Part of it is whether the code can be traced back to original AT&T code. Which would be true for e.g. BSD variants (which includes MacOS). https://i.redd.it/kgv

Part of it is whether the code can be traced back to original AT&T code. Which would be true for e.g. BSD variants (which includes MacOS). https://i.redd.it/kgv4ckmz3zb51.jpg https://i.redd.it/kgv4ckmz3zb51.jpg Another part is the trademark and certification fee. https://www.opengroup.org/openbrand/Brandfees.htm https://www.opengroup.org/openbrand/Brandfees.htm