The Open Data Commons – Public Domain Dedication & Licence, commonly abbreviated as PDDL, is the first license to address open data, and in particular, sets of open data as part of an open database. As such it's suitable for licensing both large sets and individual records of library bibliographic, authority, and other library metadata.

The PDDL does for data what licenses like the GPL do for software. PDDL ensures that anyone can use, modify and distribute the records, or the entire database itself.

The entire ‡biblios.net record database is licensed under the Open Data Commons license, as are any contributed records by ‡biblios.net users. Please read the license for more information.