It is recommended that data is licensed as openly as possible, in line with the Open Access paradigm, as this provides the most extensive re-use options and is increasingly regarded as good scientific practice. A milestone in this regard is the Berlin Declaration on Open Access to Knowledge in the Sciences and Humanities from 2003, which has been signed by several hundred institutions to date.
However, it is also possible to work with data in a FAIR way, even if it cannot be made fully available without restrictions. Access limitations are compliant with the FAIR Principles as long as the conditions and paths for access are documented in a way that can be interpreted by both humans and machines. Different degrees of accessibility may apply to the data and its corresponding metadata.
Data can be FAIR even if they are not accessible to third parties, if they are only accessible to a specific group of people, or if they are accessible to everyone (open data). Different levels of restrictive access can also apply to various stages of the data life cycle or to different usage purposes. For example, new, experimental data may initially only be available to the producer and their group, then to consortium partners as the results are further developed, and finally to the public after publication. Personal sensitive data must never be publicly accessible and usable.
The digitisation of collection items often raises complex issues regarding copyright and usage rights for the collection objects and their digital representations. The 2021 amendment to German copyright law makes it easier to clarify rights and make digitised material more widely available via open access.
More information on the topic of rights clearance and licensing can be found in section R1.1. (Meta-)data are released with a clear and accessible data usage license.
Open-Access.Network – Information – Open-Access Primers – Arguments and Reservations