I'm not sure how anyone believed they would open source their proprietary AI, or what that would even mean. Did OpenAI ever even officially define what open so

I'm not sure how anyone believed they would open source their proprietary AI, or what that would even mean. Did OpenAI ever even officially define what open source means in this context? Is the training algorithm open source? Or the data model? Or the interpretation engine that reads the model and spits out content? Or some combination of all three?