Can I use an LGPLv3 library in my WordPress plugin

Question

I want to publish a plugin on WordPress. My plugin uses a library which is licensed under the LGPLv3.

I am planning to ship the library along with plugin code, however, the library isn't statically linked to the rest of the code.

WordPress states,

Anything stored in the plugin directory hosted on WordPress.org — must comply with the GPL or a GPL-Compatible license. Included third-party libraries, code, images, or otherwise, must be compatible

By using this library, does my plugin comply with either the GPL or GPL-Compatible Licence?

Answer 1

Wordpress plugins must be available under the same license as Wordpress: GPLv2 or later. That in turn means any software that you use in the plugin must use a compatible license.

The LGPL is a highly compatible variant of the GPL. To determine exact compatibility we can look at the compatibility matrix in the GPL FAQ. For the combination “I want to use a library under LGPLv3” and “I want to license my code under GPLv2 or later”, the entry says:

OK: Combination is under GPLv3

Because GPLv2 does not permit combinations with LGPLv3, you must convey the project under GPLv3's terms in this case, since it will allow that combination.

So yes, using that library is fine, and you can license your plugin under GPLv3.