Hi all,

Who can give an authorative answer regarding distributing PostgreSQL 
under a different license?

In particular, the front page claims that PostgreSQL is under the BSD 
license. The problem is that there are two. The four clause license, 
which is not GPL compatible, and the three clause, which is.
Then again, the license itself is neither three not four clause. It is 
somewhat similar to the X11 license, though not identical.

The problem is this:
I'm using some code adapted from the PostgreSQL sources in the OLE DB 
provider, which is LGPL. I am not sure whether the PostgreSQL license is 
LGPL compatible, or what I need to do in order to use it. I have already 
placed copyright notices copied from the file I copied the actual code 
from, but do I need to do anything else? Is it at all possible to do 
this relicensing?

          Shachar

-- 
Shachar Shemesh
Lingnu Open Source Consulting
http://www.lingnu.com/


Thu, 22 Apr 2004 12:35:20 +0300
Shachar Shemesh <psql@shemesh.biz>
License question
Shachar Shemesh <psql@shemesh.biz> writes:
> In particular, the front page claims that PostgreSQL is under the BSD 
> license. The problem is that there are two.

We use the one shown in the COPYRIGHT file in the top directory of the
source tree, which is also available for your reading pleasure by
clicking on the "license" link on that same front page.

			regards, tom lane

Thu, 22 Apr 2004 08:58:36 -0400
Tom Lane <tgl@sss.pgh.pa.us>
Re: License question 
Tom Lane wrote:

>Shachar Shemesh <psql@shemesh.biz> writes:
>  
>
>>In particular, the front page claims that PostgreSQL is under the BSD 
>>license. The problem is that there are two.
>>    
>>
>
>We use the one shown in the COPYRIGHT file in the top directory of the
>source tree, which is also available for your reading pleasure by
>clicking on the "license" link on that same front page.
>
>			regards, tom lane
>  
>
Ok, let me explain the issue in a finer point.

The license given in the web link you mention seems to mandate all 
related work to be under the same license, which is nowhere near what 
BSD means. In particular, this puts some doubt on whether I can use the 
code in an LGPL project.

Can anyone shed more light on this point for me? Am I misreading 
something? If it is possible to put code into an LGPL project, what is 
the requirement?

-- 
Shachar Shemesh
Lingnu Open Source Consulting
http://www.lingnu.com/


Thu, 22 Apr 2004 16:19:21 +0300
Shachar Shemesh <psql@shemesh.biz>
Re: License question
Shachar Shemesh wrote:
> Tom Lane wrote:
> 
> >Shachar Shemesh <psql@shemesh.biz> writes:
> >  
> >
> >>In particular, the front page claims that PostgreSQL is under the BSD 
> >>license. The problem is that there are two.
> >>    
> >>
> >
> >We use the one shown in the COPYRIGHT file in the top directory of the
> >source tree, which is also available for your reading pleasure by
> >clicking on the "license" link on that same front page.
> >
> >			regards, tom lane
> >  
> >
> Ok, let me explain the issue in a finer point.
> 
> The license given in the web link you mention seems to mandate all 
> related work to be under the same license, which is nowhere near what 
> BSD means. In particular, this puts some doubt on whether I can use the 
> code in an LGPL project.

Where do you see that?  No one else has seen that requirement before,
and such a requirement doesn't exist.

> Can anyone shed more light on this point for me? Am I misreading 
> something? If it is possible to put code into an LGPL project, what is 
> the requirement?

None.  Just don't sue us.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Thu, 22 Apr 2004 11:08:52 -0400 (EDT)
Bruce Momjian <pgman@candle.pha.pa.us>
Re: License question
On Thu, 2004-04-22 at 09:19, Shachar Shemesh wrote:
> The license given in the web link you mention seems to mandate all 
> related work to be under the same license, which is nowhere near what 
> BSD means.

What license text do you think implies this?

-Neil



Thu, 22 Apr 2004 11:40:43 -0400
Neil Conway <neilc@samurai.com>
Re: License question
Neil Conway wrote:

>On Thu, 2004-04-22 at 09:19, Shachar Shemesh wrote:
>  
>
>>The license given in the web link you mention seems to mandate all 
>>related work to be under the same license, which is nowhere near what 
>>BSD means.
>>    
>>
>
>What license text do you think implies this?
>
>-Neil
>
>
>  
>
provided that the above copyright notice and this paragraph and the 
following two paragraphs appear in all copies.

I read that to mean that all copies must have the same license.

-- 
Shachar Shemesh
Lingnu Open Source Consulting
http://www.lingnu.com/


Thu, 22 Apr 2004 19:01:50 +0300
Shachar Shemesh <psql@shemesh.biz>
Re: License question
Shachar Shemesh <psql@shemesh.biz> writes:
> Neil Conway wrote:
>> What license text do you think implies this?

> provided that the above copyright notice and this paragraph and the 
> following two paragraphs appear in all copies.

> I read that to mean that all copies must have the same license.

No, that says that you can't remove the copyright notice from files that
have it.  It doesn't say that nearby files have to have the same
license.  (Compare to the GPL, which *does* say that.)

The bottom line here is that you cannot relicense code you didn't write;
this is generally true no matter what license it is distributed under.
You can take some Postgres pieces and use them in a project with a
different overall license, but those pieces are still under BSD license.

			regards, tom lane

Thu, 22 Apr 2004 12:26:56 -0400
Tom Lane <tgl@sss.pgh.pa.us>
Re: License question 
Tom Lane wrote:

>No, that says that you can't remove the copyright notice from files that
>have it.  It doesn't say that nearby files have to have the same
>license.  (Compare to the GPL, which *does* say that.)
>
>The bottom line here is that you cannot relicense code you didn't write;
>this is generally true no matter what license it is distributed under.
>  
>
No it isn't. If I write code under the LGPL, for example, all you have 
to do in order to relicense it is make sure you live up to all of my 
requirements.  In particular, this means that you CAN relicense it as 
GPL, without asking for my permission. Distributing it as GPL makes sure 
all of my restrictions are met.

If I relicense this code as LGPL, however, I cannot guarentee that all 
of my derived work will have the banners (the LGPL does guarentee that 
the copyright notice stay). Hence, I read it as "you cannot use this 
code in an LGPL project".

>You can take some Postgres pieces and use them in a project with a
>different overall license, but those pieces are still under BSD license.
>  
>
But that's not the BSD license.

>			regards, tom lane
>  
>
But that, in turn, means I cannot put them in an LGPL licensed project 
(or in a proprietary one, but that's not my problem). The LGPL requires 
that all files under the same project be under the LGPL.

The BSD license, in contrast to PostgreSQL's, does NOT require me to 
copy license related texts around, only the copyrights themselves. It 
does pose certain restrictions on what I am allowed to do with the 
copyrights, but any modern free software license (GPL included) require 
that you keep the copyright notices around

Now, I'm not trying to heal the world. It's enough to me that the 
current copyright owners give me permissions to use the code under the 
LGPL license. I am saying that calling the PostgreSQL license "BSD 
license" is misleading.

I'll also mention that I am, very likely, wrong in my interpretation of 
the license. The PostgreSQL license is very similar to the X11 license 
(http://www.x.org/Downloads_terms.html), which is interpreted by the FSF 
to be GPL compatible 
(http://www.fsf.org/licenses/license-list.html#X11License). This means 
I'm defnitely missing something here. What, however?

Oh, or is the license in my link the NEW X11 license, known to be 
non-GPL compatible?

-- 
Shachar Shemesh
Lingnu Open Source Consulting
http://www.lingnu.com/


Thu, 22 Apr 2004 19:49:38 +0300
Shachar Shemesh <psql@shemesh.biz>
Re: License question
Shachar Shemesh wrote:
> Can anyone shed more light on this point for me? Am I misreading
> something? If it is possible to put code into an LGPL project, what
> is the requirement?

You have to display the PostgreSQL license text in the source code or 
the binary, depending on what you ship.  A strict interpretation would 
say that considering the combined work, this is an additional 
requirement on top of the [L]GPL, so it is not allowed by the terms of 
the [L]GPL.  (But it is allowed by the terms of the PostgreSQL 
license.)  A looser interpretation would say that what the PostgreSQL 
license text says is essentially a subset of what the [L]GPL already 
says anyway, so adding the requirements of the PostgreSQL license on 
top of it does not actually impose additional requirements, so there is 
no problem.  Which one of these interpretations you believe is between 
you and the copyright holders of that LGPL'ed work, but the PostgreSQL 
copyright holders don't care.


Thu, 22 Apr 2004 18:56:46 +0200
Peter Eisentraut <peter_e@gmx.net>
Re: License question
Peter Eisentraut wrote:

>Shachar Shemesh wrote:
>  
>
>>Can anyone shed more light on this point for me? Am I misreading
>>something? If it is possible to put code into an LGPL project, what
>>is the requirement?
>>    
>>
>
>You have to display the PostgreSQL license text in the source code or 
>the binary, depending on what you ship.  A strict interpretation would 
>say that considering the combined work, this is an additional 
>requirement on top of the [L]GPL, so it is not allowed by the terms of 
>the [L]GPL.  (But it is allowed by the terms of the PostgreSQL 
>license.)  A looser interpretation would say that what the PostgreSQL 
>license text says is essentially a subset of what the [L]GPL already 
>says anyway, so adding the requirements of the PostgreSQL license on 
>top of it does not actually impose additional requirements, so there is 
>no problem.  Which one of these interpretations you believe is between 
>you and the copyright holders of that LGPL'ed work, but the PostgreSQL 
>copyright holders don't care.
>  
>
Unfortunetly, I'm the only LGPL copyright holder in this case. It's 
unfortunate because it means noone else has joined in on this project 
yet (OLE DB provider).

I'll be more than happy to accept your explanation (and it does fit in 
with FSF's assertation that the X11 license is GPL compatible). The only 
paragraph that bothered me to begin with was the one claiming I need to 
copy verbatim the license.

If all I am required to do is to make sure the license is ENFORCED by 
all of my derived work, then yes, the LGPL does that and I'm home free.

I still think you should change the text on the front page to read, at 
the very least, "PostgreSQL is distributed under a flexible X11 like 
license". "BSD" is too misleading, and most people know the X11 license 
by now.

          Shachar

-- 
Shachar Shemesh
Lingnu Open Source Consulting
http://www.lingnu.com/


Thu, 22 Apr 2004 20:09:27 +0300
Shachar Shemesh <psql@shemesh.biz>
Re: License question
Shachar Shemesh wrote:
> Neil Conway wrote:
> 
> >On Thu, 2004-04-22 at 09:19, Shachar Shemesh wrote:
> >  
> >
> >>The license given in the web link you mention seems to mandate all 
> >>related work to be under the same license, which is nowhere near what 
> >>BSD means.
> >>    
> >>
> >
> >What license text do you think implies this?
> >
> >-Neil
> >
> >
> >  
> >
> provided that the above copyright notice and this paragraph and the 
> following two paragraphs appear in all copies.
> 
> I read that to mean that all copies must have the same license.

It just means you can't remove the original license file.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Thu, 22 Apr 2004 14:32:44 -0400 (EDT)
Bruce Momjian <pgman@candle.pha.pa.us>
Re: License question

> I still think you should change the text on the front page to read, at 
> the very least, "PostgreSQL is distributed under a flexible X11 like 
> license". "BSD" is too misleading, and most people know the X11 license 
> by now.
> 

http://www.freebsd.org/copyright/freebsd-license.html

http://www.postgresql.org/licence.html

They look very similar to me. What's the difference?

Also, I'm a little confused. If you mix some postgresql-licensed code
with some (for example) gpl-licensed code, is the end result:
(a) GPL, since that's the more restrictive of the two; or
(b) The gpl code is still gpl, and the postgresql code is still
postgresql-licensed?

"b" makes more sense to me, since I don't see how you can "relicense"
the code if it's not yours.

Also, can you license code at all if it isn't yours? I would assume you
would have to make changes and license the changes you made, and
distribute it along with the postgresql-licensed code.

Regards,
	Jeff Davis


Thu, 22 Apr 2004 17:34:49 -0700
Jeff Davis <jdavis-pgsql@empires.org>
Re: License question
Jeff Davis <jdavis-pgsql@empires.org> writes:
> Also, can you license code at all if it isn't yours? I would assume you
> would have to make changes and license the changes you made, and
> distribute it along with the postgresql-licensed code.

You can't relicense code you don't own (if Shachar thinks differently
I suggest he talk to a lawyer).  What you can do is choose a license for
*your modifications and additions* to that base code.  When working with
BSD-tradition base code, there is hardly any restriction on what license
you use for your own work (at least, not from the BSD side --- see below).

When working with GPL or LGPL base code you are constrained to use the
same license as the base.  You still own your own work, but you can't
redistribute the combined work unless you use the same license.

I don't think you could reasonably choose GPL as the license for your
mods/additions, since by my reading of the GPL it would forbid you from
redistributing a combined work that's not all GPL.  But you could choose
LGPL, or any of the other standard free licenses.

			regards, tom lane

Thu, 22 Apr 2004 22:44:21 -0400
Tom Lane <tgl@sss.pgh.pa.us>
Re: License question 
Tom Lane wrote:

>Jeff Davis <jdavis-pgsql@empires.org> writes:
>  
>
>>Also, can you license code at all if it isn't yours? I would assume you
>>would have to make changes and license the changes you made, and
>>distribute it along with the postgresql-licensed code.
>>    
>>
>
>You can't relicense code you don't own
>
Sure you can.

> (if Shachar thinks differently
>I suggest he talk to a lawyer).
>
I have. And one who specializes in free software licenses, at that.

Let's give an example which is simpler, and therefor may make the case a 
little clearer. Supposed you painted a picture and give out electronic 
versions of it (you have the copyright). You allow everyone to 
redistribute the picture, so long as the general tone of the background 
color remains blue (license, pretty permissive).

Now let's suppose I take your picture and make several modifications on 
it, but none that violates your license (i.e. - the background is still 
blueish). Both of us have copyright over the new work, but I may only 
distribute it under a license that makes sure that the restrictions I 
received it under are met. This means I cannot public domain the 
picture. If I do, I am violating your copyright over the picture, as I 
can no longer guarentee that the background remains blue. In that sense, 
I cannot "relicense" the picture. This is the case even if my public 
domain copies still have a blue background, as I have now given people 
permission to change a work of art for which you hold a copyright, 
outside of the permission you have given either them or me.

One obvious solution is to redistribute it under the original license - 
do whatever you like with it, so long as the background remains blue. 
That is, however, not the only one. I can also change the license to 
whatever I want, so long as I can assure you that your original 
requirements are met with any work derived from the new license. For 
example, it is perfectly ok to say "you can redistribute this picture, 
but you are not allowed to change anything about the color scheme". The 
new requirement encapsulates the original requirement, and your license 
is therefor not violated. I have, in fact, relicensed your work.

This applies even if I did not make any change to your original work at 
all. So long as I can show that all terms of your original license are 
met if people follow my new license, you have no quarrel with me. You 
requested that people don't change the background color theme. They 
can't if they can't change the color theme at all.

Now, obviously, if people can get a picture to me under a certain 
restrictive license, and they can get the exact same picture from you 
under a more permissive license, they are unlikely to get the picture 
from me. That is, however, market forces, not copyright licensing.

If you accept that, just replace "blue" with "free".

>(at least, not from the BSD side --- see below).
>
>When working with GPL or LGPL base code you are constrained to use the
>same license as the base.  You still own your own work, but you can't
>redistribute the combined work unless you use the same license.
>
>I don't think you could reasonably choose GPL as the license for your
>mods/additions, since by my reading of the GPL it would forbid you from
>redistributing a combined work that's not all GPL.
>
But the (new, not old) BSD license is "GPL compatible", which means that 
I can relicense your work released under the 3 clause BSD as GPL. The 
original 4 clause BSD is not GPL compatible, which means I cannot. 
Comparing restrictions, and whether license X can guarentee that all the 
restrictions imposed by license Y are still met, is what stands at the 
core of saying "license X is compatible with license Y".

>  But you could choose
>LGPL, or any of the other standard free licenses.
>  
>
Hmm, not really. As I'm talking about putting code from PostgreSQL into 
the OLE DB provider proper, the linking clause of the LGPL does not 
cover this. Let's make it clear - as the LGPL code is all mine, noone 
can do or say anything to me if I mix it with non-relicensed BSD code. I 
am not violating the BSD license, because it's still BSD, and the person 
doing the LGPL license violation is me, the copyright holder, so noone 
can have any qualm with this (it's the copyright holder that has to sue, 
and I won't sue myself). Doing this does mean that noone except me can 
touch this project without removing the BSD code (or relicensing, but 
I'm assuming here I accept your claim that I cannot relicense), except 
me. Creating free software with conflicting licenses code is legal but 
highly recommended against.

>			regards, tom lane
>  
>
Shachar

-- 
Shachar Shemesh
Lingnu Open Source Consulting
http://www.lingnu.com/


Fri, 23 Apr 2004 07:53:35 +0300
Shachar Shemesh <psql@shemesh.biz>
Re: License question
On Thu, 22 Apr 2004, Shachar Shemesh wrote:

> Tom Lane wrote:
>
> >You can take some Postgres pieces and use them in a project with a
> >different overall license, but those pieces are still under BSD license.
> >
> >
> But that's not the BSD license.
[...]
> The BSD license, in contrast to PostgreSQL's, does NOT require me to
> copy license related texts around, only the copyrights themselves. It

 From the BSD license template on the OSI site:

# Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
# Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.

So, afaics, it *does* require you to copy the list of conditions along
with the files.


Thu, 22 Apr 2004 22:50:09 -0700 (PDT)
Stephan Szabo <sszabo@megazone.bigpanda.com>
Re: License question
Shachar Shemesh kirjutas N, 22.04.2004 kell 19:49:

> The BSD license, in contrast to PostgreSQL's, does NOT require me to 
> copy license related texts around, only the copyrights themselves. It 
> does pose certain restrictions on what I am allowed to do with the 
> copyrights, but any modern free software license (GPL included)
> require that you keep the copyright notices around

* Copyrights by themselves do not give others any rights to use
copyrighted material, licenses do. Copyrights "reserve all rights" by
default.

* On can license only that for what he owns IP (copyright, patent, ...).

ergo, to allow other to use the code, there must be a license from the
copyright holder.

If you just keep the copyrights and not the license (either as full text
or reference) you either effectively deny others the right to use the
code as provided by you or claim ownership of code you do not really
own.

> Now, I'm not trying to heal the world. It's enough to me that the 
> current copyright owners give me permissions to use the code under the 
> LGPL license. I am saying that calling the PostgreSQL license "BSD 
> license" is misleading.

IIRC BSD stands for "Berkeley Standard Distribution", and as PostgreSQL
was originally released as free software from Berkeley under this
license it would be weird indeed to call it anything else.

----------
Hannu

Fri, 23 Apr 2004 09:34:17 +0300
Hannu Krosing <hannu@tm.ee>
Re: License question
Shachar Shemesh kirjutas R, 23.04.2004 kell 07:53:
> Tom Lane wrote:
> 
> >Jeff Davis <jdavis-pgsql@empires.org> writes:
> >  
> >
> >>Also, can you license code at all if it isn't yours? I would assume you
> >>would have to make changes and license the changes you made, and
> >>distribute it along with the postgresql-licensed code.
> >>    
> >>
> >
> >You can't relicense code you don't own
> >
> Sure you can.

You can only add additional restrictions for the combined code, not lift
original ones. That is unless the original licence allows it :)

You are free to relicence public domain code though, but I guess that by
doing so you kind of take ownership of your release verion.

IANAL

---------------
Hannu


Fri, 23 Apr 2004 09:47:04 +0300
Hannu Krosing <hannu@tm.ee>
Re: License question
> IIRC BSD stands for "Berkeley Standard Distribution", and as PostgreSQL
> was originally released as free software from Berkeley under this
> license it would be weird indeed to call it anything else.

FWIW, 'Berkeley Software Distribution'.


Fri, 23 Apr 2004 16:50:00 +1000 (EST)
Gavin Sherry <swm@linuxworld.com.au>
Re: License question
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- -- Shachar Shemesh <psql@shemesh.biz> wrote:

>  The new requirement encapsulates the original requirement, and your
> license is therefor not violated. I have, in fact, relicensed your work.

no, the license is only for the *combined* work (which includes your work).
Extracting the original picture, this picture is still under the "blue only"
license!


Ciao
  Alvar

- -- 
** Alvar C.H. Freude -- http://alvar.a-blast.org/ -- http://odem.org/
** Berufsverbot? http://odem.org/aktuelles/staatsanwalt.de.html
** ODEM.org-Tour: http://tour.odem.org/
** 5 Jahre Blaster: http://www.a-blast.de/ | http://www.a-blast.de/statistik/

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Fri, 23 Apr 2004 23:31:37 +0200
Alvar Freude <alvar@a-blast.org>
Re: License question