How can we enrich the commons while building tech that helps rather than harms? FOSS was founded on principles protecting user rights (to use, remix & share software). Through mechanisms like licenses, transparency, and collaboration, open source thrived and transformed our digital world. We’re at a similar crossroad today – AI is staged to change the digital landscape, but limited by questions of ethics and user rights. Taking lessons from open source, we’ll explore the concept of building trustworthy AI by working open and using new data stewardship technologies like data trusts.