The Open Definition and Creative Commons

This chemspider blog post expresses considerable uncertainty as to the respective roles and relationship of the Open (Knowledge/Data) Definition and Creative Commons. This kind of uncertainty, particularly as to whether the OD and CC are in some way competing ‘standards’, is something I’ve increasingly encountered over the last year or so. I therefore really think this is something that it is important to clarify. Below is my effort to do so.

The Open Knowledge/Data definition is (like it says) a definition. It is not a license. In this respect it resembles the open source definition (on which it is modelled).
Its aim is to lay out a set of simple principles that make it clear what we mean when we say a ‘work’ (be it a dataset of a sonnet) is ‘open’. Informally this involves providing freedom of access, reuse and redistribution to the work (or rather providing freedom of access under a license that permits these things). The full set of principles can be found in the definition.
Like the open source definition it has a list of ‘conformant/compatible’ licenses. These may be found at: http://opendefinition.org/licenses/.
This is unlike Creative Commons whose explicit aim is to provide licenses. While all of the CC licenses are more ‘liberal’ (or ‘open’ even) than traditional copyright not all of the licenses are ‘open’ in the sense of the Definition.
This is not surprising — CC is about providing license choice and flexibility, not about providing a consistent set of licenses embodying a particular approach. In particular it is not the case that a particular CC license is ‘compatible’ with a given other CC license in the sense that one can intermix material made available under the different licenses. For example, any CC non-commercial license is incompatible with the CC Attribution-ShareAlike (by-sa) license.
By contrast one would hope and expect that any license which is conformant with the Open Knowledge/Data Definition would be compatible with any other such license — in the sense that one could freely combine two separate works made available under (different) open licenses together. This is important as one of the major benefits of an openness is to permit freedom of sharing and reuse in the open knowledge ‘commons’. Again this is very similar to the situation with the Open Source Definition.
Thus, in my opinion, the Definition is not a rival to Creative Commons but a complement which seeks to do something different. In particular the Definition does not develop licenses but CC does (many of which are conformant with the Definition). CC does not attempt to define a ‘standard’ but the Definition clearly does. By linking to a CC license you are saying: my stuff is available under this specific license. When you link to the Open Definition you are saying: my stuff meets this general standard.

As an aside: I think this is where some people may get misled by the Creative Commons name since the set of CC licenses do not (necessarily) result in the creation of a “commons” — works made available under different CC licenses cannot necessarily be mixed together. (This is not a criticism of CC, by the way. At lease in terms of licenses, CC is about a wide choice. However it is noteworthy that recent CC project’s such as ccLearn have, I belive, explicitly focused on a particular (open) license — in ccLearn’s case CC Attribution).