Subject: Re: Viral licenses (was: wxWindows library...)
From: John Cowan <>
Date: Sun, 14 Dec 2003 19:12:19 -0500

Alexander Terekhov scripsit:

> Arnoud Engelfriet wrote:
> [...]
> > If you distribute a work that is a derivative of GPL-licensed
> > code, and you do not comply with the GPL, you simply violate
> > the license. ...
> Yeah. Simple.

What Arnoud said is both simple and correct.  The definition of
"derivative work" is not.

> The Lesser GPL, or LGPL, is a second software license written 
> by the Free Software Foundation. It sheds some light on the 
> FSF's view of linking and derivative works, both for the GPL 
> and LGPL: 
>   When a program is linked with a library, whether 
>   statically or using a shared library [i.e., dynamically], 
>   the combination of the two is legally speaking a combined 
>   work, a derivative of the original library. The ordinary 
>   General Public License therefore permits such linking only 
>   if the entire combination fits its criteria of freedom. The 
>   Lesser General Public License permits more lax criteria for 
>   linking other code with the library. 

This quotation from the LGPL comes from its Preamble, which does
not seem to me (IANAL) to be part of the legally binding bits.

In any event, it doesn't matter what Stallman thinks is a derivative
work, or what Torvalds thinks, or what Moglen thinks.  "Derivative work",
in the U.S. at least, is not a bright-line term, and the only thing
that's going to matter is what a judge, or succession of judges, think
it means.  TINLA.

> In other words, dynamic linking is permissible under the LGPL, 
> but not under the GPL. 

In the FSF's view, static linking is equally permissible under the LGPL.
This whole static/dynamic distinction is a red herring.

> So basically in the "FSF world", your car is a derivative 
> work of its gas pedal. Give me a break.

You can't compare property in physical things directly to its
copyright.  If you replace the car by a detailed description of it (#1),
and incorporate into that a detailed description of the gas pedal (#2)
that has already been written, then #1 is indeed a derivative work
of #2.

Overhead, without any fuss, the stars were going out.
        --Arthur C. Clarke, "The Nine Billion Names of God"
                John Cowan <>
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