GNU LESSER GENERAL PUBLIC LICENSE Version 2.1, February 1999
Copyright © 1991, 1999 Free Software Foundation, Inc.
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not
allowed.
[This is the first released version of the Lesser GPL. It also counts as the successor of the GNU Library Public
License, version 2, hence the version number 2.1.]
The licenses for most software are designed to take away your freedom to share and change it. By contrast,
the GNU General Public Licenses are intended to guarantee your freedom to share and change free software
– to make sure the software is free for all its users.
This License, the Lesser General Public License, applies to some specially designated software packages
– typically libraries – of the Free Software Foundation and other authors who decide to use it. You can use
it too, but we suggest you first think carefully about whether this license or the ordinary General Public
License is the better strategy to use in any particular case, based on the explanations below.
When we speak of free software, we are referring to freedom of use, not price. Our General Public
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change the software or use pieces of it in new free programs; and that you are informed that you can do
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To protect your rights, we need to make restrictions that forbid distributors to deny you these rights or
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For example, if you distribute copies of the library, whether gratis or for a fee, you must give the
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We protect your rights with a two step method: (1) we copyright the library, and (2) we offer you this
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To protect each distributor, we want to make it very clear that there is no warranty for the free library.
Also, if the library is modified by someone else and passed on, the recipients should know that what they
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Finally, software patents pose a constant threat to the existence of any free program. We wish to make
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Most GNU software, including some libraries, is covered by the ordinary GNU General Public License.
This license, the GNU Lesser General Public License, applies to certain designated libraries, and is quite
different from the ordinary General Public License. We use this license for certain libraries in order to permit
linking those libraries into non-free programs.
Exhibit B
Preamble