&gt; What countries? Has anyone in those countries ever been sued by using public domain works?<p>It&#x27;s a question of &quot;can you willfully put your work in the public domain&quot;, not &quot; is there an expiry on copyright&quot;. It&#x27;s also possible that some company&#x27;s lawyers might get unhappy if their company uses such a work.<p>&gt; And if they don&#x27;t respect Public Domain, why would they respect the CC0 license?<p>Becuase they still have copyright law, they just don&#x27;t have a concept of public donation.<p>&gt;How is writing &quot;CC0&quot; on the bottom of the page any different than writing &quot;Public Domain&quot; on the bottom of the page?<p>In western countries there&#x27;s essentially no difference. But because CC0 is an actual legal document that has provisions for jurisdictions that don&#x27;t recognise public domain as a concept, it&#x27;s a significant difference.