SOUL: Unlocking the Power of Second-Order Optimization for LLM Unlearning
On the map: LLM safety and security → Machine unlearning
Abstract (arXiv)
Large Language Models (LLMs) have highlighted the necessity of effective unlearning mechanisms to comply with data regulations and ethical AI practices. LLM unlearning aims at removing undesired data influences and associated model capabilities without compromising utility beyond the scope of unlearning. While interest in studying LLM unlearning is growing, the impact of the optimizer choice for LLM unlearning remains unexplored. In this work, we shed light on the significance of optimizer selection in LLM unlearning for the first time, establishing a clear connection between second-order optimization and influence unlearning (a classical approach using influence functions to update the model for data influence removal). This insight propels us to develop a second-order optimization-based LLM unlearning framework, termed Second-Order UnLearning (SOUL), which extends the static, one-shot model update using influence unlearning to a dynamic, iterative unlearning process. Our extensive experiments show that SOUL consistently outperforms conventional first-order methods across various unlearning tasks, models, and metrics, indicating that second-order optimization offers an effective and broadly applicable solution for LLM unlearning. Codes are available at https://github.com/OPTML-Group/SOUL.
Key facts. Cited by 104 papers in the map (data through 7 Oct 2026). Placed in Machine unlearning, one of 12 directions in LLM safety and security. Builds on 55 of its 79 references that are in the map. First posted on arXiv 28 Apr 2024.
Builds on
55 of 79 references.
Closest ancestors · 19
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Other references · 36
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- 2017Understanding Black-box Predictions via Influence Functionscited by 1,714
- 2020RealToxicityPrompts: Evaluating Neural Toxic Degeneration in Language Modelscited by 1,235
- 2019Machine Unlearningcited by 1,020
- 2023BeaverTails: Towards Improved Safety Alignment of LLM via a Human-Preference Datasetcited by 828
- 2019Eternal Sunshine of the Spotless Net: Selective Forgetting in Deep Networkscited by 599
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- 2023Sophia: A Scalable Stochastic Second-order Optimizer for Language Model Pre-trainingcited by 260
- 2020Approximate Data Deletion from Machine Learning Modelscited by 250
- 2023Composing Parameter-Efficient Modules with Arithmetic Operationscited by 155
- 2019Privacy Risks of Securing Machine Learning Models against Adversarial Examplescited by 136
- 2016On Differentiating Parameterized Argmin and Argmax Problems with Application to Bi-level Optimizationcited by 108
- 2021Federated Unlearning via Class-Discriminative Pruningcited by 108
- 2023Identifying and Mitigating the Security Risks of Generative AIcited by 90
- 2024Machine Unlearning for Image-to-Image Generative Modelscited by 47
- 2020Federated Unlearningcited by 27
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Citing papers per year: 2024: 20; 2025: 50; 2026: 34.
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