Ryan S. Dancey
ryand at organizedplay.com
Tue Apr 10 07:47:47 UTC 2001
> You are describing copyleft. Not all Open Source software (nor Free
> is copyleft.
A copyleft is a legal mechanism of using a copyright license to require that
anyone who distributes a covered work must grant a license to the recipient
of that work with the same terms as the original license. It has nothing to
do with source code.
I have authored a copyright license which uses a copyleft to enable the
distribution and modification of roleplaying game rules without any
reference to software of any kind.
Copyleft is a way of perpetuating copyright license terms forward to all
future recipients of the covered work. Combined with a clause restricting
modification of the copyright license, it creates an unchanging standard set
of rights that one inherits when one receives a copy of the covered work.
A "strong" copyleft forbids combining work licensed using the strong
copyleft with work that does not to create a derivative work. Using a
"strong" copyleft, one is given the choice of either making the whole work
compatible with the strong copyleft license, or forgoing the use of those
parts which cannot use the strong copyleft license. The GPL is a "strong"
copyleft because it has this requirement, not because it requires the free
distribution of sourcecode.
> the entire Free Software Movement (they spell is capitalized)
> agree that unrestricted licenses like MIT, BSD and Apache
> are indeed 100% Free Software licenses.
"free software" is software that is licensed to you using terms that
prohibit you from imposing a requirement of the payment of a fee on the
right of recipients of the software to make copies or redistribute the
The FSF argues that the BSD license is "free software" (free as in beer).
It also points out that the license does nothing to guarantee that it is
"Free Software" (free as in speach). It is very careful to say that the BSD
license is compatible with the GPL (because the BSD license really doesn't
do much at all) - which is not the same as saying that the BSD license is
>interchangeable< with the GPL. You cannot take something licensed using
the GPL, toss the GPL, and distribute it using just the BSD. It is
"compatible" with the GPL because it does not affect any of the rights the
GPL seeks to secure. It is a "free software license" because it does not
require the payment of a fee for the right to make and distribute copies of
The FSF argues that using a non-strong copyleft license is less than optimal
because doing so removes the pressure (in the form of the strong-copyleft)
on future developers to make their code Free as well. It admits that using
software licensed to you as free software, essentially regardless of the
terms, is ethical within the framework of the Free Software Foundation
because your Freedom has not been abridged - and if you change the terms of
the license or release a binary-only version to other people, then you are
the problem, not the original license terms.
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