The atmosphere is regarded as a global commons because it can't be owned or controlled by anyone or any country. Earth is the only planet in our solar system that has vast oceans of liquid water. It is Earth's unique oceans that make our planet uniquely life-bearing. Of all the global commons, the oceans are the most explored. Coastal waters can be claimed for private use, like drilling for oil, but the oceans more than two hundred miles from land belong to all.
Information is an unlimited resource that flows worldwide.
Information can't be owned or conquered, and it's getting harder to control, or hide, or hoard.