[License-discuss] Strong and weak copyleft

[Lawrence Rosen]

Maybe we can summarize so far:

ULTRA-STRONG		(AGPL)
STRONG		(GPL)
MORE THAN WEAK	(LGPL)
ALMOST WEAK		(EPL)
WEAK			(MPL)
VERY WEAK		(APACHE)
ULTRA-WEAK		(CC0)

This rather simple scale is not reflected in copyright law or any relevant
cases. It is not part of the Free Software Guidelines or the Open Source
Definition. It bears no resemblance whatsoever to the definition of
"derivative work." It is based here in this thread on obscure quotes from
various websites or opinions about "license author's intent" without quoting
the actual provisions of the licenses that enable these vague distinctions. 

This is one of the issues raised by the VMware complaint in Germany, and
we're expecting a court to make a decision about how strong the GPL is. This
email thread is still not very helpful. 

/Larry