ODRL Creative Commons Profile

Specification: 6 July 2005

This version:

http://odrl.net/Profiles/CC/SPEC-20050706.html

Latest version:

http://odrl.net/Profiles/CC/SPEC.html

Editor(s):

Renato Iannella, ODRL Initiative, renatoodrl.net

Copyright ODRL Initiative 2004-2005

Abstract

This Specification describes the semantics of the Creative Commons licenses and how they can be represented using a Profile of the ODRL rights expression language.

Status of this document

This document contains the ODRL Creative Commons Profile Specification. It has been reviewed by the ODRL Creative Commons Profile Working Group. and other interested parties and has been endorsed by the ODRL Initiative. It is a stable document and may be used as reference material or cited as a normative reference from another document. The ODRL Initiative's role in making the Specification is to draw attention to the document and to promote its widespread deployment. This enhances the functionality and interoperability of the ODRL services.

Comments on this document should be sent to the editor(s) and discussion of this document takes place on the working group mailing list.

This document was produced under the ODRL Initiative WG Process and Procedures document.

Table of contents

1 Overview

The Creative Commons [CC] project has created a number of licenses and semantics for describing usage rights over content. The CC licenses are primarily intended to convey the semantics to the end user of the content. The ODRL is an advanced rights expression language (REL) [ODRL]. The objective of this document is to outline a Profile of the ODRL REL that incorporates the semantics and licenses from CC. This will then enable those who require more advanced REL mechanisms to utilise both the CC license semantics and the ODRL REL features.

The requirements of this Profile are to:

• express the core CC semantics in the ODRL REL,
• allow additional expressiveness around the CC semantics, and
• define an XML Schema for the Profile.

2 Creative Commons Licenses

The CC Licenses are described by three major characteristics:

• Permissions - rights granted by the license
• Prohibitions - things prohibited by the license
• Requirements - restrictions imposed by the license

Each of these three characteristics contain specific values representing different Permissions, Prohibitions, and Requirements. Each also has a unique URI.

• Reproduction - the work may be reproduced

  http://web.resource.org/cc/Reproduction

• Distribution - the work (and, if authorized, derivative works) may be distributed, publicly displayed, and publicly performed

  http://web.resource.org/cc/Distribution

• DerivativeWorks - derivative works may be created and reproduced

  http://web.resource.org/cc/DerivativeWorks

• CommercialUse - rights may be exercised for commercial purposes

  http://web.resource.org/cc/CommercialUse

• Notice - copyright and license notices must be kept intact

  http://web.resource.org/cc/Notice

• Attribution - credit must be given to copyright holder and/or author

  http://web.resource.org/cc/Attribution

• ShareAlike - derivative works must be licensed under the same terms as the original work

  http://web.resource.org/cc/ShareAlike

The complete list of all CC license characteristics can be found in Appendix A.

There are a number of formal licenses defined by CC in version 2.0. These include various combinations of the above license characteristics. The primary licenses, including their unique URIs, include:

• Attribution

  http://creativecommons.org/licenses/by/2.0/

• Attribution-NoDerivs

  http://creativecommons.org/licenses/by-nd/2.0/

• Attribution-NonCommercial-NoDerivs

  http://creativecommons.org/licenses/by-nc-nd/2.0/

• Attribution-NonCommercial

  http://creativecommons.org/licenses/by-nc/2.0/

• Attribution-NonCommercial-ShareAlike

  http://creativecommons.org/licenses/by-nc-sa/2.0/

• Attribution-ShareAlike

  http://creativecommons.org/licenses/by-sa/2.0/

The purpose of this Profile is not to replace the standard CC licenses, but to allow additional semantics to be expressed in separate ODRL offers or agreements.

3 Mapping to ODRL

The CC Permissions and Requirements map directly to ODRL Permissions and Requirements. ODRL already covers the semantics of CC Attribution and the others are defined in the Profile Data Dictionary (See Appendix A) and extension XML schema (See Appendix B).

CC defines two Permissions that all licenses include:

• Reproduction - the work may be reproduced
• Distribution - the work (and, if authorized, derivative works) may be distributed, publicly displayed, and publicly performed

• to copy the work, and
• to shift the work into another format as a verbatim copy.

The CC Distribution [CC-Full] includes the right:

• to distribute the work,
• to display or perform the work publicly, and
• to make digital public performances of the work (eg, webcasting).

Both Reproduction and Distribution are examples of new semantics that are captured in the ODRL/CC Profile (see Appendix A and B).

Given that there is an overlap in semantics of the new CC terms and the existing ODRL terms, new ODRL expressions should ensure that the final semantics are clear and unambiguous. For example, since the CC Reproduction right is broader than the ODRL Print right, any expression including CC Reproduction and ODRL Print repeats some of the same rights. However, there may be an issue if the Print right includes a Constraint, as then the two Permissions are in conflict. There is no general technical solution to this as the semantics involved are overlapping, so care must be undertaken when creating such expressions.

However, in the cases were the rights holder does wish to be more specific than the CC Reproduction right, then the expression should not include the CC Reproduction right but only the more specific ODRL Permissions and Constraints. For example, the rights holder may only wish that their work be displayed (publicly and privately) and printed once (privately). In this case the expression should include the ODRL display and print with a Constraint, and the CC Distribution right.

The current ODRL 1.1 model does not support the concept of CC Prohibitions. This is because the behavior of the ODRL model is that if a right (permission) does not explicitly appear in the expression then it is not allowed. Hence, in an ODRL expression, if Commercial Use was prohibited, then it would simply not be mentioned in the XML code. Conversely, if Commercial Use was explicitly allowed (such as the ODRL Sell permission), then it would appear in the XML code.

There are two ways in which the CC Commercial Use semantics can be represented in ODRL. The first way would be to define Commercial Use in the negative and to make this an ODRL Constraint. The second way would be to utilise the existing ODRL Purpose constraint and define a URI for non-Commercial use. For the purposes of this Profile, a new NonCommercialUse Constraint has been defined in ODRL, since this is considered to be more flexible and consistent.

It is also useful to add links from the ODRL expression to one of the standard CC Licenses. This allows access to the human-readable versions of the CC semantics, as well as linking the two machine expressions. The context of the entire ODRL expression can be used to indicate this reference link. Note, however, that referencing the CC License URI is an informative link - the ODRL expression is normative. In addition it is not recommended that a link to the CC license be used when the overall ODRL expression narrows (or restricts) the rights more than the original CC license.

4 Example Scenarios

Consider the scenario described on the CC website about Anita and her song Volcano Love. Anita chooses the Attribution-NonCommercial-ShareAlike CC license. We can now express that using the ODRL CC Profile, and include additional information about Anita (as the rights holder), and direct links to the content (asset).

<?xml version="1.0" encoding="UTF-8"?>
<o-ex:rights xmlns:o-ex="1.1/ODRL-EX"
  xmlns:o-dd="1.1/ODRL-DD"
  xmlns:cc="CC-20">
  <o-ex:offer>
     <o-ex:context>
        <o-dd:reference>http://creativecommons.org/licenses/by-nc-sa/2.0/
        </o-dd:reference>
      </o-ex:context>
    <o-ex:asset>
      <o-ex:context>
        <o-dd:uid>urn:anita-music:songs:volcanoLove.mp3</o-dd:uid>
      </o-ex:context>
    </o-ex:asset>
    <o-ex:permission>
      <cc:Reproduction/>
      <cc:Distribution/>
      <cc:DerivativeWorks/>
    </o-ex:permission>
    <o-ex:constraint>
      <cc:NonCommercialUse/>
    </o-ex:constraint>
    <o-ex:requirement>
      <o-dd:attribution/>
      <cc:Notice/>
      <cc:ShareAlike/>
    </o-ex:requirement>
    <o-ex:party>
      <o-ex:context>
        <o-dd:uid>urn:music-people:id-anita-001</o-dd:uid>
        <o-dd:name>Anita Music</o-dd:name>
        <o-dd:dLocation>anita@anita-music.biz</o-dd:dLocation>
      </o-ex:context>
      <o-ex:rightsholder/> 
    </o-ex:party>     
  </o-ex:offer>
</o-ex:rights> 

Extending the above example, lets say that Anita wants to make two additions. Firstly she wants to limit the Distribution permission to the USA only. Secondly, she wants to make clear the exact text that should be used for the Attribution requirement. In this case, the above example would be modified with the following two updated elements.

      <cc:Distribution>
        <o-ex:constraint>
          <o-dd:spatial>
            <o-ex:context>
              <o-dd:uid> urn:iso3166:US </o-dd:uid>
            </o-ex:context>
          </o-dd:spatial>     
        </o-ex:constraint>
      </cc:Distribution>

      <o-dd:attribution>
        <o-ex:context>
          <o-dd:remark>
              This work created by Anita Music with lyrics by
              Mary Music and sound by Jacky Music. 
          </o-dd:remark>
        </o-ex:context>
      </o-dd:attribution>

Since the above Distribution permission is narrower than the original CC license, Anita removes the link from the reference element to the original CC license.

Next, Anita wishes to make the lyrics to her song available. Anita chooses the Attribution-NonCommercial-NoDerivs CC license as this is the closest. However, she decides that she only wants the public to print her lyrics no more than once, so she includes the Display and Print permission with a Count constraint. She does not include the Reproduction permission and does not include a Reference to the CC License (as the semantics are not the same).

<?xml version="1.0" encoding="UTF-8"?>
<o-ex:rights xmlns:o-ex="1.1/ODRL-EX"
  xmlns:o-dd="1.1/ODRL-DD"
  xmlns:cc="CC-20">
  <o-ex:offer>
    <o-ex:asset>
      <o-ex:context>
        <o-dd:uid>urn:anita-music:lyrics:volcanoLove.pdf</o-dd:uid>
      </o-ex:context>
    </o-ex:asset>
    <o-ex:permission>
      <o-dd:display/>
      <o-dd:print>
        <o-ex:constraint>
          <o-dd:count>1</o-dd:count>     
        </o-ex:constraint>
      </o-dd:print>
      <cc:Distribution/>
    </o-ex:permission>
    <o-ex:constraint>
      <cc:NonCommercialUse/>
    </o-ex:constraint>
    <o-ex:requirement>
      <o-dd:attribution/>
      <cc:Notice/>
    </o-ex:requirement>
    <o-ex:party>
      <o-ex:context>
        <o-dd:uid>urn:music-people:id-anita-001</o-dd:uid>
      </o-ex:context>
      <o-ex:rightsholder/> 
    </o-ex:party>     
  </o-ex:offer>
</o-ex:rights> 

Appendix A: ODRL/CC Profile Data Dictionary (Normative)

The Creative Commons Profile data dictionary definitions:

Note: The Constraint type maps to the CC Prohibits characteristic.

Appendix B: ODRL/CC Profile XML Schema (Normative)

The Creative Commons Profile data dictionary XML Schema:

<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema targetNamespace="CC-20"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns:o-ex="1.1/ODRL-EX" 
    xmlns:cc="CC-20"
    elementFormDefault="qualified" attributeFormDefault="qualified">
    <xsd:import namespace="1.1/ODRL-EX" 
                 schemaLocation="1.1/ODRL-EX-11.xsd"/>
    <xsd:element name="Reproduction" type="o-ex:permissionType" 
                 substitutionGroup="o-ex:permissionElement"/>
    <xsd:element name="Distribution" type="o-ex:permissionType"
                 substitutionGroup="o-ex:permissionElement"/>
    <xsd:element name="DerivativeWorks" type="o-ex:permissionType"
                 substitutionGroup="o-ex:permissionElement"/>
    <xsd:element name="Sharing" type="o-ex:permissionType"
                 substitutionGroup="o-ex:permissionElement"/>
    <xsd:element name="NonCommercialUse" type="o-ex:constraintType" 
                 substitutionGroup="o-ex:constraintElement"/>
    <xsd:element name="NonHighIncomeNationUse" type="o-ex:constraintType" 
                 substitutionGroup="o-ex:constraintElement"/>
    <xsd:element name="Notice" type="o-ex:requirementType"
                 substitutionGroup="o-ex:requirementElement"/>
    <xsd:element name="ShareAlike" type="o-ex:requirementType"
                 substitutionGroup="o-ex:requirementElement"/>
    <xsd:element name="SourceCode" type="o-ex:requirementType"
                 substitutionGroup="o-ex:requirementElement"/>
</xsd:schema>

The file location of this XML Schema is:

  http://odrl.net/Profiles/CC/CC-20.xsd

Appendix C: CC License Mapping (Normative)

The Creative Commons License definitions and corresponding XML elements required to express the license:

Note: The above elements would use the appropriate XML Namespace prefix.

Appendix D: References (Non-Normative)

[CC] Creative Commons Project <http://creativecommons.org/>

[CC-Full] Creative Commons - Baseline rights and restrictions in all licenses <http://creativecommons.org/learn/licenses/fullrights>

[ODRL] Open Digital Rights Language (ODRL), Version 1.1. <http://odrl.net/1.1/ODRL-11.pdf> Technical Specification, ODRL Initiative, August 2002

Appendix E: Acknowledgements (Non-Normative)

This specification is the work of the ODRL CC Profile Working Group. The contributions of the Working Group members to this specification are gratefully acknowledged. Active participants in the Working Group include (by alphabetical order): Jean-Noel Colin, Robin Cover, Karen Coyle, Melanie Dulong de Rosnay, Sharon E. Farb, Roberto Garcia, Lars Gunnarsson, Renato Iannella (WG Co-Chair), Mike Linksvayer (WG Co-Chair), Andy Powell.