Subject: Re: Understanding the LGPL.
From: John Cowan <>
Date: Thu, 2 Oct 2003 22:04:20 -0400

Daniel Carrera scripsit:

> In practical terms, how is the LGPL license different from the BSD?
> If they both permit a third-party to use my work for propietary purposes, 
> is there any greater "protection" that is afforded by the LGPL over the 
> BSD?

In practical terms, the LGPL is applied to libraries, and works like the
GPL as far as changes to the library is concerned, but the library can
be linked to non-GPLed code provided it's possible for the end user to
replace the library with an updated version.  (I suspect this proviso
is often ignored in proprietary apps.)

It's a very complex license, because it attempts to draw the line between
"a work based on the library" and "a work that uses the library", which
is not at all easy to draw.

Anything licensed under the LGPL is effectively dual-licensed under the
GPL as well.

The license of Guile, which is the GPL plus a proviso saying "you can 
link this with anything you want", often does the work of the LGPL
more simply.

John Cowan
Dievas dave dantis; Dievas duos duonos          --Lithuanian proverb
Deus dedit dentes; deus dabit panem             --Latin version thereof
Deity donated dentition;
  deity'll donate doughnuts                     --English version by Muke Tever
God gave gums; God'll give granary              --Version by Mat McVeagh
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