For Approval: GPLv3
matthew.flaschen at gatech.edu
Tue Aug 28 08:13:06 UTC 2007
Donovan Hawkins wrote:
> Case in point, this email. I quoted you, but I'm not saying those
> things. I am relaying the fact that you said those things to anyone who
> reads my email. That is all the BSDL requires of me...that I relay the
> fact that the original license said all those things. I don't have to
> repeat them myself and become bound by them myself.
That's a good way of explaining the difference between BSD and copyleft.
At first glance, BSD actually seems to be copyleft. After all, can't I
redistribute, modified or unmodified, binary or source, the entirety of
any program accompanied by BSD? But the problem is BSD only applies to
code copyright owners explicitly licensed under BSD. Microsoft includes
the BSD license with Windows, but that does not put any Microsoft code
under BSD. That would take /another/ BSD notice, or at least them
adding their copyright notice to the BSD license (and hopefully being
clear about what code was included in this grant).
That's why GPLv2 says:
"*You must cause* any work that you distribute or publish, that in whole
or in part [...] is derived [...] to be licensed [...] under the terms
of this License."
"*You must license* the entire work, as a whole, under this License to
anyone who comes into possession of a copy."
Licensing takes deliberate action, so copyleft licenses are careful to
require that deliberate action ("You must license") on the derived code.
Keeping an old notice around doesn't make it applicable for new code.
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