[License-discuss] Idea for time-dependent license, need comments

[Karl Fogel]

zooko <zooko at zooko.com> writes:
>I suspect the Business Source Licence is inspired by my Transitive Grace Period
>Public Licence:
>
>https://tahoe-lafs.org/~zooko/tgppl.pdf
>
>https://tahoe-lafs.org/trac/tahoe-lafs/browser/trunk/COPYING.TGPPL.rst
>
>But, the Transitive Grace Period Public Licence is an Open Source licence.

Hi, Zooko!

I was going to say that TGPPL had not been submitted to the OSI for
evaluation as an open source license (nor, as far as I'm aware, has the
FSF evaluated it either)... but then I saw your point at the end that it
*has* been submitted before, though you don't say the outcome.  I don't
have the archive link handy, and unfortuntely they're a bit hard to
search for.  If you have a pointer, that'd be great.  I don't see it on
the list of approved licenses.

>There's a subtle difference between the Transitive Grace Period Public Licence
>and predecessors such as the Aladdin/Ghostscript thing. I've been having
>trouble explaining the difference to people. Maybe that's because it isn't
>important! But it seems important to me.
>
>The difference is that with the Transitive Grace Period Public Licence, there
>is no distinguished entity who has special privileges compared to the public.

Note lThe copyright owner is still special, as always.

>My company, https://LeastAuthority.com, writes software which is a derived work
>of TGPPL-ed software. There are two ways that this is totally different from
>the Aladdin-style licensing, and both of them have to do with
>LeastAuthority.com being bound to the same terms as anyone else.
>
>1. LeastAuthority.com doesn't have the option of changing our minds and *not*
>releasing our software under open source terms after the grace period expires.
>Because we're don't have a right to make a proprietary derived work of the
>upstream work (Tahoe-LAFS) *other* than under the Transitive Grace Period
>Public Licence, and that licence allows us to make a proprietary derived work
>*only* if it is a temporarily (12-month) proprietary derived work.

Right.  (If LeastAuthority were the copyright owner, though, then you
would have that option.)

>This matters to you as a user, because you don't depend on us taking any
>action, and you don't depend on us keeping our original plan instead of
>changing our minds. You can be assured that you have full Free and Open rights
>to our derived work 12 months after we distributed or hosted it, simply because
>we don't have the option to deny that to you.

As a matter of law, I don't know if any member of the public could
enforce that license, or if it would have to be the copyright owner (of
Tahoe-LAFS) who enforces it.  But whatever the answer is for the GPL,
it's probably the same for TGPPL.

>2. Any member of the public has the same right to make temporarily-proprietary
>derived works of *our* works, just as we had the right to make our derived work
>of the upstream work temporarily-proprietary. This opens up the possibility of
>an ecology of competing commercial improvements which can be kept proprietary,
>but only for up to 12 months each.

It also opens up a method of gaming the system, whereby every twelve
months someone creates a shell company, which then makes a "new"
derivative, while the old company "goes out of business", so there's
never any party that exists long enough for anyone else to enforce the
expiration of the grace period.

Just saying :-).

>To me, these are significant differences. To almost anyone else that I've ever
>talked to, they don't see the difference between TGPPL, Aladdin's practices,
>and this new Business Source Licence. Oh well. :-)

License comprehensibility turns out to be an important survival
criterion in open source, yeah...

>By the way, I submitted this licence to license-review several years ago, so
>you can find discussion of it in those archives.

(mentioned above)

Best,
-Karl