The CLEF-2025 CheckThat! Lab: Subjectivity, Fact-Checking, Claim Normalization, and Retrieval

Firoj Alam; Julia Maria Struß; Tanmoy Chakraborty; Stefan Dietze; Salim Hafid; Katerina Korre; Arianna Muti; Preslav Nakov; V. Venktesh; null More Authors

doi:10.1007/978-3-031-88720-8_68

The CLEF-2025 CheckThat! Lab: Subjectivity, Fact-Checking, Claim Normalization, and Retrieval

Firoj Alam^*, Julia Maria Struß, Tanmoy Chakraborty, Stefan Dietze, Salim Hafid, Katerina Korre, Arianna Muti, Preslav Nakov, V. Venktesh, More Authors

^*Corresponding author for this work

Web Information Systems

Research output: Chapter in Book/Conference proceedings/Edited volume › Conference contribution › Scientific › peer-review

Abstract

The CheckThat! lab aims to advance the development of innovative technologies designed to identify and to counteract online disinformation and manipulation efforts across various languages and platforms. The first five editions of the CheckThat! lab focused on the main tasks of the information verification pipeline: check-worthiness, evidence retrieval and pairing, and verification. Since the 2023 edition, the lab has broadened the focus and addressed new problems on auxiliary tasks supporting research and decision-making during the verification process. In the 2025 edition of the lab, we consider tasks at the core of the verification pipeline again as well as auxiliary tasks: Task 1 is on identification of subjectivity (a follow up of the CheckThat! 2024 edition), Task 2 is on claim normalization, Task 3 addresses fact-checking numerical claims, and Task 4 focuses on scientific web discourse processing. These tasks represent challenging classification and retrieval problems at the document and at the span level, including multilingual settings.

Original language	English
Title of host publication	Advances in Information Retrieval - 47th European Conference on Information Retrieval, ECIR 2025, Proceedings
Editors	Claudia Hauff, Craig Macdonald, Dietmar Jannach, Gabriella Kazai, Franco Maria Nardini, Fabio Pinelli, Fabrizio Silvestri, Nicola Tonellotto
Publisher	Springer
Pages	467-478
Number of pages	12
ISBN (Print)	9783031887192
DOIs	https://doi.org/10.1007/978-3-031-88720-8_68
Publication status	Published - 2025
Event	47th European Conference on Information Retrieval, ECIR 2025 - Lucca, Italy Duration: 6 Apr 2025 → 10 Apr 2025

Publication series

Name	Lecture Notes in Computer Science
Volume	15576 LNCS
ISSN (Print)	0302-9743
ISSN (Electronic)	1611-3349

Conference

Conference	47th European Conference on Information Retrieval, ECIR 2025
Country/Territory	Italy
City	Lucca
Period	6/04/25 → 10/04/25

Bibliographical note

Green Open Access added to TU Delft Institutional Repository as part of the Taverne amendment. More information about this copyright law amendment can be found at https://www.openaccess.nl. Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Keywords

authority finding
disinformation
fact-checking
factuality
model robustness
political bias
subjectivity

Access to Document

10.1007/978-3-031-88720-8_68

Cite this

Alam, F., Struß, J. M., Chakraborty, T., Dietze, S., Hafid, S., Korre, K., Muti, A., Nakov, P., Venktesh, V., & More Authors (2025). The CLEF-2025 CheckThat! Lab: Subjectivity, Fact-Checking, Claim Normalization, and Retrieval. In C. Hauff, C. Macdonald, D. Jannach, G. Kazai, F. M. Nardini, F. Pinelli, F. Silvestri, & N. Tonellotto (Eds.), Advances in Information Retrieval - 47th European Conference on Information Retrieval, ECIR 2025, Proceedings (pp. 467-478). (Lecture Notes in Computer Science; Vol. 15576 LNCS). Springer. https://doi.org/10.1007/978-3-031-88720-8_68

Alam, Firoj ; Struß, Julia Maria ; Chakraborty, Tanmoy et al. / The CLEF-2025 CheckThat! Lab : Subjectivity, Fact-Checking, Claim Normalization, and Retrieval. Advances in Information Retrieval - 47th European Conference on Information Retrieval, ECIR 2025, Proceedings. editor / Claudia Hauff ; Craig Macdonald ; Dietmar Jannach ; Gabriella Kazai ; Franco Maria Nardini ; Fabio Pinelli ; Fabrizio Silvestri ; Nicola Tonellotto. Springer, 2025. pp. 467-478 (Lecture Notes in Computer Science).

@inproceedings{7f9629f12f76419cacab0394d59c1620,

title = "The CLEF-2025 CheckThat! Lab: Subjectivity, Fact-Checking, Claim Normalization, and Retrieval",

abstract = "The CheckThat! lab aims to advance the development of innovative technologies designed to identify and to counteract online disinformation and manipulation efforts across various languages and platforms. The first five editions of the CheckThat! lab focused on the main tasks of the information verification pipeline: check-worthiness, evidence retrieval and pairing, and verification. Since the 2023 edition, the lab has broadened the focus and addressed new problems on auxiliary tasks supporting research and decision-making during the verification process. In the 2025 edition of the lab, we consider tasks at the core of the verification pipeline again as well as auxiliary tasks: Task 1 is on identification of subjectivity (a follow up of the CheckThat! 2024 edition), Task 2 is on claim normalization, Task 3 addresses fact-checking numerical claims, and Task 4 focuses on scientific web discourse processing. These tasks represent challenging classification and retrieval problems at the document and at the span level, including multilingual settings.",

keywords = "authority finding, disinformation, fact-checking, factuality, model robustness, political bias, subjectivity",

author = "Firoj Alam and Stru{\ss}, {Julia Maria} and Tanmoy Chakraborty and Stefan Dietze and Salim Hafid and Katerina Korre and Arianna Muti and Preslav Nakov and V. Venktesh and {More Authors}",

note = "Green Open Access added to TU Delft Institutional Repository as part of the Taverne amendment. More information about this copyright law amendment can be found at https://www.openaccess.nl. Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.; 47th European Conference on Information Retrieval, ECIR 2025 ; Conference date: 06-04-2025 Through 10-04-2025",

year = "2025",

doi = "10.1007/978-3-031-88720-8_68",

language = "English",

isbn = "9783031887192",

series = "Lecture Notes in Computer Science",

publisher = "Springer",

pages = "467--478",

editor = "Claudia Hauff and Craig Macdonald and Dietmar Jannach and Gabriella Kazai and Nardini, {Franco Maria} and Fabio Pinelli and Fabrizio Silvestri and Nicola Tonellotto",

booktitle = "Advances in Information Retrieval - 47th European Conference on Information Retrieval, ECIR 2025, Proceedings",

}

Alam, F, Struß, JM, Chakraborty, T, Dietze, S, Hafid, S, Korre, K, Muti, A, Nakov, P, Venktesh, V & More Authors 2025, The CLEF-2025 CheckThat! Lab: Subjectivity, Fact-Checking, Claim Normalization, and Retrieval. in C Hauff, C Macdonald, D Jannach, G Kazai, FM Nardini, F Pinelli, F Silvestri & N Tonellotto (eds), Advances in Information Retrieval - 47th European Conference on Information Retrieval, ECIR 2025, Proceedings. Lecture Notes in Computer Science, vol. 15576 LNCS, Springer, pp. 467-478, 47th European Conference on Information Retrieval, ECIR 2025, Lucca, Italy, 6/04/25. https://doi.org/10.1007/978-3-031-88720-8_68

The CLEF-2025 CheckThat! Lab: Subjectivity, Fact-Checking, Claim Normalization, and Retrieval. / Alam, Firoj; Struß, Julia Maria; Chakraborty, Tanmoy et al.
Advances in Information Retrieval - 47th European Conference on Information Retrieval, ECIR 2025, Proceedings. ed. / Claudia Hauff; Craig Macdonald; Dietmar Jannach; Gabriella Kazai; Franco Maria Nardini; Fabio Pinelli; Fabrizio Silvestri; Nicola Tonellotto. Springer, 2025. p. 467-478 (Lecture Notes in Computer Science; Vol. 15576 LNCS).

Research output: Chapter in Book/Conference proceedings/Edited volume › Conference contribution › Scientific › peer-review

TY - GEN

T1 - The CLEF-2025 CheckThat! Lab

T2 - 47th European Conference on Information Retrieval, ECIR 2025

AU - Alam, Firoj

AU - Struß, Julia Maria

AU - Chakraborty, Tanmoy

AU - Dietze, Stefan

AU - Hafid, Salim

AU - Korre, Katerina

AU - Muti, Arianna

AU - Nakov, Preslav

AU - Venktesh, V.

AU - More Authors, null

N1 - Green Open Access added to TU Delft Institutional Repository as part of the Taverne amendment. More information about this copyright law amendment can be found at https://www.openaccess.nl. Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

PY - 2025

Y1 - 2025

N2 - The CheckThat! lab aims to advance the development of innovative technologies designed to identify and to counteract online disinformation and manipulation efforts across various languages and platforms. The first five editions of the CheckThat! lab focused on the main tasks of the information verification pipeline: check-worthiness, evidence retrieval and pairing, and verification. Since the 2023 edition, the lab has broadened the focus and addressed new problems on auxiliary tasks supporting research and decision-making during the verification process. In the 2025 edition of the lab, we consider tasks at the core of the verification pipeline again as well as auxiliary tasks: Task 1 is on identification of subjectivity (a follow up of the CheckThat! 2024 edition), Task 2 is on claim normalization, Task 3 addresses fact-checking numerical claims, and Task 4 focuses on scientific web discourse processing. These tasks represent challenging classification and retrieval problems at the document and at the span level, including multilingual settings.

AB - The CheckThat! lab aims to advance the development of innovative technologies designed to identify and to counteract online disinformation and manipulation efforts across various languages and platforms. The first five editions of the CheckThat! lab focused on the main tasks of the information verification pipeline: check-worthiness, evidence retrieval and pairing, and verification. Since the 2023 edition, the lab has broadened the focus and addressed new problems on auxiliary tasks supporting research and decision-making during the verification process. In the 2025 edition of the lab, we consider tasks at the core of the verification pipeline again as well as auxiliary tasks: Task 1 is on identification of subjectivity (a follow up of the CheckThat! 2024 edition), Task 2 is on claim normalization, Task 3 addresses fact-checking numerical claims, and Task 4 focuses on scientific web discourse processing. These tasks represent challenging classification and retrieval problems at the document and at the span level, including multilingual settings.

KW - authority finding

KW - disinformation

KW - fact-checking

KW - factuality

KW - model robustness

KW - political bias

KW - subjectivity

UR - http://www.scopus.com/inward/record.url?scp=105006607851&partnerID=8YFLogxK

U2 - 10.1007/978-3-031-88720-8_68

DO - 10.1007/978-3-031-88720-8_68

M3 - Conference contribution

AN - SCOPUS:105006607851

SN - 9783031887192

T3 - Lecture Notes in Computer Science

SP - 467

EP - 478

BT - Advances in Information Retrieval - 47th European Conference on Information Retrieval, ECIR 2025, Proceedings

A2 - Hauff, Claudia

A2 - Macdonald, Craig

A2 - Jannach, Dietmar

A2 - Kazai, Gabriella

A2 - Nardini, Franco Maria

A2 - Pinelli, Fabio

A2 - Silvestri, Fabrizio

A2 - Tonellotto, Nicola

PB - Springer

Y2 - 6 April 2025 through 10 April 2025

ER -

Alam F, Struß JM, Chakraborty T, Dietze S, Hafid S, Korre K et al. The CLEF-2025 CheckThat! Lab: Subjectivity, Fact-Checking, Claim Normalization, and Retrieval. In Hauff C, Macdonald C, Jannach D, Kazai G, Nardini FM, Pinelli F, Silvestri F, Tonellotto N, editors, Advances in Information Retrieval - 47th European Conference on Information Retrieval, ECIR 2025, Proceedings. Springer. 2025. p. 467-478. (Lecture Notes in Computer Science). doi: 10.1007/978-3-031-88720-8_68