Is it possible to add a time clause to the license of an intellectual work?
<p>Would it be possible (and legal) to add the following copyright notice to an intellectual work (for example, a book):</p>
<blockquote>
<p>All rights reserved until January 1st 2030 and CC-BY license from this date.</p>
</blockquote>
<p>From what I understand, you can put anything in a copyright notice as long as the restrictions are less than what is required by law, but I don't know much about intellectual property law.</p>
<p>I am a citizen of the European Union (France).</p>

<p>I don't see any reason why one couldn't. I'm not sure that it would be wise, but it would probably be permissible.</p>
<p>The only hard question would be if the license could be revoked before that date if there was no consideration paid for the license and if no one had justifiably relied upon the grant of license. The grant of license would probably not be irrevocable if revoked before the date stated, although it might be hard to give notice to all affected parties to make the revocation binding as to all of them.</p>

copyright-notice