ERASE: Precise Machine Unlearning via Geometry-Aware Gradient Shaping and Adaptive Loss Control

Itzik Waizman, Shahar Katz, Lior Wolf


Abstract
Large language models frequently memorize specific factual associations from their training data, necessitating post-hoc removal of targeted knowledge. However, standard gradient-based unlearning techniques treat all parameter directions uniformly, often leading to catastrophic forgetting of general capabilities. We introduce **ERASE** (**E**igenspace-**R**egulated **A**daptive **S**elective **E**rasure), a geometry-aware unlearning framework that combines three complementary mechanisms: (1) a *spectral filter* that attenuates gradient updates along principal directions of retained model knowledge, confining forgetting pressure to low-interference subspaces; (2) *selective error-signal construction*, which restricts gradients to semantically meaningful token positions, avoiding diffuse collateral damage; and (3) an *adaptive Cross-Entropy Target (CET) loss with dynamic per-sample stopping*, which drives each forget example toward a target cross-entropy and halts on convergence, preventing both under- and over-forgetting. Our method requires no reference model, no retain-set loss, and no auxiliary task supervision during training. On TOFU within the OpenUnlearning evaluation framework, ERASE achieves the highest aggregate score across four model families and two forget splits, attaining the best privacy and near-original utility among all compared baselines; on the document-level MUSE-News benchmark, with forget spans recovered automatically via named entity recognition, it simultaneously attains the strongest forgetting and retention with the privacy score closest to the retrain oracle. Our code is publicly available at https://github.com/ItzikWaizman/ERASE.
Anthology ID:
2026.findings-emnlp.2104
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
44796–44824
Language:
URL:
https://aclanthology.org/2026.findings-emnlp.2104/
DOI:
Bibkey:
Cite (ACL):
Itzik Waizman, Shahar Katz, and Lior Wolf. 2026. ERASE: Precise Machine Unlearning via Geometry-Aware Gradient Shaping and Adaptive Loss Control. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 44796–44824, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
ERASE: Precise Machine Unlearning via Geometry-Aware Gradient Shaping and Adaptive Loss Control (Waizman et al., Findings 2026)
Copy Citation:
PDF:
https://aclanthology.org/2026.findings-emnlp.2104.pdf