RelLicense

RelLicense is both an elemental microformat (specifically rel license) and an RDFa statement. Example:

This text is licensed to the public under the <a rel="license" href="http://creativecommons.org/licenses/by-sa/2.5/">Creative Commons Attribution 2.5 License</a>.

• Subject: the current document/URI
• Predicate: license
• Object: http://creativecommons.org/licenses/by-sa/2.5/

Also see marking works.