Dual licensing

[Marius Amado Alves]

I'm aware of the other replies (and FWIW I agree with them), and I can 
tell you (the OP) like short, so I'll be really short here, except for 
point 4, where I'll make a connection to "commercial open source".

> 1. Doesn't the GPL prohibit un-GPL'ing the code? Or does dual licensing rely on
> having files with identical content but different licenses?

It relies on that.

> 2. I'm uncomfortable with making contributors assign copyright to me, just so I
> can dual-license. Would it be sufficient to get them to send me a form email
> stating that they agree their contribution will be dual-licensed?

I think so.

> 3. Any GPL-compatible commercial license templates I can look at? Especially
> those that are clear and short.

I'd love to see one of those also!

> 4. The GPL obviously doesn't prohibit commercial activity on top of the
> software, since Red Hat et. al. use services as a commercial model. Is there
> any OSI-certified license that would either encourage or compel commercial
> activity to have to use a different, commercial license?

No. That would breach clause 6 of the OSD (as I think it was already 
noted). That's why the SDC Conditions  (www.softdevelcoop.org), a 
"commercial open source" licence, is not OSI-compliant. I quote the SDC 
Conditions because they try to cleanse a certain smell of parasitism of 
dual-licensing, namely that the dual-licensing model is practical only 
because the GPL is viral, as the previous note by Nick Moffitt indicates

	"Typically dual-licensing with a proprietary license is seen as
a buy-out.  Recipients may buy out their responsibilities under the
GPL, which they may be uncomfortable with.  Since the OSD requires
that the license may not restrict fields of endeavor, I believe that
discomfort with copyleft is going to be your most compelling argument
for your non-GPL license."

and because your questioning indicates convergence with the SDC 
philosophy, which is really simple: it's open source, but if it's used 
commercially, then the authors get a cut.


--
license-discuss archive is at http://crynwr.com/cgi-bin/ezmlm-cgi?3