On Fri, Nov 30, 2012 at 2:57 PM, Denny Vrandečić <denny.vrandecic@wikimedia.de> wrote:
There is some confusion in this thread.

Thank you for trying to dispel the confusion. Unfortunately I think you are also confused, at least about what some of our concerns are.
In a few jurisdictions there are sui generis database rights. These cover complete databases - but they do not cover their individual data items. There are licenses built on top of these database rights, and ODBL is the one that is used by OSM.

These "few jurisdictions" include many (perhaps all?) EU countries. I gather Wikidata's phase 2 is starting with the Hungarian Wikipedia. Databases are protected by database rights under Hungarian law, so we need to be clear about their implications for Wikidata by the time phase 2 begins.
Unfortunately, CC-BY-SA and ODBL are not compatible. You can not take content licensed under one license and republish it under the other license. Thus follows that using ODBL for Wikidata does not relieve us from *any* of the possible legal issues that are mentioned here due to Wikidata using CC0 as a license.

I think we are talking about different legal issues. My main concern is about external databases, with rights held by other organisations, that we wish to host on Wikidata (in whole or in substantial part). 

See my earlier post (http://lists.wikimedia.org/pipermail/wikidata-l/2012-November/001239.html) for an example, based on the data in http://en.wikipedia.org/wiki/List_of_ceremonial_counties_of_England and the infoboxes for various county articles listed within. This data is licensed by the UK government under the Open Government License (OGL, http://www.nationalarchives.gov.uk/doc/open-government-licence/

I believe UK editors would be breaking their country's law if they uploaded a significant portion of this database to Wikidata without following the terms of the OGL. These include giving credit and linking to the license where possible. They could probably do this in an adhoc fashion through the reference field, but it would be much better to have proper support for license tracking built in.
Having different licenses for different data items in Wikidata, as was suggested here, is not possible, as single data items are not licensable.

My suggestion was that we keep track of licenses for different databases held in Wikidata, not for each individual item. 

I agree that item licensing is an inappropriate concept. Storing licensing info for databases at item level would seem possible as a fallback, however, if Wikidata has no direct support for databases.
If Wikidata was a collection of databases, like e.g. OKFN's DataHub, then it would make sense to provide for different licenses for each of these databases. But Wikidata does not have any notion of different databases. You cannot take a database and simply upload it to Wikidata.

Wikidata can certainly be thought of as a collection of databases (or parts of databases), regardless of whether Wikidata itself distinguishes between them.

I've only played around a little with Wikidata, and I'll take your word for it that simple uploads of databases are impossible. But based on what Wikidata promises to do, it must still be possible to upload them somehow.
Choosing CC0 now allows us to later switch to CC-BY-SA4 if we choose so, which actually does take care of database rights, unlike previous versions. Choosing ODBL would not allow us to do so.

Choosing CC0, and only CC0, is fine IMO for the interwiki links dealt with in phase 1. But I believe it is not adequate for phases 2 and 3. 

These phases will deal with data that in many cases has been sourced from external databases. In some jurisdictions, these are legally protected and any licensing conditions will have legal force on editors living there.
I hope that clarifies the discussion a bit. It is a murky legal area, which has not been much tested yet in courts, so there are some insecurities there.

Yes, there is some legal uncertainty, particularly over which law applies when data crosses borders. But I do not see this as a good reason to ignore the legalities either.

On Fri, Nov 30, 2012 at 2:59 PM, Denny Vrandečić <denny.vrandecic@wikimedia.de> wrote:
2012/11/30 Avenue <avenue42@gmail.com>
Yes, but in some jurisdictions the licenses are the only things allowing lawful use of the data (at least in sizeable portions). I'm concerned that we'd put some users, and maybe entire projects, at unnecessary legal risk if we ignore this.

You make it sound like we do not have a license in Wikidata. We do have a license, and this license allows the free reuse fo the data by any user or project without them running any legal risks.
Yes, we have a license, and I agree this should present no legal problems for newly created databases. My concern is about what it means for preexisting, externally created databases. Claiming that a OGL'd database (say) becomes CC0 when imported into Wikidata seems risky to me. But IANAL, so take my opinions with a grain of salt.