[License-discuss] dual licensing and the Open Source Definition

Engel Nyst engel.nyst at gmail.com
Sat Dec 14 19:21:47 UTC 2013


On 12/12/2013 11:46 PM, zgilboa at culturestrings.org wrote:
> As per the Open Source Definition, commercial use of Open Source
> software must be permitted, yet "the license shall not require a
> royalty or other fee for such sale."
> One interesting side-effect of the above is that software can be
> released under a strong copyleft license, for instance the GPL, and
> yet be accompanied by the option to "buy one's way out of the
> license," thereby releasing the buyer from any and all obligation to
> make the modified source available to the public.

I'm not sure there's causality between the two. Commercial use must be
permitted (not denied, as in "non-commercial use"), and, there are other
business models than those based on copyright restrictions (fee per copy).

Commercial services around the software, customizations at user's place,
are a few other possibilities. They are alternatives to 
fee-per-copy-otherwise-restricted traditional models.
This is a major point, in my opinion, that should be understood.

However, indeed this isn't happening in the scenarios you're referring
to: proprietary-GPL dual licensing or open core business models are a
weird case that has emerged in practice. It's quite common place today;
I say weird not because it's uncommon (it's not) but for several other
reasons, among which one similar to yours if I understand you correctly:
this particular dual licensing doesn't seem to serve the goals intended
by the license (not by OSI). Whether you consider these goals focused to
assure software freedom/openness or to promote alternative business models.

> 1) to what extent does the GPL meet the OSI promise regarding the
> source of Open Source Software remaining open? After all, if vendors
> can take GPL'ed software and buy their way out of the license so that
> binaries, with or without changes, can be distributed without
> restriction and without a corresponding source, then something is
> probably not working the way it was originally intended.

It's an interesting perspective you seem to have, that GPL may be "at
fault" on this point. I'm not sure I disagree, depends what exactly you 
mean and where you're looking for improvements; but again, it has 
nothing to do (AFAICT) with OSD/OSI. Rather, I can see why among all 
licenses, GPL and AGPL are "favorites" in this game.

Copyright system is such that a license like GPL, which requires a
strong leveling of the playing field for contributors (nobody can use
copyright to restrict works/derivatives), is exposed /more/ in a sense
to copyright privilege when a single owner adds up for themselves
separate rights from all contributors. When one can what no one else can
(as opposed here to permissive licenses, where everyone can restrict
derivatives), that one has more power.

That's a philosophical matter, though, and it doesn't mean at all that
the GPL by itself doesn't work to keep software open. GPL and many other 
licenses make the software open source.

> Then again, it seems to me that the possibility to regulate one-time
> charges for commercial use from _within_ a license should be much
> preferred over a de facto option to bypass the license altogether.

See above on business models. (and please see below for another option)

On 12/13/2013 10:02 PM, zgilboa at culturestrings.org wrote:
> The framework in which I am interested would allow a distinction
> between derivative work in general, and changes to a specific library
> in particular.  In other words, I'm looking for a license that would
> guarantee source availability of all patches that were applied to an
> open source library, but not necessarily of the code that uses the
> interfaces which that library exports.

This goal (and only it) sounds like you may want to take a look at MPL
or LGPL. With MPL it's simple, files that contain code of the original 
work are covered by copyleft. Outside files (even within a "fork" of
the library/framework, though, note), are not bound to any condition.
Depending how you interpret derivative works (in copyright law, and add
the intention of LGPL licensors), LGPL copyleft seems to cover the
library/framework, but not the software using its API. The actual scope
is disputed though.
Also, there are others with approximately this scope.

On 12/13/2013 09:46 PM, zgilboa at culturestrings.org wrote:
> Here, too, my issue is with the idea that an effective open source
> license needs to be "upgraded" in order for software to become
> profitable for its copyright holder, or convenient for the vendors
> of commercial software that would like to use it. I am also not sure
> that a license that allows the modified source of a library to no
> longer be available is an "upgrade" to begin with, but that is of
> course subject to interpretation.

I sympathize with the sentiment. In any case, I don't think another 
license that is proprietary is an improvement.

> 2) Consider the case of an individual entrepreneur who created a
> software library, and who would like to require vendors of
> commercial products that _depend_ on that library to pay a _one-time
> fee_, but otherwise be permitted to use the library or distribute it
> in any way they see fit without additional charges, and provided that
> the original source code, along with all changes that were applied to
> it, remain available to the public. Would that author be able to
> release his/her library under an OSI-approved license? Having gone
> through the various licenses on the site, I was unable to identify a
> single license that adequately meets this scenario.

Licenses that require a fee per copy from commercial entities are not 
compatible with the Open Source Definition.

You may be interested in another experiment done with licensing to
address something similar enough (AFAIK): in some licenses, for a
limited time, like one year, proprietary derivatives are allowed, then
when the time elapses, their source is supposed to become automatically
open, under a copyleft license. You may want to look at this Transitive
Grace Period license[1] for an example (actually the best example I know 
of, others are proprietary or intended to; this isn't).
Please note that the license itself is not OSI-approved (the software 
using it is dual-licensed with GPL AFAIK, so there is still the GPL path 
for downstream).

[1] https://github.com/zooko/tahoe-lafs/blob/master/COPYING.TGPPL.rst

~ "Excuse me, Professor Lessig, but may I ask you to sign this CLA, so 
that we have legally your permission to distribute your CC-licensed words?"

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