Here's an excerpt:
Over the last couple of years there has been substantial discussion about the licensing (or not) of (open) data and what "open" should mean. In this debate there two distinct, but related, strands:
- Some people have argued that licensing is inappropriate (or unnecessary) for data.
- Disagreement about what "open" should mean. Specifically: does openness allow for attribution and share-alike "requirements" or should "open" data mean "public domain" data?
These points are related because arguments for the inappropriateness of licensing data usually go along the lines: data equates to facts over which no monopoly IP rights can or should be granted; as such all data is automatically in the public domain and hence there is nothing to license (and worse "licensing" amounts to an attempt to "enclose" the public domain).
However, even those who think that open data can/should only be public domain data still agree that it is reasonable and/or necessary to have some set of community "rules" or "norms" governing usage of data. Therefore, the question of what requirements should be allowed for "open" data is a common one, whatever one"s stance on the PD question.