The Open Knowledge Definition (OKD) provides an answer to the question: what is open knowledge? It puts forward, in a simple and clear manner, principles that define open knowledge and which open knowledge licenses should satisfy.
After various improvements and lots of feedback over the last year to the initial draft, version 1.0 of the open knowledge definition is at last officially out along with a new dedicated subdomain at http://okd.okfn.org/. No doubt there are plenty of improvements still to be made so please get involved. In particular there’s an editable development version of the definition along with the beginnings of a list of ‘conformant’ licenses.