The ATOM Report: Measuring the Open Language Model Ecosystem
This provides a comprehensive snapshot for researchers, entrepreneurs, and policy advisors tracking the open language model ecosystem.
The paper tackles the problem of measuring the adoption and impact of open language models, documenting that Chinese models overtook U.S. counterparts in summer 2025 and widened the gap, based on analysis of ~1.5K models using metrics like downloads and performance.
We present a comprehensive adoption snapshot of the leading open language models and who is building them, focusing on the ~1.5K mainline open models from the likes of Alibaba's Qwen, DeepSeek, Meta's Llama, that are the foundation of an ecosystem crucial to researchers, entrepreneurs, and policy advisors. We document a clear trend where Chinese models overtook their counterparts built in the U.S. in the summer of 2025 and subsequently widened the gap over their western counterparts. We study a mix of Hugging Face downloads and model derivatives, inference market share, performance metrics and more to make a comprehensive picture of the ecosystem.