Large language models (LLMs) achieve strong capabilities by scaling model capacity and training data, yet many real-world deployments rely on smaller models trained or adapted from low-resource data. This gap motivates the need for mechanisms to transfer knowledge from large, high-resource models to smaller, low-resource targets. While model merging provides an effective transfer mechanism, most existing approaches assume architecture-compatible models and therefore cannot directly transfer knowledge from large high-resource LLMs to heterogeneous low-resource targets. In this work, we propose a cross-architecture merging framework based on optimal transport (OT) that aligns activations to infer cross-neuron correspondences between heterogeneous models. The resulting transport plans are then used to guide direct weight-space fusion, enabling effective high-resource to low-resource transfer using only a small set of inputs. Extensive experiments across low-resource languages and specialized domains demonstrate consistent improvements over target models.
Have You Merged My Model? On The Robustness of Large Language Model IP Protection Methods Against Model Merging
Tsinghua University(清华大学);Xidian University(西安电子科技大学);The Hong Kong University of Science and Technology (Guangzhou)(香港科技大学(广州));Zhongguancun Laboratory(中关村实验室);National Financial Cryptography Research Center(国家金融密码研究中心)
MergeRepair: An Exploratory Study on Merging Task-Specific Adapters in Code LLMs for Automated Program Repair
University of British Columbia, Department of Computer Science(不列颠哥伦比亚大学计算机科学系);École de technologie supérieure, Department of Software and IT Engineering(高等技术学院软件与信息技术工程系)
Tübingen AI Center, University of Tübingen(图宾根大学图宾根人工智能中心);University of Cambridge(剑桥大学);Munich Center for ML, Technical University of Munich(慕尼黑工业大学慕尼黑机器学习中心)
Will it Merge? On The Causes of Model Mergeability
Technion - Israel Institute of Technology(技术ion-以色列理工学院);IBM Research AI(IBM人工智能研究部);MIT(麻省理工学院);MIT-IBM Watson AI Lab(麻省理工-IBM沃森人工智能实验室);Hebrew University of Jerusalem(耶路撒冷希伯来大学);Kempner Institute, Harvard University(哈弗大学凯普纳研究所)