Was Thomas Hobbes a natural law philospher or a positive law philosopher?
Both. He believed that there are natural laws that are operated in the state of nature, but that positive law is the law that counts within civilized society, i.e. given the “social contract.” Between two Leviathans, i.e. between England and France considered as sovereign nations, there is no social contract. So when writing about politics in the diplomatic sense he was a natural-law philosopher.