On Tuesday, June 17, 2003, at 10:18 PM, David E. Konerding wrote:
This issue needs to be clarified in the licensing document because the document itself does not refer to extensions or define the nature of derived work, and because since the Chimera source code is not currently distributed (thus, those clauses are fairly irrelevant to most developers who write chimera extensions). It may be clear to the developers of Chimera whether extensions themselves are derivative, but it is not clear to an external user (as Ethan's message points out). The nature of extensions should be defined in the document because the idea of extension is conceptually core to Chimera and is the strongly preferred method of adding functionality to Chimera. I suspect that the Chimera developers believe that runtime-binding of Chimera functionality from an extension (such as a Chimera module import), and use of the Chimera object model does not render an extension a derivative work.
Extensions such as SSD and ViewFeature which are independently distributed are not in any way "proof" that extensions are not derivatives. It just means that the Regents have not llitigated against their independent distribution. If the Regents do not litigate to ensure that extensions comply with the derivative clauses of the license agreement, then the license loses much of its legal foundation. In other words, if you don't go to court to protect your intelletual property, then it's much easier for other people to use your intellectual property without crediting you.
Tom Ferrin should be returning from an out-of-town trip today, so I expect his feedback here soon. Just a couple of comments from me... The Python part of the Chimera source code is distributed. Eventually the C++ will be too, once the compilation process is organized and documented well enough that someone besides the internal developers would be able to follow it. According to Title 17, section 101 of the US code: A ''derivative work'' is a work based upon one or more preexisting works, such as a translation, musical arrangement, dramatization, fictionalization, motion picture version, sound recording, art reproduction, abridgment, condensation, or any other form in which a work may be recast, transformed, or adapted. A work consisting of editorial revisions, annotations, elaborations, or other modifications which, as a whole, represent an original work of authorship, is a ''derivative work''. So again, I think the license only restricts modification and redistribution of Chimera itself. I agree wholly that the license should state this explicitly, in terms a non-lawyer can understand. Eric Pettersen UCSF Computer Graphics Lab pett@cgl.ucsf.edu http://www.cgl.ucsf.edu