License book club: Artistic License 2.0

Welcome to week two of the license book club! This is a regular thread on WFS where we sit down to read the licenses that we depend on every day, then come back here and discuss them – how do they work, how are they used in practice, what do specific clauses mean, and so on.

This week’s license is the Artistic License 2.0.

:white_check_mark: OSI approved: board minutes
:white_check_mark: FSF approved: GNU comments

The Artistic License is almost exclusively used by the Perl community, used by Perl itself and by most Perl packages on CPAN, the Perl package distribution system.

Artistic 2.0 is a revision to the original Artistic License, which is a classic example of a “boutique” license – one written primarily for vanity rather than with legal rigor. As a consequence, it was cautiously approved by the OSI (even then only with one clause removed), and was never recognized as free software by the FSF on the basis that it was too vague, and “too clever for its own good”. Perl itself was eventually dual licensed with this license and the GPL, and as such was considered free software via the GPL.

An early attempt to fix the problems with Artistic 1.0 came with the Clarified Artistic License, penned by Bradly Kuhn, whose work in the free software community at large is well known. The Clarified license made the minimum set of changes necessary to address the “free” and “open” questions of the original license, but it never caught on.

Later, the Artistic License 2.0 was written from scratch with much greater legal rigor and ultimately became the license of choice for all things Perl.

Read and discuss this license! :open_book:

 (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.

Pretty interesting clause, makes this compliance choice somewhat reciprocal but explicitly making it a requirement towards the Copyright Holder rather than everyone (like you’d approach with “Contributor” in this license and get in most others with Licensee) seems awkward.

 (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.

Different name sounds quite weird, reminds me of Mozilla Firefox® vs. Iceweasel.
At least it looks like Perl itself just asks to bump the patchlevel for packaging[1], perl licensing (which most modules follow by referring to Perl) being Artistic OR GPL-1-or-later anyway.[2]

Update2: Also choice (c) is a pretty interesting one, it basically boils down to same-license or a reciprocal license, I don’t think I’ve seen that in a permissive license before. So the way I understand the 3 choices is either you entirely rename and use any license, or you allow your modifications to be taken back at least by upstream if not all licensees. And I’d guess dual-licensing when modifications aren’t under the Artistic License.

Update1: By the way, here’s its page on OSI Artistic License 2.0 – Open Source Initiative which allows to see the license discussion as well.

  1. perl5/PACKAGING at blead · Perl/perl5 · GitHub ↩︎


1 Like

@ddevault Suggestion for tomorrow: BlueOak-1.0.0


This license always seemed… a bit curious to me. At the same time, I was attracted by it, simply because of “Artistic”. So I guess my vanity got triggered :wink:

I never got to use it for my own projects, even though tempted at times.