You are free: To share: To copy, distribute and use the database, To create: To produce works from the database, To adapt: To modify, transform and build upon the databases, as long as you: Blank: This section is intentionally left blank. The PDDL imposes no restrictions on your use of the PDDL licensed database. If you use the PDDL for any changes you make, the work stays free and open for all. CC0 is compliant with the Science Commons protocol for open data, as is the Open Data Commons PDDL. They are both interoperable, so any data or content made available under either system can be mixed and remixed. Unlike CC0 however, the Open Data Commons system includes a set of Community Norms that can be linked with the license.

Source: https://opendatacommons.org/licenses/pddl/summary/