Subject: Re: Assistance/advice in choosing a license for POV-Ray 4.0
From: Chris Cason <>
Date: Thu, 24 Nov 2005 04:30:21 +1100

Chuck Swiger wrote:
> Unethical vendors who disregard the license are not going to be 
> affected by writing a more complex license.

Well, that's true if they want to break the law entirely. However I was
referring more to those vendors who want to remain within the law but
will do whatever they can to avoid the spirit & intent of the license,
such as doing some sort of unusual dynamic loading that isn't literally
'dynamic linking', for the specific purpose of avoiding derivative works
clauses (even if such applied for dynamic linked libraries).

To me that's 'unethical', even if it's legal.

>From my point of view, while there will always be folks who will violate
our license outright, they will generally tend not to be selling their
product commercially, simply because that in most jurisdictions makes
them a lot more legally vulnerable.

> ...but you should choose a license which meets your needs and suits 
> your users, whether or not that is OSD-compliant.

It's a bit of a quandary really. We really want to be OSD-compliant since
we don't want to discourage the use of our software within the OSS
community, and to an extent that currently happens, sometimes for
practical reasons, but I feel more often due to either misunderstandings
or outright bias against our license. For example even though we
explicitly allow OSS distribution of our software as per the OSS clause
in version 3.6, we still see OSS projects claiming they aren't allowed to
distribute POV-Ray, which is really frustrating to us.

An example of this can be seen at,
where Klaus points at our current license and claims it stops redistr-
ibution of knoppix CD's if POV-Ray is on it[1], despite the fact that
we went to the trouble of explicitly allowing knoppix by name!!![2]

Needless to say his claims are incorrect; we allow exactly this sort of
bundling yet we still have folks like him point at that very same license
and say "it says no". Note that this isn't a criticism of Klaus per se
(though I am disappointed that he didn't actually read the license before
saying what he did); it's a reflection of the fact that certain parts of
the OSS community have for a long time bad-mouthed POV-Ray's legacy
license, rightly or wrongly, and it appears that mud does stick. I
presume this is what influenced Klaus in the above case.

For that reason I am hesitant to have a non-OSI approved license since
anything that isn't clearly OSD-complaint will probably meet with the
same fate; folks won't bother to read it properly and will continue to
assume that our project isn't OSS-friendly. We don't want this because we
really do want to see our efforts used freely by as many people as
possible - the proviso being that we also don't want to see commercial
vendors take without giving.

-- Chris

[1] quoting Klaus:
      "Problem: povray is NOT FREE SOFTWARE. The license is incompatible
       with a free distribution for any purpose, including commercial
       ones. So, I'd rather remove kmovmodeler in 4.0.1."
      "You may NOT distribute povray commercially without restrictions,
       therefore a computer magazine, for example, could NOT include a
       Knoppix CD anymore if povray is in it, unless the magazine gets a
       written permission from the povray legal owners. Also, each and
       every redistributor pf a Knoppix with povray needs to also accept
       the quite complex povray REDISTRIBUTION license at" [snip]

[2] for those who want to check the clause for themselves, please see sections 2.1, 2.2
    and 4.1(c).