I for one consider such companies to be quasi-government organizations. Especially to the degree that their products are purchased by the government via something other than a open market bid.
Dell doesn't purchase from Microsoft at an open market bid, either. No big organization purchases at open market bid if they can help it. In contrast, the U.S. government is frequently required to purchase on an open market bid (more or less, I'm not sure what your definition of "open market bid" is).
You can hardly be a large business in any developed nation without having substantial business relationships with various world governments.
See: Microsoft, Cisco, Oracle, Boeing, Caterpillar, Lockheed Martin, Ford, GM, 3M, Berkshire Hathaway, General Electric, etc.
Might as well pretend Medtronic, Pfizer or Johnson & Johnson aren't private, because they do so much business with government healthcare systems.