Open Database Licence 1.0

Share-alike database licence. Attribution and copyleft for databases.

The Open Database Licence (ODbL) is the database equivalent of CC BY-SA — a copyleft licence specifically drafted for databases. It addresses the legal complexity that databases sit at the intersection of copyright (which covers individual records or the structural arrangement) and the EU sui generis database right (which covers substantial extraction or reuse from a database). Plain CC licences originally handled this inconsistently.

ODbL is the licence governing OpenStreetMap, which is the most-cited example. The OSM community adopted ODbL in 2012 specifically because plain CC BY-SA had ambiguous coverage of database rights in EU jurisdictions and the ODbL's explicit drafting closed that gap.

The share-alike provision applies when a 'derivative database' is published — a concept ODbL defines more carefully than CC BY-SA defines its derivative-work concept. Combining an ODbL database with a non-ODbL database for analysis is generally permitted; publishing the combined database publicly triggers the share-alike obligation.