arXiv AI
1d ago

Auditable Unlearning for LLMs

The paper introduces auditability as a fourth evaluation axis for machine unlearning, measuring the separation between forgotten and retained data via a statistic computed by the provider. Experiments on eleven unlearning methods across TOFU, MUSE, and RWKU datasets show none satisfy all four axes, prompting the authors to propose a two‑stage approach: GapWiden, which widens the audit statistic gap using a hinge loss, and GapVeil, an inference‑time rejection sampler that refines responses based on audit statistics. The combined method achieves oracle‑level auditability and leakage control for all tested unlearning techniques, while improving retain performance for most methods.

By Piyush Tiwary, Anushka Srivastava, Prathosh A. P