Source Retrieval for Scientific Web Claims, Fact-Checking Numerical Claims, and Generating Full Fact-Checking Articles

Tasks

Communication

For communication, please join the Discord Server (https://discord.gg/PEMh4a2YHV) and follow the #checkthat lab-channel.

Please register to participate in the CheckThat! Lab tasks.

17 Apr, 2026: an online session will be conducted on 24th of April, 3pm CEST, giving a short overview on each task and a walk-through of the submission system.
17 Apr, 2026: Submission site URLs for Task 1 and 2 are available. Please check task specific page.
17 Feb, 2026: training data was released.
5 Sept, 2025: website is up.

Specific dates will be announced once they are fixed.

17 November 2025: Lab registration opens
December 2025: Release of sample data
February 2026: Release of the training data
23 April 2026: Lab registration closes
24 April 2026: Beginning of the evaluation cycle (test sets release)
07 May 2026: End of the evaluation cycle (run submission)
28 May 2026: Deadline for the submission of working notes [CEUR-WS]
29 May – 27 June 2026: Review process of participant papers
08 June 2026: Submission of Condensed Lab Overviews [LNCS]
15 June 2026: Notification of Acceptance for Condensed Lab Overviews [LNCS]
22 June 2026: Camera Ready Copy of Condensed Lab Overviews [LNCS] due
30 June 2026: Notification of Acceptance for Participant Papers [CEUR-WS]
06 July 2026: Camera Ready Copy of Participant Papers and Extended Lab Overviews [CEUR-WS] due
10 July 2026: Regular Conference Registration Ends
31 August 2026: Late Conference Registration Ends
21-24 September 2026: CLEF 2026 Conference in Jena, Germany

All deadlines are 23:59 in Anywhere on Earth (AOE) timezone.

General:
- Julia Maria Struß, University of Applied Sciences Potsdam, Germany
- Sebastian Schellhammer, GESIS - Leibniz Institute for the Social Sciences, Cologne, Germany
Task 1:
- Stefan Dietze, GESIS - Leibniz Institute for the Social Sciences, Cologne, Germany
- Konstantin Todorov, LIRMM, CNRS, University of Montpellier, Montpellier, France
- Salim Hafid, médialab Sciences Po, Paris, France
Task 2:
- Vinay Setty, University of Stavanger, Norway
- Venktesh V, Delft University of Technology, Nethderlands
Task 3:
- Preslav Nakov, MBZUAI, UAE
- Tanmoy Chakraborty, IIT Delhi, India

TBA

This edition of the CheckThat! lab is held within CLEF 2026, part of the CLEF initiative.