We are looking for an open source license that...

[Chris F Clark]

1) requires users to return to us modifications made to the code for
   incoporation into a future version (whether they otherwise
   distribute those changes or not).

2) allows us to distribute code under other non-open source/non-free
   licenses (including the user contributions we have folded in).

3) prevents users from distributing our code in a non-open source
   manner (so we can compel those who wish to do so to buy the
   non-open source version).  We would prefer a license that also
   prohibits for-profit (or commercial) use in a non-open source
   manner, but that looks like a non-achievable goal while still using
   an open source license, since such a license would discriminate.
   (Most of our customers use our software to develop in-house, not
   for resale software, so we will certainly "leave some money on the
   table" with this strategy, but that's okay.  A license that
   considered redistribution within a company as distribution would
   also be a plus for the obvious reason.)

Does such a license exist?  I get the impression from reading this
group that several license writers are close to having developed such
a license.  We are not interested in developing such a license
ourselves and want to use someone elses.

Our situation--we have a non-open source piece of software that we
have been selling since 1990.  Over that time, we have repeatedly
considered releasing either an open source version of the software or
a non-commercial "gratis" version or both.  We will release an open
source version at the beginning of the year, if we can find an
acceptable license by then.

Hope this helps,
-Chris

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Chris Clark                    Internet   :  compres at world.std.com
Compiler Resources, Inc.       Web Site   :  http://world.std.com/~compres  
3 Proctor Street               voice      :  (508) 435-5016
Hopkinton, MA  01748  USA      fax        :  (508) 435-4847  (24 hours)
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