A Survey on Model MoErging: Recycling and Routing Among Specialized Experts for Collaborative Learning
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Abstract (arXiv)
The availability of performant pre-trained models has led to a proliferation of fine-tuned expert models that are specialized to a particular domain or task. Model MoErging methods aim to recycle expert models to create an aggregate system with improved performance or generalization. A key component of MoErging methods is the creation of a router that decides which expert model(s) to use for a particular input or application. The promise, effectiveness, and large design space of MoErging has spurred the development of many new methods over the past few years. This rapid pace of development has made it challenging to compare different MoErging methods, which are rarely compared to one another and are often validated in different experimental setups. To remedy such gaps, we present a comprehensive survey of MoErging methods that includes a novel taxonomy for cataloging key design choices and clarifying suitable applications for each method. Apart from surveying MoErging research, we inventory software tools and applications that make use of MoErging. We additionally discuss related fields of study such as model merging, multitask learning, and mixture-of-experts models. Taken as a whole, our survey provides a unified overview of existing MoErging methods and creates a solid foundation for future work in this burgeoning field.
Key facts. Cited by 52 papers in the map (data through 7 Oct 2026). Builds on 106 of its 123 references that are in the map. First posted on arXiv 13 Aug 2024.
Builds on
106 of 123 references.
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50 most cited of 106 All 106 (JSON)
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Citing papers per year: 2024: 9; 2025: 25; 2026: 18.
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- 2025Cartridges: Lightweight and general-purpose long context representations via self-studycited by 74
- 2024Merging LoRAs like Playing LEGO: Pushing the Modularity of LoRA to Extremes Through Rank-Wise Clusteringcited by 58
- 2024What Matters for Model Merging at Scale?cited by 52
- 2025MergeBench: A Benchmark for Merging Domain-Specialized LLMscited by 30
- 2025When One LLM Drools, Multi-LLM Collaboration Rulescited by 25
- 2025We Should Chart an Atlas of All the World's Modelscited by 25
- 2024How to Merge Your Multimodal Models Over Time?cited by 23
- 2024Efficient and Effective Weight-Ensembling Mixture of Experts for Multi-Task Model Mergingcited by 22
- 2025Heterogeneous Swarms: Jointly Optimizing Model Roles and Weights for Multi-LLM Systemscited by 22
- 2025Recurrent Knowledge Identification and Fusion for Language Model Continual Learningcited by 14
- 2025FlexOlmo: Open Language Models for Flexible Data Usecited by 14
- 2024SurgeryV2: Bridging the Gap Between Model Merging and Multi-Task Learning with Deep Representation Surgerycited by 12
38 more
- 2025Subspace-Boosted Model Mergingcited by 9
- 2025Don't Throw Away Your Pretrained Modelcited by 9
- 2024SMILE: Zero-Shot Sparse Mixture of Low-Rank Experts Construction From Pre-Trained Foundation Modelscited by 8
- 2025AdaRank: Adaptive Rank Pruning for Enhanced Model Mergingcited by 8
- 2025boldsymbolλ-Orthogonality Regularization for Compatible Representation Learningcited by 8
- 2024Collective Model Intelligence Requires Compatible Specializationcited by 7
- 2025Efficient Model Development through Fine-tuning Transfercited by 6
- 2025SpectR: Dynamically Composing LM Experts with Spectral Routingcited by 6
- 2026MoCo: A One-Stop Shop for Model Collaboration Researchcited by 5
- 2024Glider: Global and Local Instruction-Driven Expert Routercited by 4
- 2025MASS: MoErging through Adaptive Subspace Selectioncited by 4
- 2025FedMerge: Federated Personalization via Model Mergingcited by 4
- 2025AIMMerging: Adaptive Iterative Model Merging Using Training Trajectories for Language Model Continual Learningcited by 4
- 2025RouteMark: A Fingerprint for Intellectual Property Attribution in Routing-based Model Mergingcited by 3
- 2025Mitigating Negative Flips via Margin Preserving Trainingcited by 3
- 2025From Memorization to Parameter Interference: How Overtraining Experts Harms Model Mergingcited by 2
- 2025How does the optimizer implicitly bias the model merging loss landscape?cited by 2
- 2026The Appeal and Reality of Recycling LoRAs with Adaptive Mergingcited by 2
- 2026Modularity is the Bedrock of Natural and Artificial Intelligencecited by 2
- 2026Scaling Participation in Modular AI Systemscited by 2
- 2025Weight Weaving: Parameter Pooling for Data-Free Model Mergingcited by 1
- 2026The Single-Multi Evolution Loop for Self-Improving Model Collaboration Systemscited by 1
- 2026Unlocking the Potential of Continual Model Merging: An ODE Perspectivecited by 1
- 2026Language Models Need Sleep: Learning to Self-Modify and Consolidate Memoriescited by 1
- 2026From Parameters to Feature Space: Task Arithmetic for Backdoor Mitigation in Model Mergingcited by 1
- 2026From Parameters to Behaviors: A Survey of Model Fusion for Large Language Modelscited by 1
- 2024Deep Model Merging: The Sister of Neural Network Interpretability -- A Surveycited by 0
- 2025Out-of-Distribution Graph Models Mergingcited by 0
- 2025Position: Pause Recycling LoRAs and Prioritize Mechanisms to Uncover Limits and Effectivenesscited by 0
- 2025Exploring Sparse Adapters for Scalable Merging of Parameter Efficient Expertscited by 0
- 2025Merging without Forgetting: Continual Fusion of Task-Specific Models via Optimal Transportcited by 0
- 2026GimmBO: Interactive Generative Image Model Merging via Bayesian Optimizationcited by 0
- 2026Fine-Grained Model Merging via Modular Expert Recombinationcited by 0
- 2026The Mean is the Mirage: Entropy-Adaptive Model Merging under Heterogeneous Domain Shifts in Medical Imagingcited by 0
- 2026Trade-offs in Ensembling, Merging and Routing Among Parameter-Efficient Expertscited by 0
- 2026KALAVAI: Predicting When Independent Specialist Fusion Works -- A Quantitative Model for Post-Hoc Cooperative LLM Trainingcited by 0
- 2026Towards Adaptive Continual Model Merging via Manifold-Aware Expert Evolutioncited by 0
- 2026StereoFactory: A Unified Merging Framework for Robust Stereo Matchingcited by 0
50 most cited of 52 All 52 (JSON)
- 2026Spherical Interpolation for Backward-Compatible Multimodal Representations30 Sep 2026
- 2026From Parameters to Behaviors: A Survey of Model Fusion for Large Language Models17 Sep 2026
- 2026DARTS: Decoder-Aware Representation Tuning via Surgery for Model Merging28 Aug 2026
- 2026StereoFactory: A Unified Merging Framework for Robust Stereo Matching16 Jun 2026
- 2026From Parameters to Feature Space: Task Arithmetic for Backdoor Mitigation in Model Merging10 Jun 2026
- 2026Scaling Participation in Modular AI Systems5 Jun 2026
- 2026Language Models Need Sleep: Learning to Self-Modify and Consolidate Memories2 Jun 2026
- 2026Unlocking the Potential of Continual Model Merging: An ODE Perspective19 May 2026
- 2026Towards Adaptive Continual Model Merging via Manifold-Aware Expert Evolution24 Apr 2026
- 2026KALAVAI: Predicting When Independent Specialist Fusion Works -- A Quantitative Model for Post-Hoc Cooperative LLM Training24 Mar 2026
- 2026Trade-offs in Ensembling, Merging and Routing Among Parameter-Efficient Experts3 Mar 2026
- 2026The Mean is the Mirage: Entropy-Adaptive Model Merging under Heterogeneous Domain Shifts in Medical Imaging24 Feb 2026
38 more
- 2026Modularity is the Bedrock of Natural and Artificial Intelligence21 Feb 2026
- 2026The Appeal and Reality of Recycling LoRAs with Adaptive Merging12 Feb 2026
- 2026Fine-Grained Model Merging via Modular Expert Recombination6 Feb 2026
- 2026The Single-Multi Evolution Loop for Self-Improving Model Collaboration Systems5 Feb 2026
- 2026MoCo: A One-Stop Shop for Model Collaboration Research29 Jan 2026
- 2026GimmBO: Interactive Generative Image Model Merging via Bayesian Optimization26 Jan 2026
- 2025Merging without Forgetting: Continual Fusion of Task-Specific Models via Optimal Transport24 Nov 2025
- 2025Mitigating Negative Flips via Margin Preserving Training11 Nov 2025
- 2025Weight Weaving: Parameter Pooling for Data-Free Model Merging15 Oct 2025
- 2025Don't Throw Away Your Pretrained Model10 Oct 2025
- 2025How does the optimizer implicitly bias the model merging loss landscape?6 Oct 2025
- 2025AIMMerging: Adaptive Iterative Model Merging Using Training Trajectories for Language Model Continual Learning22 Sep 2025
- 2025boldsymbolλ-Orthogonality Regularization for Compatible Representation Learning20 Sep 2025
- 2025RouteMark: A Fingerprint for Intellectual Property Attribution in Routing-based Model Merging3 Aug 2025
- 2025Exploring Sparse Adapters for Scalable Merging of Parameter Efficient Experts9 Jul 2025
- 2025FlexOlmo: Open Language Models for Flexible Data Use9 Jul 2025
- 2025Subspace-Boosted Model Merging19 Jun 2025
- 2025From Memorization to Parameter Interference: How Overtraining Experts Harms Model Merging17 Jun 2025
- 2025Position: Pause Recycling LoRAs and Prioritize Mechanisms to Uncover Limits and Effectiveness16 Jun 2025
- 2025Cartridges: Lightweight and general-purpose long context representations via self-study6 Jun 2025
- 2025Out-of-Distribution Graph Models Merging4 Jun 2025
- 2025MergeBench: A Benchmark for Merging Domain-Specialized LLMs16 May 2025
- 2025FedMerge: Federated Personalization via Model Merging9 Apr 2025
- 2025MASS: MoErging through Adaptive Subspace Selection6 Apr 2025
- 2025SpectR: Dynamically Composing LM Experts with Spectral Routing4 Apr 2025
- 2025AdaRank: Adaptive Rank Pruning for Enhanced Model Merging28 Mar 2025
- 2025Efficient Model Development through Fine-tuning Transfer25 Mar 2025
- 2025We Should Chart an Atlas of All the World's Models13 Mar 2025
- 2025Recurrent Knowledge Identification and Fusion for Language Model Continual Learning22 Feb 2025
- 2025Heterogeneous Swarms: Jointly Optimizing Model Roles and Weights for Multi-LLM Systems6 Feb 2025
- 2025When One LLM Drools, Multi-LLM Collaboration Rules6 Feb 2025
- 2024How to Merge Your Multimodal Models Over Time?9 Dec 2024
- 2024Collective Model Intelligence Requires Compatible Specialization4 Nov 2024
- 2024Efficient and Effective Weight-Ensembling Mixture of Experts for Multi-Task Model Merging29 Oct 2024
- 2024SurgeryV2: Bridging the Gap Between Model Merging and Multi-Task Learning with Deep Representation Surgery18 Oct 2024
- 2024Deep Model Merging: The Sister of Neural Network Interpretability -- A Survey16 Oct 2024
- 2024Glider: Global and Local Instruction-Driven Expert Router9 Oct 2024
- 2024What Matters for Model Merging at Scale?4 Oct 2024
50 newest of 52 All 52 (JSON)
- 2024Efficient and Effective Weight-Ensembling Mixture of Experts for Multi-Task Model Mergingcited by 22
- 2025FlexOlmo: Open Language Models for Flexible Data Usecited by 14
- 2025FedMerge: Federated Personalization via Model Mergingcited by 4
- 2025RouteMark: A Fingerprint for Intellectual Property Attribution in Routing-based Model Mergingcited by 3
- 2026Towards Adaptive Continual Model Merging via Manifold-Aware Expert Evolutioncited by 0
- 2026Towards Adaptive Continual Model Merging via Manifold-Aware Expert Evolution24 Apr 2026
- 2025RouteMark: A Fingerprint for Intellectual Property Attribution in Routing-based Model Merging3 Aug 2025
- 2025FlexOlmo: Open Language Models for Flexible Data Use9 Jul 2025
- 2025FedMerge: Federated Personalization via Model Merging9 Apr 2025
- 2024Efficient and Effective Weight-Ensembling Mixture of Experts for Multi-Task Model Merging29 Oct 2024
- 2025Don't Throw Away Your Pretrained Modelcited by 9
- 2025Don't Throw Away Your Pretrained Model10 Oct 2025
- 2024Merging LoRAs like Playing LEGO: Pushing the Modularity of LoRA to Extremes Through Rank-Wise Clusteringcited by 58
- 2024What Matters for Model Merging at Scale?cited by 52
- 2025MergeBench: A Benchmark for Merging Domain-Specialized LLMscited by 30
- 2025When One LLM Drools, Multi-LLM Collaboration Rulescited by 25
- 2025We Should Chart an Atlas of All the World's Modelscited by 25
- 2024How to Merge Your Multimodal Models Over Time?cited by 23
- 2025Heterogeneous Swarms: Jointly Optimizing Model Roles and Weights for Multi-LLM Systemscited by 22
- 2025Recurrent Knowledge Identification and Fusion for Language Model Continual Learningcited by 14
- 2024SurgeryV2: Bridging the Gap Between Model Merging and Multi-Task Learning with Deep Representation Surgerycited by 12
- 2025Subspace-Boosted Model Mergingcited by 9
- 2024SMILE: Zero-Shot Sparse Mixture of Low-Rank Experts Construction From Pre-Trained Foundation Modelscited by 8
- 2025AdaRank: Adaptive Rank Pruning for Enhanced Model Mergingcited by 8
12 most cited of 42 All 42 (JSON)
- 2026From Parameters to Behaviors: A Survey of Model Fusion for Large Language Models17 Sep 2026
- 2026DARTS: Decoder-Aware Representation Tuning via Surgery for Model Merging28 Aug 2026
- 2026StereoFactory: A Unified Merging Framework for Robust Stereo Matching16 Jun 2026
- 2026From Parameters to Feature Space: Task Arithmetic for Backdoor Mitigation in Model Merging10 Jun 2026
- 2026Scaling Participation in Modular AI Systems5 Jun 2026
- 2026Language Models Need Sleep: Learning to Self-Modify and Consolidate Memories2 Jun 2026
- 2026Unlocking the Potential of Continual Model Merging: An ODE Perspective19 May 2026
- 2026KALAVAI: Predicting When Independent Specialist Fusion Works -- A Quantitative Model for Post-Hoc Cooperative LLM Training24 Mar 2026
- 2026Trade-offs in Ensembling, Merging and Routing Among Parameter-Efficient Experts3 Mar 2026
- 2026The Mean is the Mirage: Entropy-Adaptive Model Merging under Heterogeneous Domain Shifts in Medical Imaging24 Feb 2026
- 2026Modularity is the Bedrock of Natural and Artificial Intelligence21 Feb 2026
- 2026The Appeal and Reality of Recycling LoRAs with Adaptive Merging12 Feb 2026
12 newest of 42 All 42 (JSON)
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