On Oct 23,  9:50pm, Thomas Mondoshawan Tate wrote:

> On Tue, Oct 23, 2001 at 04:22:39PM -0700, Kevin Buettner wrote:
[...]
>
> > There are several problems with "personal use only" licenses:
> > 
> >     1) It is sometimes difficult to differentiate between personal
> >        and commercial use.
> 
> How so? I would figure that having a direct clause like, "if you use this
> software for monetary gain" would be discriminatory enough to do this job.
> Where else would you sell the product for "monetary gain" except in a
> commercial enterprise?

You don't have to sell a product for it to be used for monetary gain. 
Let's use your example.  Suppose your game engine is ported by a game
developer to his favorite fringe operating system.  It is the developer's
intent to use the engine running on the fringe OS to develop data files
for a new game which he would sell.  (He'd sell just the datafiles, not
the engine.)

Clearly there is monetary gain going on here, but it is not being made
from sales of the game engine.  Rather the engine is being used as a
tool to help develop a new game.

You, the developer of the game engine, would probably not want to
discourage this sort of use because it is to your advantage to get
as many game developers as possible using your engine.  In order to
make money from the licensing of the game engine, you'd probably
want to set it up so that the engine is considered to be a sort of
library that the data files use.  If the engine were GPL'd, then
the source to the data files would have to be released under the
GPL too.  This is good in that the full source code to some games
might become available.  In order for a game developer to sell the
data files without making the "source code" to these files available,
they'd have to purchase a commerical use license for the engine.

....

IIRC, for many years ssh was in the same boat.  It used a rather
fuzzy non-commercial use license and it was really hard to pin down
whether it was acceptable or not for a software developer to use
ssh so that he could securely log into an employer's machine so that
he could do his work.  (Fortunately, we now have OpenSSH which was
based on an earlier version of ssh which didn't have the aforementioned
license.)

If you're going to use this kind of license, you must make it
painfully clear what kinds of activities are permitted and what
aren't.  Just saying that it can't be used for commercial gain won't
cut it.

[...]
> >     3) You are likely to incur the wrath of the open source / free software
> >        communities if your license is not open/free enough.
> 
> Hrm... From what I understood as the mission of the open source/free
> software movement was not to make the software "free" as in beer, but "free"
> as in distributable and hackable. As such, if the engine were to be licensed
> under such a license, wouldn't this follow the same principal?

Yes, BUT...

 1) Take a look at the clamor that surrounded the use of the NPL and MPL
    (Netscape Public License and Mozilla Public License).  To many folks,
    these licenses were acceptable, but then again to a lot of other folks
    they weren't.

 2) Similarly, take a look at the flame fests that occurred with regard
    to the various licenses used with Qt and KDE.

Kevin