Traitor tracing
Breaking and Repairing Asymmetric Public-Key Traitor Tracing
https://crypto.stanford.edu/DRM2002/asymvpp2.pdf
Efficient Traitor Tracing Algorithms using List Decoding
https://www.iacr.org/archive/asiacrypt2001/22480176.pdf
Practical Attribute-Based Encryption: Traitor Tracing, Revocation, and Large Universe
https://eprint.iacr.org/2014/616.pdf