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---
title: GNU Lesser General Public License v2.1
spdx-id: LGPL-2.1
nickname: GNU LGPLv2.1
redirect_from: /licenses/lgpl-v2.1/
source: https://www.gnu.org/licenses/lgpl-2.1.txt
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description: Primarily used for software libraries, the GNU LGPL requires that derived works be licensed under the same license, but works that only link to it do not fall under this restriction. There are two commonly used versions of the GNU LGPL.
how: Create a text file (typically named LICENSE or LICENSE.txt) in the root of your source code and copy the text of the license into the file.
note: The Free Software Foundation recommends taking the additional step of adding a boilerplate notice to the top of each file. The boilerplate can be found at the end of the license.
using:
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conditions:
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limitations:
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---
GNU LESSER GENERAL PUBLIC LICENSE
Version 2.1, February 1999
Copyright (C) 1991, 1999 Free Software Foundation, Inc.
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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.]
Preamble
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
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This license, the Lesser General Public License, applies to some specially
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suggest you first think carefully about whether this license or the ordinary
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END OF TERMS AND CONDITIONS
How to Apply These Terms to Your New Libraries
If you develop a new library, and you want it to be of the greatest possible
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Copyright (C) year name of author
This library is free software; you can redistribute it and/or modify it
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This library is distributed in the hope that it will be useful, but
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Yoyodyne, Inc., hereby disclaims all copyright interest in
the library `Frob' (a library for tweaking knobs) written
by James Random Hacker.
signature of Ty Coon, 1 April 1990
Ty Coon, President of Vice
That's all there is to it!