Multiparty Privacy Conflicts (MPCs)

Internet users share ever-increasingly multimedia content online (i.e. photos and videos). Most of the shared contents are co-owned data depicting more than one user (e.g., group photos). Sharing co-owned multimedia content without getting consent causes Multiparty Privacy Conflicts (MPCs) and it might have severe privacy implications on the users’ life. In this project, we aim at the design and evaluation of novel technological interventions to deter users from sharing multimedia content with other users without their consent.

In the first phase of the project, we study how persuasive technologies can influence users towards more considerate and mindful behavior. We explore the use of different persuasive approaches such as reward, punishment, and empathy to discourage users from sharing online.

We design usable privacy-preserving technologies. We also use different experimental approaches such as user studies and longitudinal intervention studies to understand users’ preferences and the effectiveness of the designed strategies in everyday life where real MPC incidences might occur.

In another attempt, we take a more user-centric approach and ask MPC-experienced users to design with us and reflect their experience and creativity to design novel and effective solutions against MPC. We use the well-known participatory design approach inviting social media users who caused MPC and those who suffered from MPC to attend various participatory design activities. In particular, we are interested to explore how existing practices in the justice systems such as deterrence or restoration can be applied in the MPC context and online social networks.

Project Leaders: Kavous Salehzadeh Niksirat, Mauro Cherubini, and Kévin Huguenin.

UNIL Collaborators: Marc-Olivier Boldi.

External Collaborators: Jose Such (King’s College London).


  • K. Salehzadeh Niksirat, E. Anthoine-Milhomme, S. Randin, K. Huguenin, and M. Cherubini. 2021. “I thought you were okay”: Participatory Design with Young Adults to Fight Multiparty Privacy Conflicts in Online Social Networks. In Designing Interactive Systems Conference 2021 (DIS ’21), Virtual Event, USA. ACM, New York, NY, USA, 21 pages. DOI: 10.1145/3461778.3462040 [presentation video] [teaser video]
  • M. Cherubini, K. Niksirat Salehzadeh, M-O. Boldi, H. Keopraseuth, J. M. Such, K. Huguenin. 2021. When Forcing Collaboration is the Most Sensible Choice: Desirability of Precautionary and Dissuasive Mechanisms to Manage Multiparty Privacy Conflicts. Proceedings of the ACM on Human-Computer Interaction, CSCW edition, 35 pages. DOI: 10.1145/3449127


  • K. Salehzadeh Niksirat. 2021. “I thought you were okay”: Participatory Design with Young Adults to Fight Multiparty Privacy Conflicts in Online Social Networks. Presented in a DESI seminar on May 21st. [Watch here]