Concurrent Licenses?

[John Cowan]

"W. Yip" wrote:

> But doesn't this omit the fact that B's derivative 'bits' may evoke
> copyright subsistence, thereby requiring a concurrent license from B to C
> in addition to the license from A to C? Otherwise, C only has license to
> the initial program, but not the derivative 'bits'?

Indeed.  B has to grant C this license, though, under the terms of his
conditional right to create a derivative work from A's code.  So:

	A licensed code to B under the GNU GPL
	A licensed code to C under the GNU GPL
	A licensed code to D under the GNU GPL
	...
	B made a derivative work from A's code
	B distributes the derivative work to C
	B must license his parts to C under the GNU GPL,
		because if he does not, he has no rights from A any more.
 
> The bottom line is that A cannot license what he does not own. And A
> certainly cannot own B's copyright to the derivative 'bits' if these indeed
> do subsist.

No, but A can make it a condition of B's license to create derivative
works that he license his bits under the GNU GPL.

> Please explain what is "GPLs with no copyleft".

The term "GPL" is used equivocally in the literature: usually it means
the specific GNU General Public License; sometimes it refers to any
general public license, such as the X/MIT/newBSD license, the oldBSD/Apache
license, the Artistic License, and even unfree ones like the Aladdin
Public License.

These licenses do not impose any restrictions on the makers of derivative
works, and so lack the essential copyleft principle.  They have been
called "copycenter" licenses: i.e., take the code to the copy center and
make as many copies (or derivative works) as you want.

-- 

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Denn er genoss vom Honig-Tau,           || http://www.ccil.org/~cowan
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