Are implicit dual-licensing agreements inherently anti-open?

[Alex Bligh]

Brian,

--On 21 July 2005 09:54 -0700 brianwc at OCF.Berkeley.EDU wrote:

With apologies for the long quotation:
> Hi,
>
> [SNIP]
>> The situation about "partial distribution" is where, for instance, B
>> sells some form of specialized hardware appliance, and only distributes
>> the modified executable with the hardware. Only those buying the
>> hardware can then ask for the source under the (unmodified) CDDL, GPL,
>> etc. Joe Public cannot (even if Joe is a contributor). What the OVPL
>> does additionally here is give the ID a right to request modifications,
>> where B is not making them publicly available.
>
> Someone is confused here. Let's figure out if it's you or me. I think you
> misunderstand the GPL's requirement of providing source when distributing
> a modification. Look at GPL Section 3:
>
> ...
> 3. You may copy and distribute the Program (or a work based on it,
> under Section 2) in object code or executable form under the terms of
> Sections 1 and 2 above provided that you also do one of the following:
>
>     a) Accompany it with the complete corresponding machine-readable
>     source code, which must be distributed under the terms of Sections
>     1 and 2 above on a medium customarily used for software interchange;
> or,
>
>     b) Accompany it with a written offer, valid for at least three
>     years, to give any third party, for a charge no more than your
>     cost of physically performing source distribution, a complete
>     machine-readable copy of the corresponding source code, to be
>     distributed under the terms of Sections 1 and 2 above on a medium
>     customarily used for software interchange;
> ...
>
> In your example B distributes hardware with a modified executable, i.e., B
> also distributes software. If that executable software were covered by the
> GPL, then B needs to satisfy 3a or 3b (assuming 3c is not relevant in this
> example.

Yes, with you so far - except the normal situation is that *source* (not
the executiable) is covered by the GPL, and thus if the derived work (the
executable) is supplied is distributed then it must be accompanied either
by the source code or the written offer.

> You say B "only" distributes the executable, so I take that to
> mean B doesn't provide source under 3a.

Yes.

> Consequently, B must provide
> source under 3b, that is, B must provide source to "any third party" not
> just those who buy the hardware/software.

Yes. You are correct in respect of the GPL (my apologies) at least under
one interpretation of 3(b). Another interpretation is that the offer is
made to the person to whom the software is distributed, that they may
demand that the distributor makes the source available to any third party.
However, it's not particularly relevant as the "partial distribution"
problem still applies if there is a distribution of source AND object code
under the GPL (i.e. 3(a) is taken), OR (more likely) if just modified
source code is distributed in which case there is no provision allowing
third parties to get hold of it.

However, the CDDL accords with what I said.
> Any Covered Software that You distribute or otherwise make available in
> Executable form must also be made available in Source Code form and that
> Source Code form must be distributed only under the terms of this
> License. You must include a copy of this License with every copy of the
> Source Code form of the Covered Software You distribute or otherwise make
> available. You must inform recipients of any such Covered Software in
> Executable form as to how they can obtain such Covered Software in Source
> Code form in a reasonable manner on or through a medium customarily used
> for software exchange.

(this implies to me the offer is to the distributed party at least
in practice because no-one but the recipients can find out how to
get it - similarly if only modified source code is distributed, there
is no provision for third parties to get it)

Nor is it true with the MPL
> Any Modification which You create or to which You contribute must be made
> available in Source Code form under the terms of this License either on
> the same media as an Executable version or via an accepted Electronic
> Distribution Mechanism **to anyone to whom you made an Executable version
> available**; and if made available via Electronic Distribution Mechanism,
> must remain available for at least twelve (12) months after the date it
> initially became available, or at least six (6) months after a subsequent
> version of that particular Modification has been made available to such
> recipients. You are responsible for ensuring that the Source Code version
> remains available even if the Electronic Distribution Mechanism is
> maintained by a third party.

(note the bit between '**' I added, which says there is no provision
for third parties to get hold of the modified source code to object
code which has not been distributed to them, nor is there any provision
for third parties to get hold of modified source code if merely the
modified source is distributed).

> Joe Public *can* get the source
> in this situation. Did you intend a different hypothetical? Or perhaps
> OVPL is designed based upon a misunderstanding of reciprocal licenses?

No, I just got used to reading the CDDL and the MPL and forgot the
GPL 3(b) (but not 3(a)) worked slightly differently. IE the example
was right for 2 licenses but was precisely the one not to pick for
the GPL - I should have used the example of just modified
source code being distributed, or source code and object code being
distributed together.

However, this is not the distinction I was trying to make.

My reply was to Michael Bernstein, who was talking about the ability of
Contributors (not the ID) to make proprietary versions. There is no such
ability in the OVPL (it's the same as the CDDL in this respect, or for that
matter the GPL). The bit of 3.3 (which grants the ID, not Contributors, the
right to use contributor's modifications in the ID's proprietary versions)
that gives the ID the right to require a distributor of modifications to
provide them to the ID applies only to modifications which are selectively
distributed, i.e. which are not made available to the general public
(either because source code is distributed alone to a selective group,
or because source code plus object code is distributed to a selective
group, or because object code is distributed to a selective group and
the source code is only made available to that group).

Alex