User:Lydia Pintscher (WMDE)/CC-0
Data in Wikidata is published under CC-0 and there are several reasons for this. I’ll go into them in more detail here.
Wikidata is here to give more people more access to more knowledge. This means we want our data to be used as widely as possible. CC-0 is one step towards that.
Reusability: Data is different from many other things we produce in Wikimedia in that it is aggregated, combined, mashed-up, filtered, and so on much more extensively. Our data lives from being able to write queries over millions of statements, putting it into a mobile app, visualizing parts of it on a map and much more. This means, if we require attribution, in a huge number of cases attribution would need to go back to potentially millions of editors and sources (even if that data is not visible in the end result but only helped to get the result). This is potentially computationally hard to do and and depending on where the data is used very inconvenient (think of a map with hundreds of data points in a mobile app). This is a burden on our re-users that I do not want to impose on them. It would make it significantly harder to re-use our data and be in direct conflict with our goal of spreading knowledge.
Ambiguity: Whether data can be protected in this way at all or not depends on the jurisdiction we are talking about. See this Wikilegal page on database rights for more details. So even if we would have decided to require attribution it would only be enforceable in some jurisdictions. Ambiguity, when it comes to legal matters, also unfortunately often means that people refrain from what they want to to for fear of legal repercussions. This is directly in conflict with our goal of spreading knowledge.
Leveling the playing field: Licenses that require attribution are often used as a way to try to make it harder for big companies to profit from openly available resources. The thing is there seems to be no indication of this working. Big companies have the legal and engineering resources to handle both the legal minefield and the technical hurdles easily. Who it is really hurting is the smaller start-up, institution or hacker who can not deal with it. With Wikidata we are making structured data about the world available for everyone. We are leveling the playing field to give those who currently don’t have access to the knowledge graphs of the big companies a chance to build something amazing. Thereby we are helping more people get access to knowledge from more places than just the few big ones.
Spread: CC-0 is becoming more and more common. Many organisations are releasing their data under CC-0 and are happy with the experience. Among them are the European Union, Europeana, the National Library of Sweden and the Metropolitan Museum of Modern Arts. Creative Commons has a list of additional prominent users of CC-0.
All this being said we do encourage all re-users of our data to give attribution to Wikidata because we believe it is in the interest of all parties involved. And our experience shows that many of our re-users do give credit to Wikidata even if they are not forced to.
Is this without downsides? No, of course not. Some people chose not to participate, some data can't be imported and some re-users do not attribute us. But the benefits I have seen over the years for Wikidata and the larger open knowledge ecosystem far outweigh them.