[Insight-developers] Linear algebra licensing and ITK 3.18 Release

[Luis Ibanez]

Hi Tom,

A quick correction about your comment:

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On Mon, Mar 15, 2010 at 7:15 PM, Tom Vercauteren
<tom.vercauteren at m4x.org> wrote:
> but the authors refer to their software as a GPL one:
>  http://www.eecs.northwestern.edu/~nocedal/lbfgsb.html
>  http://www.eecs.northwestern.edu/~nocedal/lbfgs.html
> even though this is not consistent with what is written on these pages
>  "This software is freely available for educational or commercial purposes."
>  "This software is freely available [...] all commercial products using it"
>
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The GPL license is indeed consistent with commercial applications.

That is, the GPL license does not forbid commercial applications.

Excluding commercial applications will make a license to be incompatible
with the Open Source definition, because it will exclude a "field of endeavor".

               http://www.opensource.org/docs/definition.php


The reason why many developers of commercial applications tend to
avoid creating derivative works from GPL licensed code, is that, if
they distribute their software (the derivative work), they will have to
do it under a GPL license and therefore, they will have to make their
source code available under a GPL license.

In practice, using the traditional "publishing model" that many software
companies have adopted, it has been hard for them to imagine how to
charge for the software, if their first customers can re-distribute it as well,
(and may do it for free).


It has become common to reduce the above observation to the simplified
(but incorrect) statement that: "Commercial developers will not use GPL".


The obvious counter example is:  RedHat.


And some less obvious are:

* Netgear
http://kb.netgear.com/app/answers/detail/a_id/2649
Many of their network routers run Linux, for example the WNR3500:
http://www.netgear.com/Products/RoutersandGateways/WirelessNRoutersandGateways/WNR3500.aspx

* Roku
(the network box that gives you Netflix connections).
http://staging.photobridge.roku.com/gpl.php

* TomTom
GPS Devices
http://www.tomtom.com/page.php?Page=gpl


Although,
of course, these are mostly hardware vendors.


     Luis