As far as I know, no website in the world uses ML to decide that you are under 13. They can't by law, afaik, though ianal. My reading of COPPA is that you need

As far as I know, no website in the world uses ML to decide that you are under 13. They can't by law, afaik, though ianal. My reading of COPPA is that you need to have the user tell you they are under 13, or via a parent. If you think they are a child based on websites visited, or whatever? That's not "Actual Knowledge" that it's a child.