Particle.news
Download on the App Store

Study Finds AI Can Unmask Pseudonymous Accounts at Scale

Researchers report cheap automated LLM pipelines can link pseudonymous posts to real identities with surprising accuracy.

Overview

  • An ETH Zurich–led preprint describes an LLM-based system that sifts users’ post histories, retrieves candidate profiles via embeddings, and uses model reasoning to score likely matches.
  • Across evaluated datasets, the approach reported up to 68% correct matches at 90% precision, including links between Hacker News accounts and known LinkedIn profiles.
  • The team re-identified 9 of 125 anonymized respondents in an Anthropic dataset by building text-based profiles and searching public web information.
  • The researchers say the process is inexpensive, estimating roughly $1–$4 in compute per profile and under $2,000 for the full set of experiments.
  • The authors and privacy experts warn of misuse risks for dissidents and ordinary users, noting recent AI-enabled doxxing incidents even as the study avoided testing on high-privacy targets and remains unpeer-reviewed.