From Hugging Face to GitHub: Tracing License Drift in the Open-Source AI
  Ecosystem
Authors: name: James Jewitt, name: Hao Li, name: Bram Adams, name: Gopi Krishnan Rajbahadur, name: Ahmed E. Hassan

Hidden license conflicts in the open-source AI ecosystem pose serious legal
and ethical risks, exposing organizations to potential litigation and users to
undisclosed risk. However, the field lacks a data-driven understanding of how
frequently these conflicts occur, where they originate, and which communities
are most affected. We present the first end-to-end audit of licenses for
datasets and models on Hugging Face, as well as their downstream integration
into open-source software applications, covering 364 thousand datasets, 1.6
million models, and 140 thousand GitHub projects. Our empirical analysis
reveals systemic non-compliance in which 35.5% of model-to-application
transitions eliminate restrictive license clauses by relicensing under
permissive terms. In addition, we prototype an extensible rule engine that
encodes almost 200 SPDX and model-specific clauses for detecting license
conflicts, which can solve 86.4% of license conflicts in software applications.
To support future research, we release our dataset and the prototype engine.
Our study highlights license compliance as a critical governance challenge in
open-source AI and provides both the data and tools necessary to enable
automated, AI-aware compliance at scale.