Redistribution constraint

[Ian Lance Taylor]

"Andrea Chiarelli" <a.chiarelli at manthys.it> writes:

> > > The GPL constraint that imposes that every distribution must be licensed
> > > under the GPL itself is not a restriction on redistribution? Is not GPL
> an
> > > OS license?
> >
> > This type of restriction is considered to be acceptable.
> 
> 
> How can I distinguish an acceptable restriction from an unacceptable one?

By taking a step back and thinking about the goals of the OSD.  The
OSD is not a computer program.  It is intended to be a way to
articulate as clearly as possible, in English, the general consensus
of the meaning of "open source software."  It is based on the DFSG,
which was intended to articulate as clearly as possible the general
consensus of the meaning of "free software."

In that context, not permitting a license to require that
redistributions be under the same license would make no sense.  It
would rule out most accepted open source licenses, and in particular
the GPL.  The GPL is a canonical free software license, and any
definition of open source which excludes the GPL would not capture the
general consensus of "open source software."

Ian