In any data project, there are likely to be two components. The first is the data collected, assembled, or generated. Think of it as the raw content in the system. It could be hourly temperature readings from a sensor, the age of individuals in a survey, recordings of individual voices, or photographs of plant specimens. The second component is the data system in which the data is stored and managed.
We usually do not think of data content separate from the system in which it is stored, but the distinction is important in terms of intellectual property rights. The question is what, if anything, is protected by copyright. Data that is factual has no copyright protection under U.S. law; it is not possible to copyright facts. Not all data is in the public domain. A project might, for example, use copyrighted photographs; the photographs are part of the project’s “data.”
In many cases, the data in a data management system as well as the metadata describing that data will be factual, and hence not protected by copyright.A database, on the other hand, can have a thin layer of copyright protection. Deciding what data needs to be included in a database, how to organize the data, and how to relate different data elements are all creative decisions that may receive copyright protection.
Because of the different copyright status of databases and data content, different mechanisms are required to manage each. Copyright can govern the use of databases and some data content (that which is itself original), but contract law, trademarks, and other mechanisms are required to regulate factual data.
The three ODC licenses are:
Public Domain Dedication and License (PDDL): This dedicates the database and its content to the public domain, free for everyone to use as they see fit.
Attribution License (ODC-By): Users are free to use the database and its content in new and different ways, provided they provide attribution to the source of the data and/or the database.
Open Database License (ODC-ODbL): ODbL stipulates that any subsequent use of the database must provide attribution, an unrestricted version of the new product must always be accessible, and any new products made using ODbL material must be distributed using the same terms. It is the most restrictive of all ODC licenses.
Creative Commons (https://www.creativecommons.org/) also has a library of standardized licenses, and some of them apply to data and databases. The ODC-By license, for example, is the equivalent of a Creative Commons Attribution license (CC BY). CC BY licenses, however, require copyright ownership of the underlying work, whereas the ODC-By license applies to works not protected by copyright (such as factual data)
The two CC licenses that are of greatest relevance to data management are:
CC0 (i.e., "CC Zero"): When an owner wishes to waive her copyright and/or database rights, she can use the CC0 mark. It effectively places the database and data into the public domain. It is the functional equivalent of an ODC PDDL license.
Public Domain mark (PDM): It is used to mark works that are in the public domain, and for which there are no known copyright or database restrictions. It is possible to flag factual data as PDM in a database, for example, in order to make it clear it is free to use.
Selecting a data license
There is no single right answer as to which license to assign to a database or content. Note, however, that anything other than an ODC PDDL or CC0 license may cause serious problems for subsequent scientists and other users. This is because of the problem of attribution stacking. It may be possible to extract data from a data set, use it in a research project, and still maintain information as to the source of that data. It is possible to create a data set derived from hundreds of sources with each source requiring acknowledgement. Furthermore, the data in the other databases may not have originated with it, but instead sourced from other databases that also demand attribution. Rather than legally require that everyone provide attribution to the data, it might be enough to have a community norm that says “if you make extensive use of data from this data set, please credit the authors.”Sharing Research Data and Intellectual Property Law: A Primer. Carroll, Michael W. 2015. https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1002235. An introduction to the various kinds of property rights that can be associated with research data.
Open Licenses. Project Open Data. https://project-open-data.cio.gov/open-licenses/. The US Federal Government guide to open licenses and dedications.
CC0 (+BY). Cohen, Dan. 2013. https://www.dancohen.org/2013/11/26/cc0-by/. A call for using CC0 with data, tempered by an ethical obligation to attribute.
Data Citation Developments. Kratz, John. 2013/ https://datapub.cdlib.org/2013/10/11/data-citation-developments/. An update on efforts to standardize data attribution requirements.
How to License Research Data. Ball, Alex. 2012. https://www.dcc.ac.uk/resources/how-guides/license-research-data. Written with British law in mind, but it has a good discussion of the pros and cons of the ODC licenses.
Licensing Open Data: A Practical Guide. Korn, Naomi and Oppenheim, Charles. 2011. https://discovery.ac.uk/files/pdf/Licensing_Open_Data_A_Practical_Guide.pdf. Another guide written with UK law in mind, but with a helpful comparison of CC and ODC licensing options.
Open Data. Wikipedia. https://en.wikipedia.org/wiki/Open_data Why we can't use the same open licensing approach for databases as we do for content and software. Hatcher, Jordan S. https://www.semantic-web.at/news/jordan-s-hatcher-x22-why-we-can-x27-t-use-the-same-open-licensing-approach-for-databases-a