[[!meta title="Results of the scary licence questions…"]]
[[!meta author="Daniel Silverstone"]]
[[!meta date="2008-07-27 12:13:55 +0100"]]
[[!tag converted-badly-from-textile tech]]
I’m sorry that this has taken so long to post, but here is, at last, the
promised summary of the answers I received in response to [my
about licences. If any of my attribution links are wrong, then please do
email me so that I can fix them. I have summarised people’s responses
unless they were short, however I am using people’s names; if you wished
to remain anonymous then I’m sorry, and if you email me I’ll fix the
[Joe Buck](http://www.welsh-buck.org/jbuck/) provided me with a well
worded response which essentially boiled down to “<em>Pete</em> is
likely to be violating <em>Fred</em>’s copyright” and “even if legal,
<em>Pete</em>’s action is not terribly respectful of <em>Fred</em>”.
James Ogden suggested that providing the plugin interface to
<em>FantasticUsefulApp</em>, against which <em>IncrediblyCoolPlugin</em>
was written, was both public and able to be used by a hypothetical
<em>FantasticallyUsefulApp++</em> written by another third party such
that <em>IncrediblyCoolPlugin</em> was immediately usable without
changes (or recompilation) then there is likely to be no issue with the
GPL vs. proprietary part of the question. As for bundling it all
together though, James couldn’t quite decide if this meant that
<em>SuperMegaCorp</em> had run the risk of violating the GPL or
infecting their app.
[Craig Sanders](http://taz.net.au/~cas/) gave a detailed response which
I will attempt to summarise as follows: The answer to <em>1.</em> is
that the user is free to do as they wish wrt. linking on their own
machine. No violation has occurred. <em>2.</em> is a violation because
the bundling of the plugin is not <em>mere-aggregation</em> in the terms
of the GPL. <em>3.</em> is not necessarily a violation of the GPL but
definitely feels unethical. Craig also points out that <em>3</em> is an
interesting turn-around of how Debian installs the Microsoft core fonts,
the flash plugin, etc.
[Neil Williams](http://www.codehelp.co.uk/) presented a strong argument
that the BSD licencing of the header files was a red herring and that
what matters is the licence of the object code implementing the
interface, which clearly is proprietary in this example. He again argued
that <em>1.</em> was not an issue as there was no distribution of the
object code involved. That <em>2.</em> is a clear violation of the GPLv2
on the part of <em>SuperMegaCorp</em> and that <em>3.</em> was a
violation of the spirit of the GPLv2 even if it were strictly speaking
within the terms of the licence.
Then the FTF-Legal mailing list was given a crack at the question.
Unfortunately I can’t find a link to the thread, and I doubt this
summary will do it full justice, so I guess someone needs to email me
with a link to the thread. Initially the impression was that the only
issue would arise in legal terms, were the plugin to be distributed
under the terms of the GPLv3. This was countered with the comment that
if age were the only factor in determining derivative works, then once
<em>SuperMegaCorp</em> released a new version of
<em>FantasticUsefulApp</em> it could be considered a derivative work of
<em>IncrediblyCoolPlugin</em> despite that not necessarily being the
case. Also the question arose about whether <em>2.</em> could be
considered more than mere aggregation if the app were advertised as
having the features of the plugin. Finally there was the suggestion that
<em>Pete</em> could simply allow for linking to the app in his licencing
of his plugin, however I’m not sure if that’s possible given he
aggregates <em>Fred</em>’s work in his plugin.
[Ean Schuessler](http://en.wikipedia.org/wiki/Ean_Schuessler) provided a
pithy response which given its terseness I shall include here in full:
<em>Pete</em> violated the GPLv2 when he introduced dependencies on
<em>FantasticUsefulApp</em> into a derived work of <em>HandyStuffs</em>
and subsequently distributed it. If <em>Pete</em> had kept
<em>IncrediblyUsefulPlugin</em> to himself then he would have been fine.
<em>Uhura</em> is also, arguably, guilty of at least contributory
infringement by participating in the distribution process.
Several others, some of which wished to remain anonymous, also replied
through various means which were not email as I had asked. I’m afraid I
didn’t spot blog postings made in response, so if any of you did, and
feel it can add to this redux, then please email me so I can add a link.
Everything else was essentially the same as, or equivalent to, all the
responses I have listed above.
Thank you all for your time and effort in this, the information gathered
has been very interesting and will definitely shape how I proceed with
writing plugins, and apps which use them, where any non-free licence may