Semantic Web Challenge


Submissions are now invited for the 9th annual Semantic Web Challenge, the premier event for demonstrating practical progress towards achieving the vision of the Semantic Web. The central idea of the Semantic Web is to extend the current human-readable Web by encoding some of the semantics of resources in a machine-processable form. Moving beyond syntax opens the door to more advanced applications and functionality on the Web. Computers will be better able to search, process, integrate and present the content of these resources in a meaningful, intelligent manner.

As the core technological building blocks are now in place, the next challenge is to demonstrate the benefits of semantic technologies by developing integrated, easy to use applications that can provide new levels of Web functionality for end users on the Web or within enterprise settings. Applications submitted should give evidence of clear practical value that goes above and beyond what is possible with conventional web technologies alone.

As in previous years, the Semantic Web Challenge 2011 will consist of two tracks: the Open Track and the Billion Triples Track. The key difference between the two tracks is that the Billion Triples Track requires the participants to make use of the data set that has been crawled from the Web and is provided by the organizers. The Open Track has no such restrictions. As before, the Challenge is open to everyone from industry and academia. The authors of the best applications will be awarded prizes and featured prominently at special sessions during the conference.

The overall goal of this event is to advance our understanding of how Semantic Web technologies can be exploited to produce useful applications for the Web. Semantic Web applications should integrate, combine, and deduce information from various sources to assist users in performing specific tasks.

Challenge Criteria

The Challenge is defined in terms of minimum requirements and additional desirable features that submissions should exhibit. The minimum requirements and the additional desirable features are listed below per track.

Open Track

Minimal requirements

  1. The application has to be an end-user application, i.e. an application that provides a practical value to general Web users or, if this is not the case, at least to domain experts.
  2. The information sources used
    • should be under diverse ownership or control
    • should be heterogeneous (syntactically, structurally, and semantically), and
    • should contain substantial quantities of real world data (i.e. not toy examples).
  3. The meaning of data has to play a central role.
    • Meaning must be represented using Semantic Web technologies.
    • Data must be manipulated/processed in interesting ways to derive useful information and
    • this semantic information processing has to play a central role in achieving things that alternative technologies cannot do as well, or at all;

Additional Desirable Features

In addition to the above minimum requirements, we note other desirable features that will be used as criteria to evaluate submissions.

  • The application provides an attractive and functional Web interface (for human users)
  • The application should be scalable (in terms of the amount of data used and in terms of distributed components working together). Ideally, the application should use all data that is currently published on the Semantic Web.
  • Rigorous evaluations have taken place that demonstrate the benefits of semantic technologies, or validate the results obtained.
  • Novelty, in applying semantic technology to a domain or task that have not been considered before
  • Functionality is different from or goes beyond pure information retrieval
  • The application has clear commercial potential and/or large existing user base
  • Contextual information is used for ratings or rankings
  • Multimedia documents are used in some way
  • There is a use of dynamic data (e.g. workflows), perhaps in combination with static information
  • The results should be as accurate as possible (e.g. use a ranking of results according to context)
  • There is support for multiple languages and accessibility on a range of devices

Billion Triples Track

The specific goal of the Billion Triples Track is to demonstrate the scalability of applications as well as the capability to deal with the specifics of data that has been crawled from the public Web. We stress that the goal of this is not to be a benchmarking effort between triple stores, but rather to demonstrate applications that can work on Web scale using realistic Web-quality data.

Minimal requirements

The primary goal of the Billion Triple track is to demonstrate applications that can work on Web scale using realistic Web-quality data.

  1. The applications must make use of the Billion Triple Challenge 2011 dataset provided by the organisers, which has been crawled from the Web. The functionality of the applications is left open: for example it could involve helping people figure out what is in the dataset via browsing, visualization, profiling, etc., or inferencing that adds information not directly queryable in the original dataset.
  2. The tool or application has to make use of at least the first billion triples from the data provided by the organizers. It is desired that the tool or application uses the complete dataset.
  3. The tool or application is allowed to use other data that can be linked to the Billion Triple Challenge 2011 dataset, but there is still an expectation that the primary focus will be on the data provided.
  4. The tool or application does not have to be specifically an end-user application, as defined for the Open Track Challenge, but usability is a concern. The key goal is to demonstrate an interaction with the large data-set driven by a user or an application.

Additional Desirable Features

In addition to the above minimum requirements, we note other desirable features that will be used as criteria to evaluate submissions.

  • The application should do more than simply store/retrieve large numbers of triples
  • The application or tool(s) should be scalable (in terms of the amount of data used and in terms of distributed components working together)
  • The application or tool(s) should show the use of the very large, mixed quality data set
  • The application should either function in real-time or, if pre-computation is needed, have a real-time realization (but we will take a wide view of "real time" depending on the scale of what is done)

How to participate

Visit in order to participate and register for the Semantic Web Challenge by submitting the required information as well as a link to the application on the online registration form. The form will open in August 2011 and will be open until Firday 30 September, 2011.

The following information must be provided:

  1. Abstract: no more than 200 words.
  2. Description: The description should show details of the system, including why the system is innovative, which features or functions the system provides, what design choices were made and what lessons were learned. The description must include an appendix of 1-2 pages summarising explicitly how participants have addressed the evaluation requirements (including mandatory and any relevant desirable criteria). Papers should not exceed eight pages and must be formatted according to the same guidelines as the papers in the Research Track (see
  3. Web access: The application should be accessible via the web. If the application is not publicly accessible, passwords should be provided. A (short) set of instructions on how to start and use the application should also be provided on the web page.

Descriptions (including the appendix) will be published in the form of online proceedings on the Semantic Web Challenge website.


All participants are required to present their systems at a specific poster session at the ISWC 2011 conference. A jury consisting of experts from industry and academia will judge the systems at the conference. A monetary prize will be provided to the winners of each track, along with publicity for their work. The best applications will also have a chance to appear as full articles in the Journal of Web Semantics.

In the event that one of the tracks receive less than a minimal number of submissions, the organizers reserve the right to merge the two tracks of the competition.

Important Dates



Submissions due

30 September 2011

ISWC 2011

23-27 October 2011