Data is defined as open if "anyone is free to use, reuse, and redistribute it—subject only, at most, to the requirement to attribute and share alike" (Open Knowledge Foundation).
Opening your research data means taking on a shared responsibility within the scientific community. Openness makes your research more transparent, visible, and usable, as it allows researchers to reuse data produced by other research groups, thereby promoting faster progress in scientific research. This practice incentivizes, in the long term, innovation and also fosters international economic development.
At the same time, opening data doesn't mean granting unlimited access, but rather making it available as soon as possible and keeping it closed only for the strictly necessary time. In fact, open science aims to overcome barriers to accessing research results, promoting transparency and trust in the scientific community, but it also recognizes that there may be situations where the protection of intellectual property rights or the confidentiality of personal data require limitations on access or sharing.
The level of data openness and reuse is determined by the author by adopting a license (the use of Creative Commons licenses is suggested). According to Law 200 of 2021 (Art. 9bis), open research data must follow the FAIR principles and therefore must be released with a license that also allows for commercial purposes.
Some data, however, must necessarily remain closed as they are highly sensitive, such as non-anonymized personal data or data covered by trade secrets, or because they are not yet ready to be opened, such as raw data or data that still include confidential information. Therefore, these cannot be shared except through secure archives where only authorized users have access; however, it is advisable to share at least a description of such data through metadata.
To learn more:
Pavone, G. (2022). I dati dalla ricerca tra protezione e licenze per il riuso. Aspetti legali dei dati scientifici (in italian)