Open data is data that can be freely used, re-used and redistributed by anyone – subject only, at most, to the requirement to attribute and sharealike. –Open Data Handbook
The sharing of open data can be incredibly beneficial to society: facilitating enhanced scientific collaboration and reproducibility, increasing government and corporate transparency, and speeding the discovery and understanding of solutions to planetary and societal needs.
A big part of the potential value of data is realized by use across organizational and geographical boundaries. How does this occur legally? Increasingly, sharing of data is facilitated through the use of standard, public legal tools used to manage copyright and similar restrictions that might otherwise limit dissemination or reuse of data.
Many organizations, institutions, and governments are using Creative Commons licenses to share data. The CC0 Public Domain Dedication can be particularly important to maximize the re-use of data and databases, since it otherwise may be unclear whether highly factual data and databases are restricted by copyright or other rights. CC0 is intended to cover all copyright and database rights, so that however data and databases are restricted (under copyright or otherwise), those rights are all surrendered.
Open data policies are being adopted to ensure access to data—either as a raw material, or alongside other types of scholarly outputs. And data-specific repositories allow users to upload and share under CC licenses.