Home — Open Data Commons: legal tools for open data Overview & Contact Data

Open Data Commons provides legal tools and licensing options for people who publish, share, and reuse open data. It focuses on open data commons, open knowledge, and clear terms that help data owners decide how others can use their datasets. The site presents licenses, guidance, and reference materials that support open data practices across public sector, civic tech, research, journalism, and community publishing. The organization is best known for the Open Database License, or ODbL, a copyleft database license that encourages sharing and reuse while requiring derivative databases to remain open under the same terms. It also supports the Open Data Commons Attribution License, ODC-BY, which permits broad reuse with credit, and the Open Data Commons Public Domain Dedication and License, PDDL, which helps contributors dedicate data to the public domain. These tools help publishers address data content, define attribution, and clarify copyright or database right restrictions. The site serves a wide range of users, including government open data teams, nonprofit publishers, researchers, developers, journalists, and community groups that need reliable license language. It helps them choose a license, understand obligations, and publish datasets in ways that support transparency, collaboration, and redistribution. By offering plain-language legal options, Open Data Commons makes it easier for organizations to release data without creating unnecessary barriers. Its notable role is in shaping how open data is legally structured, especially for databases and machine-readable content. The project supports the broader open data movement by giving publishers confidence that their work can be reused, combined, and improved by others. For anyone searching for open data licenses, database rights, ODbL terms, or public domain dedication options, the site acts as a practical reference for legal and ethical data sharing.