Appendix 8: Recommended Data Licenses

Open Knowledge Foundation:24 These recommended licenses that are conformant with the principles laid out in the Open Definition (“Knowledge is open if anyone is free to access, use, modify, and share it — subject, at most, to measures that preserve provenance and openness”).30

License (SPDX IDs)	Domain*	Requires Attribution	Requires Share-alike	Comments
Creative Commons CCZero (CC0-1.0)	Content, Data	N	N	Dedicate to the Public Domain (all rights waived)
Open Data Commons Public Domain Dedication and Licence (PDDL-1.0)	Data	N	N	Dedicate to the Public Domain (all rights waived)
Creative Commons Attribution 4.0 (CC-BY-4.0)	Content, Data	Y	N
Open Data Commons Attribution License (ODC-By-1.0)		Y	N	Attribution for data(bases)
Creative Commons Attribution Share-Alike 4.0 (CC-BY-SA-4.0)		Y	Y
Open Data Commons Open Database License (ODbL-1.0)		Y	Y	Attribution-ShareAlike for data(bases)