On Wed, Mar 09, 2016 at 10:45:44AM -0800, Luis R. Rodriguez wrote:
To that end can someone provide:
* A lay review of copyleft-next 0.3.0's GPLv2 compatibility. Is
there anything that is obvious that makes it GPLv2 compatible ?
If so what is is?
Section 3 of copyleft-next 0.3.0 says:
3. Conditions for Distributing Derived Works; Outbound GPL Compatibility
If You Distribute a Derived Work, You must license the entire Derived
Work as a whole under this License, with prominent notice of such
licensing. This condition may not be avoided through such means as
separate Distribution of portions of the Derived Work. You may
additionally license the Derived Work under the GPL, so that the
recipient may further Distribute the Derived Work under either this
License or the GPL.
"Distribute" (a defined term in copyleft-next) would encompass GPLv2
"distribute". "Derived Work" (also a defined term) is defined in a
that is meant to correspond to "derivative work"/"work based on the
Program" in GPLv2 and "modified version"/"work based on the
in GPLv3. "GPL" is defined to mean a version of the GNU GPL or GNU
AGPL, including GPLv2.
The last sentence of Section 3 is based on the last sentence of MPL
2.0 section 3.3, which is generally understood to cause MPL 2.0 to be
compatible with GPLv2 and certain other GPL-family licenses, although
there is a difference in that copyleft-next is a strong (or at least
"non-weak") copyleft license. The idea here is that you can form a
Derived Work from code that is licensed under copyleft-next and code
that is licensed under, say, GPLv2. Under section 3, you can give such
code to a recipient under both copyleft-next and GPLv2. This gives the
recipient the option to distribute the Derived Work (presumably a
derivative work of the GPLv2 code) under GPLv2.
I hope that is clear. (In writing this, I see a way to improve the
formulation of that last sentence in section 3.)
Is there anything that makes it questionable if it is
GPLv2 compatible? If so what is is?
Well, I only noticed this now: maybe there is some argument that
copyleft-next section 3 brings about a noncompliance with GPLv2 in
situations where you are combining GPLv2 and copyleft-next code
(because GPLv2 says you have to license the entire modified work under
GPLv2). If so I'm not sure why I didn't notice that before. Anyway I
think a simpler approach is possible here.
Now there is also section 4, which says:
You may Distribute a Covered Work incorporating material
governed by a license that is both OSI-Approved and FSF-Free as of the
release date of this License, provided that Your Distribution complies
with such other license.
This wasn't meant to cover the situation where the non-copyleft-next
"material" is under the GPL. I think the implicit understanding here
was that the other license wouldn't necessarily clash with the strong
(or non-weak) copyleft policy of copyleft-next. So probably you can't
fit the GPL in this provision. I see a potential improvement here too.
I am going to try to make those improvements in the near future,
probably also releasing the improved version as 0.4.0.
* A lay review (perhaps a series of bullets) of what the main
advantages of copyleft-next 0.3.0 are over GPLv2
* It is much shorter and simpler
* It has an explicit patent license grant, unlike GPLv2
* Its notice preservation conditions are clearer
* More free software/open source licenses are compatible with it (via
* The source code requirement triggered by binary distribution is much
simpler in a procedural sense
* Recipients potentially have a contract claim against distributors who are
noncompliant with the source code requirement
* There is a built-in inbound=outbound policy for upstream contributions (cf.
Apache License 2.0 section 5)
* There are disincentives to engage in the controversial practice of copyleft/
* In 15 years copyleft expires, which can be advantageous for legacy code
* There are explicit disincentives to bringing patent infringement claims
accusing the licensed work of infringement (see 10b)
* There is a cure period for licensees who are not compliant with the license
(there is no cure opportunity in GPLv2)