ODC Public Domain Dedication & License 1.0 (PDDL)
This licence is meant to be an international, database-specific equivalent of public domain dedication. At the same time, licence states that nobody can relicense or sublicense any database under PDDL because after a public domain dedication nobody longer own any rights to the database. It looks dubious that such prohibition is enforceable, and by whom? However, OKF (Open Knowledge Fundation) recommends this licence...