Dissecting Fine-Tuning Unlearning in Large Language Models
On the map: LLM safety and security → Machine unlearning
Abstract (arXiv)
Fine-tuning-based unlearning methods prevail for preventing targeted harmful, sensitive, or copyrighted information within large language models while preserving overall capabilities. However, the true effectiveness of these methods is unclear. In this work, we delve into the limitations of fine-tuning-based unlearning through activation patching and parameter restoration experiments. Our findings reveal that these methods alter the model's knowledge retrieval process, providing further evidence that they do not genuinely erase the problematic knowledge embedded in the model parameters. Instead, the coefficients generated by the MLP components in the model's final layer are the primary contributors to these seemingly positive unlearning effects, playing a crucial role in controlling the model's behaviors. Furthermore, behavioral tests demonstrate that this unlearning mechanism inevitably impacts the global behavior of the models, affecting unrelated knowledge or capabilities. The code is released at https://github.com/yihuaihong/Dissecting-FT-Unlearning.
Key facts. Cited by 26 papers in the map (data through 14 Oct 2026). Placed in Machine unlearning, one of 12 directions in LLM safety and security. Builds on 21 of its 33 references that are in the map. First posted on arXiv 9 Oct 2024.
Builds on
21 of 33 references.
Closest ancestors · 6
Same direction, newest first
- 2024Intrinsic Test of Unlearning Using Parametric Knowledge Traces17 Jun
- 2024Digital Forgetting in Large Language Models: A Survey of Unlearning Methods2 Apr
- 2024Dissecting Language Models: Machine Unlearning via Selective Pruning2 Mar
- 2023Unlearn What You Want to Forget: Efficient Unlearning for LLMs31 Oct
- 2023Who's Harry Potter? Approximate Unlearning in LLMs3 Oct
- 2022Knowledge Unlearning for Mitigating Privacy Risks in Language Models4 Oct
Other references · 15
- 2023Llama 2: Open Foundation and Fine-Tuned Chat Modelscited by 13,028
- 2021Evaluating Large Language Models Trained on Codecited by 8,320
- 2023Direct Preference Optimization: Your Language Model is Secretly a Reward Modelcited by 8,065
- 2022Locating and Editing Factual Associations in GPTcited by 2,691
- 2020Transformer Feed-Forward Layers Are Key-Value Memoriescited by 1,336
- 2022Mass-Editing Memory in a Transformercited by 1,001
- 2024OLMo: Accelerating the Science of Language Modelscited by 613
- 2023Dissecting Recall of Factual Associations in Auto-Regressive Language Modelscited by 528
- 2024Dolma: an Open Corpus of Three Trillion Tokens for Language Model Pretraining Researchcited by 483
- 2024A Mechanistic Understanding of Alignment Algorithms: A Case Study on DPO and Toxicitycited by 185
- 2023Can Sensitive Information Be Deleted From LLMs? Objectives for Defending Against Extraction Attackscited by 158
- 2023Use of LLMs for Illicit Purposes: Threats, Prevention Measures, and Vulnerabilitiescited by 82
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Citing papers per year: 2024: 1; 2025: 10; 2026: 15.
26 papers.
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- 2025Adaptive Multi-Subspace Representation Steering for Attribute Alignment in Large Language Modelscited by 16
- 2025Mechanistic Unveiling of Transformer Circuits: Self-Influence as a Key to Model Reasoningcited by 11
- 2025SoK: Machine Unlearning for Large Language Modelscited by 11
- 2025LUNE: Efficient LLM Unlearning via LoRA Fine-Tuning with Negative Examplescited by 8
- 2026Contrastive Representation Shaping for LLM Unlearningcited by 7
- 2024Towards Multi-dimensional Explanation Alignment for Medical Classificationcited by 6
- 2026Controlling Repetition in Protein Language Modelscited by 5
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- 2026Alignment midtraining for animalscited by 4
- 2025KnowledgeSmith: Uncovering Knowledge Updating in LLMs with Model Editing and Unlearningcited by 3
- 2026Understanding and Enforcing Weight Disentanglement in Task Arithmeticcited by 3
- 2025ZK-APEX: Zero-Knowledge Approximate Personalized Unlearning with Executable Proofscited by 2
14 more
- 2026KUDA: Knowledge Unlearning by Deviating Representation for Large Language Modelscited by 2
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- 2025The Rise of Parameter Specialization for Knowledge Storage in Large Language Modelscited by 1
- 2025Forgetting-MarI: LLM Unlearning via Marginal Information Regularizationcited by 1
- 2026Faithful-Patchscopes: Understanding and Mitigating Model Bias in Hidden Representations Explanation of Large Language Modelscited by 1
- 2026Behemoth: Benchmarking Unlearning in LLMs Using Fully Synthetic Datacited by 0
- 2026EvoMU: Evolutionary Machine Unlearningcited by 0
- 2026Structural Disentanglement in Bilinear MLPs via Architectural Inductive Biascited by 0
- 2026Fast Unlearning at Scale via Margin Self-Correctioncited by 0
- 2026Understanding Machine Unlearning Through the Lens of Mode Connectivitycited by 0
- 2026CleanVideo: Adaptive Concept Erasure for Text-to-Video Diffusion Modelscited by 0
- 2026The Tokens Remember: When Tokenization Bypasses Knowledge Editing and Unlearningcited by 0
- 2026Learning What to Forget: Distributional Unlearning for LLM Representation Spacescited by 0
- 2026Learning What to Forget: Distributional Unlearning for LLM Representation Spaces30 Sep 2026
- 2026The Tokens Remember: When Tokenization Bypasses Knowledge Editing and Unlearning24 Sep 2026
- 2026CleanVideo: Adaptive Concept Erasure for Text-to-Video Diffusion Models29 Jul 2026
- 2026Understanding Machine Unlearning Through the Lens of Mode Connectivity27 Jul 2026
- 2026Multilingual Unlearning in LLMs: Transfer, Dynamics, and Reversibility2 Jun 2026
- 2026Fast Unlearning at Scale via Margin Self-Correction1 Jun 2026
- 2026Understanding and Enforcing Weight Disentanglement in Task Arithmetic18 Apr 2026
- 2026Alignment midtraining for animals21 Mar 2026
- 2026KUDA: Knowledge Unlearning by Deviating Representation for Large Language Models22 Feb 2026
- 2026Structural Disentanglement in Bilinear MLPs via Architectural Inductive Bias5 Feb 2026
- 2026EvoMU: Evolutionary Machine Unlearning2 Feb 2026
- 2026Controlling Repetition in Protein Language Models31 Jan 2026
14 more
- 2026Faithful-Patchscopes: Understanding and Mitigating Model Bias in Hidden Representations Explanation of Large Language Models30 Jan 2026
- 2026Behemoth: Benchmarking Unlearning in LLMs Using Fully Synthetic Data30 Jan 2026
- 2026Contrastive Representation Shaping for LLM Unlearning29 Jan 2026
- 2025ZK-APEX: Zero-Knowledge Approximate Personalized Unlearning with Executable Proofs9 Dec 2025
- 2025LUNE: Efficient LLM Unlearning via LoRA Fine-Tuning with Negative Examples8 Dec 2025
- 2025Towards Reasoning-Preserving Unlearning in Multimodal Large Language Models26 Nov 2025
- 2025Forgetting-MarI: LLM Unlearning via Marginal Information Regularization14 Nov 2025
- 2025KnowledgeSmith: Uncovering Knowledge Updating in LLMs with Model Editing and Unlearning1 Oct 2025
- 2025Adaptive Multi-Subspace Representation Steering for Attribute Alignment in Large Language Models14 Aug 2025
- 2025SoK: Machine Unlearning for Large Language Models10 Jun 2025
- 2025The Rise of Parameter Specialization for Knowledge Storage in Large Language Models22 May 2025
- 2025Understanding Machine Unlearning Through the Lens of Mode Connectivity8 Apr 2025
- 2025Mechanistic Unveiling of Transformer Circuits: Self-Influence as a Key to Model Reasoning13 Feb 2025
- 2024Towards Multi-dimensional Explanation Alignment for Medical Classification28 Oct 2024
- 2025SoK: Machine Unlearning for Large Language Modelscited by 11
- 2025LUNE: Efficient LLM Unlearning via LoRA Fine-Tuning with Negative Examplescited by 8
- 2026Contrastive Representation Shaping for LLM Unlearningcited by 7
- 2025KnowledgeSmith: Uncovering Knowledge Updating in LLMs with Model Editing and Unlearningcited by 3
- 2025ZK-APEX: Zero-Knowledge Approximate Personalized Unlearning with Executable Proofscited by 2
- 2026KUDA: Knowledge Unlearning by Deviating Representation for Large Language Modelscited by 2
- 2026Multilingual Unlearning in LLMs: Transfer, Dynamics, and Reversibilitycited by 2
- 2025Understanding Machine Unlearning Through the Lens of Mode Connectivitycited by 1
- 2025Forgetting-MarI: LLM Unlearning via Marginal Information Regularizationcited by 1
- 2026EvoMU: Evolutionary Machine Unlearningcited by 0
- 2026Structural Disentanglement in Bilinear MLPs via Architectural Inductive Biascited by 0
- 2026Fast Unlearning at Scale via Margin Self-Correctioncited by 0
12 most cited of 15 All 15 (JSON)
- 2026Learning What to Forget: Distributional Unlearning for LLM Representation Spaces30 Sep 2026
- 2026The Tokens Remember: When Tokenization Bypasses Knowledge Editing and Unlearning24 Sep 2026
- 2026Understanding Machine Unlearning Through the Lens of Mode Connectivity27 Jul 2026
- 2026Multilingual Unlearning in LLMs: Transfer, Dynamics, and Reversibility2 Jun 2026
- 2026Fast Unlearning at Scale via Margin Self-Correction1 Jun 2026
- 2026KUDA: Knowledge Unlearning by Deviating Representation for Large Language Models22 Feb 2026
- 2026Structural Disentanglement in Bilinear MLPs via Architectural Inductive Bias5 Feb 2026
- 2026EvoMU: Evolutionary Machine Unlearning2 Feb 2026
- 2026Contrastive Representation Shaping for LLM Unlearning29 Jan 2026
- 2025ZK-APEX: Zero-Knowledge Approximate Personalized Unlearning with Executable Proofs9 Dec 2025
- 2025LUNE: Efficient LLM Unlearning via LoRA Fine-Tuning with Negative Examples8 Dec 2025
- 2025Forgetting-MarI: LLM Unlearning via Marginal Information Regularization14 Nov 2025
12 newest of 15 All 15 (JSON)
- 2024Towards Multi-dimensional Explanation Alignment for Medical Classificationcited by 6
- 2026Controlling Repetition in Protein Language Modelscited by 5
- 2026Alignment midtraining for animalscited by 4
- 2026Understanding and Enforcing Weight Disentanglement in Task Arithmeticcited by 3
- 2025The Rise of Parameter Specialization for Knowledge Storage in Large Language Modelscited by 1
- 2026Faithful-Patchscopes: Understanding and Mitigating Model Bias in Hidden Representations Explanation of Large Language Modelscited by 1
- 2026Understanding and Enforcing Weight Disentanglement in Task Arithmetic18 Apr 2026
- 2026Alignment midtraining for animals21 Mar 2026
- 2026Controlling Repetition in Protein Language Models31 Jan 2026
- 2026Faithful-Patchscopes: Understanding and Mitigating Model Bias in Hidden Representations Explanation of Large Language Models30 Jan 2026
- 2025The Rise of Parameter Specialization for Knowledge Storage in Large Language Models22 May 2025
- 2024Towards Multi-dimensional Explanation Alignment for Medical Classification28 Oct 2024
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