On Tue, Jul 24, 2012 at 03:07:47PM -0300, Zooko Wilcox-O'Hearn wrote:
One particular detail of my TGPPL that I value and that I'm not sure
the TPL provides is that if you take advantage of the permission to
keep a derived work temporarily proprietary, then this obligates you
to offer the same permission to people who make worked derived from
your derived work.
I agree that's definitely a good thing to do. Keep in mind that what
I proposed as the TPL was a concept, and not something actually that
was actually implemented in terms of creating actual legal text that
could be used in a license. So I have to give great acknowledgement
to the TGPPL in that it has taken that (non-trivial) step.
Make sense? So when I publish source code under the TGPPL, I'm
not
offering people the option of making a derived work, keeping it
proprietary for a limited time, and then releasing it under a strict
copyleft which disallows others from making time-limited proprietary
derived works of it. On the other hand, I *am* offering people the
option of making a derived work, making it Free/Open immediately, and
disallowing others from making a proprietary derived work from it,
even for a limited time.
The latter option is currently the case for Tahoe-LAFS and the other
software that I release in this way because I offer the recipient the
choice of GPL or TGPPL. So if you want to make a derived work of
Tahoe-LAFS without allowing anyone "downstream" of you to make a
proprietary derivation of your work, even for a limited time, then you
can do so by releasing your derived work solely under GPL.
Ah, I see. But after the grace period as expired, does the code in
question become relicensed under "choice of TGPPL and GPL" again? I
assume it would have to be if the code is to be eligible to be merged
into the original codebase.
I'm interested in developing a "TGPPLv2" which is
expressed as an
"Additional Permission" to GPL. That would have exactly the same
consequences as the current TGPPLv1, sketched above, but it would
probably be better in a lot of ways to have it expressed as an
"Additional Permission" to GPLv3+.
There are some problems with giving people the power to create
derivitive works under a strict copyleft. For example, I know that at
least some people are not happy with a GPLv2 or v3 license,
specifically because someone could strip out the GPLv2 license. The
same is true of adding an additional permission which grants an
exception to the GPLv3 anti-tivoization clause. Anyone can strip it
out; and that's not necessarily something that the original copyright
holder might not want.
As one example, of the problems this can engender, consider the case
where a project has GPLv3 plus an anti-anti-Tivoization clause, and
then there are some personality issues, and someone decides to fork
the project, and in the process, they relicense the fork under a
strict GPLv3 license, without the anti-Tivo exception clause. Now the
any contributions that are made to the fork of the project can't be
merged into the original parent project, due to copyright
incompatibility issues; but the child project can always take
contributions made to the parent, and strip out the copyright commit
by commit. Some might argue that this would be an unfair situation;
it is certainly asymmetric.
So, I personally believe Free/Open software is a social good that is
massively, drastically under-produced, just as simple economic theory
would predict. I think -- or rather I hope -- that a better social
outcome is possible somewhere in the middle, between the two extremes
of 0 and ∞. TGPPL is my stab at it. We can't do much worse than we are
already doing.
Yes, this was exactly my thinking when I made the TPL proposal.
I think I had heard of the TGPPL in passing some time ago, but I had
completely forgotten about it until I read your e-mail --- and so
thank you for writing it, and more importantly, being willing to
experiment "outside of the box" as far as open source licensing
practices are concerned!
- Ted