Apertus: Swiss open source artificial intelligence
Institutional Communication Service
23 September 2025
Apertus is the first large-scale language model developed in Switzerland, created through the collaboration of the Federal Institutes of Technology, the Swiss National Supercomputing Centre (CSCS), and the Dalle Molle Institute for Artificial Intelligence (IDSIA USI-SUPSI). It is an open-source, multilingual model trained on verified data, providing a European alternative to American giants in the field.
Apertus was trained at the Swiss National Supercomputing Centre in Lugano, utilising the ALPS supercomputer, one of the world's most powerful supercomputers. Funded and supported by the Swiss Confederation, its goal is to provide transparent and reliable artificial intelligence that benefits citizens, businesses, and public institutions. Unlike most chatbots, it does not access the Internet or randomly search for information online; instead, it relies solely on verified and authorised documents, which minimises the risk of presenting unreliable or counterfeit content.
For Andrea-Emilio Rizzoli, Director of the Dalle Molle Institute for Artificial Intelligence (IDSIA USI-SUPSI) and Associate Professor at USI Faculty of Informatics, the name itself reflects the philosophy of the project: "The name Apertus implies that this is the first large language model trained with a completely open and transparent data set, accessible to anyone who wants to know what data has been used." A distinctive feature of Apertus is its alignment with Swiss democratic values: "We aimed for the model to provide answers that align with the principles of Swiss democracy. For this reason, the responses produced are checked to assess which are appropriate and which are not. This allows us to offer positive or negative reinforcement based on the types of output produced."
There is no shortage of practical applications, including healthcare: "For instance, consider the Ente Ospedaliero Cantonale (EOC). We are creating systems that automatically generate patient discharge records. The fact that the servers are located here in Lugano, secured and without data being transmitted abroad, is crucial," notes the Director of IDSIA USI-SUPSI. Sectors such as justice and public administration will also benefit from the more efficient management and cataloguing of large amounts of data. According to Professor Rizzoli, it is vital to remember the intrinsic limitations of this type of technology: "These models do not possess consciousness. They are systems that generate sentences based on statistical analysis of training data. They do not think like humans and do not understand the content they produce. While they may create the illusion of conversation, they lack the genuine communicative intent that exists between people."
Apertus marks a significant step for Europe in the global race for artificial intelligence, with the prospect of other countries developing similar solutions, thereby strengthening the continent's technological independence.
Below is the full feature by RSI Il Quotidiano. (Italian only)