The obvious place to go would be NCBI, which as a US government operation is by default in the public domain. If you look at the copyright statement (bottom left at http://ncbi.nlm.nih.gov) and scroll down a litle you will find:
[?] Molecular Database Availability
Databases of molecular data on the NCBI Web site include such examples as nucleotide sequences (GenBank), protein sequences, macromolecular structures, molecular variation, gene expression, and mapping data. They are designed to provide and encourage access within the scientific community to sources of current and comprehensive information. Therefore, NCBI itself places no restrictions on the use or distribution of the data contained therein. Nor do we accept data when the submitter has requested restrictions on reuse or redistribution. However, some submitters of the original data (or the country of origin of such data) may claim patent, copyright, or other intellectual property rights in all or a portion of the data (that has been submitted). NCBI is not in a position to assess the validity of such claims and since there is no transfer or rights from submitters to NCBI, NCBI has no rights to transfer to a third party. Therefore, NCBI cannot provide comment or unrestricted permission concerning the use, copying, or distribution of the information contained in the molecular databases.[?]
Now in practice NCBI has refused data with restrictions imposed on it. The HapMap project was an example of this where they tried to impose a restriction that no-one could patent results. So in a sense it is technically Panton Compliant, and I believe in practice as well. But this isn't as explicit and clear as we were really looking for when we drafted the principles. Nor is it prominent.
One thing we should do is list Panton Compliant data sources on the website. I'm not sure that pointing at CKAN per se is in and of itself particularly helpful.
@Egon Willighagen: Facts are not copyrightable, but a collection of facts is, and more over by default the creation of a item that falls under the jurisdiction of copyright law gives it copyright protect; though that does not in itself provide a solid grounds for defending the copyrights related to said collection.
@Egon Willighagen: Facts are not copyrightable, but a collection of facts are, and more over by default the creation of a item that falls under the jurisdiction of copyright law gives it copyright protect; though that does not in itself provide a solid grounds for defending the copyrights related to said collection.
Indeed, and this is why CC0 and PDDL waivers exists.