Most of the software packages you have listed are indeed open-source
products that permit users to modify and sell them. I shall enumerate
the packages in the order you gave them and describe the license under
which each one is published.
The official OpenOffice website states that its software is made available
under the GNU Project's Lesser General Public License.
OpenOffice.org uses a single open-source license for the source
code and a separate documentation license for most documents
published on the website without the intention of being included
in the product. The source-code license is the GNU Lesser General
The full text of this license, which is called the LGPL for short, can
be read on the following page. I shall quote its most important sections.
0. This License Agreement applies to any software library or other
program which contains a notice placed by the copyright holder
or other authorized party saying it may be distributed under
the terms of this Lesser General Public License (also called
"this License"). [...]
1. You may copy and distribute verbatim copies of the Library's
complete source code as you receive it, in any medium, provided
that you conspicuously and appropriately publish on each copy an
appropriate copyright notice and disclaimer of warranty; keep
intact all the notices that refer to this License and to the
absence of any warranty; and distribute a copy of this License
along with the Library.
You may charge a fee for the physical act of transferring a copy,
and you may at your option offer warranty protection in exchange
for a fee.
2. You may modify your copy or copies of the Library or any
portion of it, thus forming a work based on the Library, and
copy and distribute such modifications or work under the terms
of Section 1 above, provided that you also meet all of these
a) The modified work must itself be a software library.
b) You must cause the files modified to carry prominent
notices stating that you changed the files and the date
of any change.
c) You must cause the whole of the work to be licensed
at no charge to all third parties under the terms of
GNU Project: GNU Lesser General Public License: Terms and Conditions
for Copying, Distribution and Modification
In essence, then, you are permitted to modify and sell the software
as long as you distribute your derived product with the same license,
namely the LGPL, and you include documentation of changes you have
made to the original software. There is no need for you to acquire any
additional rights or to establish a contract with the authors in order
to modify and sell their software, since the license under which they
publish the software explicitly gives everyone the right to modification
The major restriction this imposes on your commercial efforts is that
your derived product must also be published under the LGPL, which means
that you cannot legally prevent anyone from modifying and selling your own
version of it. There is no way around this restriction. The very purpose
of the LGPL is to ensure freedom of the software and all its derivatives.
Furthermore, the LGPL requires that you make available the source code
of your derived product. It is not necessary to include the source code
with the product itself, but you must at least include a written notice
telling users how they can freely obtain the source code. Don't forget
that you must, at the same time, clearly advertise the fact that your
product is being released under the LGPL. This is made clear in the
preamble of the LGPL.
For example, if you distribute copies of the library, whether
gratis or for a fee, you must give the recipients all the rights
that we gave you. You must make sure that they, too, receive or
can get the source code. If you link other code with the library,
you must provide complete object files to the recipients, so
that they can relink them with the library after making changes
to the library and recompiling it. And you must show them these
terms so they know their rights.
GNU Project: GNU Lesser General Public License: Preamble
b) ClamWin, ClamMail
ClamWin's home page states the following.
ClamWin Free Antivirus uses the GNU General Public License by
the Free Software Foundation and is free (as in freedom) software.
This software package is released under the GPL, which is a stronger
version of the LGPL. The preamble of the LGPL summarizes the difference
Although the Lesser General Public License is Less protective of
the users' freedom, it does ensure that the user of a program that
is linked with the Library has the freedom and the wherewithal
to run that program using a modified version of the Library.
The precise terms and conditions for copying, distribution
and modification follow. Pay close attention to the difference
between a "work based on the library" and a "work that uses the
library". The former contains code derived from the library,
whereas the latter must be combined with the library in order
GNU Project: GNU Lesser General Public License: Preamble
What you are proposing to do is not to write code that links to a software
package, but to modify the software package itself and sell it. Therefore,
there is no difference in your case between the conditions imposed by the
LGPL and the GPL. Both licenses make the same requirements of software
publishers who wish to modify and sell a package that has been released
under the license.
Again, there is no need to acquire further rights or to establish
a further contract. You are simply required to release your derived
product under the same license, inform users that it is released under
the license, and make the source code of the derived product freely
available to anyone who wants it.
The GNU Project's FAQ on the GPL addresses the subject of selling software
under this license.
Does the GPL allow me to sell copies of the program for money?
Yes, the GPL allows everyone to do this. The right to sell
copies is part of the definition of free software. Except
in one special situation, there is no limit on what
price you can charge. (The one exception is the required
written offer to provide source code that must accompany
Does the GPL allow me to charge a fee for downloading the program
from my site?
Yes. You can charge any fee you wish for distributing
a copy of the program. If you distribute binaries by
download, you must provide "equivalent access" to download
the source--therefore, the fee to download source may
not be greater than the fee to download the binary.
Does the GPL allow me to require that anyone who receives the
software must pay me a fee and/or notify me?
No. In fact, a requirement like that would make the
program non-free. If people have to pay when they get
a copy of a program, or if they have to notify anyone
in particular, then the program is not free. See the
definition of free software.
The GPL is a free software license, and therefore it
permits people to use and even redistribute the software
without being required to pay anyone a fee for doing so.
If I distribute GPL'd software for a fee, am I required to also
make it available to the public without a charge?
No. However, if someone pays your fee and gets a copy, the
GPL gives them the freedom to release it to the public,
with or without a fee. For example, someone could pay
your fee, and then put her copy on a web site for the
GNU Project: Frequently Asked Questions about the GNU GPL: Does the GPL
allow me to sell copies of the program for money?
GNU Project: Frequently Asked Questions about the GNU GPLQ
There is also a separate page devoted to the philosophy of selling
Actually we encourage people who redistribute free software to
charge as much as they wish or can.
Except for one special situation, the GNU General Public License
(20k characters) (GNU GPL) has no requirements about how much
you can charge for distributing a copy of free software. You can
charge nothing, a penny, a dollar, or a billion dollars. It's up
to you, and the marketplace, so don't complain to us if nobody
wants to pay a billion dollars for a copy.
GNU Project: Philosophy: Selling Free Software
ClamMail, although it is authored independently from ClamWin, is also
released under the GPL. Therefore, exactly the same conditions apply if
you wish to modify and sell it: you must preserve the license, notify
users of the license, and make the source code freely available.
Features: [...] Licensed under GNU General Public License
BranSoft: ClamMail: Features
Winpooch is also released under the GPL, so you can modify and sell it
under the conditions I have outlined above.
License: GNU General Public License (GPL)
d) CCleaner, Eraser
CCleaner is not, in fact, an open-source software package. It is freeware,
which is not the same thing.
CCleaner is a freeware software optimization and privacy
application for Microsoft Windows.
The similarity between freeware and open source is that both types of
software may be freely downloaded by users. However, freeware does not
necessarily allow for modification and redistribution.
The only criterion for being classified as "freeware" is
that the software must be made available at no cost. The
software license may impose other restrictions that limit the
user's freedom. Freeware and "free software" are not the same
thing. The former rules out payment for transmission of a copy,
while the latter explicitly grants the freedom to sell copies
of the software. The GPL v 2.0 states, "You may charge a fee
for the physical act of transferring a copy," and stipulates
that you are not allowed to withdraw this right from anyone who
receives a copy: "you must give the recipients all the rights
that you have". However, "free software" is often confused with
freeware. "Free software" is a term often used in reference to
software released under the GPL or other open source licenses
promoted by the Free Software Foundation (FSF).
Wikipedia: Freeware: Freeware licensing
Hence, you do not have permission to modify and sell CCleaner, nor is
there any set procedure for acquiring this permission. You will have
to contact the authors if you wish to negotiate some kind of commercial
agreement with them.
Eraser, on the other hand, is indeed an open-source product. The GPL
permits you to modify and resell it without acquiring further rights.
Q: "Can I use Eraser source code in my own programs?"
A: The source code can be used, modified and redistributed
under the terms of the GNU General Public License (included
with the code). Basically, you may use Eraser source code in
your own programs as long as you release your source under the
same license. I would also appreciate a note if you use the code.
Sami Tolvanen: Eraser: FAQ
The full source code for Eraser 5.7 is released under GNU General
Heidi Computers: Eraser: Source
e) GIMP, Inkscape, Dia, Blender
GIMP, Inkscape, Dia, and Blender are all released under the GPL. You are
free to modify and sell them as long as you comply with the requirements
of the license, which I have previously explained. You may also be
interested in the GIMP website's page of "Recommendations for those who
sell copies of the GIMP," excerpted below.
I it legal to sell copies of the GIMP?
Yes. The terms and conditions for copying, distribution and
modification of the GIMP are clearly listed in the GNU General
Public License. Redistribution for free or for profit is
specifically allowed, as long as the license is included and
the source code is made available.
Recommendations for those who sell copies of the GIMP
If you or your company intend to sell the GIMP, it would be nice
to follow these guidelines:
1. Be honest. Do not try to hide the fact that the product
that you are selling is or contains the GIMP. Mention it in
2. Add value. Try to provide more than what can be found in
the default GIMP package. Include a nice installer, additional
plug-ins, some nice artwork, some custom brushes and textures,
your own tutorials and documentation, printed copies of the
documentation, etc. There are many ways to add value to the GIMP
and to make your customers happy.
3. Respect the GPL. The GPL requires you to make the source code
available. The best solution is to include the source code on the
same medium as the GIMP installation package, but you can also
include a written offer to supply the source code on request.
Note that you cannot simply give a link to the GIMP ftp mirrors:
it should be the exact source code that was used to compile the
binary package that you are selling and you have to cover the
costs of redistribution yourself. If you sell and distribute the
binaries online, the GPL requires you to make the source code
available "from the same place" so giving a link to the GIMP
mirrors is not sufficient (see also this section of the GPL FAQ).
4. Support your users. If the version of the GIMP that you
are selling is modified in any way, you should inform your
users and try to handle the support requests related to that
version. Providing good support is another way to make your
Finally, think about giving something back. If the software
created by many volunteers helps your business, it would be nice
to return the favor by helping the developers. You can contribute
by sending some improvements to the code or by sponsoring
some events such as the GIMP developer's conference. This is
not required, but happy developers are more likely to create a
better product that you can sell later...
GIMP: Selling the GIMP
Dia is a gtk+ based diagram creation program released under the
Dia: a drawing program
Blender is being released with source codes under the GNU General
Blender therefore is fully free to use and distribute within
any educational, professional or commercial environment.
7-Zip is released under the Lesser GPL, or LGPL, just like OpenOffice. As
I explained earlier, the provisions of the LGPL are the same as those of
the GPL if you wish to sell a copy or a modified version of the licensed
software. Thus, you are free to modify and sell 7-Zip if and only if your
derived product is also under the LGPL (or GPL), you advertise this fact
in your distribution, and you make the source code freely available.
7-Zip is free software distributed under the GNU LGPL.
Amanda is open-source software that comes with its own license, which
I quote below.
Permission to use, copy, modify, distribute, and sell this
software and its documentation for any purpose is hereby
granted without fee, provided that the above copyright notice
appear in all copies and that both that copyright notice and
this permission notice appear in supporting documentation, and
that the name of U.M. not be used in advertising or publicity
pertaining to distribution of the software without specific,
written prior permission.
Thus, you may modify and sell Amanda without securing further rights or
establishing a further contract as long as your derived product retains
the copyright notice. In effect, you are bound by the same restrictions
as the GPL, since you cannot prevent anyone from modifying and reselling
the product you have derived from Amanda. In addition, the copyright
notice stipulates that you may not refer to the University of Maryland,
where Amanda was developed, in your marketing materials.
I have enjoyed answering your question. If you have any concerns about
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open source license
modify resell open source
gpl modify sell
lgpl difference gpl
freeware difference open source