Apertus (LLM)
Apertus is a Swiss public large language model, developed by the Swiss National AI Initiative. It was released on September 2, 2025.
Designed initially for business and research use cases around the world, Apertus was trained on over 1800 languages, and comes in 8 billion or 70 billion parameter versions and is available on Hugging Face for download. The model was developed aiming to adhere to European copyright law, and is one of the first examples of a sovereign, public AI in the vein of AI nationalism. It is also the first large model to comply with the European Union's Artificial Intelligence Act. At its launch, the model creators emphasized safety and accessibility as priorities over building a frontier model. The first iteration was significantly behind the capabilities of frontier models and needs adaptation for many use cases with chatbots being a secondary but not a primary use case.
As of late 2025, it was considered the largest and most capable fully open model. The capability of future models will depend in part on how much more funding can be secured.