Subject: Re: EROS license
From: Ian Lance Taylor <>
Date: 27 Jun 1999 22:20:24 -0400

   From: Russell Nelson <>
   Date: Sun, 27 Jun 1999 19:50:24 -0400 (EDT)

   My understanding does not match your re-statement of it.  The author
   of a GPL-licensed project has the option of licensing the code under
   another license.  That doesn't change the status of the GPL-licensed
   version.  To "take the project proprietary" is not possible under US
   Copyright law, and the whole Berne Convention for all I know.  Copy
   rights cannot be retracted once granted.

When I see the phrase ``take the project proprietary'' I interpret as
meaning something akin to what, for example, DEC did to the X11
sources.  DEC Ultrix machines shipped with X binaries without source,
and the DEC patches were required in order to build usable sources,
but were not available.

I never assume that the phrase means anything like ``track down and
destroy all existing copies of the sources'' or ``make it illegal to
distribute the existing sources.''  That seems clearly impossible.

Evidently, though, you felt the need to point out the impossibility of
the second scenario.  Can you recommend some other short phrase we can
use to describe the first scenario I outlined in order to avoid this
sort of confusion?

   Some authors request back-licensing for the purposes of
   dual-licensing.  Others use a GPL-like license which requires it.
   This is what Ian is objecting to.

I don't quite understand what you are saying here, so my next
paragraph may completely miss the point.

I hope it's clear that I am not objecting to the GPL.  I also hope
it's clear that the GPL itself does not require any sort of licensing
arrangement with a contributor; the FSF does insist upon such an
arrangement, but the Linux kernel project, for example, does not.

It's certainly true, as you and Stephen Turnbull have pointed out,
that the author of a GPL project may take advantage of retaining the
copyright and release a proprietary version of the code.  If that
happened to a project to which I had contributed, and if I were not
warned of the possibility beforehand, I believe I would feel that I
had been misled and betrayed.