Searching for Creative Commons licensed content

Posted by: Tania Bedrax-Weiss, Software Engineer

If you've ever wanted to let your users only see content that is free to use and share (such as through Creative Commons), here are a few tips on how to do it. Assuming you've indicated the CC license in your pages, you can now specify that you want only content with specific licensing terms to show up in your CSE. We've made available four labels for CSE creators to use based on the CC licenses:

• free_use_share (by-nc-nd)
• free_use_share_commercially (by-nd)
• free_use_share_modify (by-nc-sa)
• free_use_share_modify_commercially (by-sa)

You can either use one of these labels as a background label to restrict all of your content to these terms, or you can reference these labels in the facet items section of the CSE specification and they will be exposed to users as additional refinements in your CSE. Note that these are filter labels; you cannot boost according to these labels.

As you generate content, please keep in mind that there are a number of ways Creative Commons licenses may be added to an HTML doc:

1. with <rdf:RDF>...</rdf:RDF> in the HTML head or body
2. using <meta name="DC.rights" content=uri of cc license>
3. using <a rel="license" href=uri of cc license>
4. using <rdf:RDF>...</rdf:RDF> in a comment

If your documents use any of these methods, we likely already have licensing information. See for example: http://joshua.smcvt.edu/linearalgebra/ that illustrates method number 3:

<a rel="license" href="http://creativecommons.org/licenses/by-sa/2.5/"> ...

and also illustrates method number 4:

<!-- <rdf:RDF xmlns="http://web.resource.org/cc/" ... >
<License rdf:about="http://creativecommons.org/licenses/by-sa/2.5/">...
</License>
</rdf:RDF> -->

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