[gdal-dev] Click through proprietary licensing

[Frank Warmerdam]

Folks,

I accidentally send this originally to gdal-dev instead of the
OSGeo4W list.  I'd like to move the discussion to the OSGeo4W
list.  I'm just cc:ing gdal-dev for notice.

Even Rouault wrote:
> Le jeudi 11 novembre 2010 19:55:27, Frank Warmerdam a écrit :
> 
> Yes, this is a tricky situation. 
> 
> In fact, the potential legal infringement doesn't come necessary only from the 
> side of the proprietary software. Even if you satisfy the licencing terms of 
> the former, the copyright holders of the GPL software could argue that the GPL 
> licence doesn't apply in that context.

Even,

Yes, this is the primary issue I was concerned when I mentioned GRASS.

> The issue is not using GPL and proprietary stuff, but distributing the 
> aggregation of the two. Whether the fact of distributing a GPL program 
> (QGIS/GRASS/...) that uses a X/MIT library (GDAL/OGR) that has a X/MIT plugin 
> (OCI driver, ECW driver, MRSID driver) that links to a proprietary plugin (OCI 
> library, ECW library, MRSID library, ...) is illegal or not is probably in the 
> gray area of the GPL ( there is always debate on how linking and GPL work : 
> http://en.wikipedia.org/wiki/GNU_General_Public_License#Linking_and_derived_works 
> )

Honestly, if everything is installed as part of OSGeo4W it does not seem
like a gray area to me.  It seems to be a clear violation of the GPL.

If the end user later adds a proprietary plugin of their own accord
then we are at least in a gray area or even in the clear.  But it isn't
my wish to try and subvert the GPL.

> 4) And the last sentence of clause 2 of GPLv2 could perhaps apply to OSGeo4W 
> situation : "In addition, mere aggregation of another work not based on the 
> Program with the Program (or with a work based on the Program) on a volume of 
> a storage or distribution medium does not bring the other work under the scope 
> of this License. ".

Certainly I don't see a problem installing GDAL+proprietary plugins
and some GPL'ed software that doesn't actually link to GDAL.  In this
case we only have aggregation.

> So we could probably say that those proprietary plugins are out of the scope 
> of the GPL licence, but I'm not 100% this is a valid interpretation...
> 
> Of course, there are some possible ways to solve this without ambiguity :
> a) either those proprietary stuff are licenced under a GPL compatible open-
> source licence... (well one can dream...)
> b) or the copyright holders of those GPL software agree to provide a special 
> exception clause to the GPL to allow it to be combined with proprietary 
> software. Not necessarily easy in the presence of multiple copyright holders.

One approach I have contemplated is having driver register some metadata
about their licensing class.  In this way a GPLed application could choose
not to register proprietary drivers and/or proprietary applications could
choose not to register GPLed (broadly reciprocally licensed) drivers.

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent