RDFa Working Group Charter

The mission of the RDFa Working Group is to support the developing use of RDFa for embedding structured data in Web documents in general. The Working Group will publish W3C Recommendations to extend and enhance the currently published RDFa 1.0 documents, including an API. The Working Group will also support the HTML Working Group in its work on incorporating RDFa in HTML5 and XHTML5 (as a followup on the the currently published Working Draft for RDFa 1.0 in HTML5).

The main directions of RDFa’s enhancements are:

  1. specification of an API for RDFa, usable for browsers and XML applications
  2. updates to the RDFa language that ease the practice of authoring RDFa
  3. definition of the semantics of RDFa attributes for XML languages in general

The goal is to maintain backward compatibility with RDFa 1.0 (although some small non-compatible changes with regard to the defaults on XML Literals, may be introduced). No radical redefinition of the RDFa language is envisaged.

Join the RDFa Working Group.

End date 31 July 2011
Confidentiality Proceedings are public
Initial Chairs Ben Adida (Creative Commons)
Manu Sporny (Digital Bazaar, Inc.)
Initial Team Contacts Ivan Herman (15%)
Usual Meeting Schedule Teleconferences: Weekly
Face-to-face: None planned


The RDF in XHTML Task Force, jointly managed by the Semantic Web Deployment and the XHTML2 Working Groups, published two documents in October 2009 that collectively describe RDFa 1.0. Since the release of these documents, RDFa has enjoyed many successes, including a number of independent implementations and the public backing of major search engine companies. Deployment by major public institutions, governmental sites, as well as private companies, incorporation into CMS systems, etc, have also come to the fore.

Although formally defined as a module of XHTML1.1, there is a demand for the adaptation of RDFa to newer generations of HTML. Also, the RDFa attribute set has already been adopted by other XML applications, including the SVG 1.2 W3C Recommendation, the DataRSS format proposed by Yahoo, and Version 1.2 of the OpenDocument (ODF) format. Consequently, there is a need for the consolidation of these developments in the form of updated Recommendations.


The goal of this Working Group is to make RDFa authoring easier, to ensure continued adoption of the technology in HTML, XHTML, and XML, and to help developers to create applications based on RDFa data. The main work items to be completed by this Working Group, are:

The primary target language for the API, as referred to above, is ECMAScript, although other languages may also be considered. Wherever appropriate the group should use the WebIDL formalism to specify its APIs. Also, the API is strictly an RDFa API, ie, it does not include a generic API for RDF data (“TripleStore API”). At the time of writing this charter, such standard TripleStore API does not exist (although several different libraries are in use). An RDFa API and a TripleStore API are clearly related. The Working Group will therefore take existing APIs into account when working on the RDFa API, and may also document its findings on generic TripleStore APIs in a separate Working Group Note. Such note may become a point of departure for the standardization of a generic TripleStore API in a different Working Group. It is, however, not in the charter of this Working Group to define a general TripleStore API Recommendation.

Because the RDFa API is not based on any previous RDFa work at W3C, use cases for such API usage should be gathered by the Working Group. Beyond influencing the final shape of the API, those use cases could also be documented as part of the “RDFa usage cookbook”.

The group will also take into account the errors on the documents reported by the community since the publication of of the RDFa documents in October 2009, also archived in the rdf-in-xhtml and public-rdfa mailing lists.

Backwards compatibility with RDFa 1.0 is of great importance. That means, in general, that all triples that are produced via the October 2008 version of RDFa, should still be generated in the new version. For each new feature, if there is doubt or a perceived problem with respect to this, the guideline should be to not include the feature in the set of modifications. The only minor feature the Working Group has identified and which may constitute a possible exception to this rule, is the default XML Literal generation. (See the proposal and the corresponding thread for details.)

Success Criteria

Out of Scope

The working group does not assert any authority over the deliverables of the HTML Working Group. The group will have a strong cooperation with the HTML Working Group, ensuring that the RDFa-in-HTML5 work remains compatible with the output of this group.


(The titles of the documents are indicative only)

Although not formally part of the deliverables of this group, it is also the goal to strongly cooperate with the HTML Working Group in publishing an RDFa in HTML5 document, in case the decision of the HTML WG is to finalize that document as a Recommendation.


Note: Dates are based on a charter starting in February 2010. The group will document significant changes from this initial schedule on the group home page.
Specification FPWD LC CR PR Rec
RDFa 1.1 API April 2010 October 2010 January 2011 March 2011 April 2011
RDFa 1.1 Core April 2010 October 2010 January 2011 March 2011 April 2011
RDFa 1.1 in XHTML1.1 April 2010 October 2010 January 2011 March 2011 April 2011
RDFa 1.1 Primer May 2010 March 2011 n/a n/a April 2011
RDF TripleStore APIs (optional) October 2010 April 2011 n/a n/a June 2011
RDFa Usage Cookbook (optional) October 2010 April 2011 n/a n/a June 2011

Timeline View Summary

Dependencies and Liaisons


Internationalization Activity
To ensure that all features introduced to RDFa 1.1 are in line with the requirements of Internationalization on the Web.
Protocols and Formats Working Group
To ensure that all features introduced to RDFa 1.1 are in line with the requirements of Web Accessibility.


W3C Groups

HTML Working Group
To provide input for RDFa in HTML5 and XHTML5 specifications, and to use the feedbacks on those specifications as input to the RDFa 1.1 development.
Web Applications Working Group
To ensure that the API work around RDFa stays in line with the general Web Applications work.
Technical Architecture Group (TAG)
To ensure that RDFa 1.1 is in line with general Web Architecture Principles
Semantic Web Coordination Group
To ensure that the development of RDFa and the APIs are coordinated with other activities around the Semantic Web
SVG Working Group
To ensure that the development of RDFa 1.1 and the APIs are in line with the development of SVG
SVG Interest Group
Provide feedback on the RDFa usage in SVG, as well as test cases that can also be used by SVG 1.2 implementations. The cookbook examples should be coordinated with the SVG group, thereby providing useful examples for the SVG community, too
Protocols and Formats Working Group
To explore whether and how RDFa 1.1 can contribute to the issues raised by future developments of ARIA and the usage of the @role attribute.

External Groups

OASIS Open Document Format for Office Applications (OpenDocument) TC
To synchronize on the RDFa usage in the ODF 1.2


To be successful, the RDFa Working Group is expected to have 5 or more active participants for its duration. Effective participation in the RDFa Working Group is expected to consume one work day per week for each participant; two days per week for editors. The RDFa Working Group will allocate also the necessary resources for building proof-of-concept Validators, Test Suites, and other implementations for each specification.

Participants are reminded of the Good Standing requirements of the W3C Process.


This group primarily conducts its work on the public mailing list public-rdfa@w3.org (with a publicly visible archive) .

Information about the group (deliverables, participants, teleconferences, etc.) is available from the RDFa Working Group home page.

Decision Policy

As explained in the Process Document (section 3.3), this group will seek to make decisions when there is consensus. When the Chair puts a question and observes dissent, after due consideration of different opinions, the Chair should record a decision (possibly after a formal vote) and any objections, and move on.

This charter is written in accordance with Section 3.4, Votes of the W3C Process Document and includes no voting procedures beyond what the Process Document requires.

Patent Policy

This Working Group operates under the W3C Patent Policy (5 February 2004 Version). To promote the widest adoption of Web standards, W3C seeks to issue Recommendations that can be implemented, according to this policy, on a Royalty-Free basis.

For more information about disclosure obligations for this group, please see the W3C Patent Policy Implementation.

About this Charter

This charter for the RDFa Working Group has been created according to section 6.2 of the Process Document. In the event of a conflict between this document or the provisions of any charter and the W3C Process, the W3C Process shall take precedence.

Ivan Herman and Steven Pemberton, W3C staff, with input from Ben Adida, Manu Sporny, Mark Birbeck, and Shane McCarron

$Date: 2010/02/02 16:14:19 $