[CentOS] trying to understand OSS, GPL, BSD & other licensing model for software distribution.

Rudi Ahlers rudiahlers at gmail.com
Wed Oct 7 08:01:00 UTC 2009

On Wed, Oct 7, 2009 at 1:26 AM, Rainer Duffner <rainer at ultra-secure.de> wrote:
> Am 07.10.2009 um 00:18 schrieb Rudi Ahlers:
>> Hi all,
>> We are busy developing some software (some is web based, others not)
> Licenses are only about the source-access and how contribution/
> deviations are licensed.
> You can charge any amount you want for your GPL'ed stuff - but the
> source must be available for reasonable cost.
> So, if one of your licensees redistributes a copy for free, that's
> perfectly legal (for GPL).
> Charging for PHP-stuff has always been very difficult.
> Some use IONCUBE encoder etc.
> I don't know if charging for support actually makes a good business-
> model.
> You need a lot of contracts for that.
> BSD-licenses carry a lot less burden - but of course you can't just
> take a GPL'ed piece of code and re-distribute it with a BSD-licence.
> If your free product is GPL'ed and your commercial product is a
> derivative of that, it will also be licensed (well, need to be
> licensed) as GPL - if you give it away to somebody. If you keep it
> inhouse, nobody cares and nobody has a right to see the derivated
> source, just because it exists).
> You should really enlist the help of a law-professional in this field
> - the licensing-minefield has gotten more and more difficult to
> navigate in recent years.
> This is especially relevant in cases where you want to have "dual-
> licensed" stuff (as you mentioned).
> Rainer
> _______________________________________________

Hi Rainer,

Thanx for your input. My questions aren't really related to what I am
going to charge for the software, but rather how I'm going to license
it. Most of it was, and still is developed for in-house use, but some
clients have requested that they want the same software for their own

What I want todo is simple:
There will be some scripts (web based) & programs (for desktop use,
mostly on Windows, but with Linux server connectivity & management
included) that we want to distribute for free.
Then we want to sell a commercial version of the same software, but
with more features than the free one.

What I don't yet fully understand, is how do we license both versions
of the same script, so that if a community member writes an addon for
the free one, that other community members can benefit from it as
well? And more specific, is it possible to "force" them to
redistribute their code via our community network?

I see this a lot, for example with Joomla - which is free and anyone
can contribute extra addons, whether free or commercial back into the

But they don't have a commercial version of the same project. So I
want to know how do I license the commercial scripts with this in
mind? i.e. if I license them as GPL, do I need to disclose the source
code? Cause we're going to encrypt the additional commercial code of
the software.

Support on this will be in the form of: if we need to goto the client
and set it up for them, do updates, training, etc.

Zimbra is a good example of what we want to accomplish, but I honestly
don't have any experience with licensing, so I can't just "copy
another project" in this regard.

Kind Regards
Rudi Ahlers
CEO, SoftDux Hosting
Web: http://www.SoftDux.com
Office: 087 805 9573
Cell: 082 554 7532

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