
A collection of academic articles, published methodology, and datasets on the subject of machine unlearning.
A sortable version is available here: https://awesome-machine-unlearning.github.io/
Please read and cite our paper:
Thanh Tam Nguyen, Thanh Trung Huynh, Zhao Ren, Phi Le Nguyen, Alan Wee-Chung Liew, Hongzhi Yin, and Quoc Viet Hung Nguyen. 2025. A Survey of Machine Unlearning. ACM Trans. Intell. Syst. Technol. Just Accepted (July 2025). https://doi.org/10.1145/3749987
π We are actively tracking the latest research and welcome contributions to our repository and survey paper. If your studies are relevant, please feel free to create an issue or a pull request.
π° 2025-07-22: Our work has been published in ACM Transactions on Intelligent Systems and Technology. Thanks a lot for your continuous supports.
π° 2025-02-01: Our work has been cited in the International AI Safety Report 2025 in which machine unlearning is a pioneering paradigm to remove sensitive information or harmful data from trained AI models.
@article{10.1145/3749987,
author = {Nguyen, Thanh Tam and Huynh, Thanh Trung and Ren, Zhao and Nguyen, Phi Le and Liew, Alan Wee-Chung and Yin, Hongzhi and Nguyen, Quoc Viet Hung},
title = {A Survey of Machine Unlearning},
year = {2025},
volume = {16},
number = {5},
pages = {1--46},
journal = {ACM Trans. Intell. Syst. Technol.},
}
@article{nguyen2022survey,
title={A Survey of Machine Unlearning},
author={Nguyen, Thanh Tam and Huynh, Thanh Trung and Ren, Zhao and Nguyen, Phi Le and Liew, Alan Wee-Chung and Yin, Hongzhi and Nguyen, Quoc Viet Hung},
journal={arXiv preprint arXiv:2209.02299},
year={2022}
}
Frameworks provide standardized environments, benchmarks, and reproducible research pipelines for studying and evaluating machine unlearning. These works typically focus on methodology, reproducibility, and infrastructure, rather than proposing new unlearning algorithms.
Model-agnostic machine unlearning methodologies include unlearning processes or frameworks that are applicable for different models. In some cases, they provide theoretical guarantees for only a class of models (e.g. linear models). But we still consider them model-agnostic as their core ideas are applicable to complex models (e.g. deep neural networks) with practical results.
| Paper Title | Year | Author | Venue | Model | Code | Type |
|---|
| Forgetting Similar Samples: Can Machine Unlearning Do it Better? | 2026 | Xu et al. | arXiv | - | - | Evaluation |
| Forgetting to Witness: Efficient Federated Unlearning and Its Visible Evaluation | 2026 | Wang et al. | arXiv | Skyeye | - | Federated Unlearning |
| Machine Unlearning of Personally Identifiable Information in Large Language Models | 2025 | Parii et al. | NLLP | PerMUtok | Code | Knowledge Adaptation |
| The forget-set identification problem | 2025 | D'Angelo et al. | Machine Learning | - | - | Dataset Selection |
| ESC: Erasing Space Concept for Knowledge Deletion | 2025 | Lee et al. | CVPR | ESC | [Code] | Knowledge Deletion |
| Decoupled Distillation to Erase: A General Unlearning Method for Any Class-centric Tasks | 2025 | Zhou et al. | CVPR | DELETE | [Code] | Remain-data Free |
| The Right to be Forgotten in Pruning: Unveil Machine Unlearning on Sparse Models | 2025 | Xiao et al. | NeurIPS-RegML | Un-pruning | - | Weight Pruning |
| LoTUS: Large-Scale Machine Unlearning with a Taste of Uncertainty | 2025 | Spartalis et al. | CVPR | LoTUS | [Code] | Uncertainty-based |
| FG-OrIU: Towards Better Forgetting via Feature-Gradient Orthogonality for Incremental Unlearning | 2025 | Feng et al. | ICCV | FG-OrIU | - | Incremental Unlearning |
| Train Once, Forget Precisely: Anchored Optimization for Efficient Post-Hoc Unlearning | 2025 | Sanga et al. | ICML | FAMR | - | Constrained Optimization |
| Towards Lifecycle Unlearning Commitment Management: Measuring Sample-level Unlearning Completeness | 2025 | Wang et al. | USENIX Security | IAM | [Code] | Evaluation |
| PRUNE: A Patching Based Repair Framework for Certifiable Unlearning of Neural Networks | 2025 | Li et al. | arXiv | PRUNE | - | Certifiable Unlearning |
| Evaluating the Defense Potential of Machine Unlearning against Membership Inference Attacks | 2025 | Tsiolakis et al. | arXiv | - | - | Evaluation |
| Potion: Towards Poison Unlearning | 2024 | Schoepf et al. | DMLR | POTION | [Code] | Poison Unlearning |
| Towards Privacy-Guaranteed Label Unlearning in Vertical Federated Learning: Few-Shot Forgetting without Disclosure | 2024 | Gu et al. | arXiv | - | - | Federated Unlearning |
| Releasing Malevolence from Benevolence: The Menace of Benign Data on Machine Unlearning | 2024 | Ma et al. | arXiv | - | - | Unlearning Usability Attack |
| Communication Efficient and Provable Federated Unlearning | 2024 | Tao et al. | VLDB | FATS | [Code] | Federated Unlearning |
| Sequential Informed Federated Unlearning: Efficient and Provable Client Unlearning in Federated Optimization | 2024 | Fraboni et al. | AISTATS | SIFU | [Code] | Differential Privacy, Federated Unlearning |
| Fast-FedUL: A Training-Free Federated Unlearning with Provable Skew Resilience | 2024 | Huynh et al. | ECML-PKDD | Fast-FedUL | [Code] | Federated Unlearning |
| FRAMU: Attention-based Machine Unlearning using Federated Reinforcement Learning | 2024 | Shaik et al. | TKDE | FRAMU | - | Federated Learning, Reinforcement Learning |
| Layer Attack Unlearning: Fast and Accurate Machine Unlearning via Layer Level Attack and Knowledge Distillation | 2024 | Kim et al. | AAAI | LAU | - | Knowledge Adapation |
| Federated Unlearning: a Perspective of Stability and Fairness | 2024 | Shao et al. | arXiv | Stability, Fairness, Verification | - | Federated Unlearning |
| On the Trade-Off between Actionable Explanations and the Right to be Forgotten | 2024 | Pawelczyk et al. | arXiv | - | - | |
| Post-Training Attribute Unlearning in Recommender Systems | 2024 | Chen et al. | arXiv | - | - | PoT-AU |
| CovarNav: Machine Unlearning via Model Inversion and Covariance Navigation | 2024 | Abbasi et al. | arXiv | CovarNav | - | |
| Partially Blinded Unlearning: Class Unlearning for Deep Networks a Bayesian Perspective | 2024 | Panda et al. | arXiv | PBU | - | |
| Unlearning Backdoor Threats: Enhancing Backdoor Defense in Multimodal Contrastive Learning via Local Token Unlearning | 2024 | Liang et al. | arXiv | UBT | - | |
| βΟ: Gradient-based and Task-Agnostic machine Unlearning | 2024 | Trippa et al. | arXiv | - | - | |
| Towards Independence Criterion in Machine Unlearning of Features and Labels | 2024 | Han et al. | arXiv | - | - | |
| Challenging Forgets: Unveiling the Worst-Case Forget Sets in Machine Unlearning | 2024 | Fan et al. | arXiv | - | [Code] | |
| Corrective Machine Unlearning | 2024 | Goel et al. | ICLR DMLR | - | [Code] | |
| Fair Machine Unlearning: Data Removal while Mitigating Disparities | 2024 | Oesterling et al. | AISTATS | fair machine unlearning | [Code] | |
| Label-Agnostic Forgetting: A Supervision-Free Unlearning in Deep Models | 2024 | Shen et al. | arXiv | Label-Agnostic Forgetting | [Code] | |
| CaMU: Disentangling Causal Effects in Deep Model Unlearning | 2024 | Shen et al. | arXiv | CaMU | [Code] | |
| SalUn: Empowering Machine Unlearning via Gradient-based Weight Saliency in Both Image Classification and Generation | 2024 | Fan et al. | ICLR | SalUn | [Code] | Weight Saliency |
| Fast Machine Unlearning Without Retraining Through Selective Synaptic Dampening | 2024 | Foster et al. | AAAI | SSD | [Code] | Retraining-free |
| Learning to Unlearn: Instance-wise Unlearning for Pre-trained Classifiers | 2024 | Cha et al. | AAAI | instance-wise unlearning | [Code] | |
| Parameter-tuning-free data entry error unlearning with adaptive selective synaptic dampening | 2024 | Schoepf et al. | arXiv | ASSD | [Code] | |
| Zero-Shot Machine Unlearning at Scale via Lipschitz Regularization | 2024 | Foster et al. | arXiv | JIT | [Code] | Zero-shot |
| Is Retain Set All You Need in Machine Unlearning? Restoring Performance of Unlearned Models with Out-Of-Distribution Images | 2024 | Bonato et al. | arXiv | SCAR | [Code] | Knowledge Adaptation |
| FedCIO: Efficient Exact Federated Unlearning with Clustering, Isolation, and One-shot Aggregation | 2023 | Qiu et al. | BigData | FedCIO | - | Federated Unlearning, One-Shot |
| Towards bridging the gaps between the right to explanation and the right to be forgotten | 2023 | Krishna et al. | ICML | - | - | e |
| Fast Model DeBias with Machine Unlearning | 2023 | Chen et al. | NIPS | DeBias | [Code] | |
| DUCK: Distance-based Unlearning via Centroid Kinematics | 2023 | Cotogni et al. | arXiv | DUCK | [Code] | |
| Open Knowledge Base Canonicalization with Multi-task Unlearning | 2023 | Liu et al. | arXiv | MulCanon | - | |
| Unlearning via Sparse Representations | 2023 | Shah et al. | arXiv | DKVB | - | Zero-shot Unlearning |
| SecureCut: Federated Gradient Boosting Decision Trees with Efficient Machine Unlearning | 2023 | Zhang et al. | arXiv | SecureCut | - | Vertical Federated Learning |
| Hidden Poison: Machine Unlearning Enables Camouflaged Poisoning Attacks | 2023 | Di et al. | NeurIPS | - | - | Camouflaged data poisoning attacks |
| Model Sparsity Can Simplify Machine Unlearning | 2023 | Jia et al. | NeurIPS | l1-sparse | [Code] | Weight Pruning |
| Fast Model Debias with Machine Unlearning | 2023 | Chen et al. | arXiv | - | - | |
| Tight Bounds for Machine Unlearning via Differential Privacy | 2023 | Huang et al. | arXiv | - | - | |
| Machine Unlearning Methodology base on Stochastic Teacher Network | 2023 | Zhang et al. | ADMA | Model Reconstruction | - | Knowledge Adaptation |
| Fast Machine Unlearning Without Retraining Through Selective Synaptic Dampening | 2023 | Foster et al. | arXiv | SSD | [Code] | |
| From Adaptive Query Release to Machine Unlearning | 2023 | Ullah et al. | arXiv | - | - | Exact Unlearning |
| Towards Adversarial Evaluations for Inexact Machine Unlearning | 2023 | Goel et al. | arXiv | EU-k, CF-k | [Code] | |
| KGA: A General Machine Unlearning Framework Based on Knowledge Gap Alignment | 2023 | Wang et al. | ACL | KGA | [Code] | Knowledge Adaptation |
| On the Trade-Off between Actionable Explanations and the Right to be Forgotten | 2023 | Pawelczyk et al. | arXiv | - | - | |
| Towards Unbounded Machine Unlearning | 2023 | Kurmanji et al. | arXiv | SCRUB | [Code] | approximate unlearning |
| Netflix and Forget: Efficient and Exact Machine Unlearning from Bi-linear Recommendations | 2023 | Xu et al. | arXiv | Unlearn-ALS | - | Exact Unlearning |
| To Be Forgotten or To Be Fair: Unveiling Fairness Implications of Machine Unlearning Methods | 2023 | Zhang et al. | arXiv | - | [Code] | |
| Certified Data Removal in Sum-Product Networks | 2022 | Becker and Liebig | ICKG | UNLEARNSPN | [Code] | Certified Removal Mechanisms |
| Learning with Recoverable Forgetting | 2022 | Ye et al. | ECCV | LIRF | - | |
| Continual Learning and Private Unlearning | 2022 | Liu et al. | CoLLAs | CLPU | [Code] | |
| Verifiable and Provably Secure Machine Unlearning | 2022 | Eisenhofer et al. | arXiv | - | [Code] | Certified Removal Mechanisms |
| VeriFi: Towards Verifiable Federated Unlearning | 2022 | Gao et al. | arXiv | VERIFI | - | Certified Removal Mechanisms |
| FedRecover: Recovering from Poisoning Attacks in Federated Learning using Historical Information | 2022 | Cao et al. | S&P | FedRecover | - | recovery method |
| Fast Yet Effective Machine Unlearning | 2022 | Tarun et al. | arXiv | UNSIR | - | |
| Membership Inference via Backdooring | 2022 | Hu et al. | IJCAI | MIB | [Code] | Membership Inferencing |
| Forget Unlearning: Towards True Data-Deletion in Machine Learning | 2022 | Chourasia et al. | ICLR | - | - | noisy gradient descent |
| Zero-Shot Machine Unlearning | 2022 | Chundawat et al. | arXiv | - | - | |
| Efficient Attribute Unlearning: Towards Selective Removal of Input Attributes from Feature Representations | 2022 | Guo et al. | arXiv | attribute unlearning | - | |
| Few-Shot Unlearning | 2022 | Yoon et al. | ICLR | - | - | |
| Federated Unlearning: How to Efficiently Erase a Client in FL? | 2022 | Halimi et al. | UpML Workshop | - | - | federated learning |
| Machine Unlearning Method Based On Projection Residual | 2022 | Cao et al. | DSAA | - | - | Projection Residual Method |
| Hard to Forget: Poisoning Attacks on Certified Machine Unlearning | 2022 | Marchant et al. | AAAI | - | [Code] | Certified Removal Mechanisms |
| Athena: Probabilistic Verification of Machine Unlearning | 2022 | Sommer et al. | PoPETs | ATHENA | - | |
| FP2-MIA: A Membership Inference Attack Free of Posterior Probability in Machine Unlearning | 2022 | Lu et al. | ProvSec | FP2-MIA | - | inference attack |
| Deletion Inference, Reconstruction, and Compliance in Machine (Un)Learning | 2022 | Gao et al. | PETS | - | - | |
| Prompt Certified Machine Unlearning with Randomized Gradient Smoothing and Quantization | 2022 | Zhang et al. | NeurIPS | PCMU | - | Certified Removal Mechanisms |
| The Right to be Forgotten in Federated Learning: An Efficient Realization with Rapid Retraining | 2022 | Liu et al. | INFOCOM | - | [Code] | |
| Backdoor Defense with Machine Unlearning | 2022 | Liu et al. | INFOCOM | BAERASER | - | Backdoor defense |
| Markov Chain Monte Carlo-Based Machine Unlearning: Unlearning What Needs to be Forgotten | 2022 | Nguyen et al. | ASIA CCS | MCU | - | MCMC Unlearning |
| Can Bad Teaching Induce Forgetting? Unlearning in Deep Networks using an Incompetent Teacher | 2022 | Chundawat et al. | arXiv | - | - | Knowledge Adaptation |
| Efficient Two-Stage Model Retraining for Machine Unlearning | 2022 | Kim and Woo | CVPR Workshop | - | - | |
| Learn to Forget: Machine Unlearning Via Neuron Masking | 2021 | Ma et al. | IEEE | Forsaken | - | Mask Gradients |
| Adaptive Machine Unlearning | 2021 | Gupta et al. | NeurIPS | - | [Code] | Differential Privacy |
| Descent-to-Delete: Gradient-Based Methods for Machine Unlearning | 2021 | Neel et al. | ALT | - | - | Certified Removal Mechanisms |
| Remember What You Want to Forget: Algorithms for Machine Unlearning | 2021 | Sekhari et al. | NeurIPS | - | - | |
| FedEraser: Enabling Efficient Client-Level Data Removal from Federated Learning Models | 2021 | Liu et al. | IWQoS | FedEraser | [Code] | Federated Unlearning |
| Machine Unlearning via Algorithmic Stability | 2021 | Ullah et al. | COLT | TV | - | Certified Removal Mechanisms |
| EMA: Auditing Data Removal from Trained Models | 2021 | Huang et al. | MICCAI | EMA | [Code] | Certified Removal Mechanisms |
| Knowledge-Adaptation Priors | 2021 | Khan and Swaroop | NeurIPS | K-prior | [Code] | Knowledge Adaptation |
| PrIU: A Provenance-Based Approach for Incrementally Updating Regression Models | 2020 | Wu et al. | NeurIPS | PrIU | - | Knowledge Adaptation |
| Eternal Sunshine of the Spotless Net: Selective Forgetting in Deep Networks | 2020 | Golatkar et al. | CVPR | - | - | Certified Removal Mechanisms |
| Learn to Forget: User-Level Memorization Elimination in Federated Learning | 2020 | Liu et al. | arXiv | Forsaken | - | |
| Certified Data Removal from Machine Learning Models | 2020 | Guo et al. | ICML | - | - | Certified Removal Mechanisms |
| Class Clown: Data Redaction in Machine Unlearning at Enterprise Scale | 2020 | Felps et al. | arXiv | - | - | Decremental Learning |
| A Novel Online Incremental and Decremental Learning Algorithm Based on Variable Support Vector Machine | 2019 | Chen et al. | Cluster Computing | - | - | Decremental Learning |
| Making AI Forget You: Data Deletion in Machine Learning | 2019 | Ginart et al. | NeurIPS | - | - | Decremental Learning |
| Lifelong Anomaly Detection Through Unlearning | 2019 | Du et al. | CCS | - | - | |
| Learning Not to Learn: Training Deep Neural Networks With Biased Data | 2019 | Kim et al. | CVPR | - | - | |
| Efficient Repair of Polluted Machine Learning Systems via Causal Unlearning | 2018 | Cao et al. | ASIACCS | KARMA | [Code] | |
| Understanding Black-box Predictions via Influence Functions | 2017 | Koh et al. | ICML | - | [Code] | Certified Removal Mechanisms |
| Towards Making Systems Forget with Machine Unlearning | 2015 | Cao and Yang | S&P | - | | |
| Towards Making Systems Forget with Machine Unlearning | 2015 | Cao et al. | S&P | - | - | Statistical Query Learning |
| Incremental and decremental training for linear classification | 2014 | Tsai et al. | KDD | - | [Code] | Decremental Learning |
| Multiple Incremental Decremental Learning of Support Vector Machines | 2009 | Karasuyama et al. | NIPS | - | - | Decremental Learning |
| Incremental and Decremental Learning for Linear Support Vector Machines | 2007 | Romero et al. | ICANN | - | - | Decremental Learning |
| Decremental Learning Algorithms for Nonlinear Langrangian and Least Squares Support Vector Machines | 2007 | Duan et al. | OSB | - | - | Decremental Learning |
| Multicategory Incremental Proximal Support Vector Classifiers | 2003 | Tveit et al. | KES | - | - | Decremental Learning |
| Incremental and Decremental Proximal Support Vector Classification using Decay Coefficients | 2003 | Tveit et al. | DaWak | - | - | Decremental Learning |
| Incremental and Decremental Support Vector Machine Learning | 2000 | Cauwenberg et al. | NeurIPS | - | - | Decremental Learning |
The model-intrinsic approaches include unlearning methods designed for a specific type of models. Although they are model-intrinsic, their applications are not necessarily narrow, as many ML models can share the same type.
The approaches fallen into this category use data partition, data augmentation and data influence to speed up the retraining process. Methods of attack by data manipulation (e.g. data poisoning) are also included for reference.
| Dataset | #Items | Disk Size | Downstream Application | Description |
|---|
| Adult | 48K+ | 10MB | Classification | |
| Breast Cancer | 569 | <1MB | Classification | |
| Diabetes | 442 | <1MB | Regression | |
| Dataset | #Items | Disk Size | Downstream Application | Description |
|---|
| OGB | 100M+ | 59MB | Classification | |
| Cora | 2K+ | 4.5MB | Classification | |
| MovieLens | 1B+ | 3GB+ | Recommender Systems | |
| Metrics | Formula/Description | Usage |
|---|
| Accuracy | Accuracy on unlearned model on forget set and retrain set | Evaluating the predictive performance of unlearned model |
| Completeness | The overlapping (e.g. Jaccard distance) of output space between the retrained and the unlearned model | Evaluating the indistinguishability between model outputs |
| Unlearn time | The amount of time of unlearning request | Evaluating the unlearning efficiency |
| Relearn Time | The epochs number required for the unlearned model to reach the accuracy of source model | Evaluating the unlearning efficiency (relearn with some data sample) |
| Layer-wise Distance | The weight difference between original model and retrain model | Evaluate the indistinguishability between model parameters |
| Activation Distance | An average of the L2-distance between the unlearned model and retrained modelβs predicted probabilities on the forget set | Evaluating the indistinguishability between model outputs |
| JS-Divergence | Jensen-Shannon divergence between the predictions of the unlearned and retrained model | Evaluating the indistinguishability between model outputs |
| Membership Inference Attack | Recall (#detected items / #forget items) | Verify the influence of forget data on the unlearned model |
| ZRF score | ZRF=1βnf1βi=0βnfββJS(M(xiβ),Tdβ(xiβ)) | The unlearned model should not intentionally give wrong output \(\mathcal{ZRF} = 0\) or random output \(\mathcal{ZRF} = 1\) on the forget item |
| Anamnesis Index (AIN) | AIN=rtβ(Msβ,Morigβ,Ξ±)rtβ(Muβ,Morigβ,Ξ±)β | Zero-shot machine unlearning |
| Epistemic Uncertainty | if \mboxi(w;D)>0, then \mboxefficacy(w;D)=i(w;D)1β; otherwise \mboxefficacy(w;D)=β | How much information the model exposes |
| Model Inversion Attack | Visualization | Qualitative verifications and evaluations |
How to Make Reproducible Research in Machine Unlearning with ERASURE published at IJCAI'25
ERASURE: A Modular and Extensible Framework for Machine Unlearning published at CIKM'25
Unlearn PII - Benchmark designed to evaluate the effectiveness of PII unlearning methods, addressing limitations like evaluation implicit knowledge unlearning and assesing all tokens equally
Open Unlearning - An easily extensible framework unifying LLM unlearning evaluation benchmarks
Vision Unlearning - A framework for unlearning algorithms, datasets, metrics, and evaluation methodologies commonly used in Machine Unlearning for vision-related tasks, such as image classification and image generation
Unlearning Comparator - A visual analytics system for comparative evaluation of machine unlearning methods [Paper] [Demo]
UDS (Unlearning Depth Score) - A white-box metric that measures unlearning depth via two-stage activation patching on internal hidden states, evaluated on TOFU forget10 [Paper] [Project Page]
Disclaimer
Feel free to contact us if you have any queries or exciting news on machine unlearning. In addition, we welcome all researchers to contribute to this repository and further contribute to the knowledge of machine unlearning fields.
If you have some other related references, please feel free to create a Github issue with the paper information. We will glady update the repos according to your suggestions. (You can also create pull requests, but it might take some time for us to do the merge)

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