Re: Artistic License 2.0
On Wed, Dec 19, 2007 at 09:47:26PM +0200, Allison Randal wrote:
> The Artistic License 2.0 has been approved by the OSI, but not explicitly
> reviewed by debian-legal. Would you like to review it?
The text of the licence is at:
http://www.perlfoundation.org/artistic_license_2_0
Looking at some of the potentially problematic provisions:
> (1) You are permitted to use the Standard Version and create and use
> Modified Versions for any purpose without restriction, provided that
> you do not Distribute the Modified Version.
At first glance that looks non-free, but later provisions in the
licence allow for distribution of the modified version under certain
conditions. So OK so far.
> Distribution of Modified Versions of the Package as Source
> (4) You may Distribute your Modified Version as Source (either
> gratis or for a Distributor Fee, and with or without a Compiled form
> of the Modified Version) provided that you clearly document how it
> differs from the Standard Version, including, but not limited to,
> documenting any non-standard features, executables, or modules, and
> provided that you do at least ONE of the following:
The crucial words being "AT LEAST one" - i.e. it doesn't matter if
some of the options are "non-free" so long as "free" options are
available.
>
> (a) make the Modified Version available to the Copyright Holder of
> the Standard Version, under the Original License, so that the
> Copyright Holder may include your modifications in the Standard
> Version.
In itself that seems to be non-free, if it is requiring the supplying
of modifications back upstream. But other options are available.
> (b) ensure that installation of your Modified Version does not
> prevent the user installing or running the Standard Version. In
> addition, the Modified Version must bear a name that is different
> from the name of the Standard Version.
That seems OK too in principle.
> (c) allow anyone who receives a copy of the Modified Version to make
> the Source form of the Modified Version available to others under
>
> (i) the Original License or
>
> (ii) a license that permits the licensee to freely copy, modify and
> redistribute the Modified Version using the same licensing terms
> that apply to the copy that the licensee received, and requires that
> the Source form of the Modified Version, and of any works derived
> from it, be made freely available in that license fees are
> prohibited but Distributor Fees are allowed.
The "license fees" versus "distribution fees" distinction is also
found in GPL v3, and is implicit in v2, so that's OK. It should also
be noted that, in the FSF's view, 4(c) of the Artistic Licence 2.0
makes the licence GPL-compatible.
Similar observations apply to the rest of the licence. It seems to
follow an unfortunate trend towards increased complexity in free
software licences, but that's a different matter. I notice that the
FSF regards this as a free, GPL-compatible licence, and I can't see
any reason for rejecting it on DFSG grounds.
Out of interest, is there any reason why the developers of Parrot have
adopted this licence rather than the GPL, given that the code (with
trivial modifications) can be relicensed under the GPL anyway?
John
(TINLA)
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