The ATOM Report: Measuring the Open Language Model Ecosystem

A comprehensive study of the open language model ecosystem reveals that Chinese AI models, including Qwen and DeepSeek, have overtaken U.S.-developed models like Meta's Llama since summer 2025, with the gap continuing to widen. The research analyzes ~1.5K mainline open models across adoption metrics, market share, and performance to document this significant shift in AI development geography.