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---
title: GNU Lesser General Public License v2.1
spdx-id: LGPL-2.1
nickname: GNU LGPLv2.1
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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.

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using:

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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
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   NO WARRANTY

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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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< one line to give the library's name and an idea of what it does. >

Copyright (C) < year > < name of author >

This library is free software; you can redistribute it and/or modify it under
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any later version.

This library is distributed in the hope that it will be useful, but WITHOUT
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You should have received a copy of the GNU Lesser General Public License along
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Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA Also add information
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You should also get your employer (if you work as a programmer) or your
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is a sample; alter the names:

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!