Ciml, it's neither. I've seen enough evidence that sites(corporate)that are listed in the major stock exchanges have a slight advantage in ranking.
I've seen instances of a corporate site beat a 'gov' site inspite of the amount of links pointing to the gov site.
This is considering that the keyword(use to query) is not in the title, description, and in the body on both sites. It is logical then to surmise that the site that has the most back links will rank higher in this situation. But not in the case of public companies.