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---
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title: GNU Lesser General Public License v2.1
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spdx-id: LGPL-2.1
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nickname: GNU LGPLv2.1
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redirect_from: /licenses/lgpl-v2.1/
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source: https://www.gnu.org/licenses/lgpl-2.1.txt
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hidden: false
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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.
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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.
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using:
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permissions:
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- commercial-use
- modifications
- distribution
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- private-use
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conditions:
- include-copyright
- disclose-source
- document-changes
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- same-license--library
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limitations:
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- liability
- warranty
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---
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GNU LESSER GENERAL PUBLIC LICENSE
Version 2.1, February 1999
Copyright (C) 1991, 1999 Free Software Foundation, Inc.
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51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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Everyone is permitted to copy and distribute verbatim copies of this license
document, but changing it is not allowed.
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[This is the first released version of the Lesser GPL. It also counts as the
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successor of the GNU Library Public License, version 2, hence the version
number 2.1.]
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Preamble
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The licenses for most software are designed to take away your freedom to share
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END OF TERMS AND CONDITIONS
How to Apply These Terms to Your New Libraries
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If you develop a new library, and you want it to be of the greatest possible
use to the public, we recommend making it free software that everyone can
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To apply these terms, attach the following notices to the library. It is
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one line to give the library's name and an idea of what it does.
Copyright (C) year name of author
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This library is free software; you can redistribute it and/or modify it
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your option) any later version.
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This library is distributed in the hope that it will be useful, but
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General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA Also
add information on how to contact you by electronic and paper mail.
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You should also get your employer (if you work as a programmer) or your
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necessary. Here is a sample; alter the names:
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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
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That's all there is to it!
