An Exploration of Decentralized Moderation on Mastodon
Open accessAbstract
Decentralized Online Social Networks (DOSNs) are rising as a valid alternative to traditional centralized platforms like X (Twitter) and Facebook. Mastodon is to date the most widely recognized decentralized social media service. Thousands of servers have been deployed in the last few years due to the availability of open-source software which allows anyone to easily join the network of interconnected servers. Nonetheless, akin to other social media, Mastodon encompasses instances that host harmful or inappropriate content, which demands moderation. However, the decentralized nature of Mastodon servers poses novel challenges for content moderation. In this work, we explore the dynamics of decentralized moderation on Mastodon through the main tool offered to servers’ administrators, namely blocklisting servers to prevent users of an instance from interacting with the content of these servers. Our goal is to shed light on the main traits that characterize blocklisted instances on Mastodon and investigate the emergence of common blocklisting patterns toward specific groups of instances.
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Prior work on decentralized social media has often focused on user behavior within individual implementations of protocols-particularly mastodon.social-and frequently treats decentralization as a given or as a purely technical property.
“Prior work on decentralized social media has often focused on user behavior within individual implementations of protocols-particularly mastodon.social-andfrequently treats decentralization as a given [15,22], or as a purely technical property.”
From Seeing the Politics of Decentralized Social Media Protocols (2026) · cites this paper as [15]
Decentralizing power over infrastructure entails operating Clients, Servers, and Aggregators, imposing significant time, mental health, and financial costs on independent operators.
“Finally, decentralizing power over infrastructure entails operating Clients, Servers, and Aggregators, imposing significant time, mental health, and financial costs on independent operators as noted in recent work [5,8,15,18,51].”
From Seeing the Politics of Decentralized Social Media Protocols (2026) · cites this paper as [15]
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Polarization in Decentralized Online Social Networks
La Cava, L., Mandaglio, D., & Tagarelli, A. (2024) · ACM Web Science Conference · doi:10.1145/3614419.3644013 · Cited by 11 · see citing works
Self-citationSeeing the Politics of Decentralized Social Media Protocols
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“Prior work on decentralized social media has often focused on user behavior within individual implementations of protocols—particularly mastodon.social —and frequently treats decentralization as a given [15, 22], or as a purely technical property.”
- Authors
- Bono, C. A., La Cava, L., Luceri, L., & Pierri, F.
- Affiliations
- Politecnico di Milano (IT)
- DIMES, University of Calabria, Italy
- University of Southern California (US)
- Venue
- ACM Web Science Conference
- Publisher
- ACM
- Published
- 2024-05-21
- Pages
- 53-58
- OpenAlex
- W4394902793
- Cited by
- 18
- References
- 19
- Citations by year
- 2026: 9 · 2025: 8 · 2024: 1
- FWCI
- 5.20
- Type
- conference paper
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- ACM Web Science Conference (WebSci) (publishedVersion, cc-by)
- Archive of Doctoral Theses and Digital Collections (University of Calabria) (submittedVersion)
- Virtual Community of Pathological Anatomy (University of Castilla La Mancha) (submittedVersion, other-oa)
- Topics
- Physical Sciences › Computer Science › Artificial Intelligence › Hate Speech and Cyberbullying Detection
- Social Sciences › Sociology and Political Science › Misinformation and Its Impacts
- Social Sciences › Communication › Social Media and Politics
- Keywords
- Mastodon, decentralized social networks, content moderation, harmful content
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