we are
able to license the Coin library both as Free Software aswell as
under a special purpose license for proprietary software
vendors. (If you are familiar with TrollTech's "Qt" library,
they use the same strategy.)
Q 0.3: What happens if I don't renew my Coin PEL? Can I still continue
A: Yes. You can continue development using the last version of
Coin (or any earlier version, if you want) that was released
while you were a registered PEL holder. Version in this context
means "release with a unique version number", so for instance
1.0.0 and 1.0.1 count as different versions.
Of course you are not allowed to use any version of Coin that
was released after the expiry date, and you will not get any
more developer support.
Q 0.4: Can't I just use the Coin Free Edition to develop my software
in-house, and then get a PEL and switch to a non-Free license
just before I release it?
A: From a strictly legal point of view, this is possible. As
long as you do not release binaries, you do not need to
release the source code either, so you can work on a piece of
software under the terms of the GPL, and then re-license it
before releasing it.
We strongly discourage this approach, though, for several
reasons. First, the Free Edition of Coin is intended for Free
Software developers, and using it for proprietary development
obviously is against this intention.
Second, the PEL is meant to be a per-developer license, taking
into account that you are likely to need professional support
when doing your development. By getting a PEL when you start
developing your software, you can benefit from our priority
support when you actually need it - during development.
Third, note that even if you never release the in-house GPL
version to the public, the terms of the GPL are valid for all
the people involved in the project. That means that everybody
with access to the software has the irrevokable right to get
the source code and distribute it to whomever they want,
including posting it on public websites etc. - and this would
be perfectly legal. This is the freedom granted by the GPL,
and it intentionally clashes with proprietary development.
I . C o n c e r n i n g t h e n e w P E L ( v 2 )
Q 1.0: I am a Coin PEL holder. What does the new Coin PEL (v2) change for
A: Nothing. The new Coin PEL is merely a more detailed specification
of the currently valid rights and conditions.
Q 1.1: So then why did you bother making a new one?
A: In the previous license, many points were either not covered at
all, or not in enough detail. The many questions that we
received concerning the actual rights and restrictions showed
us the importance of clearly stating these things, and the
Coin-2 release was a good opportunity to put the new license
Q 1.2: So, how about a summary in English instead of Legalese?
A: My pleasure - here you go. Paragraph by paragraph (note: everything
that is said about Coin below also applies to the So*
libraries and Dime/Profit):
After the definition of what the license is about, and whom it
concerns, it is stated that SIM is and remains the copyright
holder and owner of Coin - the license gives you the right to
use the software, we do not sell it to you.
You are getting a license for one individual - you, or
somebody in your company. We are deliberately not restrictive
about this "in your company", so it's perfectly okay to
acquire a company license and have an external consultant be
the actual Coin developer. The important part is the idea that
it is a personal developer license, not a "site license" or a
company-wide license. So one license is needed for each
developer working on Coin-related development.
The license is valid for one year, after which you will get a
renewal offer from us.
You are allowed to use Coin to develop your product, whatever
that is - except if you are developing a directly competing product.
You can ship binary version of Coin - modified or unmodified -
with your product. You are also allowed to distribute the
source code, but only in unmodified form. If you have changed
anything, you must distribute the original source code plus
patches. (See also next question.)
You will get one year of free upgrades, and you are entitled
to developer support for that period.
Now if you don't extend your license after one year, you can
of course still ship your product. You are also allowed to
continue doing development using the last version of Coin that
was released while you had a valid license. You will not get
any more updates, and you will not get any more support.
The rest is off-the-shelf legal provisions - standard clauses
in the (unexpected) case of a lawsuit, statement that we don't
take any warranty (you are responsible for e.g. loss of data)
Q 1.3: I am allowed to modify the Coin library itself?!
A: Yup. You are allowed to do that, for instance in order to fix bugs
or adapt it to your special needs. You are of course not
allowed to make a modified version of Coin and sell it as your
own product. Note that if you have made modifications to the
Coin library, you are not allowed to distribute the modified
source code - you have to use source code diffs (patches). You
are free to distribute a binary of the changed version without
the need to disclose your source code, but then you can't name
that binary "Coin". This is necessary to avoid conflicts and
Q 1.4: If I distribute the Coin source code, under what license is it for
A: Under the GPL and PEL. The license is connected to
copyrightable material (in our case, the Coin source code),
not the modus of distribution. So regardless of how you get
the source - from SIM, from somebody else's website, from a
Debian CD, from Santa Claus - it will always be under both the
GPL and the PEL. That means that your customers can use the
Coin source for Free Software development as covered by the
GPL. For any proprietary development, they must acquire a PEL.
I I . C o n c e r n i n g t h e F r e e E d i t i o n -
t h e s w i t c h f r o m L G P L t o G P L
Q 2.0: I am a Coin PEL holder. What does the change from LGPL to GPL
mean for me?
A: Nothing at all. Your rights as PEL user are not in any way
affected by the LGPL or GPL version of Coin.
Q 2.1: I was using Coin under the LGPL. What does the change from
LGPL to GPL mean for me?
A: Both the GPL and the LGPL are Free Software licenses. The
main difference is that, given that one fulfills a set of
restrictions on how the executable is distributed, the LGPL
permits the use of the library in proprietary programs, while
the GPL does not allow that under any circumstances.
In the concrete case of Coin, this comes down to:
If you write a Free Software application, licensed under the
GPL or another compatible Free Software license, you are
allowed to link against Coin. If you write a proprietary
application, you are not allowed to use Coin under the GPL -
you have to acquire a PEL.
Q 2.2: Why are you switching from LGPL to GPL?
A: There two main reasons why we are switching from LGPL to GPL.
First of all, we strongly believe in Free Software. The idea
behind the Free Edition is not to give away Coin - we want to
share our work with the Free Software community, to the
benefit of those who want to share /their/ software with the
community. So if you want to develop Free Software, that's
great, and for that purpose, you are welcome and encouraged to
use Coin. If you do not develop Free Software, the Free
Edition simply does not apply to you; that's what the Coin
Professional Edition is for.
Secondly, using the GPL instead of the LGPL fits better with
our business model. Development costs money :) so of course we
don't want people to develop products (non-Free Software, that
is) based on Coin without contributing anything to the Coin
development and maintenance costs.
PEL | http://www.coin3d.org/licensing/coin3d/Coin-PEL.txt
GPL | http://www.fsf.org/licenses/gpl.txt
LGPL | http://www.fsf.org/licenses/lgpl.txt