Elon Musk has urged top AI labs and Chinese companies to run checks on other labs' systems. He delivered that message while some in tech are calling for a pause in AI development. Musk himself holds big stakes in AI ventures. Tesla stock fell after his remarks. Musk also appeared at the head of Forbes' annual ranking of the wealthiest Americans. He repeated the notion of joining Tesla and SpaceX. Separately, reports say sexually abusive imagery of children remains on X, even though Musk committed to fixing it.