LGPL 2.1 + GPL 3 = problems?

[Matthew Flaschen]

Philippe Verdy wrote:
> If your copyright notice that references the appropriate licence to use only
> specifies a precise version of the licence, you can still use a higher
> version according to the terms of this referenced original licence.

This is only relevant to the LGPL2.1 clause allowing use of later 
versions of the GPL.  The main GPL does not allow use of later versions

  However,
> if you really want to exclude any higher version, your copyright notice
> should explicitly contain an "additional restriction" (as defined and
> allowed in the GPL licences), such as:
> 
> 	<one line for the name of the program and describing what it does>
> 	Copyright (C) <year> <author name>
> 	This library is a free software; you may redistribute it or modify
> it
> 	according to the terms of the "GNU Lesser General Public License"
> 	version 2.1 as published by the Free Software Foundation, with the
> 	additional restriction that any later versions are excluded.

It should say later versions of GPL.

> Without this EXPLICIT additional restriction in your copyright notice, the
> original terms of the GPL v2.1 license allows upgrading the version of the

The original terms of LGPLv2.1 you mean.

> referenced license. Almost all GPL- or LGPL-licensed works do not have such
> explicit "additional restriction", and can then be used or conveyed under
> the terms of a newer version.

No.  No GPL work can be used under a new version of the license unless 
the license notice allows it.

> Reread for example the section 4 of the GPLv3 which explicitly states that
> authors can decide which version of the GPL they accept.

It says no such thing.  License is defined as "“This License” refers to 
version 3 of the GNU General Public License." which doesn't allow later 
versions (unless otherwise allowed in the license notice).

> The "or any later version" is an explicit statement that is now highly recommended, but this
> is not the only option. GPLv3 allows later versions to be acceptable only
> through acceptation by a given proxy. And it also allows an author to
> enumerate the accepted version numbers.

None of these really require a clause in the license.

> These are viewed as additional permissions or restrictions

They're additional permissions, because they can be removed (for 
instance you can convert "GPLv3 or later" to "GPLv3")

, according to
> section 7, which also allows changing the terms for the limitation of
> warranty, or allows requiring or prohibiting the preservation of the
> original author names, or 

> limiting the usage of their personal names within commercial products:

It certainly doesn't limit this to commercial products (that would be an 
OSD 6 violation).  It says, "Limiting the use for publicity purposes of 
names of licensors or authors of the material".  I don't see what this 
has to do with choosing later versions of (L)GPL, though.

Matthew Flaschen