Open models and their licences

In short: “Open” AI models make their weights available for download. The licence determines whether you may use them freely.

In more detail: “Open weights” means weights are available, training data and code often not. True open source in the sense of the Open Source Initiative is narrower. Licences range from very free (Apache 2.0, MIT) to restricted (community licences with user limits, bans on certain purposes).

In Depth

• Apache 2.0 / MIT: commercial use allowed, keep notices.
• Community licences: often free up to a number of users, then an agreement is needed. Attribution required.
• Research only: no commercial use.
• Outputs: Texts generated by AI may not enjoy copyright protection in Germany (lack of human creation).
• Law: The EU AI Act regulates obligations for AI systems and general-purpose models.

See also: Hugging Face, AI Act