AAMAS Conference 2026 Conference Paper
Selective Amnesia: Observation Unlearning in Reinforcement Learning
- Yue Yang
- Jinhao Li
- Hao Wang
Although the concept of machine unlearning has been widely explored in the past few years, unlearning in reinforcement learning (RL) models remains underdeveloped. In this paper, we undertake an in-depth exploration of reinforcement unlearning (RUL), a novel and challenging concept within the field of RL and machine unlearning. We investigate the inherent difficulties associated with RUL, pinpointing two critical factors that contribute to its complexity: agent-environment interactions and the sequential nature of decision-making. To tackle these challenges, we propose an unlearning algorithm that addresses the fundamentals of RUL from the perspective of environment observations, enabling observationlevel unlearning for both tabular and deep Q-learning. By quantitatively assessing the effects of observations through state-action values and modifying and retracing the policy trajectories establishedbytheoriginalmodel, wedemonstratethat, underreasonable assumptions, RUL can effectively eliminate both the immediate and subsequent impacts of the targeted unlearning observation. Empirical evaluations also validate the effectiveness of our RUL approach.