CC0 Technical Overview

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CC0 provides a framework that enables people to WAIVE all copyrights and related or neighboring interests that you have over a work. You can only do this if you hold the necessary rights for the work.

This page describes the metadata used to describe CC0 works along with suggestions for publishers who wish to use CC0.


CC0 introduces two new predicates in the Creative Commons namespace.

  • licenseOffer: The URI or (as generated by the beta CC0 chooser) blank node bundling the details of a license offer. A license offer can contain information regarding the specific license URI (license), the actor (cc:waivedBy, etc).
  • waivedBy: The URI of the actor (rights holder) waiving all legal rights to a work.


The CC0 application returns HTML with embedded metadata describing the role the user has selected, along with any additional metadata provided.

Waiving Rights

For example, a user waiving all rights to a work:

<p xmlns:cc=""
<a rel="license"
   href="" style="text-decoration:none;">
   <img src="" border="0" alt="CC0" /></a>
<br/>To the extent possible under law, <a rel="cc:waivedBy" href="">
<span about="" property="dc:title">A. User</span></a> has <a rel="license"
all copyright, moral rights, database rights, and any other rights that 
might be asserted over <a href=""><span about="" property="dc:title">Brilliance Described</span></a>.

Described in N3, the triples encoded in the above HTML are:

<> <> _:n0 .
<> <> "Brilliance Described" .

_:n0 <> <> .
_:n0 <> <> .

<> <> "A. User" .

As you can see, this metadata makes statements about both the work and the person waiving their rights over the work.


Creative Commons recommends marking works published under CC0 with embedded metadata. Metadata allows search engines and web software to find structured information about pages. The minimal recommended case is specifying CC0 as the license. Note CC0 is technically a waiver rather than a license but provides similar information regarding re-use rights. Therefore we reuse the existing, supported infrastructure.

For example:

All legal rights to this page have <a rel="license" 
href="">been waived</a>.

Additional metadata may be specified using the waivedBy predicate, which specifies a URI; publishers are encouraged to provide additional metadata about the actor at that location.