Re: LGPL module linked with a GPL lib

[Michael Poole <mdpoole@troilus.org>]

Jeff Licquia writes:

> On Tue, 2005-07-26 at 11:14 -0300, Humberto Massa Guimarães wrote:
>> I find this discussion ultimately absurd. Debian is *not*
>> distributing a derivative work. Debian does *not* distribute a work
>> that includes both plugins/libraries. The fact that the things are
>> (dynamically) linked at run time, especially combined with the fact
>> that the plugins are opened with dlopen() and use stable API, is
>> *more* than enough to lift any (inexistent IMHO) "no-link"
>> requirement of the GPL.
>
> I find most of this response confusing.
>
> First of all, it's clear that Debian *is* distributing a derived work
> based on GPLed libraries, called "Debian GNU/Linux".  The specific case
> in question may fall under the "mere aggregation" clause of the GPL, but
> then this is the point you should argue.

US copyright law distinguishes between the classes of work called
"derivative works" and "compilations".  The usual reading is that a
"compilation" or "collective work" (which is a subset of
"compilation") is what the GPL means by "mere aggregation", and a
"derivative work" is covered by the stricter terms.  The Berne
Convention makes a similar distinction of a "collection" versus the
works that comprise the collection.

A compilation or collective work under US law is not necessarily a
derivative work of any of its components.  The GPL's use of
"derivative" and "derived" is fuzzy in this sense, which is one reason
the terms from copyright law are used more often than the GPL's terms.

Michael Poole